Neurofibromatosis 1 presenting with multiple duodenal GISTS associated with a somatostatin-producing D cell neoplasm

Neuroendocrine Tumors (NETs) of the Minor Papilla/Ampulla: Analysis of 16 Cases Underlines Homology With Major Ampulla NETs and Differences From Extra-Ampullary Duodenal NETs

Neuroendocrine tumors (NETs) of the minor papilla/ampulla (MIPA) are rare and poorly studied. Only individual case reports and no comprehensive analysis are available from the literature. We collected 16 MIPA NETs and investigated their clinicopathologic and immunohistochemical features, including markers such as somatostatin, pancreatic polypeptide, gastrin, serotonin, MUC1, cytokeratin 7, and somatostatin receptors type 2A and 5. The median age at diagnosis was 57.5 years, and the female-to-male ratio was 2.2:1. The median NET size was 1.45 cm, and most (94%) were low-grade (G1) tumors. Similarly to what was observed in the major ampulla, 3 histotypes were found: (i) ampullary-type somatostatin-producing tumors (ASTs, 10 cases), characterized by somatostatin expression in most tumor cells, focal-to-extensive tubulo-acinar structures, often with psammoma bodies, MUC1 reactivity, and no or rare membranous reactivity for somatostatin receptor type 2A; (ii) gangliocytic paragangliomas (3 cases), characterized by the coexistence of 3 tumor cell types: epithelioid, often reactive for pancreatic polypeptide, ganglion-like cells, and S100 reactive sustentacular/stromal cells; and (iii) ordinary nonfunctioning NETs (3 cases), resembling those more commonly observed in the extra-ampullary duodenum. Comparable histotypes could also be recognized among the 30 MIPA NETs from the literature. No NET-related patient death among MIPA cases was observed during a median follow-up of 38 months; however, MIPA ASTs showed lymph node metastases and invasion of the duodenal muscularis propria or beyond in 44% and 40% of cases, respectively. In conclusion, MIPA NETs closely resemble tumors arising in the major ampulla, with predominance of ASTs.

Clinicopathological features, surgical strategy and prognosis of duodenal gastrointestinal stromal tumors: a series of 300 patients

BACKGROUND

The relatively low incidence of duodenal gastrointestinal stromal tumors (GISTs) and the unique anatomy make the surgical management and outcomes of this kind of tumor still under debate. Thus, this study aimed to explore the optimal surgical strategy and prognosis of duodenal GISTs.

METHODS

A total of 300 cases of duodenal GISTs were obtained from our center (37 cases) and from case reports or series (263 cases) extracted from MEDLINE. Clinicopathological features, type of resections and survivals of duodenal GISTs were analyzed.

RESULTS

The most common location of duodenal GISTs was descending portion (137/266, 51.5%). The median tumor size was 4 cm (0.1-28). Most patients (66.3%) received limited resection (LR). Pancreaticoduodenectomy (PD) was mainly performed for GISTs with larger tumor size or arose from descending portion (both P < 0.05). For both the entire cohort and tumors located in the descending portion, PD was not an independent risk factor for disease-free survival (DFS) and disease-specific survival (DSS) (both P > 0.05). Duodenal GISTs were significantly different from gastric GISTs with respect to tumor size, mitotic index and NIH risk category (all P < 0.05). The DFS and DSS of duodenal GISTs was significantly worse than that of gastric GISTs (both P < 0.05).

CONCLUSIONS

LR was a more prevalent surgical procedure and PD was mainly performed for tumors with larger diameter or located in descending portion. Type of resection was not an independent risk factor for the prognosis of duodenal GISTs. Prognosis of duodenal GISTs was significantly worse than that of gastric GISTs.

Rectal carcinoma and multiple gastrointestinal stromal tumors (GIST) of the small intestine in a patient with neurofibromatosis type 1: a case report

Background

Neurofibromatosis type 1 (NF1) is an autosomally dominant inherited disorder characterized by multiple pigmented skin spots (café-au-lait spots) and neurofibroma. NF1 is associated with a wide variety of benign or malignant tumors. We report a NF1 patient who received surgical treatment for rectal carcinoma and multifocal small intestinal gastrointestinal stromal tumors (GISTs).

Case presentation

A 70-year-old female patient with NF1 was referred to our hospital after a positive fecal occult blood test. Locally advanced rectal carcinoma was detected in the upper rectum using colonoscopy. A submucosal tumor 20 mm in diameter was detected in the duodenal bulb during the upper gastrointestinal endoscopy. The biopsy specimen from the duodenum was GIST with positive immunostaining of KIT and CD34 microscopically. Laparoscopic low anterior resection for rectal carcinoma and local excision of the duodenal GIST were performed successfully. During the operation, five white small nodules were found on the serosa of the jejunum. One nodule was excised for histological examination. The resected rectal tumor was a well-differentiated adenocarcinoma with multiple lymph nodes metastases according to the histology. The duodenal tumor was found to be low-risk GIST. Moreover, the nodule from the jejunum was very low risk GIST. An excised skin wart was neurofibroma according to the histology.

Conclusions

GIST or carcinomas have been reported to occasionally occur in the digestive tract of the patients with NF1. We present a rare case of a NF1 patient with GISTs and colorectal carcinoma.

Somatostatin-Immunoreactive Pancreaticoduodenal Neuroendocrine Neoplasms: Twenty-Three Cases Evaluated according to the WHO 2010 Classification

BACKGROUND/OBJECTIVE

Neuroendocrine neoplasms of the pancreas and duodenum with predominant or exclusive immunoreactivity for somatostatin (pdSOMs) are rare, and knowledge about tumour biology, treatment, survival and prognostic factors is limited. This study aims to describe clinical, pathological and biochemical features as well as treatment and prognosis of pdSOMs.

DESIGN

Twenty-three patients with pdSOM (9 duodenal, 12 pancreatic and 2 unknown primary tumours) were identified from our prospective neuroendocrine tumour database, and data according to the study aims were recorded.

RESULTS

Among the 9 patients with duodenal SOM, the male/female ratio was 4/5. All males and 1 female had neurofibromatosis type 1. Seven patients had stage 1A/B and 2 had stage 2B disease. The Ki-67 index was 1-5% (median 2%). Plasma somatostatin was elevated in the patients with 2B disease. Of the 14 patients with pancreatic SOM or an unknown primary tumour, the male/female ratio was 2/12. One male had multiple endocrine neoplasia type 1. Five had stage 1A/2B and 9 had stage 4. The Ki-67 index was 1-40% (median 7%). Plasma somatostatin was elevated in 7 patients. Patients reported symptoms related to the somatostatinoma syndrome, but none fulfilled the criteria for a full syndrome. Primary tumour in the pancreas, metastatic disease at diagnosis and higher tumour grade were all associated with significantly poorer survival.

CONCLUSION

None of the patients with pdSOM presented with the full somatostatinoma syndrome. Prognostic factors are localisation of the primary tumour, dissemination and tumour grade. A Ki-67 index of 5% may discriminate the course of the disease.