Shape-sensing robotic bronchoscopy ‘a promising technology’ for biopsy of pulmonary nodules

Early results from the PRECIsE multicenter study showed shape-sensing robotic-assisted bronchoscopy yielded high sensitivity for malignancy for pulmonary nodules and had a favorable safety profile.

Electromagnetic navigation bronchoscopy for diagnosing pulmonary nodules shows a sensitivity for malignancy of roughly 77%, but there is wide variation in the literature, David E. Ost, MD, MPH, FCCP, professor in the department of pulmonary medicine in the division of internal medicine at the University of Texas MD Anderson Cancer Center, Houston, said during a virtual presentation at the CHEST Annual Meeting.

“There is limited data on shape-sensing robotic-assisted bronchoscopy, and [PRECIsE] is the first large, multicenter, prospective, observational study,” Ost said.

PRECIsE study

PRECIsE is a prospective, observational, multicenter study that evaluated shape-sensing robotic-assisted bronchoscopy with the Ion Endoluminal System (Intuitive Surgical). The cohort included patients with peripheral pulmonary nodules that were 10 mm to 30 mm in diameter, with high suspicion for malignancy.

The platform features an ultra-thin, maneuverable robotic catheter that allow navigation far into the peripheral lung and a peripheral vision probe that permits direct vision while navigating the small and difficult-to-navigate airways. Shape-sensing technology enables active robotic control of the catheter during navigation and the biopsy process, according to the company.

“Importantly, this is a new technology. The doctors doing the study had never used it before. They went through a learning phase,” Ost said.

Eleven physicians at six centers went had a learning of five to 10 cases and continued to build their experience over the next 150 cases.

Ost presented preliminary results from the first 69 patients (median age, 69 years; 58% women) who completed 1 year of follow-up.

Shape-sensing robotic-assisted bronchoscopy resulted in an 83% diagnostic yield, according to a company press release.

Results also showed encouraging diagnostic yield for both smaller and larger nodules: the technology helped physicians obtain a diagnosis in 82% of cases with nodules of 1 to 2 cm and in 85% of cases with nodules between 2 and 3 cm, according to the release.

The researchers reported no serious adverse events in the first 69 patients. There were no incidences of pneumothorax events requiring a chest tube, according to the release.

Sensitivity for malignancy from samples obtained from nodule biopsy was 84% to 88%, according to the release.

These preliminary results in 69 patients are a subset of the PRECIsE study’s total of 365 patients, enrolled beginning in March 2019.

“This is a promising technology for biopsy of peripheral pulmonary nodules, Ost said. “Final data will be submitted once 1-year follow-up is finished for all patients, and we will use the same type of detailed reporting and classification for complete transparency.”

Shape-sensing robotic bronchoscopy with mobile 3D imaging

Another study presented during the session focused on the combination of shape-sensing robotic-assisted bronchoscopy with mobile 3D imaging to verify tool-in-lesion and assess divergence.

“The recent emergence of robotic platforms has shown an increase in diagnostic yield of anywhere from 70% to 90%,” Janani S. Reisenauer, MD, thoracic surgeon at the Mayo Clinic, Rochester, Minnesota, said during the presentation. “However, despite adequate navigation, the management of CT to body divergence remains a problem.”

Reisenauer and colleagues conducted a prospective, single-center, single-arm study to assess the early performance and clinical utility of the Cios 3D Mobile Spin along with the Ion Endoluminal System to identify peripheral pulmonary nodules 1 cm to 3 cm in diameter. In addition, researchers aimed to evaluate CT to body divergence using these tools.

This study included 30 patients (mean age, 69.3 years; 43.3% women) with a moderate to high probability of pulmonary nodule malignancy who could tolerate robotic bronchoscopy with general anesthesia. Researchers defined diagnostic yield by pathology results and tumor board review. CT to body divergence was defined as a greater than 10% overlap or a 10 mm distance between the pre-procedural and the tool-in-lesion targets.

Median nodule size was 17.5 mm, mean airway generation was seven and 40% of patients presented with a positive CT bronchus sign.

The tool-in-lesion rate was 96.7%. There was a mean of 2.5 spins per case. Mean fluoroscopy time was 8.73 minutes. Mean dose area product was 50.3 Gy*/cm², according to the results.

Twenty-two patients had a malignant diagnosis and six had benign specific diagnoses. The combination of shape-sensing robotic-assisted bronchoscopy with mobile 3D imaging resulted in a diagnostic yield of 93%, Reisenauer said.

Divergence was measured by calculating the displacement of the target from the pre-procedure CT and intraoperative CT. In 28 cases with available data, divergence existed 50% to 60% of the time, with a median divergence of 10 mm for an upper lobe nodule and 21 mm for a lower lobe nodule, according to Reisenauer.

No cases of pneumothorax or clinically significant bleeding were reported.

“The combination of mobile 3D imaging with shape-sensing robotic bronchoscopic biopsy of pulmonary nodules is not only safe and feasible, and in conjunction with appropriate anesthetic pathways can overcome nodule motion and divergence in a majority of patients,” Reisenauer said. “Future studies are warranted to develop replicable and reliable mechanisms to quantify and overcome divergence.”

References:

• Ost D, et al. Chest. 2021;doi:10.1016/j.chest.2021.08.034.
• PRECIsE clinical study preliminary results favorable for Intuitive’s Ion Endoluminal System for peripheral nodule lung biopsy. https://isrg.intuitive.com/news-releases/news-release-details/precise-clinical-study-preliminary-results-favorable-intuitives. Published Oct. 18, 2021. Accessed Oct. 18, 2021.
• Reisenauer J, et al. Late Breaking Lung Cancer and Lung Nodule Abstracts. Presented at: CHEST Annual Meeting; Oct. 17-20, 2021 (virtual meeting).
• Reisenauer J, et al. Chest. 2021;doi:10.1016/j.chest.2021.08.032.