Synchronous Multiple Primary Cancers of the Lung: The Rare Association of Non-Small Cell Carcinoma With a Carcinoid Tumor.

A 68-year-old female patient diagnosed with lung cancer in the left upper lobe with associated mediastinal adenopathy. The cancer was pathologically diagnosed as stage pT1bN0 typical carcinoid. Investigation of the mediastinal lymph nodes revealed an isolated metastatic non-small cell squamous cell carcinoma (NSCLC). A primary NSCLC was not found. The patient underwent successful surgical resection of both synchronous tumors, with no residual disease or recurrence. This case not only expands the histological field of combined neuroendocrine tumors, but it also highlights the importance of distinguishing various tumor types for disease treatment and prognosis.