For early uterine, colorectal and gastric cancer, minimally invasive and open surgeries have been shown to produce similar survival rates. Results of a new cohort study suggest that the same may not be the case for early cervical cancer.
Published in The New England Journal of Medicine, the analysis involved a cohort of more than 2,000 women who underwent radical hysterectomy at Commission on Cancer-accredited hospitals in the United States. The procedures were done between 2010 and 2013 for stage IA2 or IB1 cervical cancer. Of the surgeries, 49.8% were minimally invasive and 50.2% were open.
The research was designed to determine how minimally invasive surgery affected all-cause mortality in women undergoing radical hysterectomy for cervical cancer. The patients had undergone different procedures but were similar with respect to other measured characteristics. Using the Surveillance, Epidemiology, and End Results program database, an interrupted time-series analysis also was conducted involving women who underwent radical hysterectomy for cervical cancer between 2000 and 2010.
Over a median follow-up of 45 months, 4-year mortality was higher in the women who had minimally invasive surgery than in those who had open surgery (9.1% vs 5.3%; hazard ratio, 1.65; 95% confidence interval [CI] 1.22 to 2.22; P = 0.002 by the log-rank test). Women who had the minimally invasive procedures were more likely to be white, privately insured and from ZIP codes with higher socioeconomic status. They were also more likely to have had the surgery in the Northeast and South and at nonacademic facilities. Their tumors tended to be smaller and lower-grade and to have been diagnosed later in the study period than the ones in the women who had open procedures.
Of the minimally invasive surgeries performed on the cohort, 79.8% were robot-assisted laparoscopy. However, use of the device did not change the association between all-cause mortality and route of hysterectomy for early-stage cervical cancer. The authors hypothesized that patient selection or confounding may have contributed to the survival results. They noted that their results differed from previous reports but said the study was larger and had longer follow-up than the earlier trials.
The fact that they could not explain why minimally invasive surgery was associated with shorter survival, the researchers said, was an important limitation. They speculated that the extent of resection may be inherently limited in a minimally invasive procedure or that uterine manipulators may disseminate tumor cells. Surgeon experience also may have played a role if the surgeons who did the open procedures in the women in the cohort were more experienced than were the ones who did the minimally invasive procedures.
The authors noted that adoption of minimally invasive surgery coincided with a decline in the 4-year relative survival rate of 0.8% (95% CI, 0.3 to 1.4) per year after 2006 (P = 0.01 for change of trend). In contrast, from 2000 to 2006, the 4-year relative survival rate for women who underwent radical hysterectomy for cervical cancer was stable.