Anatomy and Surgical Management of Ampullary Neoplasm
Ampulla is a common channel where biliary and pancreatic duct join. The reason why it is called ampulla is that this area is enlarged where it penetrates the duodenal wall. As it protrudes into the duodenal lumen, it is also called papilla. Ampulla is surrounded by sphincter muscles which control the secretion of bile and pancreatic juice. Ampullary tumor includes broad spectrum of benign and malignant tumors which need different treatment options - Endoscopic papillectomy (EP), surgical ampullectomy (SA), and pylorus-preserving pancreatoduodenectomy (PPPD). There is a consensus that benign tumors need EP and malignant tumors need PPPD. However, there are controversies regarding how to treat high-grade dysplasia (HGD), carcinoma in-situ, or T1 cancer. Surgical treatment includes SA and PPPD. The indication of SA is usually benign tumors which extend to bile duct or pancreatic duct or too big tumors to snare completely by endoscopy. Compared to EP, SA is less likely to leave remnant tumor which results in re-resection. In some limited cases of early carcinoma, SA can be attempted. Oncologically, however, SA is not recommended because there might be incomplete resection, lymph node metastasis, lymphovascular invasion, or perineural invasion. As PPPD still has high morbidity, prolonged length of stay, and relatively high post-op mortality, SA can be recommended in old patients with co-morbidity that can be exacerbated after surgery. Technically important points of SA are as follows; first, resecting the whole layer of duodenum, second, re-implanting the bile duct and pancreatic duct with duodenal mucosa to keep the mucosal continuity. PPPD is a standard operation of malignant tumor because it can completely remove the tumor as well as regional lymph nodes.