Pancreatic Pathology Online - Clear Cell (Sugar) Tumour of the Pancreas

Clear cell "sugar" tumour of the pancreas is an extremely rare tumour

which resembles clear cell 'sugar' tumour of the lung.

Visit: Pancreatic Pathology Online ; Exocrine Pancreatic Tumours ;

Clear cell sarcoma & PEComas .

Gross features: Well-demarcated nodular lesion.

Microscopic features: The resected tumour consist of a population of

large epithelioid cells with clear or eosinophilic, granular cytoplasm,

rich in glycogen, with nuclear pleomorphism and there is no mitotic

activity.

The epitheloid cells with clear cytoplasm are grouped around

sinusoidal vessels.

The immunostaining pattern resemble those described in clear cell

"sugar" tumour of the lung i.e. immunoreactivity with melanoma

associated antigen HMB-45 and actin.

The tumour cells are negative for cytokeratin, NSE, chromogranin A,

lipase, amylase.

Tumour arises from perivascular epithelioid cells, which also cause

lymphangioleiomyomatosis and angiomyolipoma .

Differential diagnosis: Clear cell carcinoma of the Pancreas

"Sugar" tumor of the pancreas: a rare entity that is diagnosable on preoperative fine-needle biopsies. Virchows Arch. 2005 May;446(5):555-9.

This study is the second to report a pancreatic "sugar" tumor (ST) case. This ST was incidentally discovered in a 31-year-old woman using computed tomography scan (CT scan) for work-up of a hepatic focal nodular hyperplasia. Both CT scan and endoluminal ultrasonography (EUS) features evoked a 15-mm large benign endocrine tumor. Pathological examination of EUS-guided fine-needle aspiration biopsies could not confirm this diagnosis. Laparoscopic corporeo-caudal pancreatectomy was performed. The tumor was intrapancreatic, well circumscribed, and organized in sheets of epithelioid cells. The tumor cells expressed HMB-45 but did not express epithelial or endocrine immunohistochemical markers. These histophenotypic features are those of an extra pulmonary ST, which belong to the PEComa family of tumors. Retrospective examination of preoperative biopsies evidenced the same histophenotypic features. This observation highlights that STs should be considered in preoperative differential diagnosis of pancreas tumors, since they may be treated by limited surgical resection.

Clear cell "sugar" tumor of the pancreas. A novel member of the family of lesions characterized by the presence of perivascular epithelioid cells.
Am J Surg Pathol. 1996 Jun;20(6):722-30.

We report at unique, previously unreported pancreatic tumor occurring in a 60-year-old woman who was preoperative diagnosed on cytoaspiration as having clear cell carcinoma. The resected tumor consisted of a population of large epithelioid cells with clear or eosinophilic, granular cytoplasm, rich in glycogen, with nuclear pleomorphism and no mitotic activity. In spite of the epithelioid appearance, the tumor cells were negative for epithelial (CAM 5.2, KL1, AE1-AE3), endocrine (neuron-specific enolase [NSE], chromogranin A), and acinar (lipase, amylase) markers and positive for actin and melanogenesis-related marker HMB 45. Ultrastructurally, the neoplastic cells showed membrane-bound granules; no evidence of either epithelial or melanocytic differentiation was present. These morphophenotypic features have never been reported in a pancreatic tumor and overlap those of clear cell "sugar" tumor of the lung. The same morphophenotypic features are observed in a family of lesions characterized by the presence of the perivascular epithelioid cell that also includes lymphangiomyomatosis and angiomyolipoma. The present case may be considered a novel member of this family of lesions. We propose this new entity be named clear cell "sugar" tumor of the pancreas.