MMC injections may end cycle of contracture Tx failures

Burlington, MA-In patients with recurrent bladder neck contractures, history often repeats itself with multiple surgeries and poor outcomes, but reconstructive urologists are now hopeful they have a better solution.

In a retrospective study, surgeons from the Lahey Clinic in Burlington, MA, reported that a novel approach using radial urethrotomy with mitomycin C (MMC) injections led to a patent bladder neck in nearly three-fourths of patients after a single procedure and 81% after two procedures.

“For patients who have failed standard management of these challenging recurrent bladder neck contractures, they should be given the opportunity for this adjunctive agent to improve their outcome and need no further intervention,” study co-author Jill C. Buckley, MD, told Urology Times.

“Otherwise, we would be just continuing to do what had been done-more incisions, more dilations, more Foley-dependent patients,” said Dr. Buckley, a former Lahey Clinic faculty member who is currently associate professor of urology at the University of California, San Diego Health System.

The study, presented at the AUA annual meeting in Orlando, FL, is a follow-up to an initial pilot study by the Lahey group published 3 years ago in the Journal of Urology (2011; 186:156-60). AUA attendees urged the researchers to conduct a prospective, randomized study and raised concerns about possible adverse events.

Next: Multiple previous procedures

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Multiple previous procedures

The current study was designed to examine the long-term safety and efficacy of radial urethrotomy plus MMC in patients with recurrent bladder neck contractures.

A total of 37 patients were included, with a mean age of 64 years and a median contracture size of 10F. All patients had at least one prior failed direct vision internal urethrotomy (DVIU) or dilation. One-fourth of patients previously had two traditional endoscopic procedures, which included DVIU, dilation, or both; 16% had more than two procedures; one-third had indwelling catheters; and one-fourth were on a dilation schedule.

Most of the contractures occurred following radical prostatectomy.

The surgical technique typically involves three to four incisions at the 10, 2, 4, and 8 o’clock positions. Using a 21F scope, surgeons inject .3 to .4 mg per cc of MMC at these sites, and the bladder neck is subsequently calibrated to >26F.

Success was defined as a stable bladder neck >16F without the need for dilation or catheterization confirmed by passing a flexible cystoscope at 3, 6, 9, and 12 months. Results of the current study confirmed those of the original pilot study.

Next: 70% of patients show stable bladder neck after 1 procedure

“At a mean follow-up of 2 years, 70% of these patients had a stable bladder neck after one procedure. It increased to 81% after two procedures,” said Kamal Nagpal, MD, a Lahey Clinic resident who presented the findings in Orlando.

Fourteen percent of patients required more than two procedures to maintain a stable bladder neck, and the failure rate was 5% (two patients). One-fifth of patients were incontinent after their procedure, and eight patients received an artificial urinary sphincter.

“To conclude, radial urethrotomy with mitomycin C is a safe, effective, and minimally invasive approach for these patients,” Dr. Nagpal said. “However, we need randomized studies with blinding and longer follow-up to confirm these results.”

Saline-controlled study needed

Audience member Allen F. Morey, MD, called the procedure a “very novel, interesting approach.” But he questioned whether the outcomes were attributable to the mitomycin C or the depth of the transurethral incisions, citing his own group’s study showing similar results in a similar patient series without the use of MMC (Urology 2013; 82:1430–5).

“I would implore you to do a randomized, saline-controlled study,” said Dr. Morey, professor of urology at the University of Texas Southwestern in Dallas.

“I am looking to attempt to get a blinded, randomized, controlled trial started to answer this question,” Dr. Buckley said. “Funding is the issue. A recent study out of Michigan analyzed bladder neck incision alone versus bladder neck incision with MMC injection, showing a significant benefit to the adjunctive use of MMC. We are awaiting final publication.”

Jeremy Myers, MD, assistant professor of surgery (urology) at the University of Utah, Salt Lake City, said a retrospective review of the procedure at several U.S. institutions uncovered three serious adverse events among 66 patients undergoing mitomycin C injections in conjunction with bladder neck incisions. Two patients required cystectomy as a result of complications, he said.

Dr. Buckley noted that her group uses MMC judiciously, adhering to a concentration dose that’s well described in the literature, and is careful not to over instill the medication in one setting.

“We have not experienced local wound breakdown, ulceration, or delayed healing and believe this is due to a strict adherence to our predetermined incision and dosage technique,” she said. “It is a powerful agent that we know can be effective, but increasing the dose or amount delivered also increases the risk of toxicity and thus the potential for short- or long-term complications.”UT 

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