| BackgroundBecause of the aged tendency of our society, the increase of tumor incidence, theimprovement of medical treatment level, as well as the lengthen of patients’ survival, theincidence of bone metastases increased gradually。Spinal bone metastases can be caused byany tumors, more than60%spinal bone metastases due to lung cancer, breast cancer andprostate cancer. Bone pain due to bone metastases seriously reduce the patient’s quality oflife and survival time, the early detection of bone metastases in cancer patient and activetreatment can effectively improve the quality of life and survival time. Imagingexamination is recognized as a effective methods in the diagnosis of bone metastases. Atpresent, the commonly used imaging diagnostic methods are X-ray, CT, MR and wholebody bone scan. Various methods have its advantages and disadvantages, CT and wholebody bone scan in the diagnosis of bone metastases are more reliable, the joint applicationof these two methods is getting more and more attention.PurposeTo explore the difference between bone scan and computed tomography (CT) whenthey are used to diagnose the spinal bone metastasis and to determine the usefulness ofadditional CT examination in the spine bone metastatic area found by bone scan.Materials and methods1.140patients with suspected malignant tumor bone metastases were referred to bonescan and CT scan using SPECT/CT。The imagies of whole body bone scan and CT scanwere interpreted by2experienced nuclear medicine physicians.2. Clinical diagnosing standard of bone metastases: proved by histological examination，bone scans or CT scan shows extensive bone transfer or shows more transferin the follow-up check after more than3months， cooperation with other imagingexamination diagnosis of bone metastases.Result140cases of patients, according to the clinical diagnostic criteria,53cases wereconfirmed to be spinal bone metastases, the rest of the patients were not.1. Whole body bone scan found65cases of spinal bone metastases,18cases of falsepositives,75cases were ruled out of spinal bone metastases,1case of false negative.Using whole body bone scan to diagnose spinal bone metastases of malignant tumors, itssensitivity was88.7%, specificity was79.3%, false positive rate was20.7%, false negativerate was11.3%，positive Predictive value was72.3%, negative predictive value was92.0%and the accuracy was82.9%2. Whole spine CT found48cases of spinal bone metastases,5cases of false positives,92cases were ruled out of spinal bone metastases,10case of false negative. Using wholespine CT scan to diagnose spinal bone metastases of malignant tumors, its sensitivity was81.1%, specificity is94.3%, false positive rate was5.7%, false negative rate was18.9%，positive predictive value was89.6%, negative predictive value was89.1%and theaccuracy was89.3%.3. BS combined CT imaging found51cases of metastatic tumor,3cases of falsepositives,89cases were ruled out of spinal bone metastases,5cases of false negative.Using BS combined CT to diagnose spinal bone metastases of malignant tumors, thesensitivity was90.6%, specificity was96.6%, false positive rate was3.4%,false negativerate was9.4%, positive predictive value was94.1%, negative predictive value was94.4%,and the accuracy rate was94.3%.4. CT scan’s specificity and positive predictive value was significantly higher thanthat of bone scan for diagnosis of bone metastases. BS combined CT’s, its specificity,accuracy, positive predictive value were significantly higher than that of BS and theaccuracy rate was significantly higher than that of CT. The other differences had no statistical significance.5.42cases with spine metastases could count the bone metastases, whole body bonescan checked out53vertebra thoracalis metastases,23lumbar vertebra metastases whichwas more than CT (46vertebra thoracalis metastases，21lumbar vertebra metastases)。CT checked out7cervical vertebra metastases,6sacral vertebrae metastases which wasmore than whole body bone scan (4cervical vertebra metastases，4vertebraemetastases)。Due to lack of pathologic diagnosis, we could not decide was there differencebetween two groups.Conclusion1.99mTc-MDP Bone scan and CT scan is both ideal methods to find spinal bonemetastases.2. The study tell us that the specificity and positive predictive value of bone scan arelower than that of CT, with CT can know more nature of the lesion.3. The study show bone scan combined CT’s specificity, accuracy, positive predictivevalue is significantly higher than single bone scan and accuracy is significantly higher thansingle CT imaging in diagnosis of spine bone metastases, Bone scan combined CT’sdiagnostic performance is better than a single imaging.4.99mTc-MDP whole body bone scan and computed tomography (CT) in the checkout rate of spine bone metastases lesions has differences but we need take another study todefine if it is mean.5. The specificity and positive predictive value of bone scanning in the diagnose ofspine bone metastatic can be improved with the help of CT. |
