摘要
BACKGROUND Primary malignant melanoma of the lung (PMML) is a rare and highly malignanttumor with a poor prognosis. Here, we report a PMML case diagnosed bycomputed tomography (CT)-guided percutaneous biopsy, describe itspathological features and review relevant literature to improve our understandingof this tumor.CASE SUMMARY A 64-year-old Chinese female presented with productive cough for 7 mo. A chestCT scan showed a large and space-occupying lesion in Lingual lobe. Positronemission tomography-CT revealed multiple nodules located in the superior lobeapicoposterior segment of her left lung. Brain magnetic resonance imagingshowed numerous enhancing nodules, suggesting brain metastasis. AbdominalCT scan did not show any abnormalities. By CT-guided percutaneous biopsy, fourpieces of gray and taupe tissues (1 cm length and 0.1 mm in diameter) wereobtained. After pathologic examination, the tumor was found to consist ofepidermal and nested small round cells, fibrosis and thin-walled blood vessels.The finding was suggestive of malignant melanoma. To confirm the diagnosis,pathological morphology and immunophenotypic features of the biopsyspecimens were observed. The patient denied any history of skin tumors. Noabnormal lesions were detected in other sites of the body. Molecular testing waspositive for wild-type EGFR and KIT gene mutations. Finally, the clinical andpathological findings suggested PMML.CONCLUSION PMML is very rare, and the percutaneous biopsy tissue is limited. Therefore,comprehensive consideration of histology, immunohistochemistry, imaging, andclinical information is important for the diagnosis of PMML.
