Mixed Adenoneuroendocrine Carcinoma Arising in a Papillary Adenoma of Gallbladder

Abstract

Introduction: Neuroendocrine carcinoma and mixed adenoneuroendocrine carcinoma (MANEC) in the gallbladder are rare. Here, we reported an unusual case of a mixed high-grade neuroendocrine carcinoma and adenocarcinoma, arising in a papillary adenoma with high-grade dysplasia.

Presentation of case: The patient, a 73 year-old woman, had a cholecystectomy for chronic calculous cholecystitis, in which a mixed high-grade neuroendocrine carcinoma and adenocarcinoma arising in a papillary adenoma with high-grade dysplasia was incidentally noted. The carcinoma invaded into lamina propria, without any evidence of invasion into muscularis layer or perimuscular soft tissue, hence was pathologically staged as T1. The patient was treated with chemoradiation after cholecystectomy. Desspite the unusually low tumor stage at presentation of this rare tumor, there were four recurrences / metastases involving abdominal wall, an unusual site for this tumor, which were treated with surgery and / or chemotherapy. The patient is alive with metastatic disease at 45 months after initial cholecystectomy.

Conclusion: We detail the unusual presentation of a mixed high-grade neuroendocrine carcinoma and adenocarcinoma arising in a papillary adenoma with high-grade dysplasia, which sheds some light on the clinical course of this rare tumor.