ABSTRACT
Objective To evaluate the value of semi-quantitative indices of 68Ga-prostate specific membrane antigen (PSMA)-11 PET/CT in differentiating malignant and benign prostate lesions.Methods From November 2017 to June 2018,30 patients (age:52-86 years) who underwent 68Ga-PSMA-11 PET/CT imaging in the Third Affiliated Hospital of Sun Yat-sen University were retrospectively analyzed,and the serum total prostate specific antigen (tPSA) and free prostate specific antigen (fPSA) were examined within 1 week before PET/CT imaging.Semi-quantitative indices of 68Ga-PSMA-11 PET/CT on prostate lesions were measured by automatic segmentation algorithm method,including PSMA-related lesion volume (VPSMA),maximum standardized uptake value (SUVmax),mean standardized uptake value (SUVmean),peak standardized uptake value (SUVpeak) and total lesion uptake value of PSMA (TLUPSMA).The indices were compared between malignant and benign prostate lesions,and the optimal cut-off values for differentiating malignant and benign prostate lesions were obtained by receiver operating characteristic (ROC) curve analysis.Results According to the pathological results,19 patients had malignant lesions and 11 were with benign diseases.The differences of tPSA,SUVmax,SUVmean SUVpeak and TLUPSMA between malignant and benign prostate lesions were statistically significant (u values:17.00-48.00,all P＜0.05),but there were no significant differences of fPSA,fPSA/tPSA and VPSMA between 2 groups (u values:64.00-99.00,all P＞0.05).The optimal cut-off value of tPSA was 18.30 μg/L for differentiating malignant and benign prostate lesions,with sensitivity of 13/17 (PSA of 2 patients were missing),specificity of 9/11 and area under curve (AUC) of 0.743.The optimal cut-off values of SUVmax,SUVmean and SUVpeak were 5.50,3.09 and 3.56,respectively,with all corresponding sensitivity of 18/19,all specificity of 9/11,and AUC of 0.902,0.907 and 0.919,respectively.The optimal cut-off value of TLUPSMA was 54.81 cm3,with sensitivity of 14/19,specificity of 9/11 and AUC of 0.804.Conclusion The semi-quantitative indices of 68Ga-PSMA-11 PET/CT are valuable for differentiating malignant and benign prostate lesions,in which SUVpeak is superior to other indices.
ABSTRACT
Objective This study was conducted to assess the accuracy of [18F] fiuorodeoxyglucose-positron emission tomography/computed tomography (18FDG PET-CT) in detection of pelvic nodal metastases in endometrial cancer.Methods Patients with endometrial cancer from January 2015 to June 2017 confirmed by the postoperative pathology were retrospectively analyzed.30 patients finished PET-CT before operation.The findings on histopathology were compared with 18FDG-PET/CT findings to calculate the sensitivity,specificity,positive predictive value (PPV),negative predictive value (NPV),and accuracy of 18FDG-PET/CT.To analyze the efficacy of maximum standardized uptake (SUVmax) and lymph node maximum standardized uptake (LN-SUVmax) of PET-CT in the diagnosis of pelvic lymph node metastasis.Resuits For detection of pelvic nodes,based on patient analysis,18FDG-PET/CT had a sensitivity of 75.0％,specificity of 88.5％,PPV of 50.0％,NPV of 95.8％ and accuracy of 86.7％.Based on a nodal region analysis,18FDG-PET/CT had a sensitivity of 83.3％,specificity of 98.3％,PPV of 55.0％,NPV of 99.6％,and accuracy of 98.3％.When maximum standardized uptake values (SUVmax) ＞ 8,area under curve (AUC) =0.64,Yonden Index =0.42.When maximum standardized uptake values of lymphonodus (LN-SUVmax) ＞ 3 (AUC =0.79,Yonden Index =0.63),the sensitivity and specificity of diagnosis of lymph node metastasis were 100％,42.31％,and 75.0％,88.5％,but without statistically significant difference.Although AUC of LN-SUVmax was higher than SUVmax of primary lesion,but the difference was not statistically significant (P ＞ 0.05).Conclusions 18 FDG-PET/CT has high specificity,NPV for detection of pelvic LN metastasis area in endometrial cancer,which can provide preoperative basis for patients with endometrial cancer to avoid lymph node resection,thereby reducing the risk of early endometrial cancer surgery and improving the quality of life after surgery.We concluded that,there were no exact cutoffs of SUVmax for the prediction of lymph node metastases,neither primary lesion,nor lymph node.There is clearly a need for multicenter,large-scale trials to find out better parameters in judging metastasis of lymphnodes.
ABSTRACT
Objective To investigate the role of pulmonary ventilatioa/perfusion imaging in evaluating thrombolytic therapy in pulmonary embolism (PE).Methods Pulmonary ventilation/perfusion imagng was performed before and one week and three months after thrombolytic therapy in 43 patients with acute PE.Results Among 421 abnormal pulmonary segments in 43 PE cases,199(47.3%) and 231(54.9%) segments were restored to normal 1 week and 3 months later (P<0.05).Of two groups,more abnormal pulmonary segments were restored to normal in those with less than one week's onset (P<0.01).Conclusion As a non-invasive diagnostic method, pulmonary ventilation/perfusion imaging plays an important role in evaluating the therapeutic effectiveness of thrombolytic therapy in patients with PE.