Case Report: A small cell lung cancer transformed from an <i>EGFR</i>-mutated Adenocarcinoma demonstrated a long-term remission to anti PD-1 antibody.

ABSTRACT: Transformation to small cell lung cancer (SCLC) is a resistance mechanism in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) after EGFR-tyrosine kinase inhibitor (EGFR-TKI) treatment. The efficacy of immune checkpoint inhibitor (ICI) in transformed SCLC remains to be elucidated. The present case report highlights a patient whose tumor underwent transformation to SCLC after developing resistance to an EGFR-TKI treatment. The patient subsequently achieved long-term remission lasting more than 5 years through treatment with an anti-PD-1 antibody nivolumab. Generally, the efficacy of ICI is inferior in EGFR-mutated NSCLC compared to those with EGFR wild-type NSCLC. However, some cases that have transformed to SCLC may be sensitive to ICI

SUBMITTER: Kawanaka Y 

PROVIDER: S-EPMC12457102 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature