Outcomes of atypical pathologic changes following robotic-assisted bronchoscopy

SESSION TITLE: Robotic Revolution: The Changing Landscape of Bronchoscopy SESSION TYPE: Original Investigations PRESENTED ON: 10/10/2023 01:45 pm - 02:45 pm PURPOSE: Robotic assistant bronchoscopy (RAB) is an emerging technology with potential to increase the diagnostic yield of peripheral nodule sampling. Currently, there are few studies reporting on diagnostic yield of RAB, limited by small sample size and varying definitions, with no standardized approach to the measurement of diagnostic yield. A pathologic finding of atypia remains a controversial diagnostic category and there is limited data reporting pathologic follow up and outcomes in this subset population. Here, we aim to quantify the diagnostic yield using a strict definition, analyze the impact of atypia on diagnostic yield, and report the patient’s ultimate pathologic diagnosis or treatment pathway. METHODS: Consecutive patients who underwent RAB at a single center from November 2020-January 2022 were included in this retrospective analysis. Patient demographics, nodule characteristics, and pathology reports were extracted. All cases were performed using RAB (Ion, Intuitive Surgical, CA, USA) and were collected either via fine needle aspiration, transbronchial forceps biopsy, or both. Samples were considered diagnostic if there was confirmed malignancy or a definitive benign finding (atypia and non-specific benign findings were considered non-diagnostic). To assess the impact of atypia on diagnostic yield and risk of misclassification of atypia as a true positive, outcomes were further stratified into two definitions. The first as previously described excluded atypia (strict definition) and second included atypia (liberal definition). In cases of pathologic atypia with RAB, 1 year follow-up data was extracted. The primary endpoint was the proportion of patients with atypia that ultimately were diagnosed or treated for malignancy. RESULTS: 156 participants at a single center were included, with a mean age of 67+/-9 years. Mean nodule size was 21+/-11mm, mean distance to pleura was 35+/-22 mm with 34% of the nodules in the outer third of the lung, and 31% had a positive bronchus sign. Using a strict definition (atypia as non-diagnostic), the overall diagnostic yield of RAB was (76/156) 49%. Under the liberal definition (atypia as diagnostic), the diagnostic yield was 97/156 (62%), with 61/156 (39%) malignant, 15/156 (10%) benign, and 21/156 (13%) of cases with atypia. At 1 year follow-up of atypia cases, 8/21 underwent repeat biopsy, all (8/8) confirmed malignancy, 10/21 were presumed malignant by their oncologist and underwent treatment, and only 3/21 underwent surveillance with stable imaging. Overall, 18/21 (86%) of atypia cases were ultimately diagnosed and/or treated for malignancy. Using the liberal definition of diagnostic yield, only 3/156 (2%) patients would be misclassified as a true positive. CONCLUSIONS: The vast majority of cases with atypical pathologic changes following RAB were found to be positive for malignancy. Incorporation of atypia into the definition of diagnostic yield increases yield from 49% to 62%, while misclassifying atypia as a true positive in 2% of cases. CLINICAL IMPLICATIONS: RAB findings of atypia has potential to shift estimates of diagnostic yield and may represent an actionable diagnosis. Prospective assessment with pathologic adjudication is needed to further understand the consequences of classifying atypia as an actionable diagnosis before consideration of classifying atypia as a diagnostic finding. DISCLOSURES: Consultant relationship with Biodesix Please note: 2018-present by A. Christine Argento, value=Honoraria Consultant relationship with Cook Medical Please note: 2019-present by A. Christine Argento, value=Honoraria Consultant relationship with Intuitive Please note: 2019-present by A. Christine Argento, value=Honoraria Consultant relationship with PulmonX Please note: 2019-present by A. Christine Argento, value=Honoraria Consultant relationship with Boston Scientific Please note: 2021- present by A. Christine Argento, value=Honoraria No relevant relationships by Travis Ferguson No relevant relationships by Harold Ibanez Consultant relationship with Veracyte Please note: $1001 - $5000 by Hans Lee, value=Honoraria Removed 03/31/2023 by Hans Lee, source=Web Response Consultant relationship with Olympus Please note: 2021- present by Hans Lee, value=Honoraria No relevant relationships by Deborah Mi No relevant relationships by Cheryl Pai No relevant relationships by Krystle Pew No relevant relationships by Marcelina Puc No relevant relationships by Jeffrey Thiboutot Consultant relationship with Olympus Please note: 2021-present by Lonny Yarmus, value=Grant/Research Support