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Yadav, Siddhartha

0000-0003-4630-9903

Mayo Clinic

Mayo Clinic

Citations 78

The role of perioperative systemic therapy in localized pancreatic neuroendocrine tumor.
Yadav, Siddhartha , Keutgen, Xavier M. , Hobday, Timothy J. , Hálfdánarson, Þorvarður R. , Yadav, Siddhartha , Halfdanarson, Thorvardur R , Xie, Hao , Strosberg, Jonathan

Journal of Clinical Oncology | January 29, 2019 | Volume: 37 | Issue: 4_suppl | Pages: 322-322

10.1200/jco.2019.37.4_suppl.322 Get It

322 Background: The role of perioperative systemic therapy (PST) is unclear in the management of localized pancreatic neuroendocrine tumor (pNET). We aim to evaluate the benefit of PST compared to surgical resection alone in localized pNET. Methods: We identified patients with stage I–III pNET who underwent curative-intent surgical resection in National Cancer Database from 2006 to 2014. Patients who underwent PST and surgical resection were matched with patients who received surgery alone by propensity score at 1:1 ratio with nearest neighbor method. Factors predicting the use of PST were identified from logistic regression. Survival was estimated with Kaplan-Meier method and compared with Cox proportional hazards regression. Results: 4919 patients were included in this study with median age of 60 years. 1397 (28%) patients had pNET at the head of pancreas. 2708 (55%) patients had pNET at pancreas body and tail. 334 (6.8%) patients received PST. Factors associated with significant more use of PST compared to surgery alone were age < 65 years, low income, community medical facilities, grade 3/4 tumor, tumor at the head of pancreas, T3-4 tumor and N1 tumor. 310 patients in PST group were matched with 310 patients in surgery alone group, with no significant difference for all covariates after match. For those in PST group, 64 (21%) patients received neoadjuvant systemic therapy, 173 (56%) patients received adjuvant systemic therapy, 7 (2.3%) patients received both, and 66 (21%) patients received PST without clear sequence. In the matched cohort, PST group had significantly shorter overall survival (OS) compared to surgery alone group (median OS 91.1 months versus not reached, p = 0.04). This finding was confirmed by multivariable Cox proportional hazards regression in unmatched cohort with HR 1.5 (95% CI 1.2 – 1.9, p = 0.002). Subgroup analysis in patients with grade 3/4 tumor demonstrated PST group has a trend of shorter OS compared to surgery alone group (median OS 34.1 versus 54.4 months, p = 0.1). Conclusions: PST compared to surgery alone is associated with worse OS in patients with localized pNET. This finding suggests that we may use PST in localized pNET with caution in the absence of solid clinical trial data.
Aspirin and statin use and the risk of gallbladder cancer.
Prasai, Kritika , Mady, Mohamed, Yadav, Siddhartha , Hassan, Mohamed A. , Roberts, Lewis R. , Roberts, Lewis R , Yadav, Siddhartha , Mahipal, Amit

Journal of Clinical Oncology | January 29, 2019 | Volume: 37 | Issue: 4_suppl | Pages: 243-243

10.1200/jco.2019.37.4_suppl.243 Get It

243 Background: The risk factors for gallbladder cancer (GBC) are poorly understood and preventive therapeutic options have not been identified. The use of aspirin (ASA) and/or statin has been associated with reduced risk of several gastrointestinal cancers. In this study, we explore if the use of ASA or statin is associated with a reduced risk of GBC. Methods: We identified patients with GBC diagnosed between the years 2000 and 2016 at Mayo Clinic. We identified matched controls in 2:1 fashion for age, gender and country of residence from patients who underwent cholecystectomy at Mayo Clinic. We collected information on co-morbidities and use of statins or ASA by retrospective chart review. We compared baseline characteristics between cases and controls using Fisher’s exact test for categorical variables and Mann-Whitney U test for continuous variables. We used binomial logistic regression to calculate the odds ratio (OR) and 95% confidence intervals (CI) to estimate the association of ASA or statin use with GBC. The logistic regression model included history of cholelithiasis, diabetes, hypercholesterolemia (HCL), hypertension (HTN), hyperthyroidism, hypothyroidism, primary sclerosing cholangitis (PSC), inflammatory bowel disease (IBD), cirrhosis and statin or ASA use as covariates. Results: 633 cases and 1,266 controls were included in our final analysis. The median age at diagnosis of cases and controls was 67 years. The control group had a significantly (p < 0.05) higher proportion of patients with cholelithiasis, HCL, HTN, hypothyroidism and liver cirrhosis compared to the cases. The case group,contrarily, had a significantly higher proportion of patients with PSC and IBD. In univariate analysis, ASA (OR: 0.41; 95% CI: 0.33-0.52) or statin (OR: 0.48; 95% CI: 0.38-0.60) use was associated with a lower risk of GBC (p < 0.001). However, in multivariate analysis, ASA use was associated with a lower risk of GBC (OR: 0.52; 95% CI: 0.41-0.67, p < 0.001) whereas statin use was not (OR: 0.76; 95% CI: 0.56-1.03, p = 0.08). Conclusions: Our study demonstrates that aspirin use is associated with a reduced risk of GBC, whereas statin use is not. Further studies on GBC are needed to confirm these results and to elucidate mechanisms that explain the risk reduction with aspirin.
Characterization of Comorbidities Limiting the Recruitment of Patients in Early Phase Clinical Trials
Duma, Narjust , Kothadia, Sejal, Azam, Tariq U. , Yadav, Siddhartha , Aguilera, Jesus Vera, Vélez, Miguel González , Hálfdánarson, Þorvarður R. , Molina, Julian R. , Mansfield, Aaron S. , Adjei, Alex A. , Vera Aguilera, Jesus, Hubbard, Joleen M. , Mansfield, Aaron S , Yadav, Siddhartha , Halfdanarson, Thorvardur R , Paludo, Jonas , Go, Ronald S.

The Oncologist | November 9, 2018 | Volume: 24 | Issue: 1 | Pages: 96-102

10.1634/theoncologist.2017-0687 Get It

Abstract Background Early phase clinical trials evaluate the safety and efficacy of new treatments. The exclusion/inclusion criteria in these trials are usually rigorous and may exclude many patients seen in clinical practice. Our objective was to study the comorbidities limiting the participation of patients with breast, colorectal, or lung cancer in clinical trials. Materials and Methods We queried ClinicalTrials.gov on December 31, 2016. We reviewed the eligibility criteria of 1,103 trials. Logistic regression analyses were completed, and exclusion was studied as a binary variable. Results Out of 1,103 trials, 70 trials (6%) excluded patients &gt;75 years of age, and 45% made no reference to age. Eighty-six percent of trials placed restrictions on patients with history of prior malignancies. Regarding central nervous system (CNS) metastasis, 416 trials (38%) excluded all patients with CNS metastasis, and 373 (34%) only allowed asymptomatic CNS metastasis. Regarding chronic viral infections, 347 trials (31%) excluded all patients with human immunodeficiency virus, and 228 trials (21%) excluded all patients with hepatitis B or C infection. On univariate analysis, chemotherapy trials were more likely to exclude patients with CNS metastasis and history of other malignancies than targeted therapy trials. Multivariate analysis demonstrated that industry-sponsored trials had higher odds of excluding patients with compromised liver function. Conclusion Many clinical trials excluded large segments of the population of patients with cancer. Frequent exclusion criteria included patients with CNS metastasis, history of prior malignancies, and chronic viral infections. The criteria for participation in some clinical trials may be overly restrictive and limit enrollment. Implications for Practice The results of this study revealed that most early phase clinic trials contain strict exclusion criteria, potentially excluding the patients who may be more likely to represent the population treated in clinical settings, leaving patients susceptible to unintended harm from inappropriate generalization of trial results. Careful liberalization of the inclusion/exclusion criteria in clinical trials will allow investigators to understand the benefits and drawbacks of the experimental drug for a broader population, and possibly improve recruitment of patients with cancer into clinical trials.
Patterns of palliative care utilization in stage IV non-small cell lung cancer in the National Cancer Database.
Duma, Narjust , Frank, Ryan D. , Yadav, Siddhartha , Molina, Julian R. , Moynihan, Timothy J. , Yadav, Siddhartha , Durani, Urshila , Goyal, Gaurav , Mansfield, Aaron S. , Ailawadhi, Sikander , Go, Ronald S.

Journal of Clinical Oncology | September 5, 2018 | Volume: 36 | Issue: 15_suppl | Pages: 10109-10109

10.1200/jco.2018.36.15_suppl.10109 Get It

Sex differences in tolerability to Anti-PD1 therapy: Are we all equal?
Duma, Narjust , Yadav, Siddhartha , Vera-Aguilera, Jesús, Kottschade, Lisa A. , Adjei, Alex A. , Dronca, Roxana , Yadav, Siddhartha , Paludo, Jonas , Enninga, Elizabeth Ann L. , Dong, Haidong

Journal of Clinical Oncology | September 5, 2018 | Volume: 36 | Issue: 15_suppl | Pages: 9547-9547

10.1200/jco.2018.36.15_suppl.9547 Get It

A Retrospective Study Analyzing the Appropriateness of Initial Treatment of Clostridium difficile in Patients with Active Malignancy
Fisher, Aaron , Khanal, Pradeep, Gniado, Ewa, Khaddour, Leila, Orosey, Molly , Hader, Ismail , Yadav, Siddhartha , Halalau, Alexandra , Yadav, Siddhartha , Halalau, Alexandra

Gastroenterology Research and Practice | May 27, 2018 | Volume: 2018 | Issue: No issue available | Pages: 1-8

10.1155/2018/7192728 Get It

Background. Clostridium difficile infection (CDI) is the leading cause of hospital-associated gastrointestinal illness. Previous studies reported that patients with active malignancy are at high risk for CDIs, and yet they are still classified as nonsevere CDI and initially treated with metronidazole. Our aim is to investigate the need for the escalation of antibiotic therapy in patients with CDI and active cancer treated with oral metronidazole versus oral vancomycin. Methods. This is a retrospective study of adult patients admitted with CDI and any underlying active malignancy at Beaumont Hospital, Royal Oak, Michigan, from January 2008 to December 2014. Inclusion criteria included age > 18 years old, polymerase chain reaction- (PCR-) proven CDI, and active malignancy. Results. 197 patients were included in the final analysis. 44.8% of the metronidazole group required escalation of therapy compared to 15.2% in the vancomycin group (p value = 0.001). 29.8% of the combination group (metronidazole and vancomycin) underwent deescalation of antibiotics, which was significantly higher compared to 2.2% of patients in the vancomycin group (p value < 0.001). Discussion. Our results support the initial use of vancomycin or a combination (metronidazole and vancomycin) versus metronidazole in patients with CDI and active malignancy.
Cardiac Tamponade as the Initial Presentation of Acute Myeloid Leukemia: A Case Report with Review of the Literature
Karmo, Dillon , Hafeez, Adam , Halalau, Alexandra , Yadav, Siddhartha , Yadav, Siddhartha , Halalau, Alexandra

Case Reports in Oncological Medicine | March 26, 2018 | Volume: 2018 | Issue: No issue available | Pages: 1-3

10.1155/2018/8201917 Get It

Acute myeloid leukemia (AML) is a complex disease with a variety of presentations. A large pericardial effusion is rare, occurring in less than 0.5% of all patients with AML prior to treatment. A 34-year-old male presented with dyspnea, malaise, and weight loss. On physical exam, he was noted to be hypoxic, tachypneic, tachycardic, and hypotensive. He had cervical lymphadenopathy and jugular venous distention. His WBC count was 110 bil/L with 33% blasts. Bone marrow biopsy confirmed AML with 60% blasts. Leukemic cells were also seen in the cerebrospinal fluid on lumbar puncture. An echocardiogram revealed a large pericardial effusion causing tamponade. He underwent emergent pericardiocentesis, and malignant cells were present in the pericardial fluid. Induction therapy with standard dose cytarabine and daunorubicin was initiated, and bone marrow biopsy 14 days later showed no residual AML. This case demonstrates the importance of a thorough evaluation of each organ system when caring for a patient with AML.
Impact of preoperativeBRCA1/2testing on surgical decision making in patients with newly diagnosed breast cancer
Yadav, Siddhartha , Jinna, Sruthi , Pereira-Rodrigues, Otavio, Reeves, Ashley , Campian, Sarah, Sufka, Amy, Zakalik, Dana , Yadav, Siddhartha

The Breast Journal | March 2, 2018 | Volume: 24 | Issue: 4 | Pages: 541-548

10.1111/tbj.13007 Get It