Tumour Seeding After Transbronchial Cryobiopsy in a Patient With Newly Diagnosed Lung Cancer.

Tumour seeding following biopsy is a rare but clinically significant complication in lung cancer diagnostics, particularly in aggressive malignancies. A 66-year-old male with a significant smoking history and known chronic obstructive pulmonary disease presented with chronic cough and weight loss. Imaging revealed a central airway mass with mediastinal lymphadenopathy. Bronchoscopic evaluation and biopsy confirmed the diagnosis of metastatic non-small cell lung cancer with high PD-L1 expression. Shortly after the initial procedure, the patient developed airway obstruction due to a rapidly growing endobronchial lesion at the prior biopsy site, confirmed histologically as tumour seeding. Multiple bronchoscopic interventions were required to restore airway patency. Despite prompt escalation to combined chemo-immunotherapy and repeated multimodal airway recanalisation, the disease demonstrated aggressive local recurrence. This case highlights the potential for endobronchial tumour seeding following diagnostic interventions in lung cancer, underscoring the importance of vigilant follow-up and prompt management in cases with rapid disease progression.