Carcinoid tumor of the duodenum: a rare tumor at an unusual site. Case series from a single institution.

BACKGROUND

Duodenal carcinoids are extremely rare, and their characteristics and biological behavior have not been fully elucidated.

OBJECTIVE

To analyze the clinicopathological characteristics of patients with resected duodenal carcinoids.

METHODS

Twenty patients (12 females and 8 males) were investigated. Their average age was 66.4 ± 5.8 years old (43 to 88 years old). The data corresponding to the clinical picture, diagnosis, treatment, and prognosis of patients with duodenal carcinoid tumors subjected to resection over a period of 18 years (1993-2011) were analyzed.

RESULTS

The most common symptoms were dyspepsia (50%) and epigastric pain (45%) followed by weight loss (10%) and vomiting (5%). Carcinoid syndrome was not observed in any patient. The lesion was located on the first part of the duodenum in 15 (75%) patients, the second part in 4 (20%) patients, and the third part in 1 (5%) patient. The diagnosis of a carcinoid tumor was established through an endoscopic excision biopsy in 19 (95%) patients and an histopathological examination of the surgical specimen in 1 (5%) patient. The average tumor size was 1.1 cm ± 0.4 cm (0.3 cm to 6.0 cm). Nineteen (95%) patients were initially treated by endoscopic resection of the duodenal lesion. One patient (5%), whose tumor was on the third part of the duodenum underwent a duodenectomy of the third and fourth duodenal parts and duodenojejunal anastomosis. The duodenal carcinoid resection margin was involved in four (20%) patients. Four (20%) patients were subjected to a partial gastrectomy to fully remove the lesion. The tumor was restricted to the submucosal layer in 16 (80%) cases, and it penetrated into the muscular layer in 4 (20%) cases. All patients exhibited positive chromogranin A, neuron-specific enolase, and/or synaptophysin immunostaining. The average duration of the follow-up period was 39.6 months (3 to 96 months). Twelve (60%) of the 20 cases in this series are alive without any evidence of active disease. Only one (5%) patient died due to liver metastases of the duodenal carcinoid.

CONCLUSIONS

Duodenal carcinoids are rare and indolent tumors usually associated with a benign progression. Duodenoscopy, computerized tomography, and endoscopic ultrasound should be performed to evaluate the tumor size, the level of wall invasion, and the presence of regional or distant lymphatic metastases. Endoscopic removal of tumors smaller than 1.0 cm without periampullary localization or evidence of muscular propria layer invasion assessed by histology and/or endoscopic ultrasound is recommended. The endoscopic resection with a carcinoid tumor size between 1.0 cm and 2.0 cm can be incomplete and require new endoscopic resection or even surgical removal. Duodenal carcinoid larger than 2.0 cm require full-thickness resection and concomitant lymphadenectomy.