Fecha de publicación: -- Fuente: PubMed "nature biotechnology" Lung Cancer. 2026 Nov 7;222:109685. doi: 10.1016/j.lungcan.2026.109685. Online ahead of print.ABSTRACTINTRODUCTION: Tarlatamab has demonstrated activity in relapsed small cell lung cancer (SCLC). However, lesion-level response heterogeneity and organ-specific patterns of progression during tarlatamab therapy remain poorly characterized in clinical practice.MATERIALS AND METHODS: We retrospectively evaluated patients with relapsed SCLC treated with tarlatamab between June 2021 and March 2026. Overall response at the first radiological evaluation and best overall response were assessed according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Lesion-level response patterns at the first radiological assessment were categorized as responsive, mixed response, stable, or progressive. Progression sites, intracranial lesion changes, and progression-free survival (PFS) were analyzed. Site-specific findings were summarized at the first evaluation and at overall progressive disease (PD).RESULTS: Twenty-nine patients were included. Mixed response was observed in 11 (37.9%) patients and across the RECIST response categories at the first radiological evaluation. The median PFS was 3.2 months and was longest in the responsive group, intermediate in the mixed-response group, and shortest in the progressive group. Among 15 patients evaluable for intracranial response, seven experienced at least 30% intracranial tumor shrinkage at the first assessment, and four subsequently developed intracranial progression. Among 20 patients with disease progression, 12 had progression at three or more sites. Site-specific assessments showed that decreased or stable disease could coexist with overall PD.CONCLUSION: Tarlatamab showed heterogeneous response and progression patterns in relapsed SCLC, including frequent mixed response and intracranial progression. Lesion-level assessment may provide a more comprehensive characterization of disease behavior during tarlatamab therapy.PMID:43003045 | DOI:10.1016/j.lungcan.2026.109685