# Mixed adenoneuroendocrine carcinoma of the gallbladder: a case report and review of the literature

## TL;DR

A rare case of gallbladder cancer with neuroendocrine features is reported, treated with surgery and chemotherapy, showing no recurrence for one year.

## Contribution

Presents a rare case of gallbladder mixed adenoneuroendocrine carcinoma with treatment and follow-up details.

## Key findings

- The neuroendocrine part of the tumor accounted for 70% and was poorly differentiated with a Ki-67 index of 80%.
- The patient received six cycles of etoposide and cisplatin after surgery and remained disease-free for 12 months.
- Radical resection combined with chemotherapy is suggested as an effective treatment for gallbladder neuroendocrine carcinoma.

## Abstract

Neuroendocrine carcinoma (NEC) is a rare malignant tumor of the gallbladder (GB) and is extremely rare in medical practice. Related case reports and in-depth studies are extremely limited, resulting in an insufficient understanding of the disease. This article reports a case of a 60-year-old female patient who complained of right upper abdominal pain for 20 days. Subsequent examinations confirmed that it was mixed adenoneuroendocrine carcinoma of the gallbladder (GB-MANEC), of which the neuroendocrine part accounted for approximately 70%, and was defined as a poorly differentiated NEC. The Ki-67 index reached 80%, indicating highly aggressive behavior. Postoperative adjuvant chemotherapy was administered (six cycles of etoposide combined with cisplatin). Follow-up through December 2024 showed no signs of tumor recurrence, with a disease-free survival period of 12 months. Currently, the preferred treatment strategy for GB-NEC is radical surgery. Therefore, in this case, radical resection combined with chemotherapy became an effective treatment.