Tracheobronchopathia Osteochondroplastica - to Biopsy or not to Biopsy? A Relook at The Rare Disease.

Background: Tracheobronchopathia osteochondroplastica (TPO) is a rare idiopathic disease involving the tracheobronchial tree. It is mostly an incidental finding with non-specific clinical manifestations. It has typical bronchoscopic, radiological features and biopsy is usually considered non-essential. The study aimed to determine whether biopsy makes a difference in the management of patients.

Methods: All patients diagnosed with TPO in our institution over 15 years (2005 to 2020) were included in this study. Their medical records, chest computed tomography (CT), and bronchoscopy reports were retrospectively reviewed, and data were analysed. All the CT images were reviewed by a senior chest radiologist.

Results: From the 20,000 bronchoscopies and 260,000 CT thorax images obtained, 28 cases were diagnosed as TPO based on either bronchoscopy or radiology or both. Among the 19 cases diagnosed through bronchoscopy, 16 underwent a biopsy. In addition to TPO features, biopsy showed additional diagnoses in 6 cases. In 9 cases, TPO was not initially diagnosed by CT but by bronchoscopy. In 8 patients, TPO was diagnosed incidentally on CT performed for other reasons. On follow-up with the treatment of underlying/co-existing concomitant aetiologies, clinical improvement was noted in all patients. None of them progressed to respiratory failure or airway obstruction until the last follow-up.

Conclusion: Among patients who underwent bronchoscopic biopsy of TPO lesions, 38% had biopsy results showing an alternative aetiology, which led to changes in the treatment plan for all these patients. Hence, a bronchoscopic biopsy of TPO lesions should be performed to rule out other aetiologies.