Gallbladder primary well-differentiated neuroendocrine tumor: A misdiagnosed case

INTRODUCTION: Gallbladder (GB) Well-Differentiated (WD) Neuroendocrine Tumor (NET) are extremely rare tumors. They represent only about 0.5 % of all Neuroendocrine Neoplasms (NENs). Most GB-NETs are diagnosed after cholecystectomy. They are often misdiagnosed and have good prognosis. CASE PRESENTATION: We share our experience of a 42-year-old woman operated on for symptomatic cholelithiasis. We discover on the anatomopathological piece that it was a Grade 1 NET of the GB. Staging scans and octreotide-scans were normal: there is no distant or nodal metastasis. This tumor was classified as T1bN0M0. After multidisciplinary team discussion, additional treatment is deemed unnecessary. She didn't receive any treatment after the surgery. At one year after the cholecystectomy, she is symptom free and there is no sign of recurrence. DISCUSSION: The diagnosis of GB-WD NET is difficult at the first evaluation. Surgical management for GB cancer has shown increased survival rates, a similar strategy seems reasonable for GB-NETs. Patients with Grade,1 well-differentiated GB-NETS have an excellent prognosis overall. CONCLUSION: Research is required to facilitate earlier diagnosis and to develop management guidelines for GB-NETs.