Pouch cancer in familial adenomatous polyposis. Incidence, risk factors and literature review: a propos of three rare cases

Background:

Development of pouch cancer is a great challenge to both surgeons and patients with familial adenomatous polyposis (FAP) after restorative proctocolectomy (RPC).

Aims:

We aimed to present our experience with pouch cancer diagnosis and review literature data regarding incidence and associated risk factors.

Methods:

This retrospective study enrolled FAP patients undergoing RPC between 1981 and 2023 in our academic institution. It included only J-pouch stapled patients with at least three years of follow-up. Patients’ demographics and disease features were retrieved.

Results:

After excluding seven patients, we selected 87 RPC, and three cases (3.4%) of pouch cancer were identified. They were diagnosed in three men aged 23–40 years at RPC and 41–62 years at cancer diagnosis. Interval from RPC to pouch cancer diagnosis varied from 11.6 to 20 years (average 14.6 years). All patients had colorectal cancers (CRC) detected in the specimen from the index surgery, two of them with multicenter lesions. A brief review of the literature series showed that pouch cancer has been detected in incidences ranging from 0.8 to 3.4%. Male sex, CRC in the RPC specimen, pouch phenotype during follow-up and an association with duodenal adenomas are considered risk factors.

Conclusions:

Pouch cancer is a rare event associated with specific risk factors. After RPC, all patients should undergo endoscopic surveillance, with special attention to those who develop an aggressive phenotype during the first decade of follow-up.