Survival outcomes after whole brain radiotherapy for brain metastases in older adults with newly diagnosed metastatic small cell carcinoma: A national cancer database (NCDB) analysis.

Abstract

BACKGROUND\nSmall cell lung cancer (SCLC) is an aggressive malignancy with a tendency to affect older adults and also metastasize to the brain. Older adults tolerate whole brain radiotherapy (WBRT) poorly with marginal survival benefit. We utilized the national cancer database (NCDB) to evaluate the survival outcomes following WBRT in older adults with SCLC and brain metastases.\n\n\nMETHODS\nWe identified 1615 patients ≥75\u202fyears old diagnosed with SCLC and brain metastases. Patients were categorized by type of therapy: chemotherapy + WBRT (n\u202f=\u202f576), chemotherapy alone (n\u202f=\u202f238), WBRT alone (n\u202f=\u202f360) and no chemotherapy or WBRT (n\u202f=\u202f441). Clinical and demographic characteristics were reported for each treatment cohort with a subsequent multivariable regression analysis for survival.\n\n\nRESULTS\nMedian patient age was 79\u202fyears. WBRT median dose was 30\u202fGy. At time of analysis, 1530 of the cohort had died, yielding a median OS of 2.9\u202fmonths and 6\u202fmonth survival of 31% for patients that received chemotherapy. For patients treated without chemotherapy, median OS with WBRT was 1.9\u202fmonths compared to 1.2\u202fmonths without (p\u202f<\u202f.0001). For patients receiving chemotherapy with, and without WBRT, median OS was 5.6\u202fmonths and 6.4\u202fmonths, respectively (p\u202f=\u202f.43). Multivariable cox regression revealed age\u202f>\u202f80, extracranial disease, male sex, and rural location as predictors of increased risk of death.\n\n\nCONCLUSION\nIn older adult patients with SCLC brain metastasis, WBRT was associated with a modest increase in survival in patients not fit for chemotherapy, and there was no association with increased survival over chemotherapy alone.