Publications by authors named "Lynn Hoang"

22 Publications

  • Page 1 of 1

Molecular subclassification of vulvar squamous cell carcinoma: reproducibility and prognostic significance of a novel surgical technique.

Int J Gynecol Cancer 2022 Aug 1;32(8):977-985. Epub 2022 Aug 1.

Division of Gynecologic Pathology, University of Leipzig, Leipzig, Germany.

Objectives: Vulvar squamous cell carcinoma is subclassified into three prognostically relevant groups: (i) human papillomavirus (HPV) associated, (ii) HPV independent p53 abnormal (mutant pattern), and (iii) HPV independent p53 wild type. Immunohistochemistry for p16 and p53 serve as surrogates for HPV viral integration and mutational status. We assessed the reproducibility of the subclassification based on p16 and p53 immunohistochemistry and evaluated the prognostic significance of vulvar squamous cell carcinoma molecular subgroups in a patient cohort treated by vulvar field resection surgery.

Methods: In this retrospective cohort study, 68 cases treated by vulvar field resection were identified from the Leipzig School of Radical Pelvic Surgery. Immunohistochemistry for p16 and p53 was performed at three different institutions and evaluated independently by seven pathologists and two trainees. Tumors were classified into one of four groups: HPV associated, HPV independent p53 wild type, HPV independent p53 abnormal, and indeterminate. Selected cases were further interrogated by (HPV RNA in situ hybridization, sequencing).

Results: Final subclassification yielded 22 (32.4%) HPV associated, 41 (60.3%) HPV independent p53 abnormal, and 5 (7.3%) HPV independent p53 wild type tumors. Interobserver agreement (overall Fleiss' kappa statistic) for the four category classification was 0.74. No statistically significant differences in clinical outcomes between HPV associated and HPV independent vulvar squamous cell carcinoma were observed.

Conclusion: Interobserver reproducibility of vulvar squamous cell carcinoma subclassification based on p16 and p53 immunohistochemistry may support routine use in clinical practice. Vulvar field resection surgery showed no significant difference in clinical outcomes when stratified based on HPV status.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/ijgc-2021-003251DOI Listing
August 2022

Squamous and Glandular Lesions of the Vulva and Vagina: What's New and What Remains Unanswered?

Surg Pathol Clin 2022 Jun 20;15(2):389-405. Epub 2022 May 20.

Vancouver General Hospital and University of British Columbia, Vancouver, British Columbia, Canada. Electronic address:

A number of changes have been introduced into the 5th Edition of the World Health Organization (WHO) Classification of squamous and glandular neoplasms of the vulva and vagina. This review highlights the major shifts in tumor classification, new entities that have been introduced, recommendations for p16 immunohistochemical testing, biomarker use, molecular findings and practical points for pathologists which will affect clinical care. It also touches upon several issues that still remain answered in these rare but undeniably important women's cancers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.path.2022.02.011DOI Listing
June 2022

Data Set for the Reporting of Carcinomas of the Vagina: Recommendations From the International Collaboration on Cancer Reporting (ICCR).

Int J Gynecol Pathol 2022 May 20. Epub 2022 May 20.

Primary carcinomas of the vagina are uncommon and currently detailed recommendations for the reporting of resection specimens of these neoplasms are not widely available. The International Collaboration on Cancer Reporting (ICCR) is developing standardized, evidence-based reporting data sets for multiple cancer sites. We describe the development of a cancer data set by the ICCR expert panel for the reporting of primary vaginal carcinomas and present the core and noncore data elements with explanatory commentaries. This data set has incorporated the updates in the 2020 World Health Organization Classification of Female Genital Tumours, 5th edition. The data set addresses controversial issues such as tumor grading, margin assessment, and the role of ancillary studies. The adoption of this data set into clinical practice will help ensure standardized data collection across different countries, facilitate future research on vaginal carcinomas, and ultimately lead to improvements in patient care.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PGP.0000000000000883DOI Listing
May 2022

HPV-independent, p53-wild-type vulvar intraepithelial neoplasia: a review of nomenclature and the journey to characterize verruciform and acanthotic precursor lesions of the vulva.

Mod Pathol 2022 Apr 18. Epub 2022 Apr 18.

Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.

Vulvar squamous cell carcinomas and their precursors are currently classified by the World Health Organization based on their association with high-risk human papillomavirus (HPV). HPV independent lesions often harbor driver alterations in TP53, usually seen in the setting of chronic vulvar inflammation. However, a group of pre-invasive vulvar squamous lesions is independent from both HPV and mutant TP53. The lesions described within this category feature marked acanthosis, verruciform growth and altered squamous maturation, and over the last two decades several studies have added to their characterization. They have a documented association with verrucous carcinoma and conventional squamous cell carcinoma of the vulva, suggesting a precursor role. They also harbor recurrent genomic alterations in several oncogenes, mainly PIK3CA and HRAS, indicating a neoplastic nature. In this review, we provide a historical perspective and a comprehensive description of these lesions. We also offer an appraisal of the terminology used over the years, going from Vulvar Acanthosis with Altered Differentiation and Verruciform Lichen Simplex Chronicus to Differentiated Exophytic Vulvar Intraepithelial Lesion and Vulvar Aberrant Maturation, the latter term having been recently proposed by the International Society for the Study of Vulvovaginal Diseases. In line with the recognition of these lesions by the 2020 World Health Organization Classification of Tumours as a neoplastic precursor, we herein propose the term HPV-independent, p53-wild-type verruciform acanthotic Vulvar Intraepithelial Neoplasia (HPVi(p53wt) vaVIN), which better conveys not only the pathology but also the neoplastic nature and the biologic risk inherent to these uncommon and challenging lesions. We outline strict morphologic and immunohistochemical criteria for its diagnosis and distinction from mimickers. Immunohistochemistry for p16 and p53 should be performed routinely in the diagnostic work-up of these lesions, and the morphologic alternative term vaVIN should be reserved for instances in which p16/HPV/p53 status is unknown. We also discuss management considerations and the need to further explore precursors within and beyond the spectrum of verruciform acanthotic vulvar intraepithelial neoplasia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41379-022-01079-7DOI Listing
April 2022

The impact of whole genome and transcriptome analysis (WGTA) on predictive biomarker discovery and diagnostic accuracy of advanced malignancies.

J Pathol Clin Res 2022 07 8;8(4):395-407. Epub 2022 Mar 8.

Department of Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, BC, Canada.

In this study, we evaluate the impact of whole genome and transcriptome analysis (WGTA) on predictive molecular profiling and histologic diagnosis in a cohort of advanced malignancies. WGTA was used to generate reports including molecular alterations and site/tissue of origin prediction. Two reviewers analyzed genomic reports, clinical history, and tumor pathology. We used National Comprehensive Cancer Network (NCCN) consensus guidelines, Food and Drug Administration (FDA) approvals, and provincially reimbursed treatments to define genomic biomarkers associated with approved targeted therapeutic options (TTOs). Tumor tissue/site of origin was reassessed for most cases using genomic analysis, including a machine learning algorithm (Supervised Cancer Origin Prediction Using Expression [SCOPE]) trained on The Cancer Genome Atlas data. WGTA was performed on 652 cases, including a range of primary tumor types/tumor sites and 15 malignant tumors of uncertain histogenesis (MTUH). At the time WGTA was performed, alterations associated with an approved TTO were identified in 39 (6%) cases; 3 of these were not identified through routine pathology workup. In seven (1%) cases, the pathology workup either failed, was not performed, or gave a different result from the WGTA. Approved TTOs identified by WGTA increased to 103 (16%) when applying 2021 guidelines. The histopathologic diagnosis was reviewed in 389 cases and agreed with the diagnostic consensus after WGTA in 94% of non-MTUH cases (n = 374). The remainder included situations where the morphologic diagnosis was changed based on WGTA and clinical data (0.5%), or where the WGTA was non-contributory (5%). The 15 MTUH were all diagnosed as specific tumor types by WGTA. Tumor board reviews including WGTA agreed with almost all initial predictive molecular profile and histopathologic diagnoses. WGTA was a powerful tool to assign site/tissue of origin in MTUH. Current efforts focus on improving therapeutic predictive power and decreasing cost to enhance use of WGTA data as a routine clinical test.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cjp2.265DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9161328PMC
July 2022

International Endocervical Adenocarcinoma Criteria and Classification (IECC): An Independent Cohort With Clinical and Molecular Findings.

Int J Gynecol Pathol 2021 Nov;40(6):533-540

Recently, the International Endocervical Adenocarcinoma Criteria and Classification (IECC) has reorganized the classification of endocervical adenocarcinomas (ECAs), separating them into human papilloma virus (HPV)-associated (HPVA) and HPVA independent (HPVI) categories. In this study, we sought to revalidate the IECC clinical findings in an independent cohort and assess the mutational differences between HPVA and HPVI ECAs using next generation sequencing. Consecutive cases of ECAs were reclassified under the IECC. Clinicopathologic information was collected and tissue was sent for targeted next-generation sequencing in 33 genes. Associations between HPV status, clinicopathologic parameters and mutation status, with survival were evaluated. The series comprised of 85/100 HPVA (63 HPVA-usual type, 4 villoglandular, 3 mucinous intestinal, 15 mucinous not otherwise specified) and 15/100 HPVI (9 gastric, 4 mesonephric, 1 clear cell, 1 not otherwise specified). HPVA ECAs presented at a lower age (P=0.001), smaller tumor sizes (P=0.011), less margin positivity (P=0.027), less Silva pattern C (P=0.002), and lower FIGO stages (P=0.020). HPVA had superior survival compared with HPVI ECA [overall survival (P=0.0026), disease-specific survival (P=0.0092), and progression-free survival (P=0.0041)]. Factors that correlated with worse prognosis irrespective of HPV status were FIGO stage, positive margins and lymphovascular invasion (P<0.05). TP53 mutations were detected in a significantly higher proportion of HPVIs than HPVAs (P<<0.001). The study revalidates the IECC system by reaffirming the clinical and prognostic differences between HPVA and HPVI ECAs in an independent dataset.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PGP.0000000000000764DOI Listing
November 2021

Online Training and Self-assessment in the Histopathologic Classification of Endocervical Adenocarcinoma and Diagnosis of Pattern of Invasion: Evaluation of Participant Performance.

Int J Gynecol Pathol 2021 Mar;40(Suppl 1):S14-S23

Histopathologic classification of endocervical adenocarcinomas (EAC) has recently changed, with the new system based on human papillomavirus (HPV)-related morphologic features being incorporated into the 5th edition of the WHO Blue Book (Classification of Tumours of the Female Genital Tract). There has also been the introduction of a pattern-based classification system to assess invasion in HPV-associated (HPVA) endocervical adenocarcinomas that stratifies tumors into 3 groups with different prognoses. To facilitate the introduction of these changes into routine clinical practice, websites with training sets and test sets of scanned whole slide images were designed to improve diagnostic performance in histotype classification of endocervical adenocarcinoma based on the International Endocervical Adenocarcinoma Criteria and Classification (IECC) and assessment of Silva pattern of invasion in HPVA endocervical adenocarcinomas. We report on the diagnostic results of those who have participated thus far in these educational websites. Our goal was to identify areas where diagnostic performance was suboptimal and future educational efforts could be directed. There was very good ability to distinguish HPVA from HPV-independent adenocarcinomas within the WHO/IECC classification, with some challenges in the diagnosis of HPV-independent subtypes, especially mesonephric carcinoma. Diagnosis of HPVA subtypes was not consistent. For the Silva classification, the main challenge was related to distinction between pattern A and pattern B, with a tendency for participants to overdiagnose pattern B invasion. These observations can serve as the basis for more targeted efforts to improve diagnostic performance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PGP.0000000000000757DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7969175PMC
March 2021

Targeted Molecular Sequencing of Recurrent and Multifocal Non-HPV-associated Squamous Cell Carcinoma of the Vulva.

Int J Gynecol Pathol 2021 Jul;40(4):391-399

Recurrent vulvar squamous cell carcinomas (SCCs) are a poorly understood and aggressive group of treatment-resistant neoplasms. Currently, it remains unclear whether these are in fact recurrences of the same primary tumor, or the development of entirely new tumors. Here, to address this question, we examined the mutational profile of a series of patients with recurrent or multifocal non-human papilloma virus (HPV)-associated vulvar SCC. We performed a targeted 33-gene next-generation sequencing panel on a series of 14 patients with recurrent or multifocal non-HPV-associated vulvar SCC and precursor neoplasms. This amounted to 54 cases (33 SCC, 1 verrucous carcinoma, 13 differentiated vulvar intraepithelial neoplasia, and 7 differentiated exophytic vulvar intraepithelial lesion), with 79 mutations detected altogether. TP53 [51/79 (65%)] was the most frequently mutated gene. Mutations in PIK3CA [16/79 (20%)), HRAS [6/79 (8%)], PTEN [4/79 (5%)], EGFR [1/79 (1%)], and GNAS [1/79 (1%)] were occasionally seen. Most patients with SCC [5/9 (56%)] recurrent, 4/5 (80%) multifocal] demonstrated a clonal relationship, and harbored the same mutations in the same genes in metachronous or synchronous tumors. A subset of the recurrent tumors [2/5 (40%)] recurred with additional mutations. These clonal relationships were shared between SCC and differentiated vulvar intraepithelial neoplasia in each case. By contrast, a small number of recurrent tumors [3/9 (33%)] demonstrated novel mutations, entirely different from the primary tumor. Thus, our findings suggest that recurrent non-HPV-associated vulvar SCC can arise from 2 mechanisms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PGP.0000000000000742DOI Listing
July 2021

Clinicopathologic Characteristics of Mesonephric Adenocarcinomas and Mesonephric-like Adenocarcinomas in the Gynecologic Tract: A Multi-institutional Study.

Am J Surg Pathol 2021 04;45(4):498-506

Department of Pathology and Laboratory Medicine, Vancouver General Hospital and University of British Columbia.

Mesonephric adenocarcinoma (MA) and mesonephric-like adenocarcinoma (MLA) are uncommon neoplasms of the gynecologic tract that have until recently been poorly understood. Although their morphologic, immunohistochemical, and molecular profiles have been recently defined, little is known about their clinical behavior. Small studies have demonstrated inconsistent findings and no large studies have examined the clinical behavior of these adenocarcinomas. In this multi-institutional study, representing the largest and most stringently defined cohort of cases to date, we examined the clinicopathologic features of 99 MAs and MLAs (30 MAs of the uterine cervix, 44 MLAs of the endometrium, and 25 MLAs of the ovary). Only tumors with characteristic mesonephric morphology and either immunohistochemical or molecular support were included. Our results demonstrate that the majority of mesonephric neoplasms presented at an advanced stage (II to IV) (15/25 [60%] MA of the cervix, 25/43 [58%] MLA of the endometrium, and 7/18 [39%] MLA of the ovary). The majority (46/89 [52%] overall, 12/24 [50%] MA of the cervix, 24/41 [59%] MLA of the endometrium, and 10/24 [42%] MLA of the ovary) developed recurrences, most commonly distant (9/12 [75%] MA of the cervix, 22/24 [92%] MLA of the endometrium, and 5/9 [56%] MLA of the ovary). The 5-year disease-specific survival was 74% (n=26) for MA of cervix, 72% (n=43) for MLA of endometrium, and 71% (n=23) for MLA of ovary. Our results confirm that mesonephric neoplasms are a clinically aggressive group of gynecologic carcinomas that typically present at an advanced stage, with a predilection for pulmonary recurrence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAS.0000000000001612DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954854PMC
April 2021

Whole-proteome analysis of mesonephric-derived cancers describes new potential biomarkers.

Hum Pathol 2021 02 26;108:1-11. Epub 2020 Oct 26.

Department of Pathology and Laboratory Medicine, The University of British Columbia, Vancouver, BC, V6T 2B5, Canada; Genetic Pathology Evaluation Centre, Vancouver General Hospital, Vancouver, BC, V6H 3Z6, Canada; Department of Anatomical Pathology, Vancouver General Hospital, Vancouver, BC, V5Z 1M9, Canada. Electronic address:

Mesonephric carcinomas (MEs) and female adnexal tumors of probable Wolffian origin (FATWO) are derived from embryologic remnants of Wolffian/mesonephric ducts. Mesonephric-like carcinomas (MLCs) show identical morphology to ME of the cervix but occur in the uterus and ovary without convincing mesonephric remnants. ME, MLC, and FATWO are challenging to diagnose due to their morphologic similarities to Müllerian/paramesonephric tumors, contributing to a lack of evidence-based and tumor-specific treatments. We performed whole-proteomic analysis on 9 ME/MLC and 56 endometrial carcinomas (ECs) to identify potential diagnostic biomarkers. Although there were no convincing differences between ME and MLC, 543 proteins showed increased expression in ME/MLC relative to EC. From these proteins, euchromatic histone lysine methyltransferase 2 (EHMT2), glutathione S-transferase Mu 3 (GSTM3), eukaryotic translation elongation factor 1 alpha 2 (EEF1A2), and glycogen synthase kinase 3 beta were identified as putative biomarkers. Immunohistochemistry was performed on these candidates and GATA3 in 14 ME/MLC, 8 FATWO, 155 EC, and normal tissues. Of the candidates, only GATA3 and EHMT2 were highly expressed in mesonephric remnants and mesonephric-derived male tissues. GATA3 had the highest sensitivity and specificity for ME/MLC versus EC (93% and 99%) but was absent in FATWO. EHMT2 was 100% sensitive for ME/MLC & FATWO but was not specific (65%). Similarly, EEF1A2 was reasonably sensitive to ME/MLC (92%) and FATWO (88%) but was the least specific (38%). GSTM3 performed intermediately (sensitivity for ME/MLC and FATWO: 83% and 38%, respectively; specificity 67%). Although GATA3 remained the best diagnostic biomarker for ME/MLC, we have identified EHMT2, EEF1A2, and GSTM3 as proteins of interest in these cancers. FATWO's cell of origin is uncertain and remains an area for future research.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.humpath.2020.10.005DOI Listing
February 2021

Evaluation of human papillomavirus (HPV) prediction using the International Endocervical Adenocarcinoma Criteria and Classification system, compared to p16 immunohistochemistry and HPV RNA in-situ hybridization.

J Pathol Transl Med 2020 Nov 31;54(6):480-488. Epub 2020 Aug 31.

Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.

Background: The International Endocervical Adenocarcinoma Criteria and Classification (IECC) separated endocervical adenocarcinomas into human papillomavirus (HPV) associated (HPVA) and non-HPV-associated (NHPVA) categories by morphology alone. Our primary objective was to assess the accuracy of HPV prediction by the IECC system compared to p16 immunohistochemistry and HPV RNA in-situ hybridization (RISH). Our secondary goal was to directly compare p16 and HPV RISH concordance.

Methods: Cases were classified by IECC and stained for p16 and HPV RISH on tissue microarray, with discordant p16/HPV RISH cases re-stained on whole tissue sections. Remaining discordant cases (p16/HPV, IECC/p16, IECC/HPV discordances) were re-reviewed by the original pathologists (n = 3) and external expert pathologists (n = 2) blinded to the p16 and HPV RISH results. Final IECC diagnosis was assigned upon independent agreement between all reviewers.

Results: One hundred and eleven endocervical adenocarcinomas were classified originally into 94 HPVA and 17 NHPVA cases. p16 and HPV RISH was concordant in 108/111 cases (97%) independent of the IECC. HPV RISH and p16 was concordant with IECC in 103/111 (93%) and 106/111 (95%), respectively. After expert review, concordance improved to 107/111 (96%) for HPV RISH. After review of the eight discordant cases, one remained as HPVA, four were reclassified to NHPVA from HPVA, two were unclassifiable, and one possibly represented a mixed usual and gastric-type adenocarcinoma.

Conclusions: p16 and HPV RISH have excellent concordance in endocervical adenocarcinomas, and IECC can predict HPV status in most cases. Focal apical mitoses and apoptotic debris on original review led to the misclassification of several NHPVA as HPVA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4132/jptm.2020.07.18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7674758PMC
November 2020

Molecular characterization of invasive and in situ squamous neoplasia of the vulva and implications for morphologic diagnosis and outcome.

Mod Pathol 2021 02 13;34(2):508-518. Epub 2020 Aug 13.

Vancouver General Hospital and University of British Columbia, Vancouver, BC, Canada.

Human papillomavirus (HPV)-independent vulvar squamous cell carcinoma (VSCC) is an aggressive clinical entity. Current diagnostic guidelines for premalignant lesions are ambiguous, and their molecular profile and progression events are still unclear. We selected 75 samples, from 40 patients, including 33 VSCC, 8 verrucous carcinomas (VC), 13 differentiated-type vulvar intraepithelial neoplasia (dVIN), 11 suspicious for dVIN (?dVIN), 6 differentiated exophytic vulvar intraepithelial lesions (DE-VIL), 2 vulvar acanthosis with altered differentiation (VAAD), and 2 usual-type vulvar intraepithelial neoplasia (uVIN/HSIL). Invasive and precursor lesions were matched in 29 cases. Clinical information, p16 immunohistochemistry, and mutation analysis were performed on all lesions. All dVIN, ?dVIN, DE-VIL, and VAAD were p16 negative, all uVIN/HSIL were p16 positive. In the HPV-independent group, mutations were identified in 6 genes: TP53 (n = 40), PIK3CA (n = 20), HRAS (n = 12), MET (n = 5), PTEN (n = 4), and BRAF (n = 1). TP53 mutations occurred in 73% (22/30) VSCC, 85% (11/13) dVIN, 70% (7/10) ?dVIN and no VC (0/8), DE-VIL (0/6) nor VAAD (0/2). Basal atypia was the only reliable feature of TP53 mutations. ?dVIN lesions that were non-acanthotic and atypical but obscured by inflammation, all harbored TP53 mutations. In lesions without TP53 mutations, PIK3CA (50% VC, 33% DE-VIL, 100% VAAD, 40% VSCC) and HRAS (63% VC, 33% DE-VIL, 0% VAAD, 20% VSCC) mutations were found. Mutational progression from in situ to invasive was seen (7/26, 27%) and usually involved TP53 (4/26, 15%). Cases with TP53 and PIK3CA co-mutations had the worse clinical outcomes (p < 0.001). We recommend testing for p53 in all HPV-independent lesions suspicious for dVIN, even in the presence of marked inflammation or non-acanthotic skin, particularly when close to a margin. VC, VAAD, and DE-VIL, were almost never mutated for TP53, but instead often harbored PIK3CA and HRAS mutations. In VSCC, combined TP53 and PIK3CA mutations may inform prognosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41379-020-00651-3DOI Listing
February 2021

Arginine Depletion Therapy with ADI-PEG20 Limits Tumor Growth in Argininosuccinate Synthase-Deficient Ovarian Cancer, Including Small-Cell Carcinoma of the Ovary, Hypercalcemic Type.

Clin Cancer Res 2020 08 14;26(16):4402-4413. Epub 2020 May 14.

Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada.

Purpose: Many rare ovarian cancer subtypes, such as small-cell carcinoma of the ovary, hypercalcemic type (SCCOHT), have poor prognosis due to their aggressive nature and resistance to standard platinum- and taxane-based chemotherapy. The development of effective therapeutics has been hindered by the rarity of such tumors. We sought to identify targetable vulnerabilities in rare ovarian cancer subtypes.

Experimental Design: We compared the global proteomic landscape of six cases each of endometrioid ovarian cancer (ENOC), clear cell ovarian cancer (CCOC), and SCCOHT to the most common subtype, high-grade serous ovarian cancer (HGSC), to identify potential therapeutic targets. IHC of tissue microarrays was used as validation of arginosuccinate synthase (ASS1) deficiency. The efficacy of arginine-depriving therapeutic ADI-PEG20 was assessed using cell lines and patient-derived xenograft mouse models representing SCCOHT.

Results: Global proteomic analysis identified low ASS1 expression in ENOC, CCOC, and SCCOHT compared with HGSC. Low ASS1 levels were validated through IHC in large patient cohorts. The lowest levels of ASS1 were observed in SCCOHT, where ASS1 was absent in 12 of 31 cases, and expressed in less than 5% of the tumor cells in 9 of 31 cases. ASS1-deficient ovarian cancer cells were sensitive to ADI-PEG20 treatment regardless of subtype . Furthermore, in two cell line mouse xenograft models and one patient-derived mouse xenograft model of SCCOHT, once-a-week treatment with ADI-PEG20 (30 mg/kg and 15 mg/kg) inhibited tumor growth .

Conclusions: Preclinical and studies identified ADI-PEG20 as a potential therapy for patients with rare ovarian cancers, including SCCOHT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-19-1905DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7442649PMC
August 2020

p53 Immunohistochemical patterns in HPV-related neoplasms of the female lower genital tract can be mistaken for TP53 null or missense mutational patterns.

Mod Pathol 2020 09 1;33(9):1649-1659. Epub 2020 Apr 1.

Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.

We have recently encountered p53 immunohistochemical (IHC) patterns in human papillomavirus (HPV)-associated carcinomas of the gynecologic tract, which were confused with absent (null) or overexpression TP53 mutational staining. We therefore evaluated p53 and p16 IHC in 25 squamous cell carcinomas (SCC) (16 vulva, 4 Bartholin's gland, and 5 cervix), 20 endocervical adenocarcinomas (EDAC), 14 high-grade squamous intraepithelial lesions (HSIL), 2 adenocarcinoma in situ (AIS), all of which exhibited morphologic features of HPV. Only cases showing diffuse/strong block-like p16 staining were included for further study. All EDACs underwent TP53 sequencing and HPV in situ hybridization (ISH) was performed in selected cases. p53 IHC staining fell into two main patterns. The most common was designated as "markedly reduced (null-like)" (absence or significantly attenuated staining in >70% of cells), which could be confused with true null mutational pattern. This was present in 14/25 (56%) SCCs, 7/14 (50%) HSILs, and 18/20 (90%) EDACs. The second notable pattern was "mid-epithelial (basal sparing)" (distinct absence of staining in basal cells juxtaposed with strong staining in parabasal cells), seen in 10/25 (40%) SCC, 7/14 (50%) HSIL, and none of the EDACs. There was scattered weak to moderate p53 staining (conventional wild type) in 1/25 (4%) SCC and 2/20 (10%) EDAC. No cases showed strong/diffuse overexpression. One EDAC had a TP53 missense mutation and exhibited "markedly reduced (null-like)" staining. HPV ISH revealed an inverse relationship with p53, cells positive for HPV mRNA were negative for p53. Knowledge of these patterns can help pathologists avoid misinterpreting p53 status in the setting of HPVA cancers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41379-020-0527-yDOI Listing
September 2020

Invasive Stratified Mucin-producing Carcinoma (ISMC) of the Cervix: A Study on Morphologic Diversity.

Am J Surg Pathol 2020 07;44(7):873-880

Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY.

Invasive stratified mucin-producing carcinoma (ISMC) is a recently described tumor with similar morphology to the stratified mucin-producing intraepithelial lesion. Stratified mucin-producing intraepithelial lesion and ISMC likely arise from human papillomavirus (HPV)-infected reserve cells in the cervical transformation zone that retain their pluripotential ability to differentiate into various architectural and cytologic patterns. This is important, as small studies have suggested that ISMC may be a morphologic pattern associated with more aggressive behavior than usual HPV-associated adenocarcinoma. We sought to study the morphologic spectrum of this entity and its associations with other, more conventional patterns of HPV-associated carcinomas. Full slide sets from 52 cases of ISMC were reviewed by an international panel of gynecologic pathologists and classified according to the new International Endocervical Criteria and Classification system. Tumors were categorized as ISMC if they demonstrated stromal invasion by solid nests of neoplastic cells with at least focal areas of mucin stratified throughout the entire thickness, as opposed to conventional tall columnar cells with luminal gland formation. Tumors comprising pure ISMC, and those mixed with other morphologic patterns, were included in the analysis. Twenty-nine pure ISMCs (56%) and 23 ISMCs mixed with other components (44%) were identified. Other components included 13 cases of usual-type adenocarcinoma, 6 adenosquamous carcinoma, 3 mucinous-type adenocarcinoma, 1 high-grade neuroendocrine carcinoma. ISMC displayed architectural diversity (insular, lumen-forming, solid, papillary, trabecular, micropapillary, single cells) and variable cytologic appearance (eosinophilic cytoplasm, cytoplasmic clearing, histiocytoid features, glassy cell-like features, signet ring-like features, bizarre nuclei, squamoid differentiation). Awareness of the spectrum of morphologies in ISMC is important for accurate and reproducible diagnosis so that future studies to determine the clinical significance of ISMC can be conducted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAS.0000000000001480DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7289664PMC
July 2020

Major p53 immunohistochemical patterns in in situ and invasive squamous cell carcinomas of the vulva and correlation with TP53 mutation status.

Mod Pathol 2020 08 20;33(8):1595-1605. Epub 2020 Mar 20.

Department of Anatomical Pathology, Vancouver General Hospital, Vancouver, BC, Canada.

The recent literature has shown that vulvar squamous cell carcinoma (VSCC) can be stratified into two prognostically relevant groups based on human papillomavirus (HPV) status. The prognostic value of p53 for further sub-stratification, particularly in the HPV-independent group, has not been agreed upon. This disagreement is likely due to tremendous variations in p53 immunohistochemical (IHC) interpretation. To address this problem, we sought to compare p53 IHC patterns with TP53 mutation status. We studied 61 VSCC (48 conventional VSCC, 2 VSCC with sarcomatoid features, and 11 verrucous carcinomas) and 42 in situ lesions (30 differentiated vulvar intraepithelial neoplasia [dVIN], 9 differentiated exophytic vulvar intraepithelial lesions [deVIL], and 3 high-grade squamous intraepithelial lesions or usual vulvar intraepithelial neoplasia [HSIL/uVIN]). IHC for p16 and p53, and sequencing of TP53 exons 4-9 were performed. HPV in situ hybridization (ISH) was performed in selected cases. We identified six major p53 IHC patterns, two wild-type patterns: (1) scattered, (2) mid-epithelial expression (with basal sparing), and four mutant patterns: (3) basal overexpression, (4) parabasal/diffuse overexpression, (5) absent, and (6) cytoplasmic expression. These IHC patterns were consistent with TP53 mutation status in 58/61 (95%) VSCC and 39/42 (93%) in situ lesions. Cases that exhibited strong scattered staining and those with a weak basal overexpression pattern could be easily confused. The mid-epithelial pattern was exclusively observed in p16-positive lesions; the basal and parabasal layers that had absent p53 staining, appeared to correlate with the cells that were positive for HPV-ISH. This study describes a pattern-based p53 IHC interpretation framework, which can be utilized as a surrogate marker for TP53 mutational status in both VSCC and vulvar in situ lesions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41379-020-0524-1DOI Listing
August 2020

Is Ciprofloxacin in Combination With Beta-lactam Antibiotics a Recipe for Thrombocytosis?: A Case Report of Thrombocytosis in a Patient Receiving Ciprofloxacin and Ceftriaxone.

P T 2019 Dec;44(12):749-753

Dr. Onor is currently a Nephrology Medical Science Liaison at Amgen Inc. He wrote the case report during his tenure as a Clinical Associate Professor of Pharmacy at Xavier University of Louisiana College of Pharmacy in New Orleans, Louisiana; Clinical Assistant Professor of Medicine at Louisiana State University Health Sciences Center School of Medicine in New Orleans; and Internal Medicine Clinical Pharmacist at University Medical Center in New Orleans. Dr. Andonie is a PGY1 Pharmacy Resident at University Medical Center. Dr. Hoang is a PGY1 Pharmacy Resident at Our Lady of the Lake in Baton Rouge, Louisiana. Dr. Walvekar is an Assistant Professor of Clinical Medicine at Louisiana State University Health Sciences Center School of Medicine, where Dr. Guillory and Dr. Sanne are Associate Professors of Clinical Medicine.

Thrombocytosis is defined as a platelet count greater than 400,000/mcL. We report the case of a patient who developed thrombocytosis after receiving ciprofloxacin and ceftriaxone therapy. A 73-year-old African-American female presented to the hospital with altered mental status attributed to sepsis and urinary tract infection. Patient was initiated on multiple empiric antibiotic therapy and was subsequently transitioned to ciprofloxacin and ceftriaxone at different times as definitive therapy for treatment of bacteremia and urinary tract infection. The patient developed thrombocytosis during and/or proximally to the administration of ciprofloxacin and ceftriaxone. A myeloproliferative source for the thrombocytosis was ruled out by the hematology/oncology team with a negative Janus kinase 2 V617F mutation assay result. In addition, other nondrug reactive sources of thrombocytosis (infection and anemia) were generally ruled out because the thrombocytosis was proximally linked with ciprofloxacin and ceftriaxone administration. The Naranjo Adverse Drug Reaction Probability Scale assigned a score of 5, indicating ciprofloxacin or ceftriaxone independently or in combination as a probable cause of thrombocytosis. This case report suggests that ciprofloxacin in combination with ceftriaxone (a beta-lactam antibiotic) may be a probable cause of thrombocytosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8082235PMC
December 2019

c-KIT Analysis and Targeted Molecular Sequencing of Mesonephric Carcinomas of the Female Genital Tract.

Am J Surg Pathol 2020 04;44(4):495-502

Department of Anatomical Pathology, Vancouver General Hospital.

Mesonephric carcinoma is a rare malignancy, thought to derive from Wolffian remnants. To date, no targeted molecular therapeutic options have been identified. On the basis of limited case reports, c-KIT immunohistochemical expression has been reported in female adnexal tumors of Wolffian origin, and targeted therapy with Imatinib has been attempted with mixed success. Currently, it is unclear whether c-KIT immunohistochemical expression is seen in mesonephric carcinoma, a tumor that is thought to be related to female adnexal tumors of Wolffian origin, and how this correlates with KIT mutational status. In this study, we assessed the immunohistochemical expression of c-KIT and KIT mutational status, in a series of 13 mesonephric neoplasms (5 cervical [including 2 cervical carcinosarcomas], 3 uterine corpora, 4 ovarian, and 1 vaginal/pelvic). The intensity of staining and proportion of cells showing cytoplasmic/membranous staining for c-KIT were recorded. KIT was sequenced using a next-generation sequencing panel that targeted 120 hotspots and 17 exons in 33 known actionable cancer genes. This panel included KIT exons 9, 11, and 13, and 6 hotspots (T670, D816, D820, N822, Y823, A829). Although c-KIT immunohistochemical expression was observed in the majority of mesonephric carcinomas (10/12 cases; 83%), no KIT mutations were detected. This cautions pathologists against the use of c-KIT immunohistochemistry as a surrogate marker for KIT-activating mutations in this setting. Consistent with previous studies, the majority of mesonephric neoplasms (10/13; 77%) harbored KRAS mutations. Additional mutations were found in CTNNB1 (2/13, 15%), TP53 (2/13, 15%), and PIK3CA (1/13, 8%).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAS.0000000000001403DOI Listing
April 2020

Should you repeat mismatch repair testing in cases of tumour recurrence? An evaluation of repeat mismatch repair testing by the use of immunohistochemistry in recurrent tumours of the gastrointestinal and gynaecological tracts.

Histopathology 2020 Mar 18;76(4):521-530. Epub 2020 Feb 18.

Division of Anatomic Pathology, Vancouver General Hospital, Vancouver, BC, Canada.

Aims: The role of mismatch repair (MMR) testing has evolved from identifying Lynch syndrome patients to predicting response to immune checkpoint inhibitors. This has led to requests from clinicians to retest recurrences of MMR-proficient primary tumours in the hope that the recurrence may show a different MMR status and qualify the patient for treatment. We aimed to determine whether repeat testing is warranted.

Methods And Results: We evaluated recurrent tumours (local recurrences or metastases) from 137 patients with MMR-proficient primary tumours of the gastrointestinal and gynaecological tracts. The local recurrences and metastases all occurred at least 30 days after resection of the primary tumour. We used a combination of a tissue microarray and whole slide staining to perform immunohistochemistry (IHC) for PMS2, MLH1, MSH2, and MSH6, and compared the results with the MMR status of the primary tumour. Three of 137 (2%) initially showed a discordant staining pattern. However, further investigation showed that these discordances were attributable to some of the known pitfalls associated with MMR IHC interpretation - post-radiotherapy loss of MSH6 expression and subclonal loss of MLH1 staining. We did not identify any cases with a genuine discordance in MMR status.

Conclusion: We conclude that repeat MMR IHC testing of recurrences is not warranted, as MMR status does not change relative to that of the primary tumour.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/his.14026DOI Listing
March 2020

Napsin-A and AMACR are Superior to HNF-1β in Distinguishing Between Mesonephric Carcinomas and Clear Cell Carcinomas of the Gynecologic Tract.

Appl Immunohistochem Mol Morphol 2020 09;28(8):593-601

Department of Pathology and Laboratory Medicine, Vancouver General Hospital.

Mesonephric carcinoma is a rare gynecologic neoplasm commonly mistaken for clear cell carcinoma, because of their overlapping morphologic features. Both tumors are negative for estrogen receptor and p16, magnifying this diagnostic dilemma. Recently, hepatocyte nuclear factor-1 beta (HNF-1β), a marker for clear cell carcinoma, has also been shown to be positive in mesonephric carcinomas. Other more recent markers for clear cell carcinoma, however, such as Napsin-A and alpha-methylacyl-CoA racemase (AMACR), have not yet been studied in mesonephric carcinomas. Here we examine HNF-1β, AMACR, and Napsin-A immunohistochemistry in 18 mesonephric and 55 endometrial/cervical clear cell carcinomas. HNF-1β was considered positive if nuclear staining was present in ≥70% of cells and at least moderate intensity; for Napsin-A and AMACR, any cytoplasmic staining was considered positive (≥1%). H-scores were determined by multiplying the intensity score by proportion score. HNF-1β was positive in a substantial portion of mesonephric carcinomas (9/18, 50%; H-score 98) and clear cell carcinomas (34/55, 62%; H-score 163) and did not distinguish between the 2 entities (specificity, 50%; P-value of H-score=0.08). Napsin-A and AMACR expression was significantly higher in clear cell [43/55 (78%) and 41/55 (75%), respectively] than mesonephric carcinomas [4/18 (22%) and 4/18 (22%) respectively], and helpful in this differential (specificity: 78% and 78%; P<0.05 for both). When Napsin-A and AMACR staining were seen in mesonephric carcinomas, staining was focal (≤5%), whereas staining in clear cell carcinomas was patchy/diffuse. In summary, Napsin-A and AMACR are helpful in distinguishing mesonephric carcinomas from clear cell carcinomas of the female genital tract, but HNF-1β is not.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAI.0000000000000801DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6987010PMC
September 2020

Use of Immunohistochemical Markers (HNF-1β, Napsin A, ER, CTH, and ASS1) to Distinguish Endometrial Clear Cell Carcinoma From Its Morphologic Mimics Including Arias-Stella Reaction.

Int J Gynecol Pathol 2020 Jul;39(4):344-353

Department of Pathology and Laboratory Medicine, University of British Columbia (J.X.J., B.T.-C, B.G., D.G.H., L.N.H.) Department of Molecular Oncology, British Columbia Cancer Research Centre (D.R.C.) Genetic Pathology Evaluation Centre (S.L., A.S.C., C.C.) Department of Pathology, Vancouver General Hospital (B.G., L.N.H.), Vancouver, British Columbia, Canada.

The diagnosis of clear cell (CC) carcinoma of the endometrium can be challenging, especially when endometrioid (EC) and serous (SC) endometrial cancers exhibit nonspecific clear cell changes, in carcinomas with mixed histology and in the setting of Arias-Stella reaction (ASR). In this study, classic CC immunohistochemical markers (Napsin A, HNF-1β, and ER) and 2 recent novel markers, cystathionine gamma-lyase (CTH) and arginosuccinate synthase (ASS1), are assessed for their utility in distinguishing CC from its morphologic mimics. Tissue microarrays containing 64 CC, 128 EC, 5 EC with clear cell change, 16 SC, 5 mixed carcinomas, and 11 whole ASR sections were stained, with 12 additional examples of ASR stained subsequently. A cutoff of 70% and moderate intensity were used for HNF-1β, 80% of cells and strong intensity were used for CTH, and any staining was considered positive for the remaining markers. For differentiating CC from pure EC and SC, HNF-1β, Napsin A, and CTH all performed well. HNF-1β had higher specificity (99.3% vs. 95.1%) but lower sensitivity (55.8% vs. 73.1%) compared with Napsin A. CTH did not substantially outperform HNF- 1β or Napsin A (sensitivity 51.9%, specificity 99.3%). ASS1 and ER were not helpful (specificities of 60.1% and 22.6%). For differentiating CC from ASR, HNF-1β, Napsin A, and CTH stained a large proportion of ASR and were not useful. However, ER positivity and ASS1 negativity were helpful for identifying ASR (specificity 88.2% and 95.1%, respectively). EC with clear cell changes exhibited immunohistochemical patterns similar to pure EC (HNF-1β-, ER+, and CTH-). No markers were useful in confirming the CC components in mixed carcinomas.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PGP.0000000000000609DOI Listing
July 2020

A Comparison of GATA3, TTF1, CD10, and Calretinin in Identifying Mesonephric and Mesonephric-like Carcinomas of the Gynecologic Tract.

Am J Surg Pathol 2018 12;42(12):1596-1606

Department of Pathology and Laboratory Medicine, Vancouver General Hospital and University of British Columbia.

Mesonephric carcinomas of the gynecologic tract are neoplasms that are often under-recognized due to their varied morphologic appearances. Recently, GATA3 and TTF1 have been reported to be useful immunohistochemical markers for distinguishing mesonephric carcinomas from its morphologic mimics. Herein, we compared the performance of GATA3 and TTF1 to the traditional markers used for mesonephric carcinomas, CD10 and calretinin. We studied 694 cases: 8 mesonephric carcinomas (7 cervical [includes 3 mesonephric carcinosarcomas], 1 vaginal), 5 mesonephric-like carcinomas (4 uterine corpus, 1 ovarian), 585 endometrial adenocarcinomas, and 96 cervical adenocarcinomas. Mesonephric-like carcinomas were defined as tumors exhibiting the classic morphologic features of mesonephric carcinoma, but occurring outside of the cervix and without convincing mesonephric remnants. GATA3 had the highest sensitivity and specificity (91% and 94%) compared with TTF1 (45% and 99%), CD10 (73% and 83%), and calretinin (36% and 89%). GATA3, however, also stained a substantial number of uterine carcinosarcomas (23/113, 20%). TTF1 was positive in 5/5 (100%) mesonephric-like carcinomas and only 1/8 (13%) mesonephric carcinomas. In 4/6 (67%) TTF1 positive cases, GATA3 exhibited an inverse staining pattern with TTF1. In summary, GATA3 was the best overall marker for mesonephric and mesonephric-like carcinomas, but cannot be used to distinguish mesonephric carcinosarcomas from Müllerian carcinosarcomas. The inverse staining pattern between GATA3 and TTF1, suggests that TTF1 may be useful when GATA3 is negative in small biopsies where mesonephric or mesonephric-like carcinoma is suspected. The greater TTF1 positivity in mesonephric-like carcinomas suggests they may be biologically different from prototypical mesonephric carcinomas.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAS.0000000000001142DOI Listing
December 2018
-->