Lazarus Response to Selpercatinib for Bleeding Colic Metastasis in a Patient With RET Fusion-Positive Pulmonary Sarcomatoid Carcinoma: A Case Report.

In recent years, the widespread use of next-generation sequencing (NGS) allowed clinicians to identify and treat non-small cell lung cancer (NSCLC) efficiently with target therapy. RET inhibitors, like selpercatinib and pralsetinib, for RET rearrangements in lung cancer showed high efficacy and clinical benefit. Nevertheless, to date, the use of molecular-targeted agents has not been tested in all lung cancer subtypes. Indeed, pulmonary sarcomatoid carcinoma (PSC) remains a rare form of NSCLC, unresponsive to standard chemotherapy, and associated with extremely poor prognosis. We report the first case of a patient affected by RET fusion-positive PSC with a bleeding colic metastasis and a consequent poor performance status who achieved a dramatic response to selpercatinib and a remarkable clinico-radiological benefit.