Effects of Medication with Dutasteride on Detection of Prostate Cancer in Patients with Serum Prostate-specific Antigen Level of 4~10 ng/ml

Shin, Jun Shik; Cho, Sung Ryong

Abstract

Purpose: We assessed the effects of medication with dutasteride on serum prostate-specific antigen (PSA), PSA density (PSAD) and prostate volume to avoid unnecessary biopsies.
Materials and Methods
Between 2005 and 2007 patients with serum PSA level of 4~10 ng/ml were recruited in this prospective study. Patients were treated with 0.5 mg of dutasteride once daily for 3 months. PSA, PSAD and prostate volume were measured at baseline and at the end of treatment. The patients with a high PSA level (> or =4 ng/ml) after medication with dutasteride had a prostate biopsy. The patients were divided as group I (prostate cancer; n=29) and group II (benign disease; n=55). We compared the changes of serum PSA, PSAD, and prostate volume change between two groups.
Results
In group I, PSA, PSAD and prostate volume decreased from baseline means of 8.16 ng/ml, 0.23 ng/ml/cm3 and 46.81 cc to 5.69 ng/ml, 0.18 ng/ml/cm3 and 40.41 cc. The difference in PSA, PSAD and prostate volume was -0.2%, -2.1% and -3.6% for group I. On the contrary, in group II, PSA, PSAD and prostate volume decreased from baseline means of 7.65 ng/ml, 0.16 ng/ml/cm3 and 56.48 cc to 4.48 ng/ml, 0.11 ng/ml/cm3 and 51.35 cc. The difference in PSA, PSAD and prostate volume was -41.4%, -33.3% and -9.1% for group II. When 4.83 ng/ml and 0.15 ng/ml/cm3 were chosen as the PSA and PSAD cutoff levels after treatment with dutasteride, unnecessary biopsies could be avoided effectively.
Conclusions
These data suggest that the magnitude of changes in serum PSA and PSAD after 3 months of dutasteride challenge could be useful to avoid unnecessary prostate biopsies in patients with elevated PSA level.