Endoscopic Findings in Patients With PTEN Hamartoma Tumor Syndrome Undergoing Surveillance.

Goals And Background: Phosphatase and tensin homolog hamartoma tumor syndrome (PHTS) is an inherited disorder that increases the risk for cancer in multiple organ systems, including breast, endometrial, thyroid, and the gastrointestinal tract. Surveillance is recommended however there lacks data to describe the change in polyposis phenotype and cancer incidence over surveillance. Our aim is to describe the polyposis phenotype and cancer incidence in PHTS patients undergoing endoscopic surveillance.

Study: PHTS patients, ages 17 through 89, who underwent at least 2 esophagogastroduodenoscopy (EGDs) or colonoscopies were identified. Number and sizes of polyps were noted, from which 5 categories were recreated. Incidence of colorectal and gastric cancer was evaluated.

Results: Seventy patients were included. Patients were clustered and classified into 1 of 5 categories: no polyps, few small polyps (<1 cm, < 10 polyps), few large polyps (≥1 cm, < 10 polyps), many small polyps (<1 cm, ≥10 polyps), many large polyps (≥1 cm, ≥10 polyps). There was no significant difference in polyp number or size on EGD (P=0.47 and 0.83, respectively) or colonoscopy (P=0.49 and 0.10, respectively) over the surveillance period (4.8±3.9 y for stomach and 5.6±4.4 y for colon). The average interval between endoscopies was 28±24 months for EGDs and 29±23 months for colonoscopies. A stage II transverse colon adenocarcinoma and stage IV gastric adenocarcinoma were identified. Standardized incidence rates for gastric and colon cancers were 5427 (P=0.0002) and 353 (P=0.002), respectively.

Conclusions: PTHS individuals can be classified into polyposis phenotypes which do not change over an endoscopic surveillance period. Two cancers were associated with a large size polyp phenotype. Surveillance intervals should be determined by polyp size ≥1 cm and pathology.