Magnetic resonance imaging and morphometric histologic analysis of prostate tissue composition in predicting the clinical outcome of terazosin therapy in benign prostatic hyperplasia

Purpose: To determine whether magnetic resonance imaging (MRI) or quantitat ive color-imaged morphometric analysis (MA) of the prostate gland are relat ed to the clinical response to terazosin. Methods: Thirty-six male patients with symptomatic benign prostatic hyperpl asia (BPH) with a serum prostate-specific antigen level of 4-10 ng/mL under went MRI with body coil, transrectal prostate ultrasonography and biopsy pr ior to terazosin therapy. For MRI-determined stromal and non-stromal BPH, t he ratio of the signal intensity of the inner gland to the obturator intern us muscle was evaluated. Histologic sections were stained with hematoxylin and eosin. The MA of the specimens was performed by Samba 2000. Results of the two techniques were interpreted according to the terazosin therapy resu lts. Results: The mean stromal percentage was 60.5 +/- 18.0%. No statistically s ignificant relationship was found between the clinical outcome of terazosin and the MRI findings. The MA results showed a significant relationship bet ween the percentage of stroma and the percent change of the peak urinary fl ow rate, but not with the percent change of the international prostate symp tom score after terazosin therapy (P < 0.05). Conclusion: Magnetic resonance imaging alone is not sufficient in predictin g the response to terazosin therapy. Morphometric analysis of BPH tissue co mposition can be used in predicting the clinical outcome of terazosin thera py but it is suitable only in patients for whom prostatic biopsy is necessa ry in order to rule out prostate cancer.