Objective To quantitatively analyze and testify the diagnostic value of combined MRS and DWI for prostate cancer based on sextant localization.Methods Patients who underwent prostate MR examinations in our hospital had MRS and DWI scanning in addition to conventional MRI.The(choline+creatine)/citrate(CC/C)value in each measurable voxel and the minimal ADC value(ADC_(mini))in each sextant were measured.Taking CC/C of no less than 0.911 as the cutoff value for prostate cancer,the ratios of positive voxel(PVR)in sextants were calculated.The selected patients were divided into 2 groups according to the date of examination,for the quantitative analysis and the verification respectively.Group 1 was from Feb,2006 to Dec,2006,and group 2 from Jan,2007 to Jul,2007.The diagnostic efficacy of PVR,ADC_(mini) and their combination was tested by ROC analysis.Results There were 40 patients in group 1 and group 2 respectively for the linear discrimination of the cluster analysis,including 20 patients with prostate cancer and 20 patients without prostate cancer.The linear discrimination equation calculated from group 1 was 'D=3.264×ADC_(mini)-0.205×PVR-4.407'.The areas under curve(Az)of ROC for PVR,ADC_(mini) and D were 0.769,0.910 and 0.909,respectively.In group 2,the Az of ROC for PVR,ADC_(mini) and D were 0.838,0.912 and 0.915,respectively.There were no statistical difference between ADC_(mini)-alone and D in both groups(X~2=0.32 and 1.50,P＞0.05).Conclusions Quantitative prostate DWI had higher diagnostic value than MRS.The combined use of MRS and DWI was not superior to the DWI-alone in the diagnostic efficacy of prostate cancer.

ObjectiveTo determine if the three-dimensional proton magnetic resonance spectroscopic(MRS) imaging helps in diagnosing metastasis ofprostate cancer(Pca).MethodsSixty-five patients with biopsy proven Pca were recruited and divided into two groups:group 1 with metastasis(bone and/or lymph node metastasis)(n=34)and Group 2 without metastasis(n=31).Voxels were placed on cancerous area in peripheral zone and the ratios of(Cho+Cre)/Cit were measured.The mean ratio in each patient was calculated and ROC curve was drawn to determine the optimal operating point(OOP)for the prediction of Pca metastasis by the metabolite ratio.ResultsThe mean ratio of(Cho+Cre)/Cit in cancerous area of Pca without metastasis was 1.3 ±0.5,whereas that of Pca with metastasis was 2.2±0.6.Statistically significant difference existed between the two groups(t=6.38,P＜0.05).According to the ROC analysis,the OOP was determined and interpreted at 1.53 with higher sensitivity and specificity.If Pca with metastasis was predicted as whose the mean ratio of(Cho+Cre)/Cit in cancerous area larger than 1.53,the sensitivity,specificity and accuracy for metastasis determination were 94.12%(32/34),67.74%(21/31),and 81.54%(53/65)respectively.Conclusion MRS may be a useful noninvasive method to predict the metastasis of Pca.

Objective To evaluate three-dimensional reconstruction of MRI images in diagnosis and therapy of prostate cancer. Methods Twenty-eight patients with proven prostate cancers were recruited in this study. Seventeen of them were diagnosed as having prostate cancer according to the ultrasound guided systemic biopsy. Their MR examinations showed fourteen lesions in the peripheral zone and three in the central gland of the prostate. The other eleven patients underwent MR examination after a period of treatment, including endocrinetherapy and brachytherapy. Using endorectal coil, a series of T2-weighted images were acquired on the axial plane. These source images were processed by 3D-Doctor software to reconstruct into three-dimensional images. Results In the fourteen patients with peripheral zone cancer, reconstruction images could display the 3D regions of cancer and the involvement of capsular. The outspread of central gland and the compression of peripheral zone in patients with central gland cancer could be revealed in the same way. The volumetric changes of the lesion and the prostate after endocrinetherapy could also be perceived through these 3D images. Similarly, radioactive seeds were revealed in a spatial manner that could be easily evaluated. Conclusion Three-dimensional reconstruction images were obtained in all patients. They were able to provide stereotyped information about the lesions and their surrounding tissues. MRI three-dimensional reconstruction can be an adjunctive tool in the evaluation of prostate lesions.

Objective To evaluate the therapeutic effect of endocrine for prostate cancer with bone metastases with MR diffusion-weighted imaging (DWI). Methods Forty patients with bone metastases from prostate cancer were examined with DWI. Seventeen patients underwent endocrine therapy were recruited as the test group, the other 23 were regarded as the control group. There was no relapse of the metastases according to clinical diagnosis in the test group. DWI sequences were based on steady-state free precession with b value (800 s/mm~2). After identifying the metastasis according to the T1WI and T2WI, ROIs were marked at the metastases, normal muscle, normal bone and bladder on DWI, and the ADC values of the ROIs were calculated respectively. Non-parameter two independent samples test was applicated to compare the ADC values of the metastases between the two groups.Results ADC values of the bone metastases were (1.10±0.50)×10~(-3)mm~2/s in the test group and (1.12±0.30) ×10~-3mm~2/s in the control group (P>0.05).Conclusion MR DWI shows no help in evaluating the therapeutic effect of endocrine for prostate cancer with bone metastases.

40 years, old group) without prostate diseases, underwent MRI and MRS examinations. The peripheral zone (PZ) and central gland (CG) of the prostate were distinctly demonstrated on MRI, the right and left side of PZ and CG were divided into bottom, middle and tip regions,totally 12 samples were obtained from each case. The levels of (Cho+Cre)/Cit ratios were calculated on the basis of the MRS metabolic map. Results ①The mean level of (Cho+Cre)/Cit ratios in PZs and CGs of different regions in young group and old group was not significantly different. Statistically significant variation of the (Cho+Cre)/Cit ratio in PZs and CGs in the two groups was detected. ②The mean level of (Cho+Cre)/Cit ratios of PZs between young group and old group was not significantly different. Only Statistically significant variation of (Cho+Cre)/Cit ratios in CGs between two groups was detected. Conclusion The normal levels of prostatic metabolites fluctuate dramatically among individuals. There is metabolic difference between the peripheral and central zone and that of young and old group.

Objective To investigate MRI characteristics of recurrent prostate cancer after endocrinotherapy.Methods Recurrent prostate cancer after endocrinotherapy was diagnosed clinically in 10 cases.MRI examinations were performed before and after recurrence of tumors.T_2 signal intensity and morphological changes of the prostate,involvement of pelvic tissues,metastasis of bone and lymph metastasiswere analyzed.Results The prostates enlarged in 7 patients after recurrence and maintained the same size in the other three.The pelvictissues,including seminal vesicle,bladder,rectal and obturator internus,were involved in 7 patients after recurrence.Metastasis of bone and lymph node progressed in 7 and 9 patients,respectively,but T_2 signal differences were unremarkable between recurrent regions and otherregions.Conclusion MRI examination can provide sufficient radiologic information in the diagnosis of recurrence of prostate cancer afterendocrinotherapy.

0.05) except the patient’s age(P=0.00).Conclusion Follow-up of patients with non-tumoral lesions in prostate gland with MR imaging usually does not give useful informations in addition to the first MR examination.

Objective To quantitatively analyze the ADC values of different types of benign prostatic hyperplasia(BPH) comparatively with ADC values of prostatic carcinoma(Pca).Methods Seventeen cases of BPH(mean age 69.1 years?4.3 years,ranged from 62 to 77 years) underwent transurethral resection of prostate(TURP) were scanned with the sequence of DWI.DWI(b-values = 0 s/mm2and 800 s/mm2) was performed at 1.5-T system.The hyperplasia tissues resected from central gland were divided into two types pathologically: glandular BPH and stromal BPH.According to the pathological results,ROIs were placed on central gland and the ADC values of two types of BPH were measured.In addition,fifteen patients with biopsy-proved Pca were evaluated and the ADC values of Pca regions were measured.Results The mean ADC values of glandular BPH,stromal BPH and Pca were(1.80?0.20)?10-3 mm2/s,(1.56?0.18)?10-3 mm2/s and(1.27?0.21)?10-3 mm2/s,respectively.Statistically significant difference(F=47.366,P

Objective To investigate the changes of apparent diffusion coefficient(ADC) values after endocrinotherapy in cancerous and noncancerous regions of prostate peripheral zone.Methods 28 patients with prostate cancer proved by pathology were retrospectively evaluated in this study.The prostate peripheral zone was divided into two regions(cancerous and noncancerous regions).All patients were examined by single-shot diffusion-weighted echo-planar imaging before and after 3~6 months endocrinotherapy.ADC values of noncancerous and cancerous regions in peripheral zone were calculated and statistical analysis was performed on the data by applying either paired or independent t-test.Results Before treatment, the average ADC values in noncancerous ( n=107 ) and cancerous ( n=61 ) regions were (2.21?0.61)?10-3 mm2/s and (1.65?0.46)?10-3mm2/s, respectively, and statistic significant difference could be detected between them (t=4.36, P=0.039, independent t-test). After 3~6 months treatment, the ADC values in noncancerous and cancerous regions decreased to(1.33?0.48)?10-3 mm2/s and (1.28?0.53)?10-3mm2/s, respectively, significantly lower than those before treatment(t=5.28, P=0.024 and t=7.39, P=0.015, paired t-test),but no significant difference between noncancerous and cancerous regions was detected after endocrinotherapy (t=0.58, P=0.639, independent t-test). Conclusion After endocrinotherapy, the ADC value of cancerous and noncancerous prostate tissues both decreased. This change was more significant in noncancerous tissue and the difference of ADC values between them diminished after endocrinotherapy.

0.05,Friedman Test).When b-value increased from 300 s/mm2 up to 500 s/mm2 and 800 s/mm2,the decreased rates of ADC value were 14% and 21% respectively in carcinous regions,5% and 11% respectively in non-carcinous regions respectively.Conclusion The ADC values are different when b-values changed in both prostatic non-carcinous and carcinous regions,but the difference of ADC between the non-carcinous and carcinous tissues seems to be stable in spite of the change of b-value(range 300-800 s/mm2).