Anal and perianal reconstruction after extramammary Paget's disease using a posterior thigh flap with a thin square wing.

Extramammary Paget's disease regularly requires a wide resection of skin, often including the anal tract. When reconstructing the anal tract, simulating natural anatomy by creating the thinnest possible flap is essential to prevent incontinence. We reconstructed the anal and perianal area using a posterior thigh trilobed flap. The lobe to be transposed to the anal duct had a square design and was thinned. The other lobes were used to cover perianal defects and the flap donor site. Using this method, we reconstructed three patients who required large perianal area and anal tract resections. All flaps took well, and after the initial healing process, the patients did not develop lasting incontinence. We conclude that the posterior thigh flap with a thin square wing is useful for reconstruction of the anal tract and perianal area.