Perianal Paget's-an aggressive disease.

Aim: Perianal Paget's disease (PAPD) is a rare disorder with a predisposition to anal and colorectal malignancies and an unclear prognosis. Our previous 25-year series demonstrated a non-aggressive nature. This study aims to describe our updated institutional experience.

Methods: This is a retrospective review of all patients diagnosed with primary PAPD from 1991 to 2021. A prospectively maintained institutional database was searched which included demographics, clinical and pathological manifestations, treatment methods, recurrence, oncological outcome and mortality.

Results: Thirty patients were diagnosed with PAPD. Fifteen were women (50%); the average age at diagnosis was 71 ± 10.7 years, and the average lesion size was 3.7 ± 2.6 cm. At diagnosis, 12 (40%) were harbouring invasive anal adenocarcinoma. Eight (27%) developed adenocarcinomas concurrent with PAPD recurrence at a mean interval of 9 ± 4.4 years (range 1.9-14.8). The Kaplan-Meier curve estimated overall survival of 93%, 86%, 82%, 65% and 56% at 1, 3, 5, 10 and 15 years, respectively. Median survival was 16 years. Six (20%) had disease-related mortality. Initially, nine (30%) were treated with abdominoperineal resection (APR), 15 (50%) underwent local resection, three (10%) were treated with radiotherapy, two (7%) received only topical therapy and one (3%) chose observation. Fifteen (50%) experienced recurrence of PAPD, two after undergoing APR. Five (17%) had persistent disease until death. Only 10 (33%) did not experience PAPD recurrence, seven of whom underwent APR. The mean follow-up time was 9.2 ± 6.2 years.

Conclusions: Perianal Paget's disease is an aggressive entity with high rates of synchronous anal adenocarcinoma at diagnosis and development of metachronous adenocarcinoma later in life.