parenchymal lung metastases are common in malignant melanoma with various documented manifestations on computed tomography ( ct ) . we report an uncommon case of a hyperdense endobronchial metastasis from melanoma and discuss the differential diagnosis for an endobronchial mass in an adult . a 57-year - old man with a history of right lower extremity cutaneous melanoma , who had undergone first and second toe amputation 3-years prior , presented with dyspnea and black - colored sputum . chest radiograph revealed a collapsed left lung , pathologic fracture of the left sixth rib , and a destructive mass involving the right posterior fifth rib [ figure 1 ] . non - enhanced ct ( nect ) of the chest showed a hyperdense mass with a mean density of 56 hounsfield units within the left main bronchus , resulting in postobstructive left lower lobe collapse [ figure 2a and b ] . in addition , there were two hyperdense left lower lobe intraparenchymal masses , one of which was lobulated [ figure 2c ] . there were also lytic bone lesions in the right scapula ( not shown ) and thoracic vertebrae [ figure 2d ] . contrast - enhanced ct ( cect ) through the lower chest demonstrated heterogeneous enhancement of the left lower lobe masses [ figure 3 ] . bronchoscopy revealed a black - colored hemorrhagic endobronchial mass that was confirmed on histopathology to be an endobronchial metastasis from melanoma [ figure 4 ] . the patient was treated with imatinib ( gleevec ) ( novartis pharmaceuticals , east hanover , nj , usa ) . 57-year - old man presenting with dyspnea and black - colored sputum diagnosed with endobronchial metastasis from melanoma . posteroanterior chest radiograph demonstrates complete collapse of left lung , pathologic fracture of left sixth rib ( arrow ) , and destructive mass ( arrowhead ) involving the right posterior fifth rib . 57-year - old man presenting with dyspnea and black - colored sputum diagnosed with endobronchial metastasis from melanoma . axial ct images at a mid level in the chest in ( a ) lung window and ( b ) soft tissue window show a hyperdense mass ( arrow ) in the left main bronchus with postobstructive collapse and leftward mediastinal shift . ( c ) axial ct image of a lower level in the chest demonstrates an additional hyperdense lobulated left lower lobe mass ( arrow ) . ( d ) coronal ct image shows a lytic lesion in a thoracic vertebra ( arrow ) . 57-year - old man presenting with dyspnea and black - colored sputum diagnosed with endobronchial metastasis from melanoma . contrast - enhanced axial ct image through the lower chest demonstrates heterogeneous enhancement of the left lower lobe mass ( arrow ) . 57-year - old man presenting with dyspnea and black - colored sputum diagnosed with endobronchial metastasis from melanoma . microscopic findings : staining of endobronchial biopsy specimen with hematoxylin and eosin shows pigment - laden cells , indicative of metastatic melanoma ( 400 ) . metastatic melanoma involves the lungs in up to 71% of cases and the thorax is the most common site of disease relapse . ct findings of metastatic melanoma to the lungs include pulmonary nodules ( occasionally in a miliary pattern ) , feeding vessels associated with hematogenous lung metastases , postobstructive atelectasis , and hilar / mediastinal lymphadenopathy . endobronchial metastasis from melanoma is uncommon and not well - documented . in an autopsy series of 21 cases of pulmonary metastatic melanoma , only two cases showed endobronchial involvement . primary melanoma of the bronchus is a rare diagnosis of exclusion if no primary site of melanoma is identified . the presence of known cutaneous melanoma and multiplicity of findings in this case make metastatic melanoma the likely diagnosis , rather than primary melanoma of the bronchus . the high attenuation of melanoma metastases on nect in this case is likely secondary to the hemorrhagic nature of the masses . similarly , direct correlation has been shown between the degree of hemorrhage within an intracranial melanoma metastasis and its hyperdensity on nect . staging work - up of metastatic melanoma includes brain magnetic resonance imaging and either cect or positron emission tomography ( pet)-ct of the chest , abdomen , and pelvis . pet - ct is more sensitive ( 86% ) and specific ( 91% ) than cect ( 63% sensitivity and 78% specificity ) in detecting melanoma metastases ; however , due to the relatively reduced availability of pet imaging , cect is often the study of choice . preoperative lymphoscintigraphy is performed to identify regional lymph node drainage , in order to help plan a thorough lymph nodal dissection . the postoperative lymphadenectomy site may be followed up with ultrasonography to evaluate for local recurrence . breast , colorectal , and renal cancers are the more likely extrapulmonary malignancies , while sarcoma , melanoma , and head and neck cancers are less likely malignancies . endobronchial metastasis is diagnosed on average 4 years after the initial cancer diagnosis . in our patient , this time interval was 3  years . imaging findings of an endobronchial mass are nonspecific ; therefore , bronchoscopy and biopsy are required for further characterization . primary bronchogenic carcinoma , particularly squamous cell carcinoma , is the most common cause of an endobronchial mass in an adult , but a comprehensive differential diagnosis includes carcinoid , allergic bronchopulmonary aspergillosis ( abpa ) , lymphoma , and metastasis . pulmonary carcinoid represents 1 - 5% of all lung cancers and often displays an endobronchial growth pattern ; up to 92% of pulmonary carcinoid are centrally located . on ct , carcinoid appears as a well - defined ovoid endobronchial nodule with punctate or diffuse calcifications , and demonstrates homogenous enhancement . abpa is seen more commonly in young patients with a history of chronic asthma or cystic fibrosis . hyperdense tubular branching opacities and central bronchiectasis in the upper lobes on ct are pathognomonic of abpa . lymphoma may present as an endobronchial mass , which occurs in 2% of hodgkin 's lymphoma cases and in 1.8% of non - hodgkin 's lymphoma cases . mass - like consolidations and multiple pulmonary nodules may be seen on ct in patients with lymphoma . the differential diagnosis for an endobronchial mass in an adult includes primary bronchogenic carcinoma , carcinoid , allergic bronchopulmonary aspergillosis , lymphoma , and metastases ( particularly from breast , colorectal , and renal cell carcinoma ) . metastatic melanoma should be considered if an endobronchial or parenchymal mass is hyperdense on nonenhanced ct .
parenchymal lung metastases are common in malignant melanoma . 
 however , endobronchial metastatic melanoma is uncommon . in this report 
 , we describe a patient with a hyperdense endobronchial mass diagnosed as a melanoma metastasis . 
 we review the imaging findings of pulmonary metastatic melanoma and discuss the differential diagnosis of an endobronchial mass in adults .