Small Cell Lung Cancer Research Turns to Molecular Subtypes and Brain Metastases

Small cell lung cancer (SCLC) has historically lagged behind non-small cell lung cancer in treatment advances, but recent research presented at the 2026 ASCO Annual Meeting suggests the gap may be starting to close on two fronts: brain metastases and molecular subtyping.

Updated analysis of the DeLLphi-304 trial — the study behind tarlatamab's approval — examined the drug's effectiveness against brain metastases specifically, an important question given how frequently SCLC spreads to the brain. Separately, researchers previewed early work suggesting that molecular SCLC subtypes, labeled SCLC-A, SCLC-N, SCLC-P, and SCLC-I, might predict which patients benefit most from lurbinectedin plus atezolizumab maintenance therapy following initial treatment.

If validated, subtype-selected maintenance therapy would mark a shift toward the same biomarker-guided treatment model that has already transformed non-small cell lung cancer care over the past decade, applied for the first time in a systematic way to small cell disease.

SCLC makes up roughly 10-15% of all lung cancer diagnoses but is disproportionately aggressive. See our article library for a plain-language breakdown of how small cell and non-small cell lung cancers differ.