Experts at the Icahn School of Medicine at Mount Sinai are setting a new benchmark in lung nodule diagnosis by combining robotic bronchoscopy with cryobiopsy. This approach increases diagnostic yield without compromising patient safety.
“Robotic bronchoscopic cryobiopsy has become a routine part of my procedure for lung nodule diagnosis,” says Udit Chaddha, MBBS, Associate Director of Interventional Pulmonology and Director of the Respiratory Institute Pleural Service at the Icahn School of Medicine. “In my experience, it’s a game-changing practice.”
Adding Cryoprobes to Robotic Bronchoscopy
Traditional guided bronchoscopy is invaluable for lung cancer diagnoses but insufficient for reaching certain small lesions and some areas of the lung. As a result, diagnostic yields—the proportion of biopsies that result in a specific diagnosis—tended to hover around 60-70 percent. The introduction of technologies such as robotic bronchoscopy and cone beam CT guidance has improved physicians’ ability to access deeper and more difficult spots in the lungs, increasing diagnostic yield to around 85 percent.
“Still, the biopsy tools we’ve been using once we reach those targets are decades old,” Dr. Chaddha says. “The addition of the cryoprobe enables us to take larger and better-preserved specimens and even sample lesions when the tool is positioned adjacent to them.”
Cryoprobes, which rapidly freeze and collect tissue, are not new. However, only in the last two years have manufacturers produced a cryoprobe small enough for robotic systems. This advance has made a notable difference, Dr. Chaddha says. To date, no large, randomized trials have confirmed the superior yield using this technique, though small studies have reported encouraging results that are congruent with the experience of Dr. Chaddha and his colleagues. “In our experience, robotic bronchoscopic cryobiopsy helps achieve a definitive diagnosis in 90-95 percent of cases,” he says.
A cryoprobe being introduced through robotic bronchoscopy to obtain transbronchial cryobiopsies
A yield of 90-95 percent may be at the upper limits of what is currently possible. Diagnostic yield will likely never reach 100 percent since a small portion of suspicious spots are caused by inflammation or infections that often do not have pathognomonic histopathology.
These yields are likely even superior to the diagnostic capabilities of CT-guided biopsies, in which radiologists access lung lesions using a needle through the chest or back. Such biopsies, however, have up to a 30 percent risk of a pneumothorax, Dr. Chaddha says. “With robotic bronchoscopic cryobiopsy, our local pneumothorax rates are 1 percent or lower,” he adds.
There also seems to be only a negligible risk of bleeding—in fact, Dr. Chaddha has yet to see a significant bleed caused by the procedure. “We can now achieve the higher diagnostic yield with a far better safety profile,” he says.
Beyond Diagnosis: Enabling Precision Oncology
Robotic bronchoscopic cryobiopsy offers another important benefit beyond diagnostic yield. “Today, simply confirming a diagnosis of lung cancer is not enough,” Dr. Chaddha says. A myriad of targeted therapies are available to treat lung cancers, but matching the right treatment to each patient requires comprehensive biomarker testing on biopsy samples. “Anecdotally, cryoprobes appear to give us bigger and better-preserved samples for molecular testing,” he adds.
Large-scale multicenter studies have not yet confirmed this benefit of lung biopsies. However, randomized controlled research has demonstrated the superiority of cryobiopsy in lymph node sampling, and small studies have found lung cryobiopsy yields larger and more diagnostic specimens than forceps biopsy. A robotic bronchoscopic procedure with comprehensive nodule sampling takes less than 20 minutes, and there is no real learning curve for adding the cryoprobe to the standard procedure, Dr. Chaddha says.
Working at a health care system at the forefront of medical innovation, interventional pulmonologists at the Icahn School of Medicine were early adopters, beginning to use robotic bronchoscopy in 2021 and cryobiopsies in 2023. Today, Dr. Chaddha says it has become his go-to tool for all lung and lymph node biopsies.
“This tool, in conjunction with contemporary navigational bronchoscopy and confirmatory imaging technologies, likely increases our diagnostic yield to a number that’s possibly as good as we’re going to get for a very long time. And it does so without any compromise in safety,” he says.
The procedure team includes, from left, pulmonary fellow Tahir Malik, MD, Dr. Chaddha, and interventional pulmonology fellow Kimia Ganjaei, MD.