Prostate Cancer: assessing the effects of androgen-deprivation therapy using quantitative diffusion-weighted and dynamic contrast-enhanced MRI

Abstract

Purpose: To investigate the effects of androgen-deprivation therapy (ADT) on MRI parameters and evaluate their associations with treatment response measures.

Materials and methods: The study included 30 men with histopathologically confirmed prostate cancer who underwent MRI before and after initiation of ADT. Thirty-four tumours were volumetrically assessed on DW-MRI (n = 32) and DCE-MRI (n = 18), along with regions of interest in benign prostatic tissue, to calculate apparent diffusion coefficient (ADC) and transfer constant (K(trans)) values. Changes in MRI parameters and correlations with clinical parameters (change in prostate-specific antigen [PSA], treatment duration, PSA nadir) were assessed.

Results: Prostate volume and PSA values decreased significantly with therapy (p < 0.001). ADC values increased significantly in tumours and decreased in benign prostatic tissue (p < 0.05). Relative changes in ADC and absolute post-therapeutic ADC values differed significantly between tumour and benign tissue (p < 0.001). K(trans) decreased significantly only in tumours (p < 0.001); relative K(trans) changes and post-therapeutic values were not significantly different between tumour and benign tissue. The relative change in tumour ADC correlated significantly with PSA decrease. No changes were associated with treatment duration or PSA nadir.

Conclusions: Multi-parametric MRI shows significant measurable changes in tumour and benign prostate caused by ADT and may help in monitoring treatment response.

Key points: • Androgen-deprivation therapy caused changes of ADC, K (trans) in tumour and benign prostate. • Prostate volume and PSA values decreased significantly with therapy. • ADC values may be helpful for monitoring treatment response.

Figures

Fig. 1

a-f: Sixty-eight-year-old man with histopathologically-proven prostate cancer (Gleason score 4+4) who had MRI examinations before (a-c) and after the start (d-f) of androgen-deprivation therapy: (a/d) T2-weighted images, (b/e) ADC maps (b = 1000 s/mm2), (c/f) T1-weighted dynamic contrast-enhanced MR images.

Fig. 1

a-f: Sixty-eight-year-old man with histopathologically-proven prostate cancer (Gleason score 4+4) who had MRI examinations before (a-c) and after the start (d-f) of androgen-deprivation therapy: (a/d) T2-weighted images, (b/e) ADC maps (b = 1000 s/mm2), (c/f) T1-weighted dynamic contrast-enhanced MR images.

Fig. 1

a-f: Sixty-eight-year-old man with histopathologically-proven prostate cancer (Gleason score 4+4) who had MRI examinations before (a-c) and after the start (d-f) of androgen-deprivation therapy: (a/d) T2-weighted images, (b/e) ADC maps (b = 1000 s/mm2), (c/f) T1-weighted dynamic contrast-enhanced MR images.

Fig. 1

a-f: Sixty-eight-year-old man with histopathologically-proven prostate cancer (Gleason score 4+4) who had MRI examinations before (a-c) and after the start (d-f) of androgen-deprivation therapy: (a/d) T2-weighted images, (b/e) ADC maps (b = 1000 s/mm2), (c/f) T1-weighted dynamic contrast-enhanced MR images.

Fig. 1

a-f: Sixty-eight-year-old man with histopathologically-proven prostate cancer (Gleason score 4+4) who had MRI examinations before (a-c) and after the start (d-f) of androgen-deprivation therapy: (a/d) T2-weighted images, (b/e) ADC maps (b = 1000 s/mm2), (c/f) T1-weighted dynamic contrast-enhanced MR images.

Fig. 1

a-f: Sixty-eight-year-old man with histopathologically-proven prostate cancer (Gleason score 4+4) who had MRI examinations before (a-c) and after the start (d-f) of androgen-deprivation therapy: (a/d) T2-weighted images, (b/e) ADC maps (b = 1000 s/mm2), (c/f) T1-weighted dynamic contrast-enhanced MR images.

Fig. 2

a/b: Plots for ADC (mm2/s) and Ktrans (min−1) values before (pre) and after the start (post) of androgen-deprivation therapy for each individual patient, stratified by peripheral zone (PZ), transition zone (TZ) and tumour.

Fig. 2

a/b: Plots for ADC (mm2/s) and Ktrans (min−1) values before (pre) and after the start (post) of androgen-deprivation therapy for each individual patient, stratified by peripheral zone (PZ), transition zone (TZ) and tumour.