Gastric Tubular Adenomas Five Years After Total Proctocolectomy in Familial Adenomatous Polyposis: 2355

Familial Adenomatous Polyposis (FAP) is an autosomal dominant syndrome caused by mutations in the Adenomatous polyposis c (APC) gene. The prevalence of FAP ranges from 1 in 6, 850 to 1 in 31,250 births.Guidelines suggest FAP patients should start the surveillance process for colorectal cancer around age 10-12.However, endoscopy to look for FAP-like extra-colonic manifestations is recommended to start at age 25-30. Patients with FAP frequently have gastric polyps which could be fundic gland polyps and tubular adenomas, however it is uncommon to have mostly gastric tubular adenomas. A 23-yearold female with a past medical history of FAP presented for gastrointestinal surveillance. The patient's mother had FAP and thus the patient was screened for APC gene mutation which turned out to be positive. She underwent endoscopic surveillance of the gastrointestinal tract at age 18 when she found to have multiple colonic tubulovillous adenomas and subsequently had a total proctocolectomy with a J-pouch ileoanal anastomosis. She also had an abdominal wall desmoid tumor that was removed. The patient's first endoscopy was at age 19. The first three endoscopies (age 19, 20, and 21) showed fundic gland polyps in the stomach and tubular adenomas in the small bowel. The patient's most recent endoscopy showed multiple diminutive fundic gland like gastric polyps (figure 1, A) which turned to be tubular adenomas on histology. She also was noted to have duodenal tubular adenomas, figure 1, B. The prevalence of gastric adenomas is estimated to be about 9.2%- 23% in FAP. The risk for gastric cancer in FAP patients is 0.6% and seems to be more common in attenuated FAP than in FAP. Although we do not have a true estimate for the rate of transformation from gastric adenoma to malignancy, endoscopic surveillance is still recommended. Endoscopic surveillances have better metric measures in small bowel tubular adenomas than in gastric adenomas using the Spigelman staging system. This case had gastric and duodenal polyps at a much earlier age (19) than the recommended age of screening endoscopy (25-30). This case reminds us of the importance of surveillance EGDs in FAP patients and taking multiple biopsies from polyps which may look like fundic gland polyps on endoscopic evaluation but may be tubular adenomas on histology.Figure 1Figure 2