肺转移瘤 〔Metastatic tumors of the lung〕
• 肺是转移瘤的好发脏器，大量尸检结果显示，有20％～54％胸外恶性
肿瘤的病人发生肺转移。肺转移的途径可以是血行播散、淋巴道转移 或邻近器官直接侵害。以绒毛膜癌、乳腺癌多见，恶性软组织肿瘤、 肝癌、骨肉瘤和胰腺癌次之；还有甲状腺癌、肾癌、前列腺癌和肾胚 胎癌等。
• Hemorrahgic Metastasis from Choriocarcinoma 〔绒毛膜癌〕Radiologic Findings
Chest radiograph shows multiple, ill-defined nodular opacities in both lungs. HRCT scan shows multiple, ill-defined nodules with halo of ground glass attenuation in the periphery zones of both lungs. Diagnosis was made based on clinical history of choriocarcinoma and radiologic findings. Serum HCG level was as high as 59,100 IU/ml. Brief Review The incidence of pulmonary metastases varies with the primary tumor and the stage of the disease. In autopsy series the most common sources of metastases to the lungs include tumors of breast, colon, kidney, uterus, prostate, head, and neck. Tumors such as choriocarcinoma, osteosarcoma, Ewing’s sarcoma, testicular tumors, melanoma and thyroid carcinoma have a high incidence of pulmonary metastases, but because they are not as prevalent in the population, lung deposits from these tumors are encountered less frequently . Hematogenous metastases usually result in multiple, large, well-defined nodules and tend to involve mainly the lower lung zones and frequently have a peripheral distribution. On occasion, if the metastases have bled into the surrounding lung, they show ill-defined edges. The reported incidence of pulmonary metastasis of choriocarcinoma has ranged from 5.1- 67% . The pattern of thoracic metastasis from choriocarcinoma is variable, including pulmonary nodules with surrounding hemorrhage, miliary nodules, nodule or masses with arteriovenous aneurysm formation, and pulmonary or pleural metastasis with spontaneous hemothorax .
