99Tcm-MDP SPECT/CT显像用于骨肉瘤肺转移的诊断

目的：观察骨肉瘤肺转移的发生率，评价99Tcm-MDP SPECT/CT显像中的骨显像与胸部CT对肺转移的检出效能及其影响因素。方法178例骨肉瘤患者使用SPECT/CT行全身骨显像的同时获得胸部CT，以诊断有无肺转移发生。通过回顾性分析，将影像学诊断结果与最终临床诊断进行对照，计算肺转移的发生率；评价骨显像和胸部CT对肺转移的检出效能；分析转移灶钙化对骨显像检出率的影响；分析血清碱性磷酸酶（ALP）水平在有肺转移与无肺转移者之间、转移灶有钙化与无钙化者之间以及转移灶骨显像阳性与阴性者之间的差异。结果178例患者肺转移的发生率为24．2%；骨显像与胸部CT对其诊断的灵敏度分别为44．2%和100%；特异度分别为100%和89．6%；骨显像对有钙化转移灶的检出率显著高于无钙化转移灶（χ2=8．4，P＜0．01）；患者血清ALP水平与肺转移的发生相关，但与病灶内有无钙化以及病灶是否在骨显像中呈阳性无关。结论骨肉瘤患者肺转移的发生率较高，使用SPECT/CT同时行全身骨显像和胸部CT检查对其检出具有较高诊断价值，尤其适用于血清ALP升高的患者。

99Tcm-MDP SPECT/CT used in diagnosis of pulmonary metastasis from osteosarcoma

Objective To observe the incidence of pulmonary metastasis in osteosarcoma and evaluate the diagnostic efficiency of bone scintigraphy and chest CT in detection of pulmonary metastases and its influential factors. Methods A retrospective study was performed in 178 consecutive patients with osteosarcoma who underwent both bone scintigraphy and chest CT examination simultaneously by using a SPECT/CT instrument. Based on the final clinical diagnosis, incidence of pulmonary metastasis in the group was calculated, and the diagnostic efficacy of bone scintigraphy and chest CT was evaluated, re-spectively. Detection rate of bone scintigraphy was correlated to the status of calcification in metastatic le-sions. Serum alkaline phosphatase （ALP） levels was correlated to the occurrence of pulmonary metastasis, calcification status in metastatic lesions and scintigraphic detections. Results Pulmonary metastasis oc-curred in 24.2%patients of all the patients. In the detection of pulmonary metastasis, sensitivity of bone scintigraphy and chest CT was 44.2%and 100%, respectively, and specificity was 100%and 89.6%, re-spectively. Lesion detection on bone scintigraphy was affected by the status of calcification in metastat-ic tumors （χ2=8.4, P＆lt;0.01）. It was found that the serum ALP levels was correlated to the occurrence of pulmonary metastasis, but not to the calcification or scintigraphic detections. Conclusions The risk of pulmonary metastasis in patients with osteosarcoma is higher. Using SPECT/CT to obtain bone scintigraphy and chest CT simultaneously will have a higher diagnostic value for detection of pulmonary metastasis, es-pecially for those patients who with elevated serum ALP.