168P Validation of lung specific and lung molecular graded prognostic assessment score in metastatic NSCLC with brain metastases from India

To validate the prognostic value of Lung Specific Graded Prognostic Assessment (DS-GPA) and Lung Molecular GPA (Lung molGPA) in non-small cell lung cancer (NSCLC) patients with brain metastasis (BM) from India. A retrospective analysis of 501 patients treated for BM between January 2020 and November 2022 was performed at our Tertiary Cancer Centre. The prognostic scores of DS-GPA and mol-GPA were calculated and intergroup differences were compared by log-rank test. Overall survival (OS) was calculated from the date of BM diagnosis till death or last known follow-up. Survival curves were estimated by the Kaplan-Meier analysis. A P-value of <0.05 was considered statistically significant. The median follow-up for surviving patients was 21.5 months (3.8 – 50.4). The median age was 53 years (range, 23-80), the majority being male (60%). Adenocarcinoma histology constituted (88%) and squamous carcinoma (6%). EGFR mutation was seen in 50% of patients and ALK rearrangement in 20%. Brain radiotherapy (RT) was offered to 93% of patients; the rest received observation or optimal supportive care. Whole brain RT (WBRT) was delivered to 76% and stereotactic radiosurgery to 17%. Systemic therapy was received by 93% (chemotherapy-39%, TKI - 37%, or a combination - 24%). The patient's distribution in various scoring groups of DS-GPA and mol-GPA and their overall survival are given in the table. The median overall survival was 15.6 months (0.1 - 74.0). The OS was significantly better for those who received 3rd-generation EGFR TKIs as compared to 1st or 2nd-generation, 24.5 vs 14.3 months (p=0.01), and similarly for ALK-positive patients, 26.3 vs 40.7 months (p=0.015). Table: 168PSurvival according to DS-GPA and mol-GPALung-specific GPALung molGPAGroupsNumber (%)Median survival, monthsNumber (%)Median survival, months0-1171 (34.1)7.781 (16.2)3.41.5-2236 (47.1)18233 (46.5)10.12.5-373 (14.6)28.7156 (33.1)28.73.5-421 (4.2)Not reached31 (6.2)39.3Overall50115.6 (p=0.000)50115.6 Open table in a new tab Our study has validated the lung specific-GPA and lung molGPA in NSCLC patients with brain metastases from India and it therefore should be considered to deliver individualized treatment for brain metastases.