A case of metastatic endobronchial melanoma from an unknown primary site

Melanoma can occur as a metastasis within subcutaneous tissue, lymph nodes, or viscera without a detectable primary tumor. Among patients with metastatic melanoma of unknown primary lesion, those with endobronchial metastasis are exceedingly rare. Herein we report a case of an endobronchial and pulmonary metastasis in a patient with melanoma originating from an unknown primary site. The patient without a previous history of melanoma presented with blood-tinged sputum. Fiberoptic bronchoscopy revealed a black polypoid tumor obstructing the posterior basal segmental bronchus of the right lower lobe. A final diagnosis of the malignant melanoma was made based on an immunohistochemical study of the bronchoscopic biopsy specimen. Skin, ophthalmic, oral, and nasal examinations failed to identify occult primary lesions. Subsequent evaluation including positron emission tomography/computed tomography scans did not uncover any abnormalities other than the metastatic pulmonary melanoma. We also describe the characteristic bronchoscopic features of melanoma. Copyright