Transoral Robotic Surgery Shows Promise for Patients with Early-Stage OPSCC

August 27, 2020

Researchers found that transoral robotic surgery “seems safe and effective compared to what’s been the standard of care for many years” for patients with early-stage oropharyngeal squamous cell carcinoma.

A study published in JAMA Oncology suggested that transoral robotic surgery was associated with improved surgical outcomes and survival compared with nonrobotic surgery in patients with early-stage oropharyngeal squamous cell carcinoma (OPSCC).1

However, these results were only hypothesis generating, and further prospective trials would help researchers to better understand the optimal treatment paradigm for early-stage oropharyngeal cancer.

“Our purpose in doing this study was to see how this new technology, which has never been tested in a randomized, controlled trial, has influenced patterns of treatment and outcomes since its FDA approval,” Zachary S. Zumsteg, MD, assistant professor of Radiation Oncology at Cedars-Sinai, said in a press release.2 “There is a learning curve with any new surgical technique, and new ones don’t always translate into equal or improved outcomes.”

Using a retrospective cohort of 9745 patients in the National Cancer Database with clinical T1 and T2 oropharyngeal squamous cell carcinoma diagnosed between January 1, 2010 and December 31, 2015 who underwent definitive robotic and nonrobotic surgery, researchers performed a comparative effectiveness analysis. Survival after robotic and nonrobotic surgery was also compared in 3 unrelated cancers, including prostate, endometrial, and cervical cancer.

Of the total cohort, 2695 patients underwent transoral robotic surgery. Notably, following the approval of transoral robotic surgery for early-stage oropharyngeal cancer by the FDA in 2009, from 2010 to 2015 there was a significant increase in the use of robotic surgery from 18.3% to 35.5% of all surgical procedures for T1 and T2 oropharyngeal cancers (P = .003).

Overall, robotic surgery was found to be associated with lower rates of positive surgical margins (12.5% vs 20.3%; P < .001) and lower use of adjuvant chemoradiotherapy (28.6% vs 35.7%; P < .001). Among 4071 patients with known HPV status, robotic surgery was associated with improved overall survival (OS) compared with nonrobotic surgery in multivariable Cox proportional hazards regression (HR, 0.74; 95% CI, 0.61-0.90; P = .002). Moreover, similar results were observed when analyzing only the subset of facilities offering both robotic and nonrobotic surgery.

“At a minimum, robotic surgery for oropharyngeal cancer patients seems safe and effective compared to what’s been the standard of care for many years,” Zumsteg said.

In propensity score-matched cohorts, the 5-year OS was 84.8% vs 80.3% among patients undergoing robotic vs nonrobotic surgery (P = .001). Contrastingly, there was no evidence that robotic surgery was associated with improved survival in prostate cancer (HR, 0.92; 95% CI, 0.79-1.07; P = .26), endometrial cancer (HR, 0.97; 95% CI, 0.90-1.04; P = .36), or cervical cancer (HR, 1.27; 95% CI, 0.96-1.69; P = .10).

“Overall, we did not find evidence that systematic survival differences in robotic vs nonrobotic surgery are present in national registry data,” the authors explained. “The association of robotic surgery with improved survival appears to be unique to OPSCC.”

Importantly, it is currently unclear how transoral robotic surgery-based treatment paradigms compare with definitive radiotherapy-based approaches in terms of cancer control, toxic effects, or quality of life. The phase 2 randomized ORATOR trial recently demonstrated similar oncologic outcomes, but worse swallowing function in patients with early-stage OPSCC who were treated with transoral robotic surgery compared with definitive radiotherapy, though the difference did not meet statistical significance.

Given this observation, the researchers suggested that it is possible that toxicity with transoral robotic surgery-based approaches would be more favorable if transoral robotic surgery enabled deintensification of postoperative therapy. Of note, several phase 2 trials have already shown promising results with this ideal, and phase 3 trials are ongoing.

References:

1. Nguyen AT, Luu M, Mallen-St Clair J, et al. Comparison of Survival After Transoral Robotic Surgery vs Nonrobotic Surgery in Patients With Early-Stage Oropharyngeal Squamous Cell Carcinoma. JAMA Oncology. doi: 10.1001/jamaoncol.2020.3172.

2. Robotic Surgery May Improve Outcomes in Mouth and Throat Cancer [news release]. Los Angeles. Published August 20, 2020. Accessed August 21, 2020. https://www.newswise.com/articles/robotic-surgery-may-improve-outcomes-in-mouth-and-throat-cancer?sc=dwhr&xy=10019792