Safety of ablation under question

OB/GYN News, Nov 15, 2001 by Betsy Bates

ASHLAND, ORE. -- Complications arising months to years after total or global rollerball endometrial ablation raise serious questions about the technique's long-term safety, including the "scary" possibility that women who have undergone the procedure may be vulnerable to asymptomatic endometrial cancer, according to Dr. Arthur M. McCausland of Sacramento.

Of 50 patients followed for 10 years after total rollerball endometrial ablation, 2 developed symptomatic cornual hematometras and 3 developed postablation tubal sterilization syndrome (PATSS), he said at the annual meeting of the Pacific Coast Obstetrical and Gynecological Society.

"At first, the technique seemed very safe. But as time passed, certain unique complications became evident," he said of total or global rollerball endometrial ablation, first performed in the late 1980s.

The rollerball technique removes the endometrium, exposing myometrium in much the same way that is seen with newer endometrial ablation techniques. The intrauterine cavity is then surrounded by raw myometrium.

"When you let your distention medium out, these [myometrium-lined intrauterine] walls collapse on each other and have a natural tendency to grow together, peripherally at first," he said. Eventually, the intrauterine cavity is reduced to a narrow, fibrotic tubular structure.

To demonstrate, he showed a slide depicting hysteroscopy results of a patient 1 year after total ablation. The intrauterine walls had grown together, obstructing the cornua. Unfortunately endometrial tissue persists in the cornua or fundus in as many as 95% of cases, according to MRI studies cited by Dr. McCausland.

"If any of these cells decide to turn to cancer, there could be obstructed bleeding and a delay in the diagnosis." Endometrial cancer is the most common gynecologic cancer, but it is usually diagnosed at a curable stage because of postmenopausal bleeding. Without that signal, he said, "I'm afraid the death rate could increase."

Dr. McCausland's presentation documented another set of complications of post--total ablation intrauterine contracture, including bleeding in the cornual area, causing cornual hematometra. In his patients, this complication occurred 37 years after endometrial ablation.

In three patients with previous tubal ligations, the same problem caused retrograde bleeding into the proximal tubal segment 7-44 months after ablation. Patients presented with abdominal pain.

Ultrasound can sometimes be used for diagnosis if a cornual hematometra is large enough, Dr. McCausland said, "but usually you're going to need an MRI."

Both radiologists and pathologists need to be educated ahead of time about cornual hematometras and PATSS or they might miss them, he pointed out.

For example, he showed a hysterectomy specimen that showed only subtle gross changes in a patient diagnosed with PATSS. Only when the specimen was serially sectioned at the proximal tubal segment and cornu did "dark blood come squirting out."

Treatment is not straightforward as it would be for a central hematometra secondary to cervical stenosis, which is easily corrected by dilating the cervix.

In these cases, the uterine wall that has grown together is much tougher to penetrate than adhesions, risking uterine perforation during attempts to break through it.

"If you do drain it, the tract usually doses and ends up recurring," he said.

In that case, patients generally require a hysterectomy.

A possible preventive approach is to ablate only one wall, leaving normal endometrium on the opposite wall and avoiding the cornua and tubal ostia. This "partial ablation" does not cause intrauterine scarring or contracture. This will produce hypomenorrhea, which may not satisfy every patient but will avoid complications such as those Dr. McGausland described.

He was asked whether newer techniques such as balloon ablation would have the same risk of complications.

"I can guarantee you, if you destroy the endometrium and expose myometrium, you will get intrauterine contracture. To me, that can obstruct the cornua.

"I have done balloon ablations in the past and I always have looked up immediately afterward with my hysteroscope and have found good central destruction of the endometrium; however, there was a viable, abundant tissue in both cornua in every patient." When considering the 15%-20% long-term amenorrhea rate after balloon ablation, he said that he wonders, "Where is the cornual bleeding going? It is not going through the cervix."