Pancreatic metastasis in a case of small cell lung carcinoma: Diagnostic role of fine-needle aspiration cytology and immunocytochemistry

Small cell lung carcinoma represents a group of highly malignant tumors giving rise to early and widespread metastasis at the time of diagnosis. However, the pancreas is a relatively infrequent site of metastasis by this neoplasm, and there are only occasional reports on its fine needle aspiration (FNA) cytology diagnosis. A 66-year-old man presented with extensive mediastinal lymphadenopathy and a mass in the pancreatic tail. Ultrasound-guided FNA smears from the pancreatic mass contained small, round tumor cells with extensive nuclear molding. The cytodiagnosis was metastatic small cell carcinoma. Immunocytochemical staining showed that a variable number of neoplastic cell were positive for cytokeratin, chromogranin A, neurone-specific enolase and synaptophysin but negative for leukocyte common antigen. The trans-bronchial needle aspiration was non-diagnostic, but biopsy was suspicious of a small cell carcinoma. This case represents a rare metastatic lesion in the pancreas from small cell lung carcinoma, diagnosed by FNA cytology.