Rates of minimally invasive surgery for early-stage endometrial cancer may be higher than previously reported, results of a registry study suggest.

Of 3,730 women with endometrial cancer in the Society of Gynecologic Oncology Clinical Outcomes Registry (SGO-COR), 88.8% underwent minimally invasive procedures, reported Amanda Nickles Fader, MD, of Johns Hopkins Hospital, Baltimore, and colleagues.

“When you have surgery with a gyn-oncologist who is specially trained in this type of surgery, we see that women have a very high likelihood of having the appropriate surgery, the minimally invasive surgery, and we thought that this benchmark of an 80% rate of minimally invasive surgery in these patients is very feasible and should be recognized as the standard of care,” Dr. Nickles Fader said in an interview.

Coinvestigator Summer B. Dewdney, MD, of Rush University Medical Center, Chicago, who was instrumental in creating and running the SGO-COR registry, said these findings are encouraging.

“We’re happy to see that rate. It’s the rate that it should be because minimally invasive surgery is the standard of care for endometrial cancer,” Dr. Dewdney said. She added, however, that data supplied to the registry come from gynecologic oncologists who are highly motivated to participate and follow best practice guidelines, which could skew the results slightly toward more favorable outcomes.

Results of the registry-based study are detailed in an abstract that was slated for presentation at the Society of Gynecologic Oncology’s Annual Meeting on Women’s Cancer. The meeting was canceled because of the COVID-19 pandemic.

Assessing adherence to guidelines

In 2015, the SGO Clinical Practice Committee and the American College of Obstetricians and Gynecologists issued a practice bulletin, which stated that “minimally invasive surgery should be embraced as the standard surgical approach for comprehensive surgical staging in women with endometrial cancer.”

Similarly, National Comprehensive Cancer Network guidelines for uterine cancer state that “minimally invasive surgery is the preferred approach when technically feasible” for treatment of endometrial cancer confined to the uterus.

Despite these recommendations, the overall rate of minimally invasive endometrial cancer surgery in the United States is reported be around to 60%, Dr. Nickles Fader and colleagues wrote.

With this in mind, the investigators set out to determine the rate of minimally invasive surgery in women with apparent stage I, II, or III endometrial cancer who underwent hysterectomy with or without staging from 2012 to 2017 at a center reporting to SGO-COR.

The team identified 3,730 women treated at 25 SGO-COR centers; 12 of which were university-affiliated centers and 13 of which were nonuniversity based. Most patients (83.2%) had stage I disease, 4.7% had stage II cancer, and 12.1% had stage III disease. The median patient age was 57 years. Most patients (88%) were white, and two-thirds (67.1%) were obese. In all, 80.4% of samples had endometrioid histology, and 77.7% were either grade 1 or 2.

Factors associated with minimally invasive surgery

The data showed that 88.8% of patients underwent a minimally invasive hysterectomy, composed of robotic-assisted procedures in 73.9% of cases, laparoscopy in 13.4%, and vaginal access in 1.6%.

The proportion of patients who underwent a minimally invasive procedure was significantly higher at nonuniversity centers, compared with academic centers (92.6% vs. 82.7%; P < .0001), but rates of minimally invasive procedures did not differ significantly across U.S. geographic regions.

Dr. Dewdney said that the higher proportion of open surgeries performed at university centers may be attributable to those centers treating patients with more advanced disease or rare aggressive cancers that may not be amenable to a minimally invasive approach.

In a multivariate analysis, factors associated with a failure to perform minimally invasive surgery were black race of the patient (adjusted odds ratio, 0.57), body mass index over 35 kg/m2 (aOR, 1.40), stage II disease (aOR, 0.49), stage III disease (aOR, 0.36), carcinosarcoma/leiomyosarcoma (aOR, 0.58), and university hospital (aOR, 3.46).

Looking at perioperative complications, the investigators found that laparotomy was associated with more in-hospital complications than minimally invasive procedures, including more unscheduled ICU stays (P < .001) and prolonged hospital stays (P = .0002).

Dr. Dewdney said that investigators are planning further registry-based studies focusing on ovarian cancer, uterine cancer, and cervical cancer.

Dr. Nickles Fader and Dr. Dewdney reported having no relevant conflicts of interest.

SOURCE: Nickles Fader A et al. SGO 2020, Abstract 63.