Background: Diagnosis of ground-glass nodules (GGNs) is challenging. Pure GGNs and subsolid nodules (SSNs) with a solid component less than 0.6cm usually indicate carcinoma in-situ, whereas a solid component larger than 0.6cm indicates invasive carcinoma. Diagnostic yield for GGNs and SSNs with electromagnetic navigation robotic-assisted bronchoscopy was reported at 70.6%.

Aims: Assess diagnostic yield for GGNs and SSNs with solid component less than 0.6cm using shape-sensing robotic-assisted bronchoscopy (ssRAB).

Methods: Retrospective study of patients who underwent ssRAB for evaluation GGNs, from September 2021 to January 2023. Primary outcome was diagnostic yield of ssRAB for GGNs and SSNs with solid component less than 06.cm, secondary outcomes were sensitivity for malignancy, diagnostic yield by type of biopsy tool, and complications that required intervention.

Results: 20 nodules were biopsied from 19 patients. Mean age was 69 years (SD±13.1), 74% were female and 37% had a previous history of cancer. Mean lesion size was 1.80 x 1.27cm (SD± 0.55;± 0.33). Ten nodules were pure GGNs, and ten nodules were SSNs. Mean maximum size for the solid component in SSNs nodules was 0.5cm (SD± 0.06). Overall diagnostic yield was 85%, with a sensitivity for malignancy of 87.5%. Transbronchial needle was diagnostic in 17/20 (85%) cases, 1.1mm cryoprobe was diagnostic in 5/6 (83%) cases, and forceps was diagnostic in 1/3 (33%) cases. Adenocarcinoma was the most common malignancy diagnosed (70%). One procedure-related pneumothorax was reported, not requiring chest tube.

Conclusion: The use of ssRAB shows a high diagnostic yield for diagnosing GGNs and SSNs with a low risk for complications.