A retrospective study has linked use of Intuitive Surgical’s robotic system to improved overall survival in oropharyngeal cancer patients, though it did not have an impact on other cancers studied.
The research, which was published in JAMA Oncology Thursday, found 85% of people who underwent robotic surgery were alive five years later, compared to 80% of people who were treated through conventional procedures for the type of head and neck cancer. Researchers called the findings "hypothesis generating" and not conclusive and urged a randomized controlled clinical trial.
However, the researchers found robotic surgery had no effect on overall survival in patients with cancers of the prostate, endometrium and cervix.
Transoral surgery spares head and neck cancer patients from the trauma and disfigurement associated with undergoing a mandibulotomy. However, line-of-sight issues can hinder surgeons who perform transoral procedures using standard endoscopic tools. Intuitive developed its da Vinci robotic surgery system for use in transoral procedures to counter those problems.
The JAMA study provides some evidence Intuitive may have achieved that goal. The authors caution that, while they controlled for some variables, factors such as a higher rate of private insurance in the transoral robotic surgery (TORS) cohort could have influenced the results, leading them to state the findings should be seen as hypothesis generating, not conclusive.
Yet, in the absence of prospective clinical trials comparing TORS to open surgery, the study still represents one of the more comprehensive assessments of outcomes associated with the approach. Despite the lack of evidence of TORS’ effect on survival, surgeons have adopted the technology.
The researchers identified a sharp increase in the use of transoral robotic surgery in the treatment of early-stage oropharyngeal cancer in the years after TORS gained FDA approval in late 2009. In 2010, surgeons used robots in the 18% of procedures to treat oropharyngeal tumors up to 4cm in size. By 2015, the figure had increased to 36%. The researchers tracked an increase from 6% to 14% in the proportion of facilities that carried out at least one TORS operation over the same period.
Yet, TORS remains a relatively small, slow-growing part of Intuitive’s business. Over the past decade, the number of general surgical procedures performed annually using Intuitive robots has grown from practically zero to almost 500,000. The annual numbers of gynecology and urology procedures has risen from around 100,000 to more than 300,000 over the same period.
Relative to those numbers, TORS has barely grown. At well below 50,000 procedures a year, TORS is by far the smallest of the five robotic surgery applications tracked by Intuitive.
The growth in robotic use in other areas is partly driven by short-term benefits, notably reduced recovery time. Writing in an editorial published alongside the JAMA paper, surgeons at Memorial Sloan Kettering Cancer Center said “rigorous research into long-term survival is sorely needed.”
The JAMA study itself generated evidence to suggest the research may fail to show robotics improves survival in some cancers. The five-year survival figures for robotic and non-robotic prostatectomy and total hysterectomy for endometrial cancer were nearly identical. Five-year survival in patients who underwent robotic total hysterectomy for cervical cancer was numerically slightly worse than in the non-robotic cohort.