Single-Center Clinical Study Of MR-DWI Assisted Ultrasound-Guided Prostate Biopsy

Background:Prostate cancer(PCa)is one of the most common malignant tumors in the male genitourinary system,which is derived from the prostate epithelial cells.Epidemiological statistics showed that the incidence of prostate cancer is already the second highest in male malignant tumors around the world.In developed countries such as European countries and the United States,the incidence of prostate cancer has ranked first in male malignancies,mortality ranked second for several years.Some recognized researched show that the incidence of prostate cancer is closely related with the patient's age,lifestyle,genetic susceptibility and ethnicity.In addition,along with the social development,improved living standards,lifestyle changes,increasing population aging,the popularity of health knowledge,and improved medical level,the incidence and detection rate of male prostate cancer also showed a significant upward trend in China.The filtering of prostate cancer mainly depends on prostate specific antigen(PSA),directeral rectal examination(DRE),ultrasound,nuclear magnetic resonance(MR),etc.PSA is currently one of the most important clinical indicators of filtering for prostate cancer,with high sensitivity,low specificity.However,PSA is susceptible to prostatitis,urinary retention,taking drugs and other effects,easily leading to misdiagnosis or missed diagnosis and make non-Prostate cancer patients received unnecessary biopsy repeatedly.Transrectal ultrasound(TRUS)-guided prostate biopsy is a commonly recognized as diagnostic method for prostate cancer.Some study found that the needle number of prostate biopsy should be no less than 6 needles,and with the enlargement of the prostate volume,the number of puncture needles need to be increased,but the positive rate of puncture did not increase significantly.In order to improve the accuracy of prostate biopsy,some scholars put forwards 10,11,12,13,14,16,18 needles puncture method,some scholars even proposed more than 20 needles saturated puncture,which the positive rate reached 44.6%-51.7%.While improving the positive rate,the complications rate got increased,such as postoperative bleeding,infection and so on.Transrectal ultrasound-guided prostate biopsy owns the advantages of convenient and high safety.However,the low resolution of the anatomic structure of the ultrasound image cannot accurately show the location of the lesion in the early stage and the small tumor,which results in the missed diagnosis and delaying the best time to treat prostate cancer.With the development of imaging technology,CT,MR,PET/CT have been used for the diagnosis of prostate cancer.Compared with CT,PET/CT,MR can clearly show the micro structure of the prostate.With the development of multi-parameter MR,especially with the magnetic resonance Diffusion weighted Imaging(MR-DWI)and apparent diffusion coefficients(ADC),detection rate of tumor has been significantly improved.There is no comparison between routine 15-needle system biopsy and MR-DWI-assisted ultrasound-guided 15-needle systematic biopsy and MR-TRUS fusion targeted prostate biopsy and how to increase the detection rate of prostate cancer in patients with DWI diffusion unrestricted.The study will be a preliminary exploration.Objective:Preliminarily evaluate the clinical value of MR-DWI-assisted ultrasound-guided 15+x needle biopsy and MRI/TRUS fusion targete prostate biopsy in the diagnosis of prostate cancer and how to improve the detection rate of DWI diffusion-limited and unrestricted prostate cancer.Methods:1.We retrospectively analyzed the clinical data of 215 patients who underwent transrectal ultrasound-guided prostate biopsy and all of those patients took the examination of MR-DWI and PSA>4ng/ml from January 2012 to December 2017 in Zhujiang Hospital,Southern Medical University.At the same time,we conducted correlation analysis with the 560 conventional biopsy studies without MR examination in our department.2.Randomly selected 70 patients with PSA>4ng/ml and MR-DWI diffusion limited from August 2017 to January 2018.35 patients performed MR-TRUS fusion targeted prostate biopsy,as the experimental group(TB),and other 35 patients performed conventional systematic biopsy as a control group(SB),and the results were analyzed.Results:This study showed that the detection rate of prostate cancer with MR-DWI-assisted ultrasound and conventional systematic biopsy was 49.7%and 38.2%,and the difference was statistically significant(p<0.05).When 10ng/ml?PSA?20ng/ml,the detection rates of MR-DWI-assisted ultrasound and conventional systematic biopsy were 41.8%and 30.9%,and the difference was statistically significant(p<0.05).When 20 ng/ml ? PSA,the detection rates of MR-DWI-assisted ultrasound and conventional systematic biopsy were 78.5%and 56.6%,and the difference was statistically significant(p<0.05).When 30 mlprostate volume ? 80 ml,the detection rate of DWI(+)group conventional systematic biopsy group was 54.3%,36.7%.There was no statistically significant difference in the Gleason score and the graded grouping between the biopsy pathological results and the pathological results after radical resection(p>0.05).The area under the curve(ROC-AUC)for PSA,fPSA,f/tPSA,and PSAD were:0.829,0.760,0.624,and 0.868,and the area under the curve for PSAD was higher than PSA,fPSA,and f/tPSA.The best cutoff point,specificity,and sensitivity of PSAD were 0.2,87.6%,and 60.2%.For DWI(+)patients,the detection rates of prostate cancer with PSAD?0.2 and PSAD<0.2 were 69.4%and 11.3%,with a statistically significant difference(p<0.01).In DWI(-)patients,the detection rates of prostate cancer with PSAD?0.2 and PSAD<0.2 were 32.3%and 6.3%,with no statistically significant difference(p>0.05).The detection rates of MR-TRUS fusion targeted prostate biopsy and systematic prostate biopsy were 54.3%and 37.1%,and the difference was not statistically significant(p>0.05).The number of targeted biopsy and systematic biopsy needles was(5.5±2.0)and(15.0±0.4),the difference was statistically significant(p<0.01).In 19 patients with prostate cancer diagnosed by targeted biopsy,the number of targeted biopsy needles was 114,and the number of positive needles was 68 and the positive rate was 60.0%.Conclusion:1.MR-DWI assisted ultrasound-guided systematic prostate biopsy can increase the detection rate of prostate cancer.In this experiment,we observed that the detection rate of DWI(+)patients with PSA>10 ng/ml and 30 ml?prostate volume?80 ml was significantly higher than that obtained by simple ultrasound-guided puncture.2.PS AD can identify prostate cancer and benign prostatic hyperplasia more accurately than PSA,fPSA,f/tPSA.In MR-DWI patients with limited diffusion,the detection rate of prostate cancer with PS AD ? 0.2 was significantly higher than that with PSAD<0.2.In DWI(-)patients,the detection rate of prostate cancer with PSAD?0.2 was higher than PSAD<0.2.3.MRI-ultrasound fusion prostate-targeted biopsy can significantly increase the detection rate of prostate cancer,accurately locate the suspicious lesion sites,puncture more accurately,reduce the number of puncture needles and trauma.