Technetium-99m-methylene diphosphonate single photon emission computed tomography/computed tomography combined with prostate-specific antigen/free prostate-specific antigen ratio for bone metastasis of prostate cancer

BACKGROUND Prostate cancer(PC)is one of the most common malignant tumors in men,and bone metastasis is one of its common complications,which seriously affects the quality of life and prognosis of patients.AIM To investigate the diagnostic value of technetium-99m-methylene diphosphonate(99mTc-MDP)single photon emission computed tomography(SPECT)/CT imaging combined with the serum prostate-specific antigen(PSA)/free PSA ratio for PC bone metastasis(PCBM).METHODS One hundred patients with PC who visited the Hospital of Chengdu University of Traditional Chinese Medicine from January 2020 to January 2022 were recruited as the experimental(Exp)group,while 30 patients with benign prostatic lesions(BPLs)were recruited as the control(Ctrl)group.All patients underwent 99mTc-MDP SPECT/CT imaging and serum PSA/fPSA testing.The SPECT/CT imaging results and serum PSA/fPSA ratios of patients were analyzed to evaluate their diagnostic values for PCBM.RESULTS The difference in general information of the patients was not obvious,showing comparability.The two methods showed no visible differences in negative predictive value and sensitivity for patients with PCBM,but had great differences in positive predictive value and specificity(P<0.05).The PSA/fPSA ratio of patients with PC in the Exp group was lower than those with BPLs,and patients with PCBM had a much lower PSA/fPSA ratio than those without PC(P<0.05).The results confirmed that the combined use of 99mTc-MDP SPECT/CT imaging and serum PSA/fPSA ratio achieved a detection rate of 95%for PCBM.CONCLUSION The combination of 99mTc-MDP SPECT/CT and PSA/fPSA ratio is accurate and reliable for the diagnosis of PCBM,which provides an important reference for clinical practice.

Total and free prostate-specific antigen indexes in prostate cancer screening:value and limitation for Japanese populations

Aim:To assess the efficacy and limitation of free/total prostate-specific antigen ratio(f/tPSA)at a single institution in Japan,focusing on the avoidance of pointless prostate biopsies.Methods:In total,631 men between 44 and 93 years old(mean 69.8 years)with elevated PSA underwent power-Doppler ultrasoundgraphy-guided transrectal 10-core prostate biopsies at Niigata Cancer Center Hospital,and their histological features were investigated with total PSA (tPSA)and f/tPSA.Results:PCa was detected in 126 of 134 patients(94.3%)with tPSA of 26 ng/mL or higher.The detection rate was 59.4% for tPSA of 21-25 ng/mL,followed by 39.2% for 16-20 ng/mL,30.0% for 11-15 ng/mL, 20.0% for 4.1-10 ng/mL and 7.6% for≤4.0 ng/mL,f/tPSA of the PCa group was significantly lower than that of non-malignamt disorders in any tPSA ranges(mean 0.122 vs.0.160,P<0.001).Receiver-operating characteristics analyses showed that f/tPSA(AUC:0.664)performed more valuably than tPSA(AUC:0.559)in patients with tPSA between 3.0-10 ng/mL(P<0.01).Although f/tPSA of 0.250 for the cut-off value might miss 1.8% PCa patients,it potentially spares 9.2% of unnecessary biopsies.Conclusion:f/tPSA is more valuable compared with tPSA alone for the prediction of the occurrence of PCa.We recommend 0.250 as the cut-off value for f/tPSA in PCa screening for Asian men having so-called grey-zone tPSA.(Asian J Androl 2006 Jul;8:429-434)

Clinical application of free/total PSA ratio in the diagnosis of prostate cancer in men over 50 years of age with total PSA levels of 2.0-25.0 ng ml^(−1) in Western China

The goal of this study was to investigate the clinical application of free/total prostate-specific antigen(F/T PSA)ratio,considering the new broad serum total PSA(T-PSA)“gray zone”of 2.0–25.0 ng ml^(−1)in differential diagnosis of prostate cancer(PCa)and benign prostate diseases(BPD)in men over 50 years in Western China.A total of 1655 patients were included,528 with PCa and 1127 with BPD.Serum T-PSA,free PSA(F-PSA),and F/T PSA ratio were analyzed.Receiver operating characteristic curves were used to assess the efficiency of PSA and F/T PSA ratio.There were 47.4%of cancer patients with T-PSA of 2.0–25.0 ng ml^(−1).When T-PSA was 2.0–4.0 ng ml^(−1),4.0–10.0 ng ml^(−1),and 10.0–25.0 ng ml^(−1),the area under the curve(AUC)of F/T PSA ratio was 0.749,0.769,and 0.761,respectively.The best AUC of F/T PSA ratio was 0.811 when T-PSA was 2.0–25.0 ng ml^(−1),with a specificity of 0.732,a sensitivity of 0.788,and an optimal cutoff value of 15.5%.The AUC of F/T PSA ratio in different age groups(50–59 years,60–69 years,70–79 years,and≥80 years)was 0.767,0.806,0.815,and 0.833,respectively,and the best sensitivity(0.857)and specificity(0.802)were observed in patients over 80 years.The T-PSA trend was in accordance with the Gleason score,tumor node metastasis(TNM)stage,and American Joint Committee on Cancer prognosis group.Therefore,the F/T PSA ratio can facilitate the differential diagnosis of PCa and BPD in the broad T-PSA“gray zone”.Serum T-PSA can be a Gleason score and prognostic indicator.