Periampullary carcinoid tumor

Screening upper endoscopy in an asymptomatic 71-year-old man revealed a protruding periampullary tumor that was covered with intact duodenal mucosa (Figure [1]). Biopsy specimens from this lesion revealed carcinoid tumor. Endoscopic ultrasound demonstrated an echo-poor mass, 15 mm in diameter, in the mucosa. Abdominal computed tomography and magnetic resonance imaging studies showed that there were no metastases to the lymph nodes or to the liver. Endoscopic retrograde cholangiopancreatography was performed and this showed that there was no extension of the tumor into the common bile duct or into the pancreatic duct. The tumor was elevated by submucosal injection of hypertonic saline-epinephrine, and an endoscopic mucosal resection was then successfully performed with no complications.

Figure 1 Endoscopic examination revealed a protruding periampullary tumor covered with intact duodenal mucosa.

Macroscopically, the lesion consisted of a discrete mass within the mucosal layer that was found to be composed of multiple nests of small cells (Figure [2]). Microscopically, these cells were found to consist of an eosinophilic cytoplasm, and uniform, oval, hyperchromatic nuclei that showed no atypia or mitotic activity. Immunohistochemically, the tumor cells were diffusely positive for somatostatin, but negative for insulin and gastrin. Based on these histological findings, we finally diagnosed this lesion as a carcinoid tumor (a well-differentiated endocrine tumor). The resection margins were all tumor-free. Surveillance duodenoscopy at 6 months revealed no macroscopic or microscopic evidence of tumor recurrence (Figure [3]).

Figure 2 Specimens from the endoscopic resection revealed a discrete mass within the mucosal layer, composed of multiple nests of small cells.

Figure 3 Surveillance duodenoscopy 6 months after resection of the carcinoid tumor revealed no macroscopic evidence of tumor recurrence.

Previous studies of patients with ampullary carcinoids have reported that tumor size has no prognostic implications; in addition, no correlation could be identified between mitotic activity and metastatic potential [1] [2] [3]. The tumors that were included in the carcinoid group were predominantly well-differentiated endocrine tumors, and the prognosis was reported to be excellent, with an overall 5-year survival rate of 90 % [1] [3]. Local resection showed satisfactory results in tumors measuring less than 2 cm [3] [4]. Although the method of treatment for ampullary carcinoid tumors with a diameter of less than 2 cm, no invasion of the muscularis propria, and no evidence of metastases remains controversial, endoscopic resection could be considered as a possible treatment modality as long as a strict follow-up protocol is adhered to, as in our case.

Endoscopy_UCTN_Code_CCL_1AB_2AZ_3AB

References

• 1 Hartel M, Wente M N, Sido B. et al . Carcinoid of the ampulla of Vater.  J Gastroenterol Hepatol. 2005;  20 676-681
• 2 Makhlouf H R, Burke A P, Sobin L H. Carcinoid tumors of the ampulla of Vater: a comparison with duodenal carcinoid tumors.  Cancer. 1999;  85 1241-1249
• 3 Hatzitheoklitos E, Buchler M W, Friess H. et al . Carcinoid of the ampulla of Vater: clinical characteristics and morphologic features.  Cancer. 1994;  73 1580-1588
• 4 Ricci J L. Carcinoid of the ampulla of Vater: local resection or pancreaticoduodenectomy.  Cancer. 1993;  71 686-690