Primary Melanoma of the Lung: A Clinicopathologic and Immunohistochemical Study of Eight Cases

摘要: Primary malignant melanoma of the lung (PMML) is an uncommon neoplasm that may be confused with more conventional types cancer. Although previously proposed criteria for diagnosis, including presence in situ component, are often difficult to satisfy, this lesion characterized by a poor prognosis, ultimately leading patient death. We report eight cases PMML presented as solitary, central endobronchial neoplasms, resulting picture closely resembled carcinoid tumor or poorly differentiated non-small-cell carcinoma lung. The mean age at diagnosis was 51 years (range 45-71). patients included one woman and seven men. histologic growth pattern varied from organoid fascicular epithelioid spindled cells hyperchromatic vesicular nuclei, prominent eosinophilic nucleoli, abundant clear cytoplasm occasional intranuclear cytoplasmic inclusions. A bronchial component present four cases. Initial interpretations tumor, carcinoma, melanoma. Melanin all neoplasms on hematoxylin eosin staining, although very focally case, Fontana-Masson positive Immunohistochemically, diffuse strong positivity S-100, HMB-45, vimentin tumors tested. All were negative cytokeratin, CAM 5.2, chromogranin. Ultrastructural examination eighth case showed dysmorphic premelanosomes but no neurosecretory granules. None had disseminated disease presentation, underwent surgical resection (seven lobectomies excision). In series, primary aggressive postoperative course, five dying metastatic 4 32 months after (median 14 months). Two alive 30 surgery, evidence 108 surgery last follow-up. Metastatic identified various sites, lungs, adrenal glands, liver, mesentery, brain, bone. herein indicate should differential tumors.