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Shruti Kate,1 Anuradha Chougule,2 Amit Joshi,1 Vanita Noronha,1 Vijay Patil,1 Rohit Dusane,3 Leena Solanki,1 Priyanka Tiwrekar,2 Vaishakhi Trivedi,1 Kumar Prabhash1 1Department of Medical Oncology, Tata Memorial Hospital, Mumbai, Maharashtra, India; 2Department of Molecular Pathology, Tata Memorial Hospital, Mumbai, Maharashtra, India; 3Department of Biostatistics, Clinical Research Secretariat, Tata Memorial Hospital, Mumbai, Maharashtra, India Background: The significance of uncommon EGFR mutations in newly diagnosed advanced non-small-cell lung cancer (NSCLC) patients is incompletely known. We aimed to analyze the demographic profile, outcome, and treatment attributes of these patients.Patients and methods: We retrospectively surveyed 5,738 advanced NSCLC patients who underwent EGFR testing in our center from 2013 to 2017 by in-house primer probes on real time PCR platform. Descriptive data were accumulated from electronic medical records. Survival plot was calculated using Kaplan–Meier method and compared between groups using log-rank test.Results: Out of 1,260 EGFR mutation-positive patients, 83 (6.58%) had uncommon mutations in isolation or in various combinations. Uncommon mutations were more frequent in men, never-smokers, and adenocarcinomas. Overall, exon 18 G719X, exon 20 insertion, exon 20 T790M, exon 20 S768I, and exon 21 (L858R/L861Q) were present in 9.6%, 19.3%, 12%, 3.6%, and 3.6% patients, respectively. Dual mutation positivity was found in 50.6% patients. On classifying patients as per tyrosine kinase inhibitor (TKI) sensitivity, it was found that majority of the patients had a combination TKI sensitive and insensitive mutations. The median duration of follow-up was 13 months. Five patients were lost to follow-up. Median progression-free survival on first line therapy was 6.7 months (95% CI: 4.8–8.5). Median overall survival (OS) of patients who received TKI during the course of their disease was 20.2 months (95% CI: 11.4–28.9). Median overall survival (mOS) of the entire cohort was 15.8 months (95% CI: 10.1–21.5). Among all uncommon mutations, patients with dual mutations did better, with an mOS time of 22.6 months (95% CI: 8.2–37.0, P=0.005). It was observed that TKI sensitive/TKI insensitive dual mutations had a superior OS of 28.2 months (95% CI: 15.2–41.2, P=0.039) as compared to TKI sensitive and TKI insensitive EGFR mutations.Conclusion: Uncommon EGFR mutations constitute a heterogeneous group, hence, it is imperative to understand each subgroup more to define optimal treatment. Keywords: uncommon EGFR mutations, advanced NSCLC, tyrosine kinase inhibitors, complex EGFR mutations, dual EGFR mutations

Vidya H Veldore,1,* Anuradha Choughule,2,* Tejaswi Routhu,1 Nitin Mandloi,1 Vanita Noronha,2 Amit Joshi,2 Amit Dutt,3 Ravi Gupta,1 Ramprasad Vedam,1 Kumar Prabhash2 1MedGenome Labs Private Ltd,, Bangalore, India; 2Tata Memorial Centre, Parel, Mumbai, India; 3The Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Center, Kharghar, Navi Mumbai, Maharashtra, India *These authors contributed equally to this work Abstract: Plasma cell-free tumor DNA, or circulating tumor DNA (ctDNA), from liquid biopsy is a potential source of tumor genetic material, in the absence of tissue biopsy, for EGFR testing. Our validation study reiterates the clinical utility of ctDNA next generation sequencing (NGS) for EGFR mutation testing in non-small cell lung cancer (NSCLC). A total of 163 NSCLC cases were included in the validation, of which 132 patients had paired tissue biopsy and ctDNA. We chose to validate ctDNA using deep sequencing with custom designed bioinformatics methods that could detect somatic mutations at allele frequencies as low as 0.01%. Benchmarking allele specific real time PCR as one of the standard methods for tissue-based EGFR mutation testing, the ctDNA NGS test was validated on all the plasma derived cell-free DNA samples. We observed a high concordance (96.96%) between tissue biopsy and ctDNA for oncogenic driver mutations in Exon 19 and Exon 21 of the EGFR gene. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the assay were 91.1%, 100% 100%, 95.6%, and 97%, respectively. A false negative rate of 3% was observed. A subset of mutations was also verified on droplet digital PCR. Sixteen percent EGFR mutation positivity was observed in patients where only liquid biopsy was available, thus creating options for targeted therapy. This is the first and largest study from India, demonstrating successful validation of circulating cell-free DNA as a clinically useful material for molecular testing in NSCLC. Keywords: liquid biopsy, NSCLC, EGFR, ctDNA, NGS

Vanita Noronha,1,* Anuradha Choughule,2,* Vijay M Patil,1,* Amit Joshi,1 Rajiv Kumar,3 Deepa Susan Joy Philip,1 Shripad Banavali,2 Amit Dutt,4 Kumar Prabhash2 1Department of Medical Oncology, 2Department of Medical Oncology-Molecular Laboratory, 3Department of Pathology, Tata Memorial Hospital, 4Dutt Lab, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Mumbai, India *These authors contributed equally to this work Background: There are limited data available on the treatment and outcome of epidermal growth factor receptor (EGFR) exon 20-mutated lung cancer patients. Hence, we planned an analysis of the demographic details, clinical profile and survival of lung cancer patients with exon 20 mutations. We compared our results to patients with EGFR tyrosine kinase inhibitor (TKI)-sensitizing activating and EGFR/anaplastic lymphoma kinase (ALK)-negative mutations. Methods: This was a retrospective analysis of lung cancer patients who were treated at our center between January 2010 and August 2014. We reviewed the results of EGFR mutation testing by real-time polymerase chain reaction and Sanger sequencing. We also reviewed the data relating to baseline demographics, clinical profile, patient treatment and outcome measures in terms of response and overall survival (OS). Results: A total of 580 patients fulfilled the selection criteria. In all, 227 (39.1%) patients had EGFR TKI-sensitizing activating mutations, 20 (3.4%) patients had exon 20 insertion mutations and 333 patients were EGFR/ALK mutation negative (57.5%). The median OS was 5 months (95% confidence interval [CI] 0.17–9.8 months) in exon 20 insertion mutations, 16.1 months (95% CI 12.8–19.5 months) in EGFR TKI-sensitizing activating mutations and 10 months (95% CI 7.9–12.1 months) in EGFR/ALK mutation-negative patients. The median OS was significantly better for the EGFR TKI-sensitizing activating mutation group (P=0.000, log-rank test) and for the EGFR/ALK-negative group (P=0.037, log-rank test) compared to the exon 20-mutated group. Conclusion: Exon 20 mutation results in a poorer OS prognosis compared to EGFR- and ALK-negative patients and patients harboring EGFR TKI-sensitizing activating mutations. The incidence of de novo exon 20 insertions was 3.4%. Different types of exon mutations seem to have different outcomes. Keywords: exon 20, lung cancer, EGFR mutation, TKI resistance, insertions

Amit Joshi,1 Saurabh Zanwar,1 Vanita Noronha,1 Vijay M Patil,1 Anuradha Chougule,2 Rajiv Kumar,3 Amit Janu,4 Abhishek Mahajan,4 Akhil Kapoor,1 Kumar Prabhash1 1Department of Medical Oncology, Tata Memorial Hospital, 2Molecular Laboratory, Department of Medical Oncology, 3Department of Pathology, 4Department of Radiology, Tata Memorial Hospital, Mumbai, Maharashtra, India Background: EGFR tyrosine kinase inhibitors (TKIs) have greatly improved the outcomes of EGFR mutation-positive adenocarcinomas of the lung. In contrast, the significance of EGFR mutation in metastatic squamous cell carcinoma (SCC) of the lung has been debated.Methods: All patients with metastatic SCC who underwent EGFR mutation testing at our center from 2010 to 2015 were included for analysis. EGFR kinase domain mutations were tested using Taqman-based real-time polymerase chain reaction (PCR). Response assessment was done using Response Evaluation Criteria In Solid Tumors (RECIST) 1.1. Kaplan–Meier method was used for calculating progression-free survival (PFS) and overall survival (OS).Results: EGFR mutation was detected in 29 out of 639 patients with SCC. Furthermore, 19 out of the 29 patients received TKIs at some point during their treatment. TKI therapy led to a partial response in 5 out of 19 patients and stable disease in 4 out of 19 patients. The median PFS of patients treated with TKIs was 5.0 months. The median OS of the whole EGFR-positive SCC cohort was 6.6 months. On univariate analysis, patients having received TKI therapy was the only factor associated with a significantly better OS of 13.48 months versus 2.58 months (P=0.000). On multivariate analysis, patients receiving TKI therapy, Eastern Cooperative Oncology Group–Performance Scale (ECOG-PS) score

Background: There is increasing concern regarding efficacy of organ preservation protocol in laryngeal and hypopharyngeal cancers. Method: This study retrospectively assessed disease-related and functional outcomes of 191 patients with non-metastatic laryngeal or hypopharyngeal squamous cell carcinoma treated with curative intent (radiotherapy with or without chemotherapy). Results: Seventy-six patients (39.8 per cent) had a primary cancer in the larynx, and 115 patients (60.2 per cent) had a primary cancer in the hypopharynx. The median follow up was 39 months. The 3-year time to progression, overall survival, local control and laryngectomy free survival was 56.2 per cent, 76.3 per cent, 73.2 per cent and 67.2 per cent, respectively. At the time of analysis, 83 patients (43.5 per cent) were alive and disease free at their last follow up and did not require tube feeding or tracheostomy. The laryngo-oesophageal dysfunction-free survival was 61 per cent at 3 years. Conclusion: Organ conservation protocols remain the standard of treatment in appropriately selected patients with laryngeal and hypopharyngeal cancers. [ABSTRACT FROM AUTHOR]

Vikram Gota,1 Krunal Kavathiya,1 Kartik Doshi,1 Murari Gurjar,1 Solai E Damodaran,1 Vanita Noronha,2 Amit Joshi,2 Kumar Prabhash2 1Department of Clinical Pharmacology, Advanced Centre for Treatment Research and Education in Cancer, 2Department of Medical Oncology, Tata Memorial Hospital, Mumbai, India Background: Pemetrexed-platinum doublet therapy is a standard treatment for stage IIIb/IV nonsquamous non small cell lung cancer (NSCLC). While the regimen is associated with several grade ≥3 toxicities, hyponatremia is not a commonly reported adverse effect. Here we report an unusually high incidence of grade ≥3 hyponatremia in Indian patients receiving pemetrexed-platinum doublet, and the pharmacological basis for this phenomenon. Methods: Forty-six patients with advanced NSCLC were enrolled for a bioequivalence study of two pemetrexed formulations. All patients received the pemetrexed-platinum doublet for six cycles followed by single-agent pemetrexed maintenance until progression. Pharmacokinetic blood samples were collected at predefined time points during the first cycle and the concentration-time profile of pemetrexed was investigated by noncompartmental analysis. Hyponatremic episodes were investigated with serum electrolytes, serum osmolality, urinary sodium, and urine osmolality. Results: Sixteen of 46 patients (35%) had at least one episode of grade ≥3 hyponatremia. Twenty-four episodes of grade ≥3 hyponatremia were observed in 200 cycles of doublet chemotherapy. Plasma exposure to pemetrexed was significantly higher in patients with high-grade hyponatremia than in those with low-grade or no hyponatremia (P=0.063 and P=0.001, respectively). Pemetrexed clearance in high-grade hyponatremia was quite low compared with normal and low-grade hyponatremia (P=0.001 and P=0.055, respectively). Median pemetrexed exposure in this cohort was much higher than that reported in the literature from Western studies. Conclusion: Higher exposure to pemetrexed is associated with grade ≥3 hyponatremia. The pharmacogenetic basis for higher exposure to pemetrexed in Indian patients needs further investigation. Keywords: non small cell lung carcinoma, platinum compounds, pharmacokinetics, pharmacogenetics