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Objective:To explore whether multi-parametric MRI (mpMRI) combined with 68Ga-prostate specific membrane antigen (PSMA) PET/CT can improve the detection efficiency of clinically significant prostate cancer (csPCa). Methods:Clinical and imaging data of 152 patients (age (68.5±8.5) years) who underwent mpMRI and 68Ga-PSMA PET/CT examination for suspected prostate cancer in the First Affiliated Hospital of the Air Force Medical University from January 2021 to November 2022 were retrospectively analyzed, with the histopathological results from transrectal ultrasound guided biopsy as reference. Lesions with Gleason scores (GS) ≥3+ 4 from the biopsy were diagnosed with csPCa, and lesions with negative biopsy or GS 6 were diagnosed with non-csPCa. MpMRI was evaluated independently by two radiologists according to the Prostate Imaging Reporting and Data System (PI-RADS) version 2.1. The radioactive uptake of 68Ga-PSMA PET/CT in prostate lesions was evaluated by SUV max. The independent-sample t test, Mann-Whitney U test and χ2 test were used to compare differences between the two groups, and then multivariate logistic regression analysis was performed. ROC curves analysis was used to analyze the diagnostic efficacies of individual and combined factors and Delong test was used. Results:There were 85 csPCa and 67 non-csPCa confirmed. Prostate specific antigen (PSA), PI-RADS score and SUV max were significantly different between the csPCa group and the non-csPCa group ( χ2=68.06, U values: -7.66, -8.98, all P<0.001). Multivariate logistic regression analysis indicated that PI-RADS score (odds ratio ( OR)=3.424, 95% CI: 1.651-7.100) and SUV max ( OR=1.931, 95% CI: 1.403-2.658) were independent predictors of csPCa (both P<0.001). ROC curves analysis revealed that the cut-off value for diagnosing csPCa was 4 for PI-RADS score and 5.6 for SUV max. The accuracy of mpMRI and PET/CT alone in csPCa diagnosis was 80%(122/152) (AUC of 0.789(95% CI: 0.711-0.866) with the sensitivity and specificity of 91%(77/85) and 67%(45/67)), and 87%(132/152) (AUC of 0.876(95% CI: 0.817-0.936) with the sensitivity and specificity of 81%(69/85) and 94%(63/67)), respectively. Several joint models incorporating 68Ga-PSMA PET/CT with mpMRI data were investigated, the model of PI-RADS 5 or PI-RADS 3-4 and SUV max>5.6 showed better performance than mpMRI and PET/CT alone and other joint models ( z values: 2.01-3.64, all P<0.05), with the accuracy of 91%(138/152) (AUC of 0.910(95% CI: 0.857-0.962) with the sensitivity and specificity of 89%(76/85) and 93%(62/67)). Conclusion:MpMRI combined with 68Ga-PSMA PET/CT can significantly improve the detection efficiency of csPCa, with the principal effect being improved in risk stratification of PI-RADS 3-4 lesions in mpMRI.
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【Objective】 To explore the clinicopathological characteristics and comprehensive treatment strategies of prostate mucosa adenocarcinoma under multidisciplinary diagnosis and treatment (MDT) mode. 【Methods】 Data of two patients with typical prostate mucosa adenocarcinoma treated in our hospital during Sep.2020 and Apr.2023 were retrospectively analyzed. 【Results】 In case 1, the clinical manifestation was macroscopic hematuria; multiparametric magnetic resonance imaging (mpMRI) indicated solid prostatic nodules, clinical stage T4N1Mx; initial prostate specific antigen (PSA) was 1.2 ng/mL; 6868Ga-prostate specific membrane antigen PET/CT (68Ga-PSMA PET/CT) suggested abnormal uptake of nuclear lesions in the prostate (SUV4.2-5.3); biopsy results indicated invasive mucinous adenocarcinoma.After prostate and pelvic field radiotherapy + androgen deprivation therapy (ADT) + antihypertensive treatment, lesions were significantly reduced, and hematuria symptoms were relieved.In case 2, the clinical manifestation was dysuria; initial PSA was 91.78 ng/mL; mpMRI suggested invasion of prostate mass into the bladder and clinical stage of T4N1M1b; 68Ga-PSMA PET/CT indicated prostate and pelvic lymph nodes, and multiple bone lesions showed increased nuclide uptake; biopsy results indicated prostate adenocarcinoma with mucinous adenocarcinoma.Initial endocrine treatment was performed.After 3 months, PSA was reduced to 0.083 ng/mL, and imaging showed the tumor was significantly reduced.Robotic-assisted laparoscopic tumor prostatectomy with extended pelvic lymph node dissection was performed, and endocrine adjuvant therapy was continued after surgery. 【Conclusion】 Prostate mucosa adenocarcinoma has different clinicopathological characteristics and prognosis from conventional acinar adenocarcinoma, and the whole-process management under MDT mode is of great value in the diagnosis and treatment of this disease.
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Objective:To establish a method for correction of tail vein extravasation based on PET images and to improve the accuracy of SUV.Methods:The simulation method was established by phantom on Nano PET/CT and images were reconstructed by a three-dimensional ordered-subsets exception maximum algorithm. PET images were analyzed by using the Interview Fusion 1.0 software. The optimal scanning time and the ROI delineated method were found. The accuracy of the simulation method was verified by comparing the activity of simulation method with the mice tail activity measured by the dose calibrator directly on Kunming (KM) mouse ( n=11). Using the simulation method, the impact of extravasation on SUV was proved. Independent-sample t test was used to analyze data. Results:Ten minutes was selected as the optimal scanning time and SUV max 42% threshold was selected as the ROI delineated method. The specific correction formula was as follows: actual activity=image activity/(4.48× V+ 77.05)×100 (0.3 MBq/ml≤leakage concentration<6.5 MBq/ml); actual activity=image activity/(6.65× V+ 71.10)×100 (6.5 MBq/ml<leakage concentration≤14.8 MBq/ml). In the verification experiment, the difference rate between simulated and standard activity was (6.10±2.43)%. In actual operation verification, SUV was underestimated by (6.07±2.67)%. The corrected SUV (0.276±0.078) was not significantly different from the standard SUV (0.277±0.078; t=0.99, P=0.353), while the uncorrected SUV (0.264±0.078) was significantly lower than the standard SUV ( t=7.02, P<0.001). Conclusion:The correction calculation method based on PET images can realize the accurate correction of tail vein leakage activity and the SUV results of animal imaging.
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Objective:To explore the uptake characteristics and temporal changes of 68Ga-fibroblast activation protein inhibitors (FAPIs) and 18F-FDG in the anastomotic site of reconstructed digestive tracts after radical surgery for gastrointestinal adenocarcinoma. Methods:A cohort of 43 patients (28 males, 15 females; age range 28-79 years) who underwent radical surgery for gastrointestinal adenocarcinoma and underwent 18F-FDG PET/CT follow-up between November 2020 and June 2022 in the First Affiliated Hospital of the Air Force Medical University was prospectively included. One week after the 18F-FDG PET/CT examination, 68Ga-FAPI-04 PET/CT imaging was performed. ROIs were drawn on the PET images at the highest uptake level of anastomotic sites of reconstructed digestive tract and abdominal wall incisions, and SUV max and target-to-background ratio (TBR) were determined. χ2 test, one-way analysis of variance, Kruskal-Wallis rank sum test (Bonferroni correction) and Wilcoxon signed-rank test were supplied. Results:There were 86 surgical wounds (13 gastric-intestinal anastomotic sites, 14 esophagus-intestinal anastomotic sites, 16 intestinal-intestinal anastomotic sites, and 43 abdominal wall incisions) included. In 68Ga-FAPI-04 PET imaging, SUV max of gastric-intestinal anastomotic sites was higher than that of abdominal wall incisions, with a statistically significant difference (adjusted P=0.014). The TBR did not show statistically significant differences among different types of surgical wounds ( H=3.88, P=0.275). In 18F-FDG PET imaging, SUV max of gastric-intestinal, esophagus-intestinal, and intestinal-intestinal anastomotic sites were all higher than that of abdominal wall incisions, with statistically significant differences (adjusted all P<0.001). There were no statistically significant differences in TBR among different types of surgical wounds ( H=3.02, P=0.388). In 68Ga-FAPI-04 PET imaging, the TBR of all types of anastomotic sites exhibited a decreasing trend with increasing postoperative time. Except for intestinal-intestinal anastomotic sites, the differences in TBR between < 0.5-year and ≥ 1.5-year groups were statistically significant for other types of surgical wounds (adjusted P<0.05). In 18F-FDG PET imaging, the TBR of abdominal wall incisions showed a decreasing trend with increasing postoperative time. However, the TBR of other types of surgical wounds did not show a decreasing trend, and the differences in TBR among different time groups were not statistically significant ( H values: 0.53-2.75, P values: 0.252-0.768). In comparing the two PET imaging agents, for all surgical wounds within the <0.5-year and 0.5-1.5-year groups, the 68Ga-FAPI-04 TBR was consistently higher than the 18F-FDG TBR ( z values: -3.17 and -2.55, P values: 0.002 and 0.011). However, in the ≥1.5-year group, the TBR values tended to be consistent, and the differences were not statistically significant ( z=-0.70, P=0.485). Conclusions:The 18F-FDG uptake in the anastomotic sites of reconstructed digestive tracts reaches a low level under half a year after surgery and does not significantly change over time, while the 68Ga-FAPIs uptake remains relatively high within the first 1.5 years after surgery but decreases over time. These patterns suggest that clinical attention should be paid to the differential diagnosis of anastomotic inflammation or fibrosis, which resulting in agent uptake and local tumor recurrence.
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Objective:To exploring the uptake of fibroblast activation protein (FAP) inhibitor (FAPI) in pancreatic cancer through 68Ga-FAPI-04 PET/CT imaging, and provide a basis for the FAP-targeted imaging of pancreatic cancer. Methods:Pancreatic cancer-patient-derived tumor xenograft (PDX) mouse models ( n=8) were developed, then 68Ga-FAPI-04 and 18F-FDG microPET/CT imaging were performed (4 in each group). The differences of percentage activity of injection dose per gram of tissue (%ID/g) of 68Ga-FAPI-04 and 18F-FDG were analyzed by independent-sample t test. 68Ga-FAPI-04 and 18F-FDG PET/CT imaging were performed in 5 patients (4 males, 1 female, age: 46-74 (63.0±11.9) years) with pancreatic cancer, and the maximum standardized uptake value (SUV max) of 68Ga-FAPI-04 and 18F-FDG in primary pancreatic cancer and the SUV max ratio of liver metastases to liver tissue were compared by paired t test. Results:MicroPET/CT imaging showed that 68Ga-FAPI-04 was obviously uptaken at all time points in the tumor of PDX mice. The uptake of 68Ga-FAPI-04 in PDX mice 60 min after injection was significantly higher than that of 18F-FDG ((6.58±0.44) and (4.29±0.13) %ID/g; t=4.152, P=0.008 9). PET/CT showed that the SUV max of 68Ga-FAPI-04 in pancreatic cancer was significantly higher than that of 18F-FDG (16.82±3.08 and 5.14±2.20; t=6.893, P=0.000 1) and the SUV max ratio of liver metastases to liver tissue of 68Ga-FAPI-04 was also significantly higher than that of 18F-FDG (4.57±1.47 and 1.30±0.16; t=3.803, P=0.019 1). Conclusion:68Ga-FAPI-04 can be highly uptaken in pancreatic cancer, suggesting that FAP can be a potential target for PET/CT imaging of pancreatic cancer.
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Objective To evaluate the value of DWI and ADC value in monitoring the chemotherapy response of advanced gastric carcinoma dynamically.Methods 42 advanced gastric carcinoma patients who were confirmed by histopathology underwent T2 WI and DWI examinations at pre-chemotherapy,post-chemotherapy 3 d,7 d,30 d and 60 d respectively.The longest diameters of tumor pre-chemotherapy and post-chemotherapy 60 d were measured on axial T2 WI,meanwhile the ADC values at different time points were calculated.The mean ADC value among pre-and post-chemotherapy of each group (PR and SD)was compared.Results The ADC value of PR group increased gradually.The mean ADC value before therapy was statistically lower than those at differ-ent time points post-chemotherapy (P < 0.05).The ADC value of SD group increased gradually from pre-chemotherapy to post-chemotherapy 30 d,and then the ADC value decreased at post-chemotherapy 60 d.The differences of the mean ADC values in differ-ent time points were statistically significant (P < 0.05).Conclusion DWI and ADC value can dynamically,quantitatively and early detect and monitor the chemotherapy response of advanced gastric carcinoma.