前列腺特异抗原＜4μg/L前列腺癌经直肠超声引导穿刺活检的临床研究

目的 评价经直肠超声(TRUS)引导下前列腺穿刺活检对前列腺特异抗原(PSA)＜4μg/L前列腺癌(PCA)诊断的临床价值,借以探讨提高PSA＜4μg/L的PCA诊断率的方法.方法 选取59例PSA＜4μg/L怀疑PCA的患者进行TRUS引导下前列腺多点穿刺活检.分析其TRUS声像图特点尤其对前列腺内结节声像特点进行总结,并比较PCA与非PCA组患者间的PSA、前列腺特异抗原密度(PSAD)、前列腺游离抗原与总前列腺抗原比值(F/T)、前列腺体积(PV),进一步分析PSAD、F/T的各阈值范围内对PCA诊断的敏感性及特异性.结果 59例受检者中经病理证实PCA 16例,检出率为27%,12例PCA患者声像图检查显示前列腺结节性病变,均分布于外腺,且血流增加较良性病变及癌前病变高.PCA组与非PCA组间的PSA、PSAD、F/T、PV差异均有统计学意义.将PSAD阈值设为0.09μg/L2时有较高的敏感性及特异性,F/T值设为0.20时有较高的敏感性及特异性,但不及PSAD有优势.结论 TRUS前列腺穿刺活检是确诊PSA＜4 μg/L PCA的最有效方法之一,结合TRUS声像图特点及PSA修正方法可进一步提高PCA的检出率.

The clinical study of transrectal ultrasound guided biopsies of the prostate cancer with PSA level less than 4 μg/L

Objective To evaluate the clinical value of transrectal ultrasound(TRUS)guided biopsies of the prostate cancer(PCA)with serum prostate specific antigen(PSA)level less than 4 μg/L.Methods Fifty-nine patients suspected PCA were underwent TRUS guided-biopsy.The ultrasonographic features of lesions and prostate gland were observed.The PSA,PSA density(PSAD),F/T(free/total PSA ratio),prostatic volume(PV)were compared between PCA group and non-PCA group,and further analyzed the sensitivity and specificity of PSAD and F/T at different thresholds for PCA diagnosis.Results In 59 patients,16 were proved to be cancer by pathological examination,the positive detection rate was 27%.In these 16 patients,12 had lesions on ultrasound,which locatqed in outer gland.The rich vascularity was observed in PCA more than in benign and precancerous lesion.There were statistical significant differences in PSA,PSAD,F/T,PV between PCA and non-PCA groups.When selecting threshold of PSAD and F/T were 0.09 and 0.20,respectively,there were the highest diagnostic specificity and sensitivity.The diagnostic specificity and sensitivity of PSAD were higher than those of F/T.Conclusions TRUS guided biopsies of the prostate is one of the most efficient methods for detection of PCA with PSA level less than 4μg/L.Combining TRUS features with PSA parameters can further increase positive detection rate of PCA.