Papillary solid and cystic pancreatic tumor. Genetic prediction factors for malignancy: report of three cases.

BACKGROUND: Papillary solid and cystic pancreatic tumor (PSCPT) is a rare neoplasm of unknown pathogenesis, with an excellent overall prognosis after complete resection. The malignant potential of this tumor remains unclear and was the object of our investigation. PATIENTS AND METHODS: We report three cases of PSCPT submitted to radical resection in which histological and immunohistochemical studies, as well as genetic analysis of Kirsten-ras (K-ras) oncogene mutations, p53 and Fragile Histidine Triad (FHIT) gene expression, were evaluated. RESULTS: Low expression of Ki 67 was consistent with a low karyokinetic index of these tumors. Mutations of the K-ras gene were not present. Low-grade variations of p53, K-ras and FHIT genes were detected by immunohistochemistry. CONCLUSION: PSCPT is a rare neoplasm with low malignancy. Further genetic analysis is required to predict the potential malignancy of this tumor; nevertheless combined multimodality approaches may play a suitable role in identifying more aggressive forms.