ROS1-Rearranged Lung Cancer With Extensive Calcification on Computed Tomography: A Case Report

Although calcified lung cancers are occasionally observed, they are quite rare. We report a case of extensively calcified lung adenocarcinoma with ROS1 fusions. A 57-year-old Japanese woman was initially diagnosed with adenocarcinoma based on aspiration cytology of an enlarged left supraclavicular fossa lymph node at the Department of Otorhinolaryngology at our institution. Subsequent chest imaging suggested primary lung cancer, leading to a referral to the Department of Respiratory Medicine. Computed tomography of the chest revealed a nodular shadow in the right S5 lobe and enlarged mediastinal lymph nodes with extensive calcification. A bronchoscopy with transbronchial lung biopsy of the right S5 nodule confirmed the diagnosis of adenocarcinoma. The biopsy specimen was analyzed using the AmoyDx® Pan Lung Cancer PCR Panel, which detected ROS1 fusions.