Rare Mixed Adenoneuroendocrine Carcinoma of the Gallbladder: Case Report and Review of Literature

A comprehensive exploration of gallbladder health: from common to rare imaging findings

This comprehensive review explores a wide range of imaging findings associated with the gallbladder (GB), from anatomic variants to rare diseases. Through an in-depth review of diagnostic modalities including ultrasound, magnetic resonance cholangiopancreatography, CT, and MRI, we aim to highlight the crucial role of imaging techniques in diagnosing GB disorders, as congenital anomalies, inflammatory diseases, neoplasms, and surgical complications. Employing a detailed analysis and comparison of imaging findings across various modalities, this review seeks to improve diagnostic accuracy for GB-related pathologies, facilitating optimal patient management.

Comprehensive analysis of mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs): A SEER database analysis of 767 cases

Background

Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is an extremely rare entity, consisting of neuroendocrine and non-neuroendocrine components. It can occur in various organs throughout the body, with a rising incidence. Its clinical management is a rapidly growing field of interest; however, large-scale patient cohorts are still missing to guide clinical practice.

Patients and methods

The demographic, clinicopathological, and survival information of all patients diagnosed with MiNEN in the national Surveillance, Epidemiology, and End Results (SEER) program database (2000-2017) were extracted and further analyzed. The information of the patients before and after 2010 was compared to understand the epidemiological changes of MiNEN. The characteristics of MiNEN originating in different organs were compared. The clinical significance of surgical resection for metastatic MiNENs was also analyzed.

Results

A total of 1081 patients were screened, and after applying the exclusion criteria, 767 patients were finally analyzed. There was no obvious sex preference (49.2% vs 50.8%, p>0.05) and the majority of the patients were Caucasians (n=627, 81.7%). A total of 88.3% of the patients were older than 50 years old, and the median age was 60 years. 79.3% of the tumors are located in the distal digestive tract, and 67.7% were grade 3/4. Distant metastasis was presented in 33.9% of the patients at diagnosis. A total of 88% of the patients underwent surgical treatments. The number of patients increased 10-fold between 2000 and 2017. There was no significant difference in sex, race, stage, or surgical treatments among the patients diagnosed before and after 2010. More patients older than 60 years were diagnosed after 2010 (p=0.009). The median survival was 61.0 ± 9.8 months for the whole cohort. After multivariate analysis, older age (>60 years, p<0.01), more advanced stage (p<0.01), grade 3/4 (p<0.01), and non-surgical treatment (p<0.01) were independent risk factors for poorer survival. The appendiceal MiNENs showed the best prognosis. A total of 260 metastatic MiNENs were further analyzed. Only patients with metastatic MiNENs originating from the appendix had a potential benefit from surgical resection, compared to other sites (p=0.05).

Conclusion

This study provides the epidemiological, clinicopathological, and survival information of the largest number of MiNEN patients. Although MiNEN is an extremely rare malignant neoplasm, its incidence increases rapidly. The majority of the patients suffered from advanced-stage disease, which highlights the need for improvement of early detection in the future. The appendix is the most common primary site of MiNEN, and surgical resection for selected metastatic MiNEN originating in the appendix has favorable survival outcomes.

Focal neuroendocrine carcinoma mixed with adenocarcinoma of the gallbladder with aggressive lymph node metastasis in a patient who did not meet the mixed neuroendocrine-non-neuroendocrine neoplasm criteria

A 70-year-old Japanese woman who was treated for interstitial pneumonia (IP) with steroid therapy developed cholecystitis. A serial computed-tomography (CT) imaging showed irregular thickness of the fundus wall of the gallbladder and two rapidly enlarged lymph nodes (LNs): number (no.) 12 and no. 8a. Positron-emission tomography-computed tomography (PET-CT) scan showed an abnormal uptake at the site of the gallbladder tumor and those LNs. We subsequently performed open radical cholecystectomy and LN dissection of the no. 12 and 8a LNs, following complete remission of IP. The histology showed gallbladder adenocarcinoma, with a single focus of neuroendocrine carcinoma (NEC) component of less than 30%; Ki-67 index > 80%, synaptophysin (Syn) (+), chromogranin A (CgA) (+), and clusters of differentiation (CD) 56 (+) (T2bN1M0, Stage IIIB). LN no. 8a was diffusely metastatic with NEC components. LN no. 12c, which was adjacent to the cystic duct, revealed necrosis without apparent tumor cells, but was highly suspicious for tumor necrosis. The final diagnosis was adenocarcinoma of the gallbladder with focal NEC (< 30%), which did not meet the criteria for mixed neuroendocrine–non-neuroendocrine neoplasm (MiNEN). Postoperatively, she completed 4 cycles of adjuvant chemotherapy for NEC (Cisplatin plus Etoposide), and no recurrence was observed after 12 months.