News
An estimated 1 in 370 women who undergo electric power morcellation during a minimally invasive hysterectomy have uterine cancer, with the risk of cancer and endometrial hyperplasia markedly increasing with age, according to an analysis using an insurance database of more than 500 U.S. hospitals.
Dr. Jason Wright
The estimate, published online in JAMA on July 22, is close to the Food and Drug Administration’s estimate that about 1 in 350 women undergoing hysterectomy or myomectomy for presumed fibroids have an unsuspected uterine sarcoma and is higher than historical estimates provided in the literature. The FDA’s estimate, first reported when the agency issued a safety communication in April discouraging the use of laparoscopic power morcellators (LPMs) during a hysterectomy or myomectomy because of the risk of disseminating cancerous tissue and upstaging disease, was based on 9 U.S. and international studies of women treated from 1983 to 2011. The risk of an unsuspected leiomyosarcoma was about 1 in 500.
But unlike the FDA analysis, the most recent analysis, conducted by Dr. Jason Wright and his associates at Columbia University, New York, specifically addressed the risk associated with morcellation. The estimate was based on the records of 232,882 women who underwent a minimally invasive hysterectomy from 2006 to 2012 obtained from a database that represents about 15% of U.S. hospitalizations. Morcellators were used in almost 16% (36,470) of the women, and there were 99 cases of uterine cancers, for a prevalence of 27/10,000 – about one in 370.
Among the women who underwent morcellation, the strongest risk factor for abnormal pathology, either for cancer or any of the precancerous changes, was advanced age. Compared with women under age 40 years, the prevalence ratio for uterine malignancy was 1.42 among those aged 40-44 and 2.55 for those aged 45-49, increasing to 4.97 among those aged 50-54 years, 19.37 among those aged 55-59 years, 21.36 among those aged 60-64 years – and 35.97 among those aged 65 and older.
The researchers also identified cases of endometrial hyperplasia, other gynecologic cancers, and smooth muscle tumors of uncertain malignant potential. The risk of endometrial hyperplasia also increased significantly with age, compared with women under age 40, with prevalence ratios of 1.17 among those aged 40-44 (not statistically significant) and 1.71 among those aged 45-49, to 4.07 among those aged 50-54 years, to 10.21 among those aged 65 years and older. The results are reported in a research letter (doi:10.1001/jama.2014.9005)
Despite the availability of power morcellators for 20 years, "few studies have described the prevalence of unexpected pathology at the time of hysterectomy," Dr. Wright and his associates wrote. While the analysis had limitations, including the lack of long-term follow-up and not being able to verify the pathology results, they concluded that patients who may be undergoing morcellation "should be adequately counseled about the prevalence of cancerous and precancerous conditions prior to undergoing the procedure."
Dr. Charles E. Miller
One of the strengths and unique aspects of this study was being able to identify a large population of women who specifically had morcellation and a hysterectomy, providing a population-based estimate of the prevalence of cancer in this group, Dr. Wright said in an interview. This is slightly different than other estimates and studies, which were not specific to morcellation, including those that looked at the incidence of sarcoma among women who had a hysterectomy. "We could not separate out epithelial endometrial cancers from uterine sarcomas, so this is an estimate of any malignancy within the uterus," so "probably a high proportion of women who underwent morcellation underwent the procedure for fibroid uterus, so the chance of sarcomas is probably higher in these patients than in the general population."
The study did not allow evaluation of whether the use of morcellation increased the risk of dissemination of cancer, which "certainly warrants further study," added Dr. Wright, chief of the division of gynecologic oncology at Columbia.
The lack of data has been one of the major problems surrounding morcellation, with very few studies specifically looking at data that can be used to help guide patients and clinicians. Dr. Wright and his associates hope that their results can help guide patients and clinicians.
"There’s undoubtedly a risk of cancer and precancerous changes in women who undergo morcellation ... and [patients and clinicians] need to weigh that risk," he said. "But certainly morcellation may allow some women to undergo a minimally invasive surgery who otherwise require laparotomy, and the complications and recovery are much easier with minimally invasive surgery, when it’s feasible."
