Mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater: a case report

BACKGROUND

Mixed neuroendocrine-non-neuroendocrine neoplasms of the ampulla of Vater are rare and heterogenous, making it difficult to achieve a definitive preoperative diagnosis. Herein, we describe a patient in whom a provisional diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater was made preoperatively.

CASE PRESENTATION

Computed tomography revealed an enhancing periampullary tumor in a 69-year-old man with obstructive jaundice. Subsequent duodenoscopy revealed an ulcerated lesion in the swollen ampulla of Vater, from which six biopsies were collected. Pathological examination revealed adenocarcinoma in five of them. The remaining one was a neuroendocrine neoplasm according to immunohistochemical analysis. With a provisional diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater, the patient underwent subtotal stomach-preserving pancreaticoduodenectomy with modified Child's reconstruction and was discharged without complications. Pathological examination revealed both adenocarcinoma and neuroendocrine carcinomas, each accounting for ≥ 30% of the tumor, resulting in a definitive diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater. Lymph node metastases with neuroendocrine components were also observed. Adjuvant chemotherapy was not administered because of the patient's renal dysfunction. Liver and lymph node metastases were detected 2 months after surgery, the neuroendocrine component being considered responsible for that relapse. The patient underwent platinum-based chemotherapy at 50% dosage, which initially resulted in significant tumor shrinkage; however, he died 6 months after surgery.

CONCLUSIONS

While these tumors' heterogeneity make definitive preoperative diagnosis of mixed neuroendocrine-non-neuroendocrine neoplasm of the ampulla of Vater difficult, the possibility of this disease can be considered by careful examination. Further study is needed to establish the optimal diagnostic criteria and treatment strategy.

CT and MR imaging features of mixed neuroendocrine-non-neuroendocrine neoplasm of the pancreas compared with pancreatic ductal adenocarcinoma and neuroendocrine tumor

OBJECTIVE

This study aimed to assess the computed tomography (CT) and magnetic resonance imaging (MRI) features of pancreatic mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) and compare them with those of pancreatic ductal adenocarcinoma (PDAC) and neuroendocrine tumor (NET).

METHODS

Twelve patients with pancreatic MiNEN, 24 patients with PDAC, and 24 patients with NET, who underwent both contrast-enhanced CT and MRI, were included. Clinical data and the key imaging features were retrospectively evaluated by two independent readers and compared between MiNEN and PDAC or NET. Univariate and multivariable logistic regression analyses were performed to obtain predictors for pancreatic MiNEN.

RESULTS

Patients with pancreatic MiNEN more frequently presented with large size and heterogeneous and cystic components compared with PDAC (p < 0.031) and ill-defined irregular margins, progressive enhancement, and adjacent organ involvement compared with NET (p < 0.036). However, vascular invasion was less commonly seen in MiNEN than PDAC (p = 0.010). Moderate enhancement was observed more frequently in MiNEN than in PDAC or NET (p < 0.001). Multivariate logistic analyses demonstrated that moderate enhancement and ill-defined irregular margin were the most valuable features for the prediction of pancreatic MiNEN (p ≤ 0.044). The combination of the two features resulted in a specificity of 93.8%, sensitivity of 83.3%, and accuracy of 91.7%.

CONCLUSIONS

We have mainly described the radiological findings of pancreatic MiNEN with ill-defined irregular margin and moderate enhancement compared with PDAC and NET. The combination of imaging features could improve diagnostic efficiency and help in the selection of the correct treatment method.

Mixed neuroendocrine-non-neuroendocrine neoplasm of the gallbladder: case report and literature review

Background

Mixed neuroendocrine–non-neuroendocrine neoplasms (MiNENs) of the gallbladder are rare malignancies. Here we presented two cases and reviewed the related literature.

Case presentation

Our two patients were postoperatively diagnosed with gallbladder MiNENs, which pathologically consisted of a large cell neuroendocrine carcinoma and papillary adenocarcinoma. After cholecystectomy, one patient had a survival time of 30 months, while the other remained alive through 12 months of follow-up. In the literature, a total of 72 cases of gallbladder MiNENs were identified, and with our two patients included, we calculated a male-to-female ratio of 0.22 and a mean age of 64.5 years for the 74 reported cases. About one-half of these patients were found to have gallstones and presented with abdominal pain or discomfort in a relatively early stage. The preoperative diagnosis of these 74 cases mainly relied on abdominal ultrasound, contrast-enhanced computed tomography (CT) scanning, and magnetic resonance imaging or positron emission tomography/CT. However, the final diagnosis was established based upon the pathological evidence and expression of synaptophysin (Syn) and/or chromogranin A identified by immunohistochemical staining or neurosecretory granules detected by electron microscopy. Fifty-eight patients (78.4%) underwent various operations including simple cholecystectomy (n = 14), en bloc cholecystectomy (n = 9), standard or non-standard radical cholecystectomy (n = 25), or extended radical cholecystectomy (n = 6). The mean size of the resected gallbladder masses was 50.8 ± 36.1 mm (n = 63) with regional lymph node metastasis in 37 patients (52.1%), liver invasion or staging greater than T3 in 33 patients (45.8%), and hepatic metastasis in 26 patients (35.1%). The postoperative median survival time was 36 ± 11.42 months (95% confidence interval, 13.62 to 58.38 months). The log-rank analysis did not find that postoperative adjuvant chemotherapy contributed to a longer survival time relative to that among the patients who did not receive chemotherapy (numbers of patients, 15 versus 43; survival times, 36 months versus 30 months, p > 0.05).

Conclusions

Our two cases and the cases in the literature suggest that MiNENs of the gallbladder predominantly occur in women; are associated with early lymph node metastasis, local hepatic invasion, and hepatic metastasis; and can be managed by various surgeries as well as chemotherapy combined with somatostatin analogs.