Diffuse pancreatic serous cystadenoma associated with neuroendocrine carcinoma: a case report and review of literature.

CONTEXT Diffuse serous cystadenomas of the pancreas are extremely rare, with only 8 cases reported previously, and have been associated with neuroendocrine tumors in only two patients. Some have been seen in von Hippel-Lindau disease. The management of these tumors poses a challenge due to their rarity and uncertain malignant potential. We report a case of diffuse serous cystadenoma associated with neuroendocrine carcinoma in a 35-year-old woman. CASE REPORT A 35-year-old woman with mild abdominal pain was diagnosed as having a cystic pancreatic mass on ultrasonography. On contrast-enhanced CT scan, MRI and MRCP imaging, a spongy lesion was found to replace the entire pancreas, and was diagnosed as diffuse serous cystadenoma. Serum biochemistry for amylase, lipase, CA 19-9 and CEA was normal. Screening for retinal and CNS lesions was also unremarkable. A total pancreatectomy was performed, and the patient recovered well. Histopathological examination of the specimen revealed microcysts and macrocysts replacing the entire pancreas, the largest being 3.5 cm. The cysts were lined with a single layer of cuboidal to flattened cells. An endocrine tumor abutting the cystic component was found, having neoplastic cells in a trabecular pattern. Metastasis of the neuroendocrine component was seen in the adherent lymph nodes. A diagnosis of diffuse serous cystadenoma associated with neuroendocrine carcinoma was made. CONCLUSION Diffuse serous cystadenomas of the pancreas are extremely rare tumors. In young patients, they may harbour associated malignancy, and may be the first presentation of von Hippel-Lindau disease. Aggressive surgical resection with long-term follow-up may be worthwhile in this group of patients.