Results of pathologic analysis of buccal mucosa used in first- and second-stage adult urethroplasty procedures shows it is a robust tissue for grafting.
Houston-Results of pathologic analysis of buccal mucosa used in first- and second-stage adult urethroplasty procedures shows it is a robust tissue for grafting.
The epithelium also appears to be resistant to developing changes of lichen sclerosis, say researchers from the University of Texas Health Sciences Center, Houston, and the University of Washington, Seattle.
"When used as graft tissue in two-stage urethroplasty, buccal mucosa appears to maintain its squamous epithelial histologic anatomy despite the change from a moist to dry environment," said first author Thomas G. Smith III, MD, assistant professor of urology at the University of Texas Health Sciences Center.
Urethral or reconstructive urethral plate biopsy was performed in 30 patients, and harvested buccal mucosa was biopsied in 21 of those patients. The first stage failed in five patients, but the remaining 25 patients went on to second-stage urethroplasty after a mean of 13.3 months, and all 25 had biopsy of the harvested buccal mucosal graft bed.
Lichen sclerosis was diagnosed in seven men based on histologic analysis of the initial urethral pathology, and the pathology showed chronic inflammation consistent with lichen sclerosis in another six men. In addition, the biopsies showed fibrosis or nonkeratinized squamous tissue in five men each, keratinized squamous skin in four men, and normal urethra in two. The analysis of the buccal mucosa at harvest showed normal tissue in 17, chronic inflammation in two, and minor histologic variant in two.
Of the five men who did not go on to the second-stage urethroplasty, two had failure secondary to recurrent lichen sclerosis, one failed secondary to graft fibrosis, and two elected not to proceed with further surgery.
No graft-related failure seen
"In no patient in this series was failure due to pathology noted on the initial buccal mucosa graft," said Dr. Smith, who presented the study at the 2010 AUA annual meeting in San Francisco.
Histologic evaluation of the buccal mucosal graft bed harvested at the second-stage procedure showed normal squamous epithelium in 15 men and mild chronic inflammation with normal epithelium in four men. However, pathologic changes were found in six men, including two each with fibrosis, chronic inflammation, and lichen sclerosis.
"Overall, four of 11 men with lichen sclerosis or chronic inflammation who went on to the second stage showed evidence of recurrence in the graft," Dr. Smith noted.
Retrograde urethrogram results showed urethral patency was achieved in 23 of the 25 patients who underwent second-stage urethroplasty. In one of the failures, the buccal mucosal graft showed recurrent lichen sclerosis, while the other showed chronic inflammation that would be consistent with lichen sclerosis.
"However, in two other men the urethra was patent despite a pathologic diagnosis of or consistent with lichen sclerosis," Dr. Smith said.