The cutoff value of transitional zone index predicting the efficacy of dutasteride on subjective symptoms in patients with benign prostate hyperplasia.

A higher TZI was significantly associated with improvement of subjective symptoms but not uroflowmetric findings for BPH patients with 6 months of dutasteride add-on therapy along with α-1 adrenoceptor antagonists, and the predictive value of TZI for effective dutasteride add-on therapy was higher than 0.67. BPH patients using α-1 adrenoceptor antagonists with a TZI higher than 0.67 can be good candidates for add-on dutasteride therapy.