Diagnostic value of 18F-PSMA-1007 PET/CT combined with prostate specific antigen derived indicators in gray area prostate cancer.

The incidence of prostate cancer is increasing every year, and precision diagnosis and treatment can help reduce unnecessary prostate punctures for prostate cancer patients in the gray area. This study aims to investigate the diagnostic value of 18F-prostate specific membrane antigen (PSMA) imaging combined with prostate specific antigen (PSA)-derived indicators for gray zone prostate cancer.A total of 107 patients who underwent 18F-PSMA PET/CT imaging for suspicious prostate cancer with tPSA of 4 to 10 μg/L (PSA gray zone) in a hospital were retrospectively included, and were divided into a prostate cancer group and a non-prostate cancer group based on pathological findings. Patients underwent PSA testing, 18F-PSMA, and abdominal ultrasound, and age, tPSA, fPSA, f/tPSA, prostate volume, PSA density (PSAD), maximum standardized uptake value (SUVmax), and molecular imaging prostate specific membrane antigen (miPSMA) score were compared between the 2 groups. Multivariate logistic regression was used to analyze the influencing factors the diagnosis of gray zone prostate cancer. Receiver operating characteristic (ROC) curves were constructed to evaluate the efficacy of PSAD and SUVmax alone and in combination in diagnosing gray zone prostate cancer.The volume of the prostate cancer group [42.00(34.00, 58.00) cm3 vs 49.00(41.27, 60.41) cm3] was smaller than that of the non-prostate cancer group (Z=-2.376, P=0.017), and the PSAD [(0.18±0.06) μg/(L·cm3) vs 0.15±0.05 μg/(L·cm3)] and SUVmax [18.63(8.03, 28.57) vs 9.33(5.90, 13.52)] were higher than those in the non-prostate cancer group (both P<0.05). The percentage of miPSMA score ≥2 in the prostate cancer group was higher than that in the non-prostate cancer group (χ2=40.987, P<0.001). PSAD (OR=22.154, 95% CI 1.430 to 873.751, P=0.042) and SUVmax (OR=1.301, 95% CI 1.034 to 1.678, P=0.009) were independent influential factors for the diagnosis of prostate cancer in the gray zone. The optimal cut-off values of PSAD and SUVmax were 0.22 μg/(L·cm3) and 8.02, respectively, and the AUCs for the diagnosis of prostate cancer in the gray zone alone and in combination were 0.628 (95% CI 0.530 to 0.720, P<0.05) and 0.806 (95% CI 0.718 to 0.876, P<0.05), 0.847 (95% CI 0.765 to 0.910, P<0.05), with sensitivities of 41.03%, 76.92%, and 74.36% and specificities of 79.41%, 89.71%, and 92.65%, respectively.PSAD and SUVmax are increased in patients with gray zone prostate cancer, and the combination of PSAD and SUVmax is of high value in diagnosing gray zone prostate cancer.目的: 前列腺癌的发病率逐年上升，精准诊疗可以帮助灰区前列腺癌患者减少不必要的前列腺穿刺。本研究旨在探讨18F-前列腺特异性膜抗原(prostate specific membrane antigen，PSMA)显像联合前列腺特异性抗原(prostate specific antigen，PSA)衍生指标对灰区前列腺癌的诊断价值。方法: 回顾性纳入甘肃省人民医院107例因总前列腺特异性抗原(total prostate specific antigen，tPSA)为4~10 μg/L(PSA灰区)的可疑性前列腺癌行18F-PSMA PET/CT显像的患者，根据病理学检查结果分为前列腺癌组和非前列腺癌组。患者均接受PSA检测、18F-PSMA及腹部超声检查，比较2组年龄、tPSA、游离PSA(free PSA，fPSA)、f/tPSA、前列腺体积、PSA密度(PSA density，PSAD)、最大标准化摄取值(maximum standardized uptake value，SUVmax)、分子成像前列腺特异性膜抗原(molecular imaging prostate specific membrane antigen，miPSMA)评分。采用多因素logistic回归分析诊断灰区前列腺癌的影响因素。构建受试者操作特征(receiver operating characteristic，ROC)曲线，评估PSAD、SUVmax单独及联合诊断灰区前列腺癌的效能。结果: 前列腺癌组体积[42.00(34.00，58.00) cm3 vs 49.00(41.27，60.41) cm3]小于非前列腺癌组(Z=-2.376，P=0.017)，PSAD[(0.18±0.06) μg/(L·cm3) vs (0.15±0.05) μg/(L·cm3)]和SUVmax[18.63(8.03，28.57) vs 9.33(5.90，13.52)]均高于非前列腺癌组(均P<0.05)。前列腺癌组miPSMA评分≥2的比例高于非前列腺癌组(χ2=40.987，P<0.001)。PSAD(OR=22.154，95% CI 1.430~873.751，P=0.042)和SUVmax(OR=1.301，95% CI 1.034~1.678，P=0.009)是诊断灰区前列腺癌的独立影响因素。PSAD和SUVmax的最佳截断值分别为0.22 μg/(L·cm3)和8.02，单独PSAD、SUVmax及PSAD和SUVmax联合诊断灰区前列腺癌的AUC分别为0.628(95% CI 0.530~0.720)、0.806(95% CI 0.718~0.876)、0.847(95% CI 0.765~0.910)(均P<0.05)，灵敏度分别为41.03%、76.92%、74.36%，特异度分别为79.41%、89.71%、92.65%。结论: 灰区前列腺癌患者PSAD、SUVmax增高，PSAD和SUVmax联合诊断灰区前列腺癌的价值较高。.