Potential Disparities in Treatment Outcomes of Combination Chemoimmunotherapy in African American females with Extensive-Stage Small Cell Lung Cancer (ED-SCLC): A Case Series Analysis

ED-SCLC is associated with a poor prognosis. Combination chemoimmunotherapy using Etoposide-Platinum (EP) along with Atezolizumab/Durvalumab has emerged as standard of care for these patients with an expected median overall survival (mOS) and median progression free survival (mPFS) reported to be better than EP alone (12.3 months vs.10.3 months, 5.2 months vs 4.3 months respectively). In our comprehensive cancer center, we have observed a trend of low mPFS among African American females with ED-SCLC treated with combination chemoimmunotherapy. We aim to elucidate the baseline demographics and clinical variables of these patients and investigate potential explanations for low mPFS.

We conducted a retrospective review of medical charts of ED-SCLC patients treated with combination chemoimmunotherapy

Three black females with confirmed ED-SCLC diagnosis underwent treatment with combination chemoimmunotherapy. Mean age was 70.6 years.

They received EP along with Atezolizumab for first 4 cycles followed by single agent atezolizumab. The mPFS was 4 months vs. 5.2 months noted in the clinical trial.

This case series highlights a trend of low mPFS observed in black females with ED-SCLC treated with combination chemoimmunotherapy. It is plausible that African American females may harbor certain mutations explaining their poor response to the standard of care treatment. Notably, the inclusion of black patients was limited in the randomized trials of combination chemoimmunotherapy (1/201 patients in IMpower133, 2/268 patients in the CASPIAN trial). Future studies with a larger cohort of black females are warranted to validate the efficacy of combination chemoimmunotherapy in this population.