Balloon Dilatation and Cryobiopsy on an Ultra‐Peripheral Ground Glass Nodule: A Case Report

Ground‐glass nodules (GGNs) pose a considerable diagnostic challenge. Recently, a balloon catheter to dilate peripheral bronchi has become commercially available, offering a potential solution to this limitation. This is a case of a 73‐year‐old female nonsmoker with rheumatoid arthritis on Tacrolimus. Chest CT scan showed a 13.9‐mm pure GGN at the right upper lobe. Annual chest CT scan noted stability in size for 7 years, but recently the size increased to 17.0 mm with a positive bronchus sign in the 12th generation. An ultrathin bronchoscope could be inserted up to the 9th generation. Balloon dilatation was done at this point to pass the subsequent tortuous bifurcation, advancing the bronchoscope further up to the 10th generation. Where radial endobronchial ultrasound showed a blizzard sign, cryobiopsy was performed, revealing lung adenocarcinoma. This case highlights the value of balloon dilatation and cryobiopsy for ultra‐peripheral GGNs.