Distinct Clinicogenomic Features and Immunotherapy Associations in Pulmonary Sarcomatoid Carcinoma: A Multicenter Retrospective Study
Lingzhi Hong, Alessandro Di Federico, Bolun Liu, Alissa J. Cooper, Joao V. Alessi, Phoebe Clark, Waree Rinsurongkawong, Chingyi Young, Hui Li, Kang Qin, Muhammad Aminu, Valentina Santo, Yasir Y. Elamin, Boris Sepesi, Jeff Lewis, Don L. Gibbons, Ara A. Vaporciyan, J. Jack Lee, Xiuning Le, Jia Wu, Sinchita Roy‐Chowdhuri, Mark J. Routbort, P. Andrew Futreal, John V. Heymach, Mark M. Awad, Adam J. Schoenfeld, Jianjun Zhang, Biagio Ricciuti, Lei Deng, Natalie I. Vokes
Abstract
INTRODUCTION: Pulmonary sarcomatoid carcinoma (PSC) is a rare NSCLC subtype with poor prognosis. Outcomes to immune checkpoint inhibitors (ICIs) and genomic features in PSC remain underexplored compared with other NSCLC subtypes. METHODS: Patients from three institutions and the National Cancer Database (NCDB) with metastatic NSCLC treated with ICI alone or with chemotherapy were identified. Clinicogenomics and treatment outcomes were compared across PSC, lung adenocarcinoma (LUAD), and lung squamous cell carcinoma (LUSC). RESULTS: We analyzed 4841 patients including 165 PSC cases treated with ICI-based therapy from three institutions and 201 PSC from NCDB. In MDACC, 65 (4.3%) were PSC, 1138 (75.1%) LUAD, and 312 (20.6%) LUSC. Patients with PSC were older and more likely to present with metastatic disease. In both the MDACC and NCDB cohorts, ICIs resulted in better outcomes for patients with PSC compared with chemotherapy. In these patients, there was no difference in outcome between ICI-monotherapy and ICI-chemotherapy. Across the three institutional cohorts, 37% to 43% of patients with PSC who received ICIs were responders, compared with 26% to 29% in LUAD and 22% to 46% in LUSC (p < 0.05). Improved ICI outcomes in PSC appeared driven by high PD-L1 (≥50% in 73%-77% cases). Among patients with high PD-L1, response rates were similar across histologic subtypes. Conversely, TMB was similar in PSC compared with LUAD or LUSC and was not associated with ICI outcomes. Across cohorts, PSC tumors were enriched for TP53, NF1, NF2, and NRAS, with relative depletion of STK11 and KEAP1 compared with LUAD. Case observation revealed relatively better outcomes to ICI than targeted therapies in patients with PSC with MET exon 14 skipping or KRAS G12C. CONCLUSION: PSC exhibits improved outcomes to ICI relative to other therapies, potentially driven by high PD-L1 expression. Genomic analysis highlights a distinct genomic landscape of PSC when compared with LUAD.