Evaluation and prediction of therapeutic response to neoadjuvant androgen deprivation therapy for prostate cancer by diffusion weighted imaging

Abstract

Objective To evaluate the effect of neoadjuvant androgen deprivation therapy (ADT)for prostate cancer on diffusion weighted imaging base on the pathological results after radical prostatectomy. Methods Medical records of 33 patients diagnosed with prostate cancer and treated with neoadjuvant androgen deprivation therapy and radical prostatectomy between January 2016 and September 2019 at Peking University First Hospital were retrospectively reviewed. Average age of patients was 67.7 (49-81) years old. All of the patients underwent prostate MRI examination before and after neoadjuvant ADT. Results Mean prostate volume after neoadjuvant ADT is 28.5 (6.25-113.76) cm3, which decreased significantly by therapy (Z=-4.458, P<0.05). Apparent diffusion coefficient (ADC) values increased significantly in tumor (1.070±0.325) vs. (0.828±0.291)×10-3mm2/s (P<0.001) and decreased in benign prostatic tissue (P<0.05). Relative changes in ADC differed significantly between low-median level ISUP group and high level ISUP group (0.315±0.173) vs. (0.164±0.224)×10-3mm2/s (P<0.05), as well as obvious reaction group and focal reaction group(0.278±0.21) vs. (0.094±0.119)×10-3mm2/s (P<0.05). Conclusions There were significant, quantitative measurable changes of ADC value in prostate cancer after neoadjuvant ADT. DWI can be used to assess the efficacy of neoadjuvant ADT for prostate cancer as well as predicting pathological features. Key words: Prostatic neoplasms; Prostate cancer; Neoadjuvant androgen deprivation therapy; Diffusion weighted imaging (DWI); Apparent diffusion coefficient (ADC)