ROS1 rearranged pulmonary sarcomatoid carcinoma: A rare clinical presentation

Pulmonary sarcomatoid carcinoma (PSC) is a rare type of non-small cell lung cancer which contains poorly differentiated cells and sarcoma or sarcomatoid components (spindle and/or giant cells). Most of the cases are peripherally located and usually present as a large lung mass. We report a case of PSC in a 42-year-old male with massive pleural effusion as initial presentation. Therapeutic pleurocentesis showed exudative lymphocyte predominant pleural fluid. The diagnosis of PSC could be arrived at with medical thoracoscopy, biopsy and immunohistochemical staining. The next generation sequencing assay of gene panel revealed ROS1 positive status. The patient responded well to crizotinib, till the last follow-up of 21 months from the start of treatment.