Acinar Cell Carcinoma of the Pancreas: A Case Associated With the Lipase Hypersecretion Syndrome

Acinar cell carcinoma is a rare primary tumor of the pancreas that exhibits evidence of acinar differentiation in the form of enzyme production, in addition to having characteristic histologic features. A case is presented that demonstrates the uncommon lipase hypersecretion syndrome, characterized by subcutaneous fat necrosis caused by lipase secreted by the tumor cells. The presence in this case of the syndrome in the absence of hepatic metastases is unusual and perhaps is explained by the large size of the primary tumor (17 cm). The tumor exhibited the typical hypercellular pattern, with a solid and acinar architecture. An unusual degree of nuclear pleomorphism was focally noted. Enzyme production by the tumor cells was demonstrated immunohistochemically with stains for trypsin, chymotrypsin, and lipase, and electron microscopic analysis revealed zymogen granules. The patient lived 18 months after surgical resection, which is a typical course for acinar cell carcinoma, an aggressive tumor with a slightly better prognosis than ductal adenocarcinoma of the pancreas.