Anant Ramaswamy

Synthesis and characterization of a crystalline vanadium silicate with MEL structure

Synthesis of a novel crystalline vanadium silicate having the MEL structure (silicalite-2) is reported. Tetraethyl orthosilicate and vanadyl sulfate were the raw materials and tetrabutylammonium hydroxide was the additive. The influence of various synthesis parameters such as the SiV molar ratio, concentration of the organic base, and dilution levels on the crystallization of vanadium silicate has been investigated. The kinetics of crystallization has been followed using X-ray powder diffraction, SEM, framework i.r., and e.s.r. spectroscopic techniques. Under optimum conditions of synthesis, vanadium is incorporated as V4+ in a progressive manner in the MEL framework during the crystallization process. After calcination in air at 773 K, most of the vanadium (as V5+) is still intact within the silicalite structure.

Drug-sensitive FGFR3 mutations in lung adenocarcinoma

Background Lung cancer is the leading cause of cancer-related deaths across the world. In this study, we present therapeutically relevant genetic alterations in lung adenocarcinoma of Indian origin. Materials and methods Forty-five primary lung adenocarcinoma tumors were sequenced for 676 amplicons using RainDance cancer panel at an average coverage of 1500 × (reads per million mapped reads). To validate the findings, 49 mutations across 23 genes were genotyped in an additional set of 363 primary lung adenocarcinoma tumors using mass spectrometry. NIH/3T3 cells over expressing mutant and wild-type FGFR3 constructs were characterized for anchorage independent growth, constitutive activation, tumor formation and sensitivity to FGFR inhibitors using in vitro and xenograft mouse models. Results We present the first spectrum of actionable alterations in lung adenocarcinoma tumors of Indian origin, and shows that mutations of FGFR3 are present in 20 of 363 (5.5%) patients. These FGFR3 mutations are constitutively active and oncogenic when ectopically expressed in NIH/3T3 cells and using a xenograft model in NOD/SCID mice. Inhibition of FGFR3 kinase activity inhibits transformation of NIH/3T3 overexpressing FGFR3 constructs and growth of tumors driven by FGFR3 in the xenograft models. The reduction in tumor size in the mouse is paralleled by a reduction in the amounts of phospho-ERK, validating the in vitro findings. Interestingly, the FGFR3 mutations are significantly higher in a proportion of younger patients and show a trend toward better overall survival, compared with patients lacking actionable alterations or those harboring KRAS mutations. Conclusion We present the first actionable mutation spectrum in Indian lung cancer genome. These findings implicate FGFR3 as a novel therapeutic in lung adenocarcinoma.

ALK Positive Lung Cancer: Clinical Profile, Practice and Outcomes in a Developing Country

Objectives To evaluate the performance and treatment profile of advanced EML4—ALK positive Non-small cell lung cancer (NSCLC) patients in a developing country with potentially restricted access to Crizotinib. Materials and Methods A retrospective analysis of advanced ALK positive NSCLC patients who were treated from June 2012 to September 2015 was conducted. The primary goal was to evaluate outcomes of advanced ALK positive NSCLC in our practice and examine the logistic constraints in procuring Crizotinib. Results 94 patients were available for analysis. 21 (22.3%) patients were started on Crizotinib upfront, 60 (63.8%) on chemotherapy, 10 (10.6%) on Tyrosine kinase inhibitors (in view of poor PS) and 3 (3.2%) patients were offered best supportive care. Reasons for not starting Crizotinib upfront included symptomatic patients needing early initiation of therapy (23.3%), ALK not tested upfront (23.3%) and financial constraints (21.9%). 69 patients (73.4%) received Crizotinib at some stage during treatment. Dose interruptions (> 1 week) with Crizotinib were seen in 20 patients (29%), with drug toxicity being the commonest reason (85%). Median Progression free survival (PFS) on first line therapy for the entire cohort was 10 months, with a significant difference between patients receiving Crizotinib and those who did not ever receive Crizotinib (10 months vs. 2 months, p = 0.028). Median Overall Survival (OS) was not reached for the entire cohort, with 1 year survival being 81.2%. Patients with an ECOG Performance Status (PS) of >2 had a significantly reduced PFS compared to patients with PS < = 2 (1.5 months vs. 11 months, p< 0.001). 47 patients with financial constraints (68.1%) received Crizotinib completely free via various extramural support schemes. Conclusion A majority of our ALK positive NSCLC patients were exposed to Crizotinib through the help of various support mechanisms and these patients had similar outcomes to that reported from previously published literature.

Dihydro pyrimidine dehydrogenase deficiency in patients treated with capecitabine based regimens: a tertiary care centre experience

BACKGROUND Dihydropyrimidine dehydrogenase (DPD) enzyme is the rate limiting step in the metabolism of capecitabine, and its deficiency leads to severe toxicities and rarely, death. METHODS A total of 506 patients were treated in the GI Medical Oncology unit of our institution with capecitabine containing regimens with a dose range of 1,250 to 2,000 mg/m(2)/day during the period from June 2013 to June 2015. Patients with grade (Gr) 3/4 toxicities requiring in-patient care (life threatening complications) were planned for DPD activity testing by peripheral blood PCR sequencing. RESULTS Thirty-one patients developed Gr 3/4 toxicities during cycle 1 of capecitabine. This included mucositis in 24 (77%), diarrhea in 29 (94%), hand-foot syndrome (HFS) in 13 (42%) and myelosuppression in 5 (16%) patients. Twenty-two (81.4%) were found to be DPD deficient with 6 patients negative for DPD mutation. Three patients did not undergo the DPD analysis as advised. More than one mutation was seen in 11 patients. The relative frequencies of the mutations were IVS14+1G→A in 39%, with 13% having homozygosity, 85 T→C in 36%, 1627 A→G in 32%, 496 A→G in 18% and 2194 G→A in 18%, respectively. After dose reduction in cycle 2 in 17 patients of the DPD mutation positive cohort, statistically significant reduction in the toxicities was seen. CONCLUSIONS Dose reduction in DPD deficient patients, reduces risk of life threatening complications significantly but not completely. Upfront screening for DPD deficiency in Indian patients should be evaluated further in view of potentially high homozygous DPD mutation prevalence.

Neoadjuvant chemotherapy in geriatric head and neck cancers: Neoadjuvant chemotherapy in geriatric head and neck cancers

The purpose of this study was to present our findings on the treatment completion rates and outcomes in geriatric patients with head and neck cancer treated with neoadjuvant chemotherapy followed by definitive therapy.

Phase III study of gefitinib or pemetrexed with carboplatin in EGFR-mutated advanced lung adenocarcinoma

Objective Oral tyrosine kinase inhibitor has been shown to prolong progression-free survival (PFS) in epidermal growthfactor receptor (EGFR) mutation positive adenocarcinoma; however, the comparator arm has not included the current standard adenocarcinoma regimen (pemetrexed carboplatin induction followed by maintenance pemetrexed) and patients from Indian subcontinent. Hence, this study was carried out in Indian patients to compare gefitinib with the above-mentioned chemotherapy regimen. Methods This was an open-labelled, randomised, parallel group study comparing gefitinib (250 mg orally daily) with pemetrexed (500 mg/m2) and carboplatin (area under the curve 5) doublet intravenous induction chemotherapy regimen followed by maintenance pemetrexed (500 mg/m2) in patients with EGFR-activating mutation-positive stage IIIB or stage IV adenocarcinoma lung in the first-line setting. The primary endpoint for the study was PFS. 260 patients were required to demonstrate a 50% improvement in PFS of gefitinib over chemotherapy, with 80% power and 5% type 1 error. With an expected 5% dropout rate, the sample size was 290 patients. Results The median PFS in gefitinib arm was 8.4 months (95% CI 6.3 to 10.5 months) compared with 5.6 months (95% CI 4.2 to 7.0 months) in pemetrexed–carboplatin arm (HR: 95% CI 0.513 to 0.851; p −0.001). The impact of gefitinib on PFS was seen across all subgroups.There was no statistically significant difference in overall survival between the two arms. Haematologicalgrade3–4toxicities likeanaemia,neutropaenia and thrombocytopaenia were common in the pemetrexed–carboplatin arm while grade3–4 acneiform rash and diarrhoeawere common in the gefitinib arm. Conclusion The study confirms the superiority of gefitinib in prolonging PFS against the most active chemotherapy regimen of pemetrexed–carboplatin followed by maintenance pemetrexed in EGFR-mutated lung adenocarcinoma. The median PFS in Indian patients in gefitinib arm is similar to that reported in east Asians and Caucasians.

Weekly paclitaxel as metronomic palliative chemotherapy in small cell lung cancer

Background: Topotecan is the standard second line agent used in relapsed small cell lung cancer (SCLC). However, the erratic availability and the cost of the drug has been a prohibitive factor for its use in second-line setting in India. Paclitaxel has shown antitumor activity in heavily pretreated patients with SCLC. Hence, this audit was performed to study the efficacy of weekly paclitaxel as a form of metronomic therapy in the second-line setting in SCLC. Materials and Methods: Fifty-seven patients of relapsed SCLC who presented to the thoracic medical oncology unit of Tata Memorial Centre, Mumbai between January 2011 and December 2015 were selected for this analysis. Weekly paclitaxel at a dose of 80 mg/m 2 was administered until progression or development of intolerable side effects or patient refusal. Data regarding baseline demographics, previous treatment history, response rate, progression-free survival, overall survival (OS), and toxicity to weekly paclitaxel was extracted from a prospectively maintained database in the thoracic medical oncology unit and was analyzed using SPSS version 16 (IBM, New York, USA). Kaplan-Meier survival analysis was performed. Results: Median age of the cohort was 58 years (40-77 years). Etoposide with carboplatin was the regimen used in 40 patients (70.2%) whereas the remaining 17 patients received etoposide with cisplatin (29.8%). Eastern Cooperative Oncology Group performance status at relapse was 1 in 3 (5.3%), 2 in 49 (86.0%), and 3 in 5 (8.7%) patients. The response rate and clinical benefit rate were 9.1% (5 patients) and 52.7% (29 patients), respectively. Grade 3-4 toxicities were seen in 10.5% (6 patients). The median PFS was 145 days (95% confidence interval [CI]: 116.6-173.5 days) whereas the median OS was 168 days (95% CI: 112.5-223.5 days). Conclusion: Weekly paclitaxel as a second line agent in relapsed small cell cancer of the lung is a feasible and well-tolerated agent.

Pazopanib in metastatic multiply treated progressive gastrointestinal stromal tumors: feasible and efficacious

BACKGROUND A median progression free survival (PFS) of 18-20 months and median overall survival (OS) of 51-57 months can be achieved with the use of imatinib, in metastatic or advanced gastrointestinal stromal tumor (GIST). Sunitinib and regorafenib are approved options for patients progressing on imatinib, but with markedly decreased survival. pazopanib is a broad spectrum TKI targeting KIT, PDGFR and VEGFR receptors and has shown promising activity in phase 2 trials in GIST. METHODS All patients who received pazopanib for GIST between March 2014 and September 2015 in our institution were reviewed. Patients were assessed for response with CT or PET CT scans. Patients continued pazopanib until progression or unacceptable toxicity. Survival was evaluated by Kaplan Meier product method. RESULTS A total of 11 consecutive patients were included in our study. Median duration of follow up was seven months. The median lines of prior therapy was 2 [1-5]. Partial response (PR) was observed in seven patients and two had stable disease (SD). Two patients died within one month of start of pazopanib. Five of ten patients had progressed during the study with eight patients still alive. The median PFS was 11.9 months and the median OS was not reached. Common adverse events seen were hand-foot-syndrome (HFS) in four patients, anemia in four patients and fatigue in three patients. Grade 3/4 adverse events were uncommon. Three patients required dose modification of pazopanib. CONCLUSIONS Pazopanib is a reasonably efficacious well tolerated TKI and can be explored as a treatment option in advanced GIST that has progressed on imatinib.

Emerging role of multimodality treatment in gall bladder cancer: Outcomes following 510 consecutive resections in a tertiary referral center

Gall bladder cancer (GBC) is a disease with high incidence in India. We analyzed the outcomes of patients with suspected GBC who underwent surgical exploration.

Treatment of advanced Gall bladder cancer in the real world—can continuation chemotherapy improve outcomes?

BACKGROUND Gemcitabine-Platinum doublet chemotherapy is the standard of care in patients with locally advanced inoperable and metastatic (LA/M) Gall bladder cancers (GBC). METHODS Consecutive patients with LA/M GBC treated with Gemcitabine-Cisplatin (GC) or Gemcitabine-Oxaliplatin (GO) as first line palliative chemotherapy from January 2013 to June 2015 were retrospectively analysed. Patients who were able to continue chemotherapy beyond 6-8 cycles were separately compared to those who were potential candidates for this approach, but chose not to continue chemotherapy. RESULTS A total of 396 patients received first line palliative chemotherapy during the period of analysis, 276 patients (69.6%) were unable to complete 6-8 cycles of chemotherapy, while 120 patients (30.4%) were potential candidates for continuing chemotherapy. Seventy patients (n=120; 58.3%) received a median of 4 cycles of continuation chemotherapy. Median overall survival (OS) for the entire cohort was 7.65 months [95% confidence interval (CI), -7.14 to 8.16], while median event free survival (EFS) was 4.53 months (95% CI, -4.23 to 4.83). Patients receiving continuation chemotherapy had a statistically improved median OS compared to all other patient cohorts, 14.88 months (95% CI, -12.48 to 17.27; P=0.005 on multivariate analysis). Burden/number of sites of metastases, receiving of continuation chemotherapy, fit and able to receive second line chemotherapy (CT2) were identified on multivariate analysis as prognostic factors for OS. CONCLUSIONS OS in our study appeared lower than published literature, but a group of patients were identified whose survival could be prolonged by continuing chemotherapy. Easily available factors can predict prognosis of GBC undergoing first line palliative chemotherapy.