Case report: intraductal tubulopapillary neoplasm of the pancreas with unique clear cell phenotype

Abstract

Intraductal tubulopapillary neoplasms of the pancreas are very rare tumors characterized by intraductal tubulopapillary growth, ductal differentiation, scant intracellular mucin production and cellular dysplasia. Here, we report the first case of an intraductal tubulopapillary neoplasm of the pancreas with clear cell morphology. The tumor was detected during the diagnostic work-up of acute pancreatitis in a 43- year old female. Histological examination revealed a tumor with the typical architecture of an intraductal tubulopapillary neoplasm of the pancreas with tumor cells showing abundant clear cytoplasm and Di-PAS negativity. Immunohistochemistry revealed positivity for Pan-CK, CK7, CK8/18, MUC1, MUC6, carbonic anhydrase IX, CD10, EMA, β-catenin and e-cadherin. Sanger sequencing did not detect mutations for β-catenin, BRAF, KRAS, PIK3CA and GNAS. Altogether, histology, immunohistochemical expression profile (MUC1+, MUC6+, MUC2-, MUC5AC-, thrypsin-, chymotrypsin-, CDX2-) and sequencing results led to the diagnosis of intraductal tubulopapillary neoplasm. However, the neoplasm consisted of cells showing abundant clear cytoplasm, a morphological pattern not being described so far in the current classification of pancreatic intraductal neoplasms. Potential differential diagnosis and the molecular basis of clear cell morphology are discussed. In conclusion, we consider this tumor as intraductal tubulopapillary neoplasm of the pancreas with unique clear cell phenotype. After surgery and without adjuvant therapy, the patient’s clinical course has been uneventful for over two years now.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1051828790117127

Intraductal Tubulopapillary Neoplasm of the Pancreas Masquerading as Pancreatic Neuroendocrine Carcinoma: Review of the Literature with a Case Report

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Metastatic Renal Cell Carcinoma to the Pancreas: A Review

“…Expressions of HMB-45 and smooth muscle actin support a diagnosis of PEComa, 16 whereas expressions of cytokeratin, CD10, and PAX8 favor a diagnosis of CCRCC. 10 Recently, a clear cell type of intraductal tubulopapillary neoplasm 18 has been described where the tumor closely resembles a metastatic CCRCC to the pancreas and exhibits a proliferation of clear cells within the pancreatic duct. The mimicry is further heightened by the neoplasm's ability to react positively to antibodies against carbonic anhydrase IX and CD10 on immunohistochemistry.…”

A case of intraductal tubulopapillary neoplasm of pancreas with severe calcification, a potential pitfall in diagnostic imaging

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