The agency also called out robotically assisted surgical (RAS) device use in the United States that lacks proper federal oversight.
“The FDA is aware of allegations that clinical studies are being conducted” with RAS devices in breast cancer “without the FDA oversight required for such significant risk studies,” the agency said.
The new advisory comes 4 weeks after a Medscape Medical News exclusive story on a set of clinical trials recently underway using RAS devices for nipple-sparing mastectomy, both prophylactically and as a breast cancer treatment.
The report found that investigators are either not collecting cancer outcomes or not doing so as a primary measure – despite a stiff warning in 2019 from the FDA that those outcomes are important.
“Congratulations to the press on doing its job well and informing government. I think this [safety communication] is a direct result of Medscape following up on this issue,” said Hooman Noorchashm, MD, PhD, a patient advocate from Philadelphia. He is a former surgeon and faculty member at the University of Pennsylvania.
In reviewing the FDA’s new warning, Dr. Noorchashm pointed out that the agency also stated unequivocally – after previously hinting – that any study of robotic mastectomy “must include monitoring of long-term clinical outcomes” such as cancer recurrence, disease-free survival, and overall survival.
That’s a change in approach – previously the FDA has typically approved/cleared RAS devices for use in cancer surgery based on 30-day complication rates (compared with standards of care) and had no requirement for cancer-related outcomes data.
“This [new] advisory reiterates the need for a clear focus on primary oncologic outcomes to, at the very least, demonstrate the noninferiority of robotic assisted surgical devices for performing mastectomy procedures,” said Dr. Noorchashm.
In a 2019 warning about robotic mastectomy, the FDA suggested that it would require oncologic measures moving forward, saying that it “anticipates” that any evaluation of new use of robotic devices in women’s cancer “would be supported” by long-term cancer outcomes. But it stopped short of publicly saying so. The new advisory changes that.
Direct comparison with traditional mastectomy needed
There are safety concerns with robotic mastectomy. Experts question whether a surgeon can easily remove a breast tumor in one piece through the small incision (a selling point of the robot). If the tissue cannot be removed in one piece, cancer fragments may be left behind.
As a result, a randomized trial with traditional open mastectomy as a comparator is needed, Dr. Noorchashm stressed. The current batch of clinical trials in the United States are all single-arm studies and as such are “totally inappropriate,” he said.
Julie Margenthaler, MD, a breast surgeon at Washington University in St Louis, also noted the importance of a randomized trial.
“I feel strongly that robotic-assisted mastectomy should only be performed in the setting of a well-designed clinical trial and that oncologic outcomes should be a primary or secondary endpoint analysis as part of that trial,” she said in an email.
Intuitive Surgical, a California-based manufacturer of robotic devices in health care and a pioneer in robot-assisted surgery, is funding one of the current clinical trials of robotic mastectomy in the United States – a single-arm, five-center trial examining use in the prophylactic setting. The two primary outcomes are conversions to open mastectomy (efficacy measure) and the incidence of adverse events during surgery to 42 days after surgery (safety measure).
This news organization previously asked the company, which manufactures the market leader da Vinci robotic surgical equipment, if it planned to conduct a randomized trial.
“Any plans for use of da Vinci Xi surgical system in nipple-sparing mastectomy will be based on these [single-arm] study results as well as other data and evidence,” said a spokesperson, who did not confirm use of a randomized trial.
The new FDA requirement for long-term oncologic outcomes also in part arises from “diminished long-term survival” that was associated with robotic surgery and other minimally invasive surgery for hysterectomy related to cervical cancer.
A version of this article first appeared on Medscape.com.