Primary chondrosarcoma of the lung. A clinicopathologic study.
BACKGROUND: Primary pulmonary chondrosarcoma is a rare neoplasm. A 73-year-old Japanese man had chondrosarcoma in the right lung. The tumor was considered to be of pulmonary origin because of the absence of extrapulmonary primary lesions for 2 years after lung resection. METHODS: The histologic sections were stained with hematoxylin and eosin, conventional special staining, and immunohistochemical staining. The authors discussed the differential diagnosis and growth pattern, in addition to the histopathologic findings in the tumor cells. In a review of the literature, the authors compared the characteristics between the major bronchus (MB) and lung types. RESULTS: Histopathologically, the tumor cells showed atypical cartilaginous differentiation without osteoid formation, benign or malignant-appearing epithelium, or sarcomatous components other than chondrosarcoma. The tumor showed expansive proliferation, invasion through the alveolar spaces, massive proliferation along the bronchial lumen, significant invasion into small vessels, and extrathoracic metastases. The review of the literature showed that the clinical period ending with surgical treatment was longer in the lung tumors than in the MB tumors. CONCLUSIONS: Although MB tumors were reported to be discovered early, the invasion to major arteries or trachea often led to inoperability; however, lung tumors were considered to be resectable until they grew very large, even though the clinical period from onset to surgical treatment was longer in this type. Recent advancements in diagnostic and surgical techniques are expected to promote early discovery and improve prognosis whether the tumor occurs in the MB or lung.