Publications by authors named "Saud Azam"

11 Publications

  • Page 1 of 1

Clonal Evolution and Timing of Metastatic Colorectal Cancer.

Cancers (Basel) 2020 Oct 12;12(10). Epub 2020 Oct 12.

Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.

Colorectal cancer (CRC) is the third most frequently diagnosed cancer worldwide, where ~50% of patients develop metastasis, despite current improved management. Genomic characterisation of metastatic CRC, and elucidating the effects of therapy on the metastatic process, are essential to help guide precision medicine. Multi-region whole-exome sequencing was performed on 191 sampled tumour regions of patient-matched therapy-naïve and treated CRC primary tumours ( = 92 tumour regions) and metastases ( = 99 tumour regions), in 30 patients. Somatic variants were analysed to define the origin, composition, and timing of seeding in the metastatic progression of therapy-naïve and treated metastatic CRC. High concordance, with few genomic differences, was observed between primary CRC and metastases. Most cases supported a late dissemination model, via either monoclonal or polyclonal seeding. Polyclonal seeding appeared more common in therapy-naïve metastases than in treated metastases. Whereby, treatment prompted for the selection of distinct resistant clones, through monoclonal seeding to distant metastatic sites. Overall, this study reinforces the importance of early clinical detection and surgical excision of the CRC tumour, whilst further highlighting the clinical challenges for metastatic CRC with increased intratumour heterogeneity (either due to early dissemination or polyclonal metastatic spread) and the underlying risk of future therapeutic resistance in treated patients.
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http://dx.doi.org/10.3390/cancers12102938DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7601934PMC
October 2020

Genetic heterogeneity and evolutionary history of high-grade ovarian carcinoma and matched distant metastases.

Br J Cancer 2020 04 26;122(8):1219-1230. Epub 2020 Feb 26.

Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, Riyadh, 11211, Saudi Arabia.

Background: High-grade serous ovarian carcinoma (HGSOC) is the most frequent type of ovarian carcinoma, associated with poor clinical outcome and metastatic disease. Although metastatic processes are becoming more understandable, the genomic landscape and metastatic progression in HGSOC has not been elucidated.

Methods: Multi-region whole-exome sequencing was performed on HGSOC primary tumours and their metastases (n = 33 tumour regions) from six patients. The resulting somatic variants were analysed to delineate tumour evolution and metastatic dissemination, and to compare the repertoire of events between primary HGSOC and metastasis.

Results: All cases presented branching evolution patterns in primary HGSOC, with three cases further showing parallel evolution in which different mutations on separate branches of a phylogenetic tree converge on the same gene. Furthermore, linear metastatic progression was observed in 67% of cases with late dissemination, in which the metastatic tumour mostly acquires the same mutational process active in primary tumour, and parallel metastatic progression, with early dissemination in the remaining 33.3% of cases. Metastatic-specific SNVs were further confirmed as late dissemination events. We also found the involvement of metastatic-specific driver events in the Wnt/β-catenin pathway, and identified potential clinically actionable events in individual patients of the metastatic HGSOC cohort.

Conclusions: This study provides deeper insights into clonal evolution and mutational processes that can pave the way to new therapeutic targets.
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http://dx.doi.org/10.1038/s41416-020-0763-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7156387PMC
April 2020

Evolution and Impact of Subclonal Mutations in Papillary Thyroid Cancer.

Am J Hum Genet 2019 11 24;105(5):959-973. Epub 2019 Oct 24.

Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Centre, PO Box 3354, Riyadh 11211, Saudi Arabia. Electronic address:

Unlike many cancers, the pattern of tumor evolution in papillary thyroid cancer (PTC) and its potential role in relapse have not been elucidated. In this study, multi-region whole-exome sequencing (WES) was performed on early-stage PTC tumors (n = 257 tumor regions) from 79 individuals, including 17 who had developed relapse, to understand the temporal and spatial framework within which subclonal mutations catalyze tumor evolution and its potential clinical relevance. Paired primary-relapse tumor tissues were also available for a subset of individuals. The resulting catalog of variants was analyzed to explore evolutionary histories, define clonal and subclonal events, and assess the relationship between intra-tumor heterogeneity and relapse-free survival. The multi-region WES approach was key in correctly classifying subclonal mutations, 40% of which would have otherwise been erroneously considered clonal. We observed both linear and branching evolution patterns in our PTC cohort. A higher burden of subclonal mutations was significantly associated with increased risk of relapse. We conclude that relapse in PTC, while generally rare, does not follow a predictable evolutionary path and that subclonal mutation burden may serve as a prognostic factor. Larger studies utilizing multi-region sequencing in relapsed PTC case subjects with matching primary tissues are needed to confirm these observations.
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http://dx.doi.org/10.1016/j.ajhg.2019.09.026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6849094PMC
November 2019

Whole-Exome Sequencing of Matched Primary and Metastatic Papillary Thyroid Cancer.

Thyroid 2020 01 4;30(1):42-56. Epub 2019 Dec 4.

Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia.

Distant metastasis is a rare occurrence in thyroid cancer, and it can be associated with poor prognosis. The genomic repertoires of various solid malignancies have previously been reported but remain underexplored in metastatic papillary thyroid cancer (PTC). Furthermore, whether distant metastases harbor distinct genetic alterations beyond those observed in primary tumors is unknown. We performed whole-exome sequencing on 14 matched distant metastases, primary PTC tumors, and normal tissues. Point mutations, copy number alterations, cancer cell fractions, and mutational signatures were defined using the state-of-the-art bioinformatics methods. All likely deleterious variants were validated by orthogonal methods. Genomic differences were observed between primary and distant metastatic deposits, with a median of 62% (range 21-92%) of somatic mutations detected in metastatic tissues, but absent from the corresponding primary tumor sample. Mutations in known driver genes including , , and were shared and preferentially clonal in both sites. However, likely deleterious variants affecting DNA methylation and transcriptional repression signaling genes including , , and were found to be restricted in the metastatic lesions. Moreover, a mutational signature shift was observed between the mutations that are specific or enriched in the metastatic and primary lesions. Primary PTC and distant metastases differ in their range of somatic alterations. Genomic analysis of distant metastases provides an opportunity to identify potentially clinically informative alterations not detected in primary tumors, which might influence decisions for personalized therapy in PTC patients with distant metastasis.
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http://dx.doi.org/10.1089/thy.2019.0052DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6983753PMC
January 2020

Prevalence and distribution of soil-transmitted helminth infections in India.

BMC Public Health 2017 02 16;17(1):201. Epub 2017 Feb 16.

Innova-CRO, Riyadh, Saudi Arabia.

Background: Understanding the prevalence of soil-transmitted helminth infections is necessary to plan control strategies and focus on highly endemic regions for preventive chemotherapy and improved sanitation facilities. India is known to be endemic for soil-transmitted helminth infections.

Methods: To understand the prevalence, spatial distribution and identify high-risk zones, a systematic search of published literature was carried out based on PRISMA guidelines from the year 2000 to 2015.

Results: A careful screening of the identified literature yielded 39 studies that reported the prevalence of soil-transmitted helminth infections from 19 different states of India. Ascaris lumbricoides was the most prevalent parasite. Higher than 50% prevalence was reported from six states. Nearly 90% studies reported the prevalence of more than one parasite species in the same sample population.

Conclusion: This is the first study to comprehensively review the literature associated with soil-transmitted helminth infections from India giving a clear idea of its prevalence, distribution and high endemic areas.
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http://dx.doi.org/10.1186/s12889-017-4113-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5311856PMC
February 2017

Eight Year Survival Analysis of Patients with Triple Negative Breast Cancer in India.

Asian Pac J Cancer Prev 2016 ;17(6):2995-9

Department of Medical Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India E-mail :

Background: Triple-negative breast cancer (TNBC) often presents as an interval cancer with short survival upon metastasis and thus represents an important clinical challenge. The present study investigated the clinicopathologic characteristics and long term survival outcome of early and locally advanced TNBC.

Materials And Methods: Medical records were reviewed retrospectively for 148 consecutive confirmed cases of TNBC treated in a single unit at our centre. Demographic profile, tumor type, histopathology details, treatment and follow-up information was recorded and immunohistochemistry was performed.

Results: Age group >50 years was associated with tumors of clinical stage 3 (53.8%), pathological stage 3 (46.2%), pathological grade 3 (45.7%), presence of extracapsular extension (ECE, 48.5%) and lymphovascular invasion (LVI, 64.9%). Locally advanced breast cancers (LABCs) were characterized by pathological stage 3 (96.2%), presence of ECE (100%) and absence of LVI (46.7%) as compared to early breast cancers (EBCs) which had higher incidence of lower stage tumors (100%), absence of ECE (82%) and presence of LVI (91.9%; p-value <0.001. Better relapse free survival was observed in patients with no axillary involvement (69%; p-value <0.001) and absence of ECE (64%; p-value <0.001). Improved overall survival was seen in patients with EBC (90%; p-value 0.008), clear axilla (86%; p-value <0.001), absence of ECE (87%; p-value <0.001) and negative lymph nodes (90%; p-value 0.006).

Conclusions: TNBCs are aggressive tumors which show poor long term survival. Patients with TNBC benefit from chemotherapy, thus better and less toxic treatment options are needed. Identification of newer targets and development of targeted therapies are the need of the hour.
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January 2017

A Report of Two Cases of Leptomeningeal Carcinomatosis Arising from Gallbladder Carcinoma.

J Gastrointest Cancer 2015 Dec;46(4):417-20

Department of Radiology, Rajiv Gandhi Cancer Institute & Research Centre, Delhi, India.

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http://dx.doi.org/10.1007/s12029-015-9719-yDOI Listing
December 2015

A report of sarcomatoid carcinoma of the gallbladder treated with palliative deocetaxel and gemcitabine chemotherapy.

J Gastrointest Cancer 2014 Dec;45 Suppl 1:270-4

Department of Medical Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Sector 5, Rohini, Delhi, 110085, India,

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http://dx.doi.org/10.1007/s12029-014-9654-3DOI Listing
December 2014

Expression of epidermal growth factor receptor, p53, Bcl2, vascular endothelial growth factor, cyclooxygenase-2, cyclin D1, human epidermal receptor-2 and Ki-67: Association with clinicopathological profiles and outcomes in gallbladder carcinoma.

J Carcinog 2014 25;13:10. Epub 2014 Aug 25.

Department of Laboratory Services, Rajiv Gandhi Cancer Institute and Research Centre, New Delhi, India.

Background: The present study observed the expression levels of epidermal growth factor receptor (EGFR), p53, Bcl2, vascular endothelial growth factor (VEGF), cyclooxygenase-2 (cox-2), cyclin D1, human epidermal receptor-2 (HER-2) and Ki-67 in gallbladder carcinoma (GBC) and their association with clinicopathological profiles and disease outcomes.

Materials And Methods: Fifty consecutive samples of cholecystectomy/biopsies from GB bed (archived formalin fixed paraffin embedded tissue blocks of different stages of GBC) were included, and patient details related to their demographic profile, investigations, tumor profile, treatment, and follow-up were recorded. Immunohistochemistry was performed to study the expression levels.

Results: Overexpression of EGFR, p53, Bcl2, VEGF, cox-2, cyclin D1 and HER-2 was observed as 74%, 44%, 8%, 34%, 66%, 64%, and 4%, respectively. Association of Bcl2 overexpression in mucinous morphology (40%, P = 0.045), cox-2 overexpression in early stage (I/II) tumors (87.5%, P = 0.028) and VEGF overexpression in alive patients (47.1%, P = 0.044) was observed. Co-expression of EGFR and p53 were statistically significant (P = 0.033). Ki-67 labeling index was significantly higher in patients in age group <40 years (P = 0.027), and poorly differentiated tumors (P = 0.023). Advanced disease and poorly differentiated tumors showed a significantly poor median survival (P < 0.05).

Conclusion: EGFR, cox-2 and cyclin D1 were largely overexpressed. Advanced tumor stages and poorly differentiated tumors are predictors of poor survival.
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http://dx.doi.org/10.4103/1477-3163.139450DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4163917PMC
September 2014

Chronic myeloid leukemia treatment with Imatinib: An experience from a private tertiary care hospital.

Indian J Med Paediatr Oncol 2013 Jul;34(3):182-5

Department of Medical Oncology and Research, Rajiv Gandhi Cancer Institute and Research Centre, Rohini, New Delhi, India.

The data presents 75 chronic myeloid leukemia patients diagnosed over a period 6 years i.e. from 2002 to 2008. The most common presentation was splenomegaly and 97% achieved complete hematological response at median duration of 4.3 weeks. The uniqueness of this study is follow-up with molecular response monitoring. Nearly, 30% patients achieved major molecular response (MMoR) by 12 months. 70% of patients achieved MMoR by median time of 60 months. Only 10% of the patient who achieved MMoR by 18 months had lost their responses subsequently.
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http://dx.doi.org/10.4103/0971-5851.123725DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3902620PMC
July 2013

Epidermal growth factor receptor mutation in lung adenocarcinoma in India: A single center study.

J Carcinog 2013 12;12:12. Epub 2013 Jul 12.

Department of Medical Oncology, Research, Rajiv Gandhi Cancer Institute and Research Centre, New Delhi, India ; Department of Research, Rajiv Gandhi Cancer Institute and Research Centre, New Delhi, India.

Background: Adenocarcinoma, a subgroup of non-small cell lung cancer, is the most frequent form occurring in the non-smokers. Mutation in tyrosine kinase domain of epidermal growth factor receptor (EGFR) has been a common feature observed in lung adenocarcinoma. The study was carried out to detect the prevalence of EGFR mutation in lung adenocarcinoma.

Materials And Methods: EGFR mutation status in 166 lung adenocarcinoma patients was obtained retrospectively. Mutation tests were performed on paraffin embedded tissue blocks as a routine diagnostic procedure by polymerase chain reaction followed by direct nucleotide sequencing. Patient's demographics and other clinical details were obtained from the medical records.

Results: EGFR mutation was detected in 43/166 (25.9%) patients. Gender wise mutation was observed as 18/55 (32.7%) in females and 25/111 (22.5%) in males. Overall, EGFR mutation was correlated with never smokers and distant metastasis (P < 0.05), but not associated with the gender, disease stage and pleural effusion. Exon 19 deletions were significantly correlated with females, never smokers, pleural effusion and distant metastasis (P < 0.05). However, point mutation on exon 21 did not show any statistical association with the above variables. Median overall survival was 22 months (95% confidence interval, 15.4-28.6). Female sex, EGFR mutation and absence of metastasis are associated with good prognosis.

Conclusion: EGFR mutation in lung adenocarcinoma was higher in never smokers, females and patients with distant metastasis. However, it was not linked with tobacco smoking. The prevalence of EGFR mutation observed is in range with the previously published reports from the Asian countries.
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http://dx.doi.org/10.4103/1477-3163.114970DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3746453PMC
August 2013