Treatment Response to Immunotherapy After Crizotinib Resistance in a Patient With Pulmonary Sarcomatoid Carcinoma Harboring MET Exon 14 Skipping Mutation: A Case Report

Abstract

Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small cell lung cancer (NSCLC) with poor prognosis. The skipping mutation in exon 14 of MET , an oncogenic driver of NSCLC, occurs more frequently in PSC than other subtypes. Treatment options for patients with PSC include targeted therapies and immunotherapies, while the best treatment regimen has not been established due to limited number of patients. In this report, we presented a case with metastatic PSC harboring MET 14 exon skipping mutation. The patient received crizotinib but soon acquired drug resistance. Then, the patient turned to immunotherapy in combination with chemotherapy and has achieved a progression-free survival for 15 months as of the data cutoff date. The comprehensive genomic sequencing after crizotinib resistance revealed additional genetic alterations such as CD274 (also known as programmed cell death ligand 1) amplification which might be associated with treatment response of the patient.