Clinical outcomes of ROS1-positive non-small cell lung cancer with limited access to ROS1-tyrosine kinase inhibitors (TKIs): experience from an Indian tertiary referral centre.

Introduction: ROS1 as a driver mutation is observed in approximately 1%-2% of all non-small cell lung cancer (NSCLC). Given its rarity, we share our experience regarding ROS1-positive NSCLC including the access to ROS1 tyrosine kinase inhibitors (TKIs) in a low-middle income country like India. Methods: It is a retrospective analysis of ROS1-positive NSCLC patients registered between January 2015 to December 2021 for demographics, treatment patterns and outcomes i.e., overall survival (OS) and progression free survival (PFS). Results: Baseline characteristics were available for 70 patients of 78 patients positive for ROS1 by fluorescent in situ hybridisation. Median age at presentation was 52 years, 39 (55.7%) were males, most (51, 72.86%) were non-smokers and ten patients (14.3%) had poor Eastern Cooperative Oncology Group (ECOG) performance status (PS) i.e., PS >2 at presentation. A total of 67 patients receiving cancer directed therapy were analysed for survival. The first line (1L) therapies included - ROS1 TKIs in 38, chemotherapy in 20, epidermal growth factor receptor TKI in eight and chemotherapy-bevacizumab in one only. ROS1 TKI was provided to 20 patients as part of an assistance programme. The median OS for patients who received ROS1 TKI was not attained (95% CI 37.85-NA), while it was 8.11 (95% CI 6.31-NA) months for those who did not (HR-0.1673). The median PFS for the 1L ROS1 TKI compared to the no-TKI group was 27.07 (95% CI 24.28-NA) months versus 5.78 (95% CI 3.42-12) months (HR: 0.2047). Poor ECOG PS at presentation was the only independent prognosticator for survival. Conclusion: Using ROS1 TKI improves clinical outcomes in all-comers though statistically not significant. To further improve outcomes, future trials should pay special attention to patients with poor PS and find a way to increase the current limited access to TKI.

Treatment pattern and outcomes in de novo T790M-mutated non-small cell lung cancer.

Introduction: Limited data exists for non-small cell lung cancer (NSCLC) patients harbouring de novo T790M mutation. Methods: NSCLC patients, with de novo T790M, who registered at our institute between 01/03/2015 and 31/12/2019, were considered for retrospective analysis of treatment pattern and clinical outcomes, i.e., progression-free survival (PFS) and overall survival (OS). Results: Of 1,542 epidermal growth factor receptor (EGFR)-mutated patients, 40 (2.59%) had de novo T790M. Most were male (27, 67.5%) and smokers (23, 57.5%). The commonest site of metastasis was the lungs (31, 77.5%), while 7 (17.5%) had central nervous system (CNS) involvement. Additional EGFR gene mutations and anaplastic lymphoma kinase (ALK) positivity were observed in 20 (50.0%) and 4 (10.0%) cases, respectively. The first-line systemic therapy and the number of patients receiving it were as follows: osimertinib by 14 (35.0%), first-generation EGFR tyrosine kinase inhibitors (TKIs) by 10 (25.0%), gefitinib + chemotherapy by 3 (7.5%), chemotherapy by 7 (17.5%) and gefitinib + bevacizumab by 2 (5%). One patient defaulted before starting any treatment. Hence, 39 were considered for survival analysis. The median PFS and OS for the entire cohort were 10.4 (95% CI = 7.6-19.7) months and 24.9 (95% CI = 15.7-NA) months, respectively. The median PFS for patients on osimertinib was 19.8 (95% CI = 11.6-28.0) months versus 8.8 (95% CI = 6.6-10.9) months for those on other systemic therapy. No CNS involvement, use of osimertinib or first-generation EGFR TKI plus chemotherapy or ALK inhibitor in ALK-positive cases prognosticated better PFS. When compared to other systemic therapies, osimertinib improved PFS in patients with or without additional EGFR mutations, although it was statistically significant for the former group only (p = 0.002). Conclusion: The incidence of de novo T790M is low. Osimertinib in frontline therapy provides promising outcomes.

Small cell carcinoma of the oesophagus: experience of an Indian Tertiary Cancer Centre.

Introduction: Small cell carcinoma of the oesophagus (SCCE) is a rare and aggressive tumour with no established standard treatment. Methods: This is a retrospective study of adult patients with histologically proven SCCE registered between February 2011 and March 2020 at Tata Memorial Hospital in Mumbai. Results: There were 56 patients, with 29 (51.8%) having limited-stage disease (LD) and 27 (48.2%) having extensive-stage disease (ED). The median age was 58 (interquartile range = 51-65) years; 57.1% were men; and 40% were smokers. Among LD-SCCE patients, 23 underwent local therapy, i.e., radiation (19, 65.5%) and surgery (4, 13.8%), and 27 received chemotherapy in neoadjuvant (23, 79.3%), concurrent (18, 62.1%) and adjuvant (4, 13.8%) settings. Totally, 19 ED-SCCE patients (70.4%) received chemotherapy. Prophylactic cranial irradiation (PCI) was delivered to 11 (37.9%) and 7 (25.9%) patients with LD-SCCE and ED-SCCE, respectively. Significant grade 3 or more chemotoxicities in patients with LD-SCCE and ED-SCCE included febrile neutropenia in 33.3% and 23.5%, anaemia in 9.5% and 17.6%, and dyselectrolytemia in 14.3% and 11.8%, respectively. The median overall survival (OS) in LD-SCCE and ED-SCCE was 22.9 (95% CI = 1.8-44.1) months and 11.8 (95% CI = 7.3-16.4) months, respectively. Age <60 years (p = 0.004) and tumour epicentre in the lower third oesophagus (p = 0.002) were independent good prognostic factors for OS in LD-SCCE and ED-SCCE patients, respectively. The incidence of brain metastasis was low, at both presentation (1/27, 3.7%) and relapse (5/56, 8.9%). Conclusion: Although the survival of LD-SCCE is better than ED-SCCE, it is still under 2 years. Brain metastases are uncommon and the role of PCI is uncertain.

Adolescent-adult nonmetastatic Ewing sarcoma-Experience from a large developing country.

BACKGROUND: Outcome and toxicity data in adolescent-adult Ewing sarcoma (AA-ES) patients are sparse and merits exploration. METHODS: Histopathologically confirmed, nonmetastatic AA-ES patients, who received standard institutional combination chemotherapy regimen (Ewing's family of tumors-2001 [EFT-2001]) comprising of ifosfamide plus etoposide and vincristine, doxorubicin plus cyclophosphamide, lasting a total of 12 months between 2013 and 2018, were analyzed for treatment-related toxicities, event-free survival (EFS), and overall survival (OS). RESULTS: There were 235 patients (primary safety cohort [PSC]) with median age of 23 (15-61) years; 159 (67.7%) were males, 155 (65.9%) had skeletal primary and 114 (48.5%) had extremity tumors. One hundred ninety-six (83.4%) were treatment naïve (primary efficacy cohort [PEC]) and of these 119 (60.7%) had surgery. In PEC, at a median follow-up of 36.4 (interquartile range [IQR] 20-55) months, estimated 3-year EFS and OS were 67.3% (95% CI 60.3-75.1%) and 91.1% (95% CI 86.7-95.7%), respectively. Of these, 158 (80.6%) complying with intended treatment, at a median follow-up of 39 (IQR 26-57) months had an estimated 3-year EFS of 68.2% (95% CI 60.3-76.1%). In multivariable analysis, good prognostic factors included longer symptom(s) duration (HR 0.93, 95% CI 0.86-0.994), ≥99% necrosis (HR 0.30, 95% CI 0.11-0.77), and treatment completion (HR 0.32, 95% CI 0.14-0.74). Among PSC, grade 3-4 toxicities were febrile neutropenia (119, 50.6%), anemia (130, 55.3%), peripheral neuropathy (37, 15.7%), with three (1.3%) chemo-toxic deaths. CONCLUSIONS: The outcomes of AA nonmetastatic ES patients treated with EFT-2001 regimen were comparable to those reported by others, with acceptable toxicity. This regimen can be considered a standard of care in AA-ES.