Duodenal Periampullary Gangliocytic Paraganglioma: Report of Two Cases with Immunohistochemical and Ultrastructural Study

Abstract

We report two cases of Gangliocytic Paraganglioma (GP) of the ampulla of Vater occurring in a 63-year-old and a 34-year-old individual. The patients were both admitted for a long history of intermittent gastrointestinal bleeding and abdominal discomfort, with no other symptoms. At endoscopy, the GP appeared as a polypoid, ulcerated mass in the ampullar region, measuring 2.5x1.8 and 2 cm, respectively. Microscopically, the tumors showed similar features and were composed of epithelial cells (more than 50%), spindle cells, and ganglion-like cells. The epithelial cells showed clear cytoplasm and formed nests (zellballen or paraganglioma-like groups), and less frequently, cords (carcinoid-like), extending to mucosa and submucosa. Ganglion cells were sparse, constantly associated with the spindle cells. Both epithelial and ganglion cells were synaptophysin, chromogranin A, and anti-neurofilament immunoreactive. The spindle cells were all S-100 positive. Ultrastructural studies revealed dark and light cells, rare elongated cellular processes, secretory granules, and fine fibrils resembling neurofilaments. The histogenesis of GP is still a matter of debate, however its neoplastic nature is supported by the occasionally reported malignant evolution.

Well-Differentiated Duodenal Tumor/Carcinoma (Excluding Gastrinomas)

“…They characteristically contain gangliocytic differentiation and S-100 protein immunoreactive Schwann cells [26, 75]. They also show positive staining for NSE in 94–100%, PGP 9.5 in 100%, synaptophysin in 94–100%, S-100 in 90%, PP in 75–92%, serotonin in 48–69%, chromogranin in most series in 10–15% and infrequently (<1%) calcitonin, gastrin or ACTH [4, 40, 75, 76]. …”

Duodenal gangliocytic paraganglioma with lymph node metastasis and an 8-year follow-up

“…Hence, it has the features of a ganglioneuroma, a paraganglioma, and a carcinoid tumor [22][23][24]. At immunohistochemical analysis, spindle cells are immunoreactive to S-100, synaptophysin, NSE, and antineurofilaments; ganglion cells are immunoreactive to NSE, synaptophysin, antineurofilaments, chromogranin A, pancreatic polypeptide, and somatostatin; and neuroendocrine cells are immunoreactive to chromogranin A, synaptophysin, antineurofilaments, cytokeratin, somatostatin, NSE, and pancreatic polypeptide [1,3,7,22]. However, lymph node metastases generally include only neuroendocrine epithelial cells, supporting the idea that this cellular component is the only one with malignant potential [2,3].…”

“…In 95% of the cases, the tumor is symptomatic, with 60% of patients presenting with melena [18][19][20] or abdominal pain [21]. Obstruction of the upper digestive tract [6] and obstructive jaundice are uncommon [8,18,22]. Endoscopic examination shows a single pedunculated or a sessile polypoid mass with a smooth or an ulcerated surface [3,18].…”

A Rare Cause of Melaena-Duodenal Gangliocytic Paraganglioma

“…Grossly, GP may present as single polypoid, sessile, pedunculated or multiple masses [2]. Tumour size ranges from 5.5 to 100 mm [5].…”

“…Gangliocytic paraganglioma (GP) is an uncommon tumour of the gastrointestinal tract with majority of cases arising in the duodenum [2]. Other reported sites include the jejunum, pylorus, oesophagus, pancreas and appendix [3].…”