全身^(18)F-FDG PET-CT在脑转移瘤诊断中的应用

Detection of the primary tumor in brain metastasis by whole body ^(18) F-FDG PET-CT

目的评价全身^(18)F-氟脱氧葡萄糖(^(18)F-fluorodeoxyglucose,^(18)F-FDG)正电子发射断层扫描(positron emission tomography,PET)-CT显像在脑转移瘤的诊断及寻找原发灶中的应用价值。方法对全身脑转移瘤及可疑脑转移瘤的212例行PET-CT检查,并回顾性分析其临床资料。结果 212例中,肺原发恶性病变158例(74.5%),其他部位原发恶性肿瘤40例(18.9%),可疑脑原发病变11例(5.2%),未发现原发灶的脑转移瘤3例(1.4%)。未明确原发灶的48例中,全身PET-CT显像发现原发灶34例(70.8%),其中肺恶性病变来源26例(54.2%)、其他部位来源恶性肿瘤8例(16.7%)。单纯胸部薄层CT扫描诊断为肺恶性病变来源者22例(45.8%);CT性质不明确的孤立性肺结节4例,结合临床及全身PET-CT显像特征均诊断为肺恶性病变。结论全身^(18)F-FDG PET-CT显像有利于发现脑转移瘤的原发灶。脑转移瘤来源于肺恶性病变较多。胸部薄层CT扫描有利于对原发灶的初步诊断。

Objective To evaluate the value of whole body18F-fluorodeoxyglucose （FDG） positron emission tomography （PET）-CT in diagnosis of primary tumor in brain metastasis. Methods 18F-FDG PET-CT in 212 patients with initial complains of multiple metastatic tumors in the brain were analyzed retrospectively.Results In 212 cases, 158 cases （74. 5%） were primary pulmonary malignant lesions, 40 cases （18.9%） with primary malignant tumors from other parts, 11 cases （5.2%） with suspected primary brain tumors, and 3 （1.4%） cases of metastasis in the brain but not found the primary lesion. Among the 48 cases with unknown origin, 34 cases （70. 8%） were found of primary lesions by whole body PET-CT imaging, including 26 cases from lung （54.2%）, 8 cases （16.7%） from other parts of the body. Twenty two （45.8%） cases were diagnosed with pulmonary malignant origin by simple chest thin slice CT scan. Four cases diagnosed of pulmonary solitary nodules but their property is not clear by CT scan. They were finally diagnosed as lung malignant by clinical characteristics combined with whole body PET-CT imaging. Conclu- sion The whole body scan of 18F-FDG PET-CT is benefit for finding out the primary tumors of brain metastasis. Most of brain metastasis originates from malignant tumor of lung. Chest thin-slice CT scan plays an important role in the initial diagnosis of the primary tumor in brain metastasis.