Objective To assess the role of 68Ga-N,N′-bis(2-hydroxy-5-(carboxyethyl)benzyl) ethylenediamine-N,N′-diacetic acid(HBED-CC)-(Ahx)Lys-CO-Glu(PSMA-11) PET/CT on the detection of metastatic lesions from castration-resistant prostate cancer (CRPC).Methods Sixteen patients with CRPC who underwent 68Ga-PSMA-11 PET/CT between January 2015 and November 2015 were recruited in this study.Mean age of patients was (72±9) years.The PSA levels were 4-12 356 μg/L, Gleason score was 7-10.PET/CT was performed at 1 h postinjection of 68Ga-PSMA-11.Patient-based analysis and lesion-based analysis were performed.ROI analysis was used to calculate the tumor uptake (SUVmax).Final diagnosis was based on histopathology and results of other imaging examinations(99Tcm-MDP imaging, MRI).χ2 test was used to compare the diagnostic efficiencies of PET and CT.Results No adverse effects were observed in patients.68Ga-PSMA-11 PET/CT showed moderate physiologic uptake in salivary glands and proximal small intestine, with predominant tracer clearance by the kidneys.All patients were positive on 68Ga-PSMA-11 PET/CT.Bone metastasis was found in 16 patients, liver metastasis in 2 patients (5 lesions), and lymph node metastasis in 4 patients (26 lesions).The SUVmax of liver, lymph node and bone metastases were 15.06±2.77, 7.54±5.20, 19.01±16.96, respectively.The diagnostic sensitivity, specificity and accuracy on bone metastasis with 68Ga-PSMA-11 PET and CT were 96.30%(52/54) vs 61.11%(33/54), 3/3 vs 1/3, 96.49%(55/57) vs 59.65%(34/57).The sensitivities and accuracies of the two modalities were significantly different(χ2=19.943, 22.593, both P<0.01).Conclusions 68Ga-PSMA-11 PET/CT could precisely detect both primary and metastatic lesions of CRPC, suggesting that it is of great value for the clinical management and treatment.

Objective To investigate the clinical value of 18F-FDG PET/CT in diagnosing G3 NEN and compare it with 68Ga-DOTA-NOC PET/CT.Methods Twenty-three patients (12 males,11 females;average age (63± 12) years) diagnosed of NEN between January 2006 and November 2016 were retrospectively recruited in this study:11 patients with gastroenteropancreatic NEN (GEP-NEN),10 with G3 NEN in lungs,1 with malignant pheochromocytoma and 1 with G3 NEN of unknown primary site.All patients underwent 18F-FDG PET/CT for staging and evaluation of biological behavior,and 9 of them also underwent 68Ga-DOTA-NOC PET/CT within 1 week.Image interpretation was analyzed by visual and semi-quantitative analysis,and SUVmax was calculated.Results All 23 cases showed positive results on 18F-FDG PET/CT (100％,23/23),with primary tumor SUVmax 10.56±3.94.Compared with 18F-FDG PET/CT,the positive detection rate of 68Ga-DOTA-NOC PET/CT was lower (6/9 vs 9/9),with primary tumor SUVmax 14.24± 10.00.There were 22 patients with distant metastasis.The most frequent metastatic sites associated with G3 NEN in lungs were lymph nodes and bones,while those with GEP-NEN were lymph nodes and the liver.In one patient with non-functional NEN,some metastatic lesions showed negative results on 18F-FDG PET/CT but positive results on 68 Ga-DOTA-NOC PET/CT.Conclusions 18 F-FDG PET/CT has higher diagnostic ability for G3 NEN and may serve as a useful tool for evaluating biological behavior of G3 NEN.68Ga-DOTA-NOC PET/CT is valuable as a complementary diagnostic tool in a small proportion of high differentiated G3 NEN.

Objective To evaluate the combined application of the maximum standardized uptake value (SUVmax) of 68Ga-N,N'-bis (2-hydroxy-5-(carboxyethyl) benzyl) ethylenediamine-N,N'-diacetic acid (HBED-CC)-(Ahx) Lys-CO-Glu (PSMA-11) PET/CT imaging and the apparent diffusion coefficient (ADC) value of MRI in the differential diagnosis of prostate cancer (PCa).Methods Seventy untreated patients (age:(68.3± 12.1) years) with suspected PCa between December 2016 and April 2018 were prospectively studied.All patients underwent PET/CT and MRI examinations.The SUVmax and average ADC value were measured as diagnostic parameters,and the SUVmax/ADC ratio was calculated.The sensitivity and specificity of the 3 parameters were calculated by receiver operating characteristic (ROC) curve analysis.Results Of the 70 patients,31 were pathologically diagnosed as benign diseases and 39 were as PCa.The diagnostic sensitivity and specificity of average ADC value for PCa were 81％ and 72％,respectively,with a threshold value of 1.08× 10-3 mm2/s (b=1 000 s/mm2).The diagnostic sensitivity and specificity of SUVmax were 82％ and 71％ for PCa with a critical value of 7.69,and those were 72％ and 93％ with SUVmax/ADC ratio of 11.87.Conclusion The combination of 68Ga-PSMA-11 PET/CT and MRI can improve the diagnostic specificity for PCa,and the SUVmax/ADC ratio is a valuable differential diagnostic index.

Objective To investigate the safety and efficacy of 177Lu-prostate specific membrane antigen (PSMA)-617 in the treatment of metastatic castration-resistant prostate cancer (mCRPC).Methods From August 2017 to September 2018,11 patients(average age 70.6 years) with mCRPC who underwent 177Lu-PSMA-617 therapy in Nanjing First Hospital were studied.All patients underwent 68Ga-PSMA-11 PET/CT before therapy to assess the tumor radioactive uptake.Blood routine examination and renal function test results were documented before and after therapy to assess the safety.The efficacy was reflected by the changes of prostate specific antigen (PSA) levels and maximum standardized uptake value (SUVmax) on 68Ga-PSMA-11 PET/CT imaging.Paired t test and Wilcoxon's sign rank test were used to analyze the data.Results No acute side effects were observed after therapy of 177Lu-PSMA-617.There were no statistically significant differences after therapy in WBC counts,RBC counts,and PLT,as well as Hb levels (t values:-0.28-1.11,all P＞ 0.05).No kidney toxicity was found.The PSA level after 177Lu-PSMA-617 therapy was significantly lower than that before therapy (80.70 (14.29,1 538.00) μg/L vs 604.60 (88.41,3 980.00) μg/L;u =59,P =0.023).Of the 11 patients,only 2 had elevated PSA levels and disease progression,while the other 9 patients had varying decreases,of which 2/11 decreased by ＞30％ and 7/11 decreased by ＞50％.After therapy,SUVmax of metastatic lesions and metastatic lymph nodes were decreased in 9 and 2 patients respectively.Conclusions 177Lu-PSMA-617 has a good therapeutic value for mCRPC.It is safe and has no obvious side effects.

Objective To assess the role of 68Ga-N,N'-bis (2-hydroxy-5-(carboxyethyl) benzyl) ethylenediamine-N,N'-diacetic acid(HBED-CC)-(Ahx) Lys-CO-Glu(PSMA-11) PET/CT on the detection of metastatic lesions from castration-resistant prostate cancer (CRPC).Methods Sixteen patients with CRPC who underwent 68Ga-PSMA-11 PET/CT between January 2015 and November 2015 were recruited in this study.Mean age of patients was (72±9) years.The PSA levels were 4-12 356 μg/L,Gleason score was 7-10.PET/CT was performed at 1 h postinjection of 68Ga-PSMA-11.Patient-based analysis and lesionbased analysis were performed.ROI analysis was used to calculate the tumor uptake (SUVmax).Final diagnosis was based on histopathology and results of other imaging examinations(99Tcm-MDP imaging,MRI).x2 test was used to compare the diagnostic efficiencies of PET and CT.Results No adverse effects were observed in patients.68Ga-PSMA-11 PET/CT showed moderate physiologic uptake in salivary glands and proximal small intestine,with predominant tracer clearance by the kidneys.All patients were positive on 68Ga-PSMA-11 PET/CT.Bone metastasis was found in 16 patients,liver metastasis in 2 patients (5 lesions),and lymph node metastasis in 4 patients (26 lesions).The SUVmax of liver,lymph node and bone metastases were 15.06±2.77,7.54±5.20,19.01± 16.96,respectively.The diagnostic sensitivity,specificity and accuracy on bone metastasis with 68Ga-PSMA-11 PET and CT were 96.30％(52/54) vs 61.11％(33/54),3/3 vs 1/3,96.49％ (55/57) vs 59.65％ (34/57).The sensitivities and accuracies of the two modalities were significantly different(x2=19.943,22.593,both P＜0.01).Conclusions 68Ga-PSMA-11 PET/CT could precisely detect both primary and metastatic lesions of CRPC,suggesting that it is of great value for the clinical management and treatment.

Objective:To evaluate the feasibility and efficacy of 68Ga-PSMA PET/CT-guided targeted prostate biopsy for the diagnosis of clinically significant prostate cancer(csPCa). Methods:This retrospective analysis allocated 89 patients with elevated PSA levels between 4.0-20.0 ng/ml to PET group(n=48) or TRUS group(n=41) between September 2017 and June 2019. Patients with PSMA-avid lesions (SUV max≥8.0) underwent PET-TB via a single-puncture percutaneous transgluteal approach (n=19), while patients with negative PSMA-PET underwent systematic TRUS-GB (n=29). Patients in the TRUS group who did not get 68Ga-PSMA PET/CT examination underwent TRUS-GB directly (n=41). The mean age, prostate volume, PSA value of PET group and TURS group were (71.2±9.1) years vs. (68.0±12.0) years, (62.9±29.1)ml vs. (65.4±38.9)ml , 8.8(6.6, 13.6) ng/ml vs. 9.8(7.1, 13.1)ng/ml, respectively (all P>0.05). The diagnostic efficacy and difference of PCa and csPCa between the two groups were compared. PET-TB adopts a new mode of percutaneous gluteus approach and carries out precise image fusion of PSMA-PET/CT and pelvic CT in the same machine and in the same position (prone position). Under the direct guidance of CT, the biopsy is performed with only one precise puncture. Results:PCa and csPCa were detected in 27/89(30.3%)and 20/89(22.5%)in all patients. PET group detected significantly more cases of PCa and csPCa than those of TRUS group [PCa: 41.7%(20/48) vs. 17.1%(7/41), χ2=6.328; csPCa: 33.3%(16/48) vs. 9.8%(4/41), χ2=7.055, P<0.01]. Of 19 patients with PSMA-PET positive, PET-TB detected 16 cases of PCa(84.2%) by a single needle puncture, and the proportions of cancer tissues were ≥80% in 2, 50%-79% in 8, and <50% in 6 cases. Among these, Gleason score was underestimated by biopsy histopathology in 2 patients. Of 3 patients with PET-TB negative, 1 case of low-risk PCa(Gleason 3+ 3) was detected by complementary TRUS-GB. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy of 68Ga-PSMA PET/CT(SUV max≥8.0) for the diagnosis of csPCa were 73.9%(14/19), 93.1%(27/29), 87.5%(14/16), 81.3%(26/32)and 85.4%(41/48), respectively. For PET-TB, only one patient had slight symptoms of haematuria after the puncture, no cases of hematochezia, hemospermia, urinary retention or pelvic infection were observed. Conclusions:68Ga-PSMA PET/CT is a feasible novel puncture technique that may serve as a triage tool for prostate biopsy, and PET-TB may improve the detection rate of csPCa compared with TURS-GB, especially in patients with serum PSA 4.0-20.0 ng/ml.

This study reviewed 37 patients who received neoadjuvant ADT in our center and analyzed the change of 68Ga-PSMA PET/CT before and after treatment. This study found that neoadjuvant ADT significantly reduced the tumor visibility on 68Ga-PSMA PET/CT.

Objective: To synthesis ¹⁷⁷Lu-prostate specific membrane antigen (PSMA)-I&T with automated module, evaluate the biodistribution and pharmacokinetics in mice and study the targeting property in human prostate cancer cell line LNCaP Clone FGC. Methods: The iQS-TS automated module was applied in labeling ¹⁷⁷Lu-PSMA-I&T. Radiochemical purity and stability were determined with high performance liquid chromatography (HPLC). The biodistribution was observed in normal ICR mice and U-SPECT/CT imaging was performed in LNCaP Clone FGC tumor-bearing mice. Independent-sample t test was used to analyze the data. Results: ¹⁷⁷Lu-PSMA-I&T was stable in vitro and in vivo, with the radiolabeled yield of (91.5±4.9)% and radiochemical purity >99%. The half maximal inhibitory concentration (IC₅₀) of ¹⁷⁷Lu-PSMA-I&T binding to LNCaP Clone FGC cells was (26.74±3.53) nmol/L. The uptake of ¹⁷⁷Lu-PSMA-I&T by LNCaP Clone FGC cells increased with time and significantly decreased after the inhibitor addition (t values: 4.301-27.483, all P<0.05). ¹⁷⁷Lu-PSMA-I&T was cleared from blood rapidly and predominantly excreted by kidneys. Significant radioactive uptake was observed in tumors with a long retention time. Conclusion ¹⁷⁷Lu-PSMA-I&T can be produced in a convenient and efficient procedure using iQS-TS automated module, with good biological properties and excellent affinity and targeting property towards prostate cancer cells, which making it a potential radiopharmaceutical for prostate cancer therapy.

AIM: To evaluate the combining ability of prostate-specific membrane antigen (PSMA) targeted radioactive drug