188 A Case of Metastatic Serous Cystadenocarcinoma with a Mutational Variant of the von Hippel-Lindau Gene

Introduction/Objective Serous cystadenomas of the pancreas are typically benign neoplasms but a small subset of cases can demonstrate malignant behavior. Histological differentiation between benign serous cystadenoma and malignant serous cystadenocarcinoma is challenging, with metastasis beyond the pancreas being diagnostic for serous cystadenocarcinoma. To date, fewer than 30 cases of serous cystadenocarcinomas have been reported. In addition, pancreatic serous cystic neoplasms have been associated with VHL pathway alterations. Methods/Case Report We report the case of a 66-year-old woman with pancreatic serous cystadenocarcinoma who was diagnosed with multifocal liver metastasis seven years following tumor resection. Core biopsy of the liver mass revealed a multicystic neoplasm lined by a single layer of uniform, cuboidal epithelial cells exhibiting clear-to-eosinophilic cytoplasm and small, round nuclei. The tumor cells were immunopositive for cytokeratin AE1/AE3, inhibin, CAIX, and PAS. Next-generation sequencing identified a missense mutation of VHL (c.343C>A, p.H115N) of uncertain significance. Results NA Conclusion Metastatic pancreatic serous cystadenocarcinomas are extremely rare and no consensus on treatment exists since these tumors exhibit indolent behavior despite metastasizing beyond the pancreas. Reported cases, such as this, highlight the need for consideration of the malignant potential of serous cystic neoplasms in the diagnosis and management of these patients.