Publications by authors named "Michelle Poon"

22 Publications

  • Page 1 of 1

Rapid production of clinical-grade SARS-CoV-2 specific T cells.

Adv Cell Gene Ther 2020 Jul 31:e101. Epub 2020 Jul 31.

Department of Haematology/Oncology KK Women's and Children's Hospital SingHealth Singapore.

Objectives: To determine whether the frequencies of SARS-CoV-2-specific T cells are sufficiently high in the blood of convalescent donors and whether it is technically feasible to manufacture clinical-grade products overnight for T-cell therapy and assessment of COVID-19 immunity.

Methods: One unit of whole blood or leukapheresis was collected from each donor following standard blood bank practices. The leukocytes were stimulated using overlapping peptides of SARS-CoV-2, covering the immunodominant sequence domains of the S protein and the complete sequence of the N and M proteins. Thereafter, functionally reactive cells were enriched overnight using an automated device capturing IFNγ-secreting cells.

Results: From 1 × 10 leukocytes, a median of 0.98 × 10 (range 0.56-2.95) IFNγ + T cells were produced from each of the six donors, suggesting a high frequency of SARS-CoV-2 reactive T cells in their blood, even though only one donor had severe COVID-19 requiring mechanical ventilation whereas the other five donors had minor symptoms. A median of 57% of the enriched T cells were IFNγ+ (range 20%-74%), with preferential enrichment of CD56+ T cells and effector memory T cells. TCRVβ-spectratyping confirmed distinctively tall oligoclonal peaks in final products. With just six donors, the probability that a recipient would share at least one HLA allele with one of the donors is >88% among Caucasian, >95% among Chinese, >97% among Malay, and >99% among Indian populations.

Conclusions: High frequencies of rapid antigen-reactive T cells were found in convalescent donors, regardless of severity of COVID-19. The feasibility of clinical-grade production of SARS-CoV-2-specific T cells overnight for therapeutics and diagnostics is revealed.
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http://dx.doi.org/10.1002/acg2.101DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7404427PMC
July 2020

Phase I Trial of Expanded, Activated Autologous NK-cell Infusions with Trastuzumab in Patients with HER2-positive Cancers.

Clin Cancer Res 2020 Sep 10;26(17):4494-4502. Epub 2020 Jun 10.

Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.

Purpose: Natural killer (NK) cells exert antibody-dependent cell cytotoxicity (ADCC). We infused expanded, activated autologous NK cells to potentiate trastuzumab-mediated ADCC in patients with HER2-positive malignancies.

Patients And Methods: In a phase I trial, patients with treatment-refractory HER2-positive solid tumors received trastuzumab, with or without bevacizumab, and autologous NK cells expanded by 10-day coculture with K562-mb15-41BBL cells. Primary objectives included safety and recommended phase II dose determination; secondary objectives included monitoring NK-cell activity and RECIST antitumor efficacy.

Results: In 60 cultures with cells from 31 subjects, median NK-cell expansion from peripheral blood was 340-fold (range, 91-603). NK cells expressed high levels of CD16, the mediator of ADCC, and exerted powerful killing of trastuzumab-targeted cells. In the 22 subjects enrolled in phase I dose escalation, trastuzumab plus NK cells were well tolerated; MTD was not reached. Phase IB ( = 9) included multiple cycles of NK cells (1 × 10/kg) and addition of bevacizumab. Although no objective response was observed, 6 of 19 subjects who received at least 1 × 10/kg NK cells at cycle 1 had stable disease for ≥6 months (median, 8.8 months; range 6.0-12.0). One patient, the only one with the high-affinity F158V CD16 variant, had a partial response. Peripheral blood NK cells progressively downregulated CD16 postinfusion; paired tumor biopsies showed increased NK cells, lymphocytic infiltrates, and apoptosis posttreatment.

Conclusions: NK-cell therapy in combination with trastuzumab was well tolerated, with target engagement and preliminary antitumor activity, supporting continued assessment of this approach in phase II trials.
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http://dx.doi.org/10.1158/1078-0432.CCR-20-0768DOI Listing
September 2020

Plasma Factors for the Differentiation of Hodgkin's Lymphoma and Diffused Large B Cell Lymphoma and for Monitoring Remission.

J Hematol 2019 Jun 30;8(2):47-54. Epub 2019 Jun 30.

Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.

Background: Hodgkin lymphoma (HL) is one of the most frequent cancers occurring at a young age. Although diagnosis of HL is not difficult, a minimally invasive method to diagnose HL, and a radiation-free method to confirm the remission status are highly desired.

Methods: In this study, we employed cutting-edge Luminex technology to evaluate 67 soluble plasma proteins for their suitability for diagnosis and for confirming remission of classical HL (cHL).

Results: Soluble cluster of differentiation (CD)30 and CC motif chemokine ligand (CCL)22 were identified to be capable of differentiating cHL patients from healthy donors and from patients with diffuse large B cell lymphoma (DLBCL), a disease that shares many characteristics with cHL. Soluble tumor necrosis factor receptor (TNFR)2 was found to be lower in the remission than in the initial diagnosis cohort of cHL patients, and also to be lower in plasmas at remission than in plasmas at initial diagnosis from the same patients. In DLBCL plasmas, concentrations of interleukin (IL)-2, soluble IL-2 receptor and IL-31 changed in patients upon entering remission.

Conclusions: Measurement of these factors may: 1) provide a minimally-invasive method to diagnose and differentiate HL and DLBCL, and 2) make it possible to monitor the remission status of these patients without use of radiation-based imaging.
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http://dx.doi.org/10.14740/jh499DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7153682PMC
June 2019

Acquired Antibody-Mediated Pure Red Cell Aplasia Following Treatment With Darbepoetin.

Ann Acad Med Singap 2020 Jan;49(1):46-48

Division of Nephrology, University Medicine Cluster, National University Health System, Singapore.

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January 2020

A multi-institutional analysis of diffuse large B-cell lymphoma (DLBCL) treated with consolidative radiotherapy and the impact of cell-of-origin on outcomes.

Radiol Oncol 2019 10 25;53(4):473-479. Epub 2019 Oct 25.

Department of Radiation Oncology, National University Cancer Institute Singapore, National University Health System, Singapore Singapore.

Background Patients with diffuse large B-cell lymphoma (DLBCL) with bulky disease and/or those who fail to achieve complete response benefit from the addition of radiotherapy (RT). We aim to review the outcome, as well as determine the impact of cell-of-origin, on patients undergoing consolidative RT. Patients and methods Patients with DLBCL treated with radical intent consolidative RT were included. Clinical, pathological and treatment characteristics were extracted from electronic medical records. Survival outcomes and factors that predict for disease-free survival (DFS) were analysed. Results Seventy-four patients were included in this analysis. The median follow up was 3 years (0.7-16 years). Fifty-eight percent of patients had stage I-II disease, and 61% received at least 6 cycles of chemotherapy. Cell-of-origin was discernible in 60% of patients, and approximately half were classified as Germinal centre origin. The 5-year overall survival (OS) of this group was excellent at 92% (median survival not reached). The 5-year DFS was 73% (95% CI 57-83%). Seven percent (n = 5) of patients experienced local recurrence at a median time of 6 months. Failure to achieve complete response post RT and/or initial bulky disease are significant predictors of inferior DFS. There was no association between cell-of-origin and DFS or OS. Conclusions The outcome of patients who received radiotherapy as consolidation is excellent. Patients who fail to achieve complete response after radiotherapy had poorer outcomes. Despite using radiotherapy, presence of bulky disease remains a significant predictor of disease recurrence. We did not find any association of poorer outcomes, with regards to cell-of-origin, in the use of consolidative RT.
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http://dx.doi.org/10.2478/raon-2019-0045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6884940PMC
October 2019

A multicenter retrospective comparison of induction chemoimmunotherapy regimens on outcomes in transplant-eligible patients with previously untreated mantle cell lymphoma.

Hematol Oncol 2019 Aug 24;37(3):253-260. Epub 2019 May 24.

Department of Haematology, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.

Mantle cell lymphoma (MCL) is an uncommon and typically aggressive form of lymphoma. Although often initially chemosensitive, relapse is common. Several induction and conditioning regimens are used in transplant-eligible patients, and the optimal approach remains unknown. We performed an international, retrospective study of transplant-eligible patients to assess impact of induction chemoimmunotherapy and conditioning regimens on clinical outcomes. We identified 228 patients meeting inclusion criteria. Baseline characteristics were similar among the induction groups except for some variation in age. The type of induction chemoimmunotherapy received did not influence overall response rates (ORRs) (0.43), progression-free survival (PFS) (P > .67), or overall survival (OS) (P > .35) on multivariate analysis (PFS and OS). Delivery of autologous stem cell transplant (ASCT) was associated with favorable PFS and OS (0.01) on univariate analysis only; this benefit was not seen on multivariate analysis-PFS (0.36) and OS (0.21). Compared with busulfan and melphalan (BuMel), the use of the carmustine, etoposide, cytarabine, melphalan (BEAM)-conditioning regimen was associated with inferior PFS (HR = 2.0 [95% CI 1.1-3.6], 0.02) but not OS (HR = 1.1 [95% CI 0.5-2.3], 0.81) on univariate analysis only. Within the limits of a retrospective study and modest power for some comparisons, type of induction therapy did not influence ORR, PFS, or OS for transplant-eligible patients with MCL. International efforts are required to perform randomized clinical trials evaluating chemoimmunotherapy induction regimens.
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http://dx.doi.org/10.1002/hon.2618DOI Listing
August 2019

Multiplexed Fluorescent Immunohistochemical Staining, Imaging, and Analysis in Histological Samples of Lymphoma.

J Vis Exp 2019 01 9(143). Epub 2019 Jan 9.

Cancer Science Institute of Singapore, National University of Singapore; Department of Haematology-Oncology, National University Health System;

Immunohistochemical (IHC) methods for the in-situ analysis of protein expression by light microscopy are a powerful tool for both research and diagnostic purposes. However, the visualization and quantification of multiple antigens in a single tissue section using conventional chromogenic IHC is challenging. Multiplexed imaging is especially relevant in lymphoma research and diagnostics, where markers have to be interpreted in the context of a complex tumor microenvironment. Here we describe a protocol for multiplexed fluorescent IHC staining to enable the quantitative assessment of multiple targets in specific cell types of interest in lymphoma.The method covers aspects of antibody validation, antibody optimization, the multiplex optimization with markers of lymphoma subtypes, the staining of tissue microarray (TMA) slides, and the scanning of the slides, followed by data analysis, with specific reference to lymphoma. Using this method, scores for both the mean intensity of a marker of interest and the percentage positivity are generated to facilitate further quantitative analysis. Multiplexing minimizes sample utilization and provides spatial information for each marker of interest.
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http://dx.doi.org/10.3791/58711DOI Listing
January 2019

Nivolumab for Relapsed/Refractory Diffuse Large B-Cell Lymphoma in Patients Ineligible for or Having Failed Autologous Transplantation: A Single-Arm, Phase II Study.

J Clin Oncol 2019 02 8;37(6):481-489. Epub 2019 Jan 8.

12 Austin Hospital and Olivia Newton-John Cancer Research Institute, Melbourne, VIC, Australia.

Purpose: Treatment options are limited for patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL). Tumor cells can exploit the programmed death-1 checkpoint pathway to evade immune surveillance. In the current study, we evaluated the efficacy and safety of programmed death-1 blockade by nivolumab in patients with relapsed/refractory DLBCL.

Methods: In this phase II, open-label study, patients with relapsed/refractory DLBCL who were ineligible for autologous hematopoietic cell transplantation (auto-HCT) or who had experienced failure with auto-HCT received nivolumab 3 mg/kg every 2 weeks. We assessed the efficacy and safety of nivolumab as well as genetic alterations of 9p24.1.

Results: Among 121 treated patients, patients in the auto-HCT-failed cohort (n = 87) received a median of four nivolumab doses and a median of three doses were administered to those in the auto-HCT-ineligible cohort (n = 34). At a median follow-up of 9 months in the auto-HCT-failed cohort and 6 months in the auto-HCT-ineligible cohort, independently assessed objective response rates were 10% and 3%, and median durations of response were 11 and 8 months, respectively. Median progression-free survival and overall survival were 1.9 and 12.2 months in the auto-HCT-failed cohort and 1.4 and 5.8 months in the auto-HCT-ineligible cohort respectively. All three patients with complete remission-3% of the auto-HCT-failed cohort-had durable response (11 or more, 14 or more, and 17 months). Treatment-related grade 3 and 4 adverse events were reported in 24% of patients. The most common were neutropenia (4%), thrombocytopenia (3%), and increased lipase (3%). Of all evaluable samples for 9p24.1 analysis, 16% exhibited low-level copy gain and 3% had amplification.

Conclusion: Nivolumab monotherapy is associated with a favorable safety profile but a low overall response rate among patients with DLBCL who are ineligible for auto-HCT or who experienced failure with auto-HCT. Genetic alterations of 9p24.1 are infrequent in DLBCL.
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http://dx.doi.org/10.1200/JCO.18.00766DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6528729PMC
February 2019

Management of Advanced and Relapsed/Refractory Extranodal Natural Killer T-Cell Lymphoma: An Analysis of Stem Cell Transplantation and Chemotherapy Outcomes.

Clin Lymphoma Myeloma Leuk 2018 01 12;18(1):e41-e50. Epub 2017 Oct 12.

Department of Lymphoma and Myeloma, The University of Texas M.D. Anderson Cancer Center, Houston, TX.

Background: Extra-Nodal natural killer/T-cell lymphoma (ENKL) is a rare lymphoma representing approximately 5-10% of T-cell non-Hodgkin lymphomas diagnosed in the United States each year. Patients with advanced stage III/IV ENKL and relapsed refractory ENKL have a poor prognosis even despite aggressive therapy and stem cell transplantation (SCT). We conducted a review of the management of 37 patients with advanced-stage and relapsed/refractory ENKL in a predominantly non-Asian cohort evaluating both chemotherapy and SCT outcomes.

Patients And Methods: We evaluated clinical outcomes in all patients treated for advanced stage III/IV or relapsed/refractory ENKL at MD Anderson cancer center between 2000-2014. Next, we collected stem cell transplant data from four transplant institutions to further evaluate outcomes of both allogeneic (allo-SCT) and autologous (auto-SCT) stem cell transplantation in ENKL.

Results: OS and PFS were 73% and 45% at one year, and 30% and 19% at 3-years, respectively. SMILE chemotherapy was more effective in maintaining a CR compared to CHOP (83% vs 17%). Only achievement of CR was prognostic for OS (HR 0.245, p=0.002) and PFS (HR 0.072, p) CONCLUSION: Our results suggest that achievement of a CR is imperative in patients with advanced ENKL, and is desirable for any patient for whom auto-SCT is utilized. SMILE-based chemotherapy appeared effective in attaining a CR, and was also an effective salvage regimen. For patients attaining a first CR, auto-SCT should be strongly considered, but should definitely be utilized in patients attaining CR2. For patients with refractory disease, allo-SCT can be considered in a selected group of patients.
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http://dx.doi.org/10.1016/j.clml.2017.10.001DOI Listing
January 2018

Extremely low high-density lipoprotein cholesterol (HDL) in a patient with diffuse B-cell lymphoma.

Pathology 2017 Aug 28;49(5):550-551. Epub 2017 Jun 28.

Department of Haematology-Oncology, National University Cancer Institute, Singapore.

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http://dx.doi.org/10.1016/j.pathol.2017.03.011DOI Listing
August 2017

Cloudless.

Authors:
Michelle P Poon

Med J Aust 2017 Jan;206(1):18

Maitland Hospital, Maitland, NSW

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http://dx.doi.org/10.5694/mja16.00674DOI Listing
January 2017

Future of Therapy in Acute Lymphoblastic Leukemia (ALL)--Potential Role of Immune-Based Therapies.

Curr Hematol Malig Rep 2015 Jun;10(2):76-85

Department of Stem Cell Transplantation and Cellular Therapy, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA,

The prognosis of acute lymphoblastic leukemia (ALL) in adults remains poor, and novel treatment options are needed to improve outcomes. Immunotherapeutic strategies have been a recent focus in this area, targeting specific surface antigens on the ALL blast cells. Our review concentrates on four major class of antibody therapies, namely, (1) naked and unconjugated antibodies, (2) immunoconjugates and immunotoxins, (3) bi-specific T cell engaging (BiTE) therapy, and (4) chimeric antigen receptor (CAR) expressing T cells. We review preclinical and clinical data, and update on the latest advances in this exciting field, and suggest how these therapies can be incorporated into the treatment algorithm for ALL.
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http://dx.doi.org/10.1007/s11899-015-0251-8DOI Listing
June 2015

WPSS is a strong prognostic indicator for clinical outcome of allogeneic transplant for myelodysplastic syndrome in Southeast Asian patients.

Ann Hematol 2015 May 18;94(5):761-9. Epub 2014 Dec 18.

Division of Hematology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.

To better understand the predictive factors and improve clinical outcome of allogeneic transplant for patients with myelodysplastic syndrome (MDS), we retrospectively analyzed the post-transplant outcome of 60 Southeast Asian patients with MDS. Multivariate analysis showed that WHO classification-based Prognostic Scoring System (WPSS) significantly affect overall survival (OS), progression-free survival (PFS), cumulative incidence of relapse (CIR), and cumulative incidence of non-relapse mortality (CINRM). Stratified by WPSS into very low/low, intermediate, high, and very high-risk categories, 3-year OS was 100, 61, 37, and 18% (p = 0.02); PFS was 100, 55, 32, and 18% (p = 0.014); CIR was 12, 24, 38, and 59% (p = 0.024); CINRM was 0, 6, 12, and 26% (p = 0.037), respectively. WHO classification, Revised International Prognostic Scoring System (IPSS-R), IPSS-R-defined cytogenetic risk groups, donor gender, and acute and chronic graft vs host disease (GVHD) also influenced different aspects of transplant outcome. We found that WPSS is a powerful predictor of post-transplant outcome. WPSS provides an important model not only for prognostication but also for exploration of further post-transplant measures such as immunological maneuvers or novel therapy to improve the poor outcome of high-risk patients.
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http://dx.doi.org/10.1007/s00277-014-2275-xDOI Listing
May 2015

Pre-transplant achievement of negativity in minimal residual disease and French-American-British L1 morphology predict superior outcome after allogeneic transplant for Philadelphia chromosome positive acute lymphoblastic leukemia: an analysis of Southeast Asian patients.

Leuk Lymphoma 2015 May 24;56(5):1362-9. Epub 2014 Oct 24.

Division of Hematology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine , Shanghai , People's Republic of China.

To better understand predictive factors and improve the clinical outcome of allogeneic transplant for patients with Philadelphia positive acute lymphoblastic leukemia, we analyzed 67 Southeast Asian patients transplanted in our institutions. Multivariate analysis showed that disease status before transplant, year of transplant and, interestingly, French-American-British (FAB) subtype had a significant impact on overall survival (OS) and non-relapse mortality. Patients who were minimal residual disease (MRD) negative at transplant had a 3-year OS of 73% compared to those who were MRD positive (45%) and refractory (0%). The 3-year cumulative incidence of relapse was 18% and 36% for the MRD negative and positive groups, respectively. FAB L1 subtype had a significantly superior 3-year OS of 63% vs. 29% for L2 subtype. Pre-transplant use of a tyrosine kinase inhibitor significantly improved outcomes in univariate but not multivariate analysis, as it served to induce more patients into MRD negativity, which was the factor that directly improved transplant outcome.
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http://dx.doi.org/10.3109/10428194.2014.956318DOI Listing
May 2015

Allogeneic stem cell transplant in patients with chronic lymphocytic leukemia with 17p deletion: consult-transplant versus consult- no-transplant analysis.

Leuk Lymphoma 2015 Mar 4;56(3):711-5. Epub 2014 Aug 4.

Department of Stem Cell Transplantation and Cellular Therapy.

Allogeneic stem cell transplant (alloSCT) can overcome the adverse prognosis of chronic lymphocytic leukemia with 17p deletion (17p- CLL). However, its applicability remains unclear. Since 2007, our leukemia service has referred patients with 17p- CLL for alloSCT at presentation. In this study, the outcomes of these patients were reviewed retrospectively to determine whether they underwent alloSCT and why patients did not undergo alloSCT. Fifty-two patients with 17p- CLL who were referred to the transplant service from 2007 to 2010 were identified. Of these patients, 32 (62%) did not undergo alloSCT, mainly because of treatment- or disease-related complications (n = 15). The 2-year post-referral overall survival rates of the alloSCT and non-SCT groups were 64% and 25%, respectively (p = 0.001). These findings suggest that while alloSCT is an effective therapy in patients with 17p- CLL, pre-SCT complications may preclude a significant proportion of patients from undergoing the procedure.
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http://dx.doi.org/10.3109/10428194.2014.930848DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4454336PMC
March 2015

Case report: cytomegalovirus-induced thrombosis in an immunocompetent patient.

J Med Virol 2012 Jan;84(1):116-8

Department of Hematology Oncology, National University Hospital, Singapore, Singapore.

Thrombotic manifestations of cytomegalovirus infection in immunocompetent individuals are rare. However, it has been postulated that cytomegalovirus infection can be both directly cytopathic and capable of inducing antiphospholipid antibodies due to shared "molecular mimicry" between cytomegalovirus virus antigens and antiphospholipid antibodies. The case of a previously well 30-year-old woman with primary cytomegalovirus infection complicated by splenic infarction and massive pulmonary embolus is described. The patient is unusual given the development of thromboses affecting both the arterial and venous circulation, associated with both transient anticardiolipin antibodies and persistently positive anti-β(2) glycoprotein I antibodies. The temporal relationship between the primary infection and thrombosis was suggestive of a pathogenic role for cytomegalovirus.
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http://dx.doi.org/10.1002/jmv.22253DOI Listing
January 2012

Spontaneous Pneumothorax in an Allogeneic Cell Transplant Recipient with Invasive Pulmonary Aspergillosis and Antecedent RSV Pneumonitis.

Mediterr J Hematol Infect Dis 2011 1;3(1):e20110. Epub 2011 Apr 1.

Departments of Hematology-Oncology.

We report a case of invasive pulmonary aspergillosis (IPA) following respiratory syncytial virus infection in an allogeneic hematopoietic stem cell transplant (HSCT) recipient with chronic graft-versus-host disease. Delayed diagnosis of IPA resulted in the development of a pneumothorax, a rare consequence of fungal pneumonia. Respiratory virus infections are often harbingers of other infective organisms in HSCT recipients. More aggressive diagnostic investigations such as computed tomography scans of the thorax and bronchoscopy with bronchoalveolar lavage should be considered early in any HSCT patient presenting with respiratory virus pneumonia, particularly if atypical features are present or recovery is delayed.
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http://dx.doi.org/10.4084/mjhid.2011.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3103259PMC
July 2011

Hereditary thrombophilia in an unselected cohort of venous thrombosis patients in Singapore.

J Clin Pathol 2011 Sep 18;64(9):814-7. Epub 2011 May 18.

Department of Haematology, Singapore General Hospital, Singapore.

Aim: Hereditary thrombophilic markers are commonly screened among patients diagnosed as having venous thromboembolism, but optimal patient selection and the goals of screening may differ between populations. Determining the patterns of hereditary thrombophilia may improve screening strategies.

Method: An unselected cohort of venous thromboembolism patients in three tertiary institutions in Singapore was prospectively tested for the prevalence of deficiencies of protein C, protein S, antithrombin III, factor V Leiden and prothrombin 20210 gene mutations.

Results: Among 384 patients screened, the prevalences of protein S, protein C and antithrombin III were 9.20%, 1.18% and 4.19% respectively. Only one patient was positive for the factor V Leiden mutation and none tested positive for the prothrombin 20210 gene mutation. At least 1 in 9 patients (11.52%, 95% CI 8.20 to 15.93) will test positive for one of the above markers in an unselected group of 269 patients who completed all tests. The exclusion of patients with clinical risk factors did not improve the detection rates, in comparison with those with obvious provoking clinical risk factors (11.72%, 95% CI 7.36 to 18.06 vs 11.29%, 95% CI 6.73 to 18.18). When upper age limits were set for thrombophilia screening by decades, a statistical difference in the likelihood of a positive thrombophilia screen between younger and older patient was seen for patients below 40 (p<0.001).

Conclusion: In Singapore and countries with similar demographics, hereditary thrombophilia screening should be confined to testing for protein C, protein S and antithrombin III.
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http://dx.doi.org/10.1136/jclinpath-2011-200018DOI Listing
September 2011

Primary cutaneous anaplastic large cell lymphoma of the vulva: a typical cutaneous lesion with an 'atypical' presenting site.

Int J Hematol 2009 Oct 26;90(3):388-391. Epub 2009 Aug 26.

Department of Obstetrics and Gynaecology, National University Hospital, Singapore, Singapore.

Non-Hodgkin lymphoma of vulva is exceedingly rare and it often poses a diagnostic challenge if their existence is not suspected. We report a patient who has primary cutaneous anaplastic large cell (C-ALCL) with an unusual presentation as a vulvar ulcer. She received a brief course of chemotherapy followed by local irradiation and has remained disease-free more than a year from the time of diagnosis. To our knowledge, primary C-ALCL involving the vulva has never been reported. Despite its typical cutaneous manifestation of C-ALCL, the uncommon presenting site of this entity warrants recognition because of its prognostic and therapeutic implication.
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http://dx.doi.org/10.1007/s12185-009-0395-1DOI Listing
October 2009