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Objective:To investigate the prognostic value of 18F-FDG PET/CT in patients with locally recurrent nasopharyngeal carcinoma (NPC) receiving chemoradiotherapy, and relationships between different metabolic parameters and peripheral blood inflammation markers. Methods:From January 2013 to June 2016, the data of 56 patients (40 males, 16 females, age 27-81 years) with locally recurrent NPC receiving chemoradiotherapy in the First People′s Hospital of Foshan were retrospectively analyzed. The SUV max, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were determined by 18F-FDG PET/CT and peripheral blood inflammation markers within 1 week before treatment were measured. Spearman rank correlation analysis was used to estimate the correlations between metabolic parameters and inflammation markers. According to the ROC curve, the best cut-off values of the SUV max, MTV and TLG were obtained and used to group patients. The Kaplan-Meier method and Cox regression were used to conduct univariate analysis and multivariate analysis of 3-year locoregional failure-free survival (LRFFS) and 3-year overall survival (OS) in patients with locally recurrent NPC. The prognostic value of metabolic parameters in patients with early and advanced recurrent T(rT) stages were compared. Results:MTV was positively correlated with neutrophils, neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and high-sensitivity C-reactive protein (hs-CRP) before treatment in patients with locally recurrent NPC ( rs values: 0.30, 0.30, 0.28, 0.27, all P<0.05); TLG was positively correlated with neutrophils, monocytes, NLR and PLR ( rs values: 0.30, 0.28, 0.32, 0.30, all P<0.05). But there were no correlations between SUV max and peripheral blood inflammation markers ( rs values: from -0.18 to 0.24, all P>0.05). SUV max was an factor affecting 3-year LRFFS of patients undergoing radiotherapy and chemotherapy (hazard ratio ( HR)=3.815(95% CI: 1.278-11.388), P=0.016), while rT stage and MTV were prognostic factors for 3-year OS ( HR values: 4.492(95% CI: 1.474-13.688), 7.238(95% CI: 1.653-31.688), P values: 0.008, 0.009). For patients with advanced rT (rT3-4), the 3-year OS of the MTV≥6.84 cm 3 group was significantly lower than that of MTV<6.84 cm 3 group ( χ2=6.99, P=0.008). Conclusions:SUV max of tumor and MTV before treatment have important prognostic values in patients with locally recurrent NPC receiving chemoradiotherapy, but their predictive effects on prognosis are not the same. The varying effects of local inflammation on metabolic parameters may be one of the important reasons lead to that difference.
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Objective: To explore the value of dual-phase 18F-FDG PET/CT in diagnosis of different types of extrahepatic cholangiocarcinomas (EHCC). Methods: Data of 71 patients with suspected EHCC who underwent preoperative dual-phase 18F-FDG PET/CT scanning were retrospectively analyzed. According to 18F-FDG PET/CT imaging and pathological results, the patients were divided into mass-forming EHCC group (n=20), non-mass-forming EHCC group (n=34) and benign diseases group (n=17). The diagnostic efficiency of dual-phase 18F-FDG PET/CT was calculated. The maximal standardized uptake value (SUVmax), tumor SUVmax/liver SUVmean ratio (T/L) and retention index (RI) of dual-phase 18F-FDG PET/CT were compared in those with positive findings among 3 groups. ROC curves were used, and the AUC were compared. Results: The diagnostic sensitivity of early and delayed 18F-FDG PET/CT for non-mass-forming EHCC was 70.59% (24/34) and 73.53% (25/34), respectively. In all patients with positive findings, SUVmax and T/L of mass-forming EHCC were higher than those of benign diseases (all P0.05). The best cut-off of RISUV was 6.0%. The diagnostic sensitivity and accuracy of dual-phase 18F-FDG PET/CT for non-mass-forming EHCC can be improved with the combination of early phase SUVmax>3.1 and RISUV>6.0%. Conclusion: Dual-phase 18F-FDG PET/CT might be helpful to improving diagnostic accuracy of non-mass-forming EHCC.
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Objective To investigate the differences of acquisition protocols from continuous bed motion (CBM) and step-and-shoot (SS) modes and to observe their effects on image quality and standard uptake value (SUV) in 18 F-fluorodeoxyglucose (FDG) PET/CT.Methods A total of 30 patients (13 males,17 females;40-71 years) who underwent 18F-FDG PET/CT from June 2017 to September 2017 were selected.Simulated acquisition protocols for a specific range (upper margin of the skull to the lower edge of sciatic bone) were established with CBM and SS modes.The differences between 2 modes for actual length requiring for a specific acquisition range and the differences in CT radiation dose were compared.Real PET/ CT scans were performed using CBM and SS modes consecutively,and the differences in image quality and SUV were compared.Paired t test andx2 test were used to analyze the data.Results For the specific acquisition range,the average acquisition length of CBM was reduced by 6.65％ ((87.11 ± 3.78) vs (93.32 ±6.02) cm;t=-7.737,P＜0.001) and the CT radiation dose was reduced by 6.88％ ((812±170) vs (872±192) mGy · cm;t=-6.432,P＜0.001) for each patient compared with the results of SS.There were no significant differences in maximum SUV (SUVmax) and mean SUV (SUVmean) between SS and CBM in normal tissues including liver,bone and waist muscles (t values:from-1.895 to 0.132,all P＞0.05).The SUVmax of leg muscles at the end of the image was significantly higher in SS than that in CBM (1.24±0.53 vs 1.06±0.42;t=3.450,P＜0.01).There were no statistically significant differences in SUVmax and SUV between SS and CBM in 40 FDG high uptake lesions (t values:0.420 and-0.260,both P＞0.05).There were 73.33％ (22/30) patients had images with overall high quality during SS and the percentage was 80.00％ (24/30) during CBM (x2 =0.373,P＞0.05).The percentage of patients with images of high quality at the end was 16.67％(5/30) during SS,which was significantly less than that during CBM (63.33％,19/30;x2 =13.611,P＜0.001).Conclusions For the specific acquisition range,CBM can reduce unnecessary CT scan range and radiation dose compared with SS.There is no significant difference in image quality and SUV from normal tissue and lesion except for the end of the image.
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Objective To investigate the efficacy of SPECT/CT in detecting parathyroid lesions in chronic kidney disease (CKD) with secondary hyperparathyroidism (sHPT) patients.Methods Within 2 weeks before parathyroidectomy (PTX),52 patients of CKD with sHPT underwent 99Tcm-sestamibi (99Tcm-MIBI) dual-phase planar and delayed SPECT/CT scintigraphy.Taking surgical pathology as the golden standards,the sensitivity,specificity and accuracy of dual-phase planar,SPECT,CT and SPECT/CT were calculated and compared.Results Totally 172 lesions were detected in surgical operation,including 13 parathyroidomas (PM),26 adenomatoid hyperplasias (AH) and 133 diffuse parathyroid hyperplasias (PH).The sensitivity of 99Tcm-MIBI dual-phase planar,SPECT,CT and SPECT/CT was 55.81％ (96/172),70.35％ (121/172),79.65％ (137/172) and 81.40％ (140/172),respectively,while the specificity was 92.05％(81/88),90.91％ (80/88),76.14％ (67/88),93.18％ (82/88),the accuracy was 68.08％ (177/260),77.31％ (201/260),78.46％ (204/260) and 85.38％ (222/260),respectively.The sensitivity of SPECT/CT was superior to that of SPECT (x9 =17.053,P＜0.001) and 99Tcm-MIBI dual-phase planar (x2 =44.000,P＜0.001).SPECT/CT was superior to CT (x2 =10.316,P =0.001) for specificity,and superior to CT (x2 =13.136,P＜0.001),SPECT (x2 =14.815,P＜0.001) or 99Tcm-MIBI dual-phase planar (x2=39.706,P＜0.001) for accuracy.Conclusion SPECT/CT fusion imaging is better in localization of parathyroid lesions of CKD with sHPT patients than 99Tcm-MIBI dual-phase planar,SPECT or CT imaging alone.
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<p><b>OBJECTIVE</b>To find a rational way in early detecting the residual tumor in patients with nasopharyngeal carcinoma (NPC) after radiotherapy.</p><p><b>METHODS</b>A total of 47 NPC patients who were diagnosed residual tumor after radiotherapy and treated in our hospital from Dec 2009 to Aug 2012 were included in this study and their clinicopathological and follow-up data were reviewed and analyzed. The patients were checked by nasopharynx MRI, FDG PET-CT and were examined by biopsy of the residual tumors within two weeks after radiotherapy. The diagnosis of relapses was determined by pathological re-examination.</p><p><b>RESULTS</b>All the 47 patients were followed up for 10-42 months. Three of them had nasopharynx relapse. The others had not tumor relapse and their residual tumors disappeared completely. The specificity of MRI, FDG PET-CT and pathological tumor response in diagnosing residual tumors were 9.1%, 77.3%, and 95.5% (P<0.001). Their accuracy rates were 14.9%, 78.9%, and 95.7%, respectively (P<0.001). The M of SUVmax in the team who had moderate and severe pathologic tumor response (team A) was 3.05 and that in the team who had mild pathologic tumor response (team B) was 4.68 (P=0.012). None of patients in the team A had nasopharynx relapse. Three patients in the team B who had SUVmax ≥4 had nasopharynx relapses, and in other 2 patients who had SUVmax <4, the residual tumors disappeared during the following-up. The specificity and accuracy in diagnosing residual tumors were increased when mild pathologic tumor response combined with SUVmax4 were used.</p><p><b>CONCLUSION</b>PET-CT combined with pathologic tumor response is beneficial for early diagnosis of residual nasopharyngeal tumors after radiotherapy.</p>