The Airway As the First Signal of Relapse: Metachronous Endobronchial Metastasis From Cutaneous Melanoma

Melanoma is a malignant tumour with a recognised potential for late recurrence. Although pulmonary involvement is common in advanced disease, endobronchial metastasis is rare and may present with non-specific respiratory symptoms. We report the case of an 85-year-old woman with a history of stage IIA melanoma of the right thumb treated with amputation in 2014, and no evidence of disease until loss to follow-up in 2022. Nearly ten years after initial treatment, she developed progressive cough, haemoptysis and dyspnoea. Chest CT revealed right lower-lobe atelectasis with post-obstructive changes. Bronchoscopy demonstrated a friable endobronchial lesion obstructing the right B9 segment. Histopathological examination showed spindle-cell malignant melanoma with diffuse Melan-A and vimentin expression and focal S100 positivity, while epithelial markers were negative. Molecular testing confirmed BRAF wild-type status, supporting metastatic recurrence. The patient subsequently developed recurrent haemoptysis and worsening dyspnea requiring hospitalisation. Palliative radiotherapy achieved temporary haemostatic benefit relief. Pembrolizumab was initiated, but disease progression ultimately occurred after several months, accompanied by functional decline. Brain imaging performed after a seizure episode revealed multiple cerebral metastases. She transitioned to best supportive care and died in early 2025. This case highlights a rare metachronous endobronchial recurrence of melanoma occurring a decade after primary tumour resection. Endobronchial metastasis should be considered in patients with a remote history of melanoma presenting with new respiratory symptoms. Prompt diagnosis through bronchoscopy and immunohistochemistry enables timely implementation of palliative and supportive management.