Sclerosing pneumocytoma: a host for a typical carcinoid with pleural metastasis – a wolf in sheep's clothing

Sclerosing pneumocytoma (SP) is a rare primary lung tumor. Typical carcinoids (TCs) count for 2% of lung malignancies. A description of a combined neoplasm of SP with a nodal and pleural metastasized TC has, to our knowledge, never been published. A 57-year-old actively smoking woman received a diagnosis of a lesion in the left lower lobe via a screening CT scan for rheumatoid arthritis. A fluorodeoxyglucose-PET scan confirmed a 21 × 26 × 16 mm (standardized uptake maximum value, 3.0), well-circumscribed round lesion with calcification, which was thought to be most probably benign. No mediastinal lymph node enlargement or fluorodeoxyglucose uptake was detected. The results of routine laboratory tests, respiratory function tests, and physical examination were unremarkable. In diagnostic thoracoscopy pleural, diaphragmatic, and pericardial lesions were discovered and biopsied in addition to a wedge resection. After diagnosis of a pleural metastasized TC mixed with SP, radical resection and systemic lymph node dissection were performed. The patient is in remission after 36 months of follow-up.