Clear cell carcinoma of the pancreas: An adenocarcinoma with ductal phenotype

Aims: Primary clear cell carcinoma of the pancreas resembling metastatic renal carcinoma has only rarely been described. To date it has been poorly characterized as a distinct tumour entity. Methods and results: We report a case of clear cell carcinoma in a 53-year-old man involving the head of the pancreas and which had a small intraductal papillary component. The clear cell portion comprised about 90% of the tumour mass. It showed predominantly a solid growth pattern with a few scattered tubular structures. Immunocytochemically the tumour cells stained positively for cytokeratins 7, 8, 18 and 19, whereas the reaction for vimentin and neuroendocrine markers was negative. K-ras analysis revealed a point mutation at codon 12 with mutation of GGT to GAT. Conclusion: The intraductal tumour component of this clear cell carcinoma as well as the cytokeratin pattern and the K-ras mutation suggest that this rare type of pancreatic cancer has a ductal phenotype.