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result(s) for
"Patel, Keyur P."
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Mutually exclusive recurrent KRAS and MAP2K1 mutations in Rosai–Dorfman disease
by
Patel, Keyur P
,
Li, Shaoying
,
Pina-Oviedo, Sergio
in
692/53/2421
,
692/699/1541/1990/291/1621/1916
,
Adolescent
2017
Rosai–Dorfman disease is a histiocytic disorder with a poorly defined pathogenesis. Recent molecular studies have revealed recurrent mutations involving genes in the MAPK/ERK pathway in Langerhans cell histiocytosis and Erdheim–Chester disease. However, cases of Rosai–Dorfman disease have rarely been assessed. We performed next-generation sequencing to assess 134 genes on 21 cases of Rosai–Dorfman disease, including 13 women and 8 men with a median age of 43 years (range, 3–82). In all, 13 had extranodal, 5 had nodal, and 3 had coexistent nodal and extranodal disease. The head and neck region was the most common area involved (
n
=7). Mutation analysis detected point mutations in 7 (33%) cases, including
KRAS
(
n
=4) and
MAP2K1
(
n
=3). No mutations were identified in
ARAF
,
BRAF
,
PIK3CA
, or any other genes assessed. Immunohistochemistry demonstrated p-ERK overexpression in 3 cases, all harboring
MAP2K1
mutations. Patients carrying mutated genes were younger (median age, 10
vs
53 years,
P
=0.0347) with more pediatric patients (4/7
vs
1/14,
P
=0.0251). The presence of mutations correlated with location being more common in the head and neck region; 6/7 (86%) mutated
vs
1/14 (7%) unmutated cases (
P
=0.0009). All 5 (100%) mutated cases with available staging information had a multifocal presentation, whereas only 3/11 (27%) unmutated patients had multifocal disease (
P
=0.0256). Treatment information was available in 10 patients, including radical resection (
n
=4), resection and radiation (
n
=3), and cladribine-based chemotherapy (
n
=3). With a median follow-up of 84 months (range, 7–352), 7 remained in clinical remission and 3 had persistent disease. No correlation between mutation status and clinical outcome was noted. In summary, we detected mutually exclusive
KRAS
and
MAP2K1
mutations in one-third of cases of Rosai–Dorfman disease suggesting this subgroup are clonal and involve activation of MAPK/ERK pathway. Our data contribute to the understanding of the biology of Rosai–Dorfman disease and point to potential diagnostic and therapeutic targets.
Journal Article
Prognostic and therapeutic implications of measurable residual disease in acute myeloid leukemia
by
Short, Nicholas J.
,
Aitken, Marisa J. L.
,
Patel, Keyur P.
in
Acute myeloid leukemia
,
Antigens
,
Cancer
2021
Quantification of measurable residual disease (MRD) provides critical prognostic information in acute myeloid leukemia (AML). A variety of platforms exist for MRD detection, varying in their sensitivity and applicability to individual patients. MRD detected by quantitative polymerase chain reaction, multiparameter flow cytometry, or next-generation sequencing has prognostic implications in various subsets of AML and at various times throughout treatment. While it is overwhelmingly evident that minute levels of remnant disease confer increased risk of relapse and shortened survival, the therapeutic implications of MRD remain less clear. The use of MRD as a guide to selecting the most optimal post-remission therapy, including hematopoietic stem cell transplant or maintenance therapy with hypomethylating agents, small molecule inhibitors, or immunotherapy is an area of active investigation. In addition, whether there are sufficient data to use MRD negativity as a surrogate endpoint in clinical trial development is controversial. In this review, we will critically examine the methods used to detect MRD, its role as a prognostic biomarker, MRD-directed therapeutics, and its potential role as a study endpoint.
Journal Article
Sample-to-answer, extraction-free, real-time RT-LAMP test for SARS-CoV-2 in nasopharyngeal, nasal, and saliva samples: Implications and use for surveillance testing
2022
The global COVID-19 pandemic has highlighted the need for rapid, accurate and accessible nucleic acid tests to enable timely identification of infected individuals. We optimized a sample-to-answer nucleic acid test for SARS-CoV-2 that provides results in <1 hour using inexpensive and readily available reagents. The test workflow includes a simple lysis and viral inactivation protocol followed by direct isothermal amplification of viral RNA using RT-LAMP. The assay was validated using two different instruments, a portable isothermal fluorimeter and a standard thermocycler. Results of the RT-LAMP assay were compared to traditional RT-qPCR for nasopharyngeal swabs, nasal swabs, and saliva collected from a cohort of patients hospitalized due to COVID-19. For all three sample types, positive agreement with RT-LAMP performed using the isothermal fluorimeter was 100% for samples with Ct <30 and 69–91% for samples with Ct <40. Following validation, the test was successfully scaled to test the saliva of up to 400 asymptomatic individuals per day as part of the campus surveillance program at Rice University. Successful development, validation, and scaling of this sample-to-answer, extraction-free real-time RT-LAMP test for SARS-CoV-2 adds a highly adaptable tool to efforts to control the COVID-19 pandemic, and can inform test development strategies for future infectious disease threats.
Journal Article
Clinical utility of recently identified diagnostic, prognostic, and predictive molecular biomarkers in mature B-cell neoplasms
by
Patel, Keyur P
,
Medeiros, L Jeffrey
,
Onaindia, Arantza
in
692/53/2421
,
692/53/2422
,
692/53/2423
2017
Genomic profiling studies have provided new insights into the pathogenesis of mature B-cell neoplasms and have identified markers with prognostic impact. Recurrent mutations in tumor-suppressor genes (
TP53, BIRC3, ATM
), and common signaling pathways, such as the B-cell receptor (
CD79A
,
CD79B
,
CARD11
,
TCF3, ID3
), Toll-like receptor (
MYD88
), NOTCH (
NOTCH1/2
), nuclear factor-
κ
B, and mitogen activated kinase signaling, have been identified in B-cell neoplasms. Chronic lymphocytic leukemia/small lymphocytic lymphoma, diffuse large B-cell lymphoma, follicular lymphoma, mantle cell lymphoma, Burkitt lymphoma, Waldenström macroglobulinemia, hairy cell leukemia, and marginal zone lymphomas of splenic, nodal, and extranodal types represent examples of B-cell neoplasms in which novel molecular biomarkers have been discovered in recent years. In addition, ongoing retrospective correlative and prospective outcome studies have resulted in an enhanced understanding of the clinical utility of novel biomarkers. This progress is reflected in the 2016 update of the World Health Organization classification of lymphoid neoplasms, which lists as many as 41 mature B-cell neoplasms (including provisional categories). Consequently, molecular genetic studies are increasingly being applied for the clinical workup of many of these neoplasms. In this review, we focus on the diagnostic, prognostic, and/or therapeutic utility of molecular biomarkers in mature B-cell neoplasms.
Journal Article
Concurrent fine needle aspirations and core needle biopsies: a comparative study of substrates for next-generation sequencing in solid organ malignancies
by
Singh, Rajesh R
,
Luthra, Rajyalakshmi
,
Medeiros, L Jeffrey
in
692/699/67
,
692/700/139/422
,
Adrenal glands
2017
Minimally invasive procedures, such as fine needle aspiration and core needle biopsy, are commonly used for the diagnosis in solid organ malignancies. In the era of targeted therapy, it is crucial for molecular testing to be performed on these limited volume specimens. Although several recent studies have demonstrated the utility of small biopsy specimens for molecular testing, there remains debate as to whether core needle biopsy specimens are more reliable than fine needle aspiration for molecular studies. In this study, we reviewed concurrently acquired fine needle aspiration and core needle biopsy samples (n=24), and compared overall cellularity, tumor fraction, and the results of next-generation sequencing. All somatic mutations detected in core needle biopsy samples were also detected in fine needle aspiration samples. The estimated tumor fraction was significantly higher in fine needle aspiration smears than core needle biopsy samples (P=0.003), whereas the overall DNA yield from smears was significantly lower than that obtained from the core needle biopsy specimens (P=0.01). The normalized average amplicon coverage for the genes analyzed was significantly higher in cytology smears than paired core needle biopsy samples, with lower numbers of failed amplicons and higher overall mutation allelic frequencies seen in the former. We further evaluated 100 malignant fine needle aspiration and core needle biopsy samples, acquired concurrently, for overall cellularity and tumor fraction. Overall cellularity and tumor fraction of fine needle aspiration samples was significantly higher than concurrently acquired core needle biopsy samples (P<0.001). In conclusion, we show that fine needle aspiration samples frequently provide better cellularity, higher tumor fraction, and superior sequencing metrics than concurrently acquired core needle biopsy samples. Cytologic specimens, therefore, should be better integrated into routine molecular diagnostics workflow to maximize limited tissues for clinically relevant genomic testing.
Journal Article
Association of SMAD4 mutation with patient demographics, tumor characteristics, and clinical outcomes in colorectal cancer
2017
SMAD4 is an essential mediator in the transforming growth factor-β pathway. Sporadic mutations of SMAD4 are present in 2.1-20.0% of colorectal cancers (CRCs) but data are limited. In this study, we aimed to evaluate clinicopathologic characteristics, prognosis, and clinical outcome associated with this mutation in CRC cases. Data for patients with metastatic or unresectable CRC who underwent genotyping for SMAD4 mutation and received treatment at The University of Texas MD Anderson Cancer Center from 2000 to 2014 were reviewed. Their tumors were sequenced using a hotspot panel predicted to cover 80% of the reported SMAD4 mutations, and further targeted resequencing that included full-length SMAD4 was performed on mutated tumors using a HiSeq sequencing system. Using The Cancer Genome Atlas data on CRC, the characteristics of SMAD4 and transforming growth factor-β pathway mutations were evaluated according to different consensus molecular subtypes of CRC. Among 734 patients with CRC, 90 (12%) had SMAD4 mutations according to hotspot testing. SMAD4 mutation was associated with colon cancer more so than with rectal cancer (odds ratio 2.85; p<0.001), female sex (odds ratio 1.71; p = 0.02), and shorter overall survival than in wild-type SMAD4 cases (median, 29 months versus 56 months; hazard ratio 2.08; p<0.001 [log-rank test]). SMAD4 mutation was not associated with age, stage at presentation, colonic location, distant metastasis, or tumor grade. A subset of patients with metastatic CRC (n = 44) wild-type for KRAS, NRAS, and BRAF who received anti-epidermal growth factor receptor therapy with mutated SMAD4 (n = 13) had shorter progression-free survival duration than did patients wild-type for SMAD4 (n = 31) (median, 111 days versus 180 days; p = 0.003 [log-rank test]). Full-length sequencing confirmed that missense mutations at R361 and P356 in the MH2 domain were the most common SMAD4 alterations. In The Cancer Genome Atlas data, SMAD4 mutation frequently occurred with KRAS, NRAS, and BRAF mutations and was more common in patients with the consensus molecular subtype 3 of CRC than in those with the other 3 subtypes. This is one of the largest retrospective studies to date characterizing SMAD4 mutations in CRC patients and demonstrates the prognostic role and lack of response of CRC to anti-epidermal growth factor receptor therapy. Further studies are required to validate these findings and the role of SMAD4 mutation in CRC.
Journal Article
Next-generation sequencing-based multi-gene mutation profiling of solid tumors using fine needle aspiration samples: promises and challenges for routine clinical diagnostics
by
Singh, Rajesh R
,
Luthra, Rajyalakshmi
,
Mishra, Bal M
in
631/208/514/2254
,
692/700/139/1512
,
692/700/139/422
2014
Increasing use of fine needle aspiration for oncological diagnosis, while minimally invasive, poses a challenge for molecular testing by traditional sequencing platforms due to high sample requirements. The advent of affordable benchtop next-generation sequencing platforms such as the semiconductor-based Ion Personal Genome Machine (PGM) Sequencer has facilitated multi-gene mutational profiling using only nanograms of DNA. We describe successful next-generation sequencing-based testing of fine needle aspiration cytological specimens in a clinical laboratory setting. We selected 61 tumor specimens, obtained by fine needle aspiration, with known mutational status for clinically relevant genes; of these, 31 specimens yielded sufficient DNA for next-generation sequencing testing. Ten nanograms of DNA from each sample was tested for mutations in the hotspot regions of 46 cancer-related genes using a 318-chip on Ion PGM Sequencer. All tested samples underwent successful targeted sequencing of 46 genes. We showed 100% concordance of results between next-generation sequencing and conventional test platforms for all previously known point mutations that included BRAF, EGFR, KRAS, MET, NRAS, PIK3CA, RET and TP53, deletions of EGFR and wild-type calls. Furthermore, next-generation sequencing detected variants in 19 of the 31 (61%) patient samples that were not detected by traditional platforms, thus increasing the utility of mutation analysis; these variants involved the APC, ATM, CDKN2A, CTNNB1, FGFR2, FLT3, KDR, KIT, KRAS, MLH1, NRAS, PIK3CA, SMAD4, STK11 and TP53 genes. The results of this study show that next-generation sequencing-based mutational profiling can be performed on fine needle aspiration cytological smears and cell blocks. Next-generation sequencing can be performed with only nanograms of DNA and has better sensitivity than traditional sequencing platforms. Use of next-generation sequencing also enhances the power of fine needle aspiration by providing gene mutation results that can direct personalized cancer therapy.
Journal Article
Predictors of outcomes in adults with acute myeloid leukemia and KMT2A rearrangements
2021
Acute myeloid leukemia (AML) with rearrangement of the lysine methyltransferase 2a gene (KMT2Ar) has adverse outcomes. However, reports on the prognostic impact of various translocations causing KMT2Ar are conflicting. Less is known about associated mutations and their prognostic impact. In a retrospective analysis, we identified 172 adult patients with KMT2Ar AML and compared them to 522 age-matched patients with diploid AML. KMT2Ar AML had fewer mutations, most commonly affecting RAS and FLT3 without significant impact on prognosis, except for patients with ≥2 mutations with lower overall survival (OS). KMT2Ar AML had worse outcomes compared with diploid AML when newly diagnosed and at relapse, especially following second salvage (median OS of 2.4 vs 4.8 months, P < 0.0001). Therapy-related KMT2Ar AML (t-AML) had worse outcomes compared with de novo KMT2Ar AML (median OS of 0.7 years vs 1.4 years, P < 0.0001). Allogeneic hematopoietic stem cell transplant (allo-HSCT) in first remission was associated with improved OS (5-year, 52 vs 14% for no allo-HSCT, P < 0.0001). In a multivariate analysis, translocation subtypes causing KMT2Ar did not predict survival, unlike age and allo-HSCT. In conclusion, KMT2Ar was associated with adverse outcomes regardless of translocation subtype. Therefore, AML risk stratification guidelines should include all KMT2Ar as adverse.
Journal Article
A phase 1/2 study of azacitidine, venetoclax and pevonedistat in newly diagnosed secondary AML and in MDS or CMML after failure of hypomethylating agents
by
Kantarjian, Hagop
,
Borthakur, Gautam
,
Jain, Nitin
in
Acute myeloid leukemia
,
Aged
,
Aged, 80 and over
2023
Background
Pevonedistat is a first-in-class, small molecular inhibitor of NEDD8-activating enzyme that has clinical activity in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Preclinical data suggest synergy of pevonedistat with azacitidine and venetoclax.
Methods
This single-center, phase 1/2 study evaluated the combination of azacitidine, venetoclax and pevonedistat in older adults with newly diagnosed secondary AML or with MDS or chronic myelomonocytic leukemia (CMML) after failure of hypomethylating agents. Patients received azacitidine 75 mg/m
2
IV on days 1–7, venetoclax at maximum dose of 200-400 mg orally on days 1–21 (AML cohort) or days 1–14 (MDS/CMML cohort) and pevonedistat 20 mg/m
2
IV on days 1, 3 and 5 for up to 24 cycles. The primary endpoints for the phase 2 portion of the study were the CR/CRi rate in the AML cohort and the overall response rate (CR + mCR + PR + HI) in the MDS/CMML cohort.
Findings
Forty patients were enrolled (32 with AML and 8 with MDS/CMML). In the AML cohort, the median age was 74 years (range 61–86 years), and 27 patients (84%) had at least one adverse risk cyto-molecular feature, including 15 (47%) with a
TP53
mutation or
MECOM
rearrangement; seventeen patients (53%) had received prior therapy for a preceding myeloid disorder. The CR/CRi rate was 66% (CR 50%; CRi 16%), and the median overall survival (OS) was 8.1 months. In the MDS/CMML cohort, 7 patients (87%) were high or very high risk by the IPSS-R. The overall response rate was 75% (CR 13%; mCR with or without HI 50%; HI 13%). The most common grade 3–4 adverse events were infection in 16 patients (35%), febrile neutropenia in 10 patients (25%) and hypophosphatemia in 9 patients (23%). In an exploratory analysis, early upregulation of NOXA expression was observed, with subsequent decrease in MCL-1 and FLIP, findings consistent with preclinical mechanistic studies of pevonedistat. Upregulation of CD36 was observed, which may have contributed to therapeutic resistance.
Conclusions
The triplet combination of azacitidine, venetoclax and pevonedistat shows encouraging activity in this very poor-risk population of patients with AML, MDS or CMML.
Trial registration
ClinicalTrials.gov (NCT03862157).
Journal Article
Identification of Factors Affecting the Success of Next-Generation Sequencing Testing in Solid Tumors
by
Dang, Hyvan D.
,
Luthra, Rajyalakshmi
,
Patel, Keyur P.
in
Biomarkers, Tumor - genetics
,
DNA Mutational Analysis
,
DNA, Neoplasm - analysis
2016
Objectives: Clinical laboratories are rapidly implementing next-generation sequencing (NGS) tests for mutation analysis, but there are few guidelines regarding sample quality for successful results.
Methods: We aimed to establish tissue quality parameters for successful NGS in solid tumors and to improve NGS performance.
Results: Analysis of 614 clinical cases tested in 2013 using a 50-gene hotspot mutation panel identified the major cause for unsuccessful NGS analysis was DNA less than 10 ng (91%, 67/74) associated with extremely small and low cellularity samples. High success rates were associated with resection procedures (333/342, 97%) and biopsied tumor larger than 10 mm2 (77/77, 100%). NGS can be successfully performed on bone specimens processed with formic acid–based decalcification procedures (8/11, 73%). Tumor type and paraffin block age did not affect success. We demonstrated that NGS can be carried out on samples with less than 10 ng DNA. Analysis of 408 cases tested in 2014 using an optimized workflow showed improved NGS success rates from 88% to 95% (387/408) with pronounced improvement among tiny (<10 mm2) samples (from 76% to 94%) as well as cytology samples (from 58% to 87%).
Conclusions: Identifying preanalytical tissue factors allows us to improve NGS performance and to successfully test tumors obtained from minimally invasive procedures.
Journal Article