Korean J Urol.  2007 Dec;48(12):1242-1246. 10.4111/kju.2007.48.12.1242.

The Influence of Prostate Volume on the Serum Prostate-specific Antigen Levels and the Percentage of the Free Prostate-specific Antigen Levels during Finasteride Medication

• Lee KH
• Cho SY
• Cho IR

• KMID: 1990147
• DOI: http://doi.org/10.4111/kju.2007.48.12.1242

Abstract

PURPOSE: Little is known about the effect of the prostate volume on the free prostate-specific antigen(PSA) level and the percent of the free PSA level with administering finasteride medication. We studied the effect of finasteride therapy on the levels of serum PSA, the free PSA and the percentage of free PSA according to the prostate volume.
MATERIALS AND METHODS
Patients with lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia(BPH) and who were over 50 years old were treated with finasteride 5mg for 6 months. Male patients with a PSA level between 3.5ng/ml and 15ng/ml were included and these patients were biopsied. alpha-blockers were prescribed to treat them for LUTS. The serum levels of the total PSA and free PSA were measured at baseline and after 6 months. We analyzed the changes of PSA and fre-PSA before and after finasteride administration. We also analyzed the patients' changes based on the prostate volume.
RESULTS
The analysis included 44 patients with a mean age of 71.7 years, a baseline prostate volume of 56.0cc and a baseline total PSA level of 6.74ng/ml. The total PSA and free PSA levels declined from 6.74ng/ml and 2.57ng/ml at baseline to 3.83ng/ml and 1.45ng/ml after 6 months of treatment, respectively(p<0.05). The mean percent free PSA was not significantly altered by finasteride treatment. Those patients with a small prostate volume showed larger decrements in the PSA and free PSA than did the patients with a large prostate volume, but the prostate volume at baseline did not affect the percent free PSA levels.
CONCLUSIONS
It is debatable that the application of the 'double's rule' without considering the volume of the prostate is appropriate for the treatment of patients who are taking finasteride medication.

Keyword

Prostate-specific antigen; Prostatic hyperplasia; Finasteride

MeSH Terms

Finasteride*
Humans
Lower Urinary Tract Symptoms
Male
Middle Aged
Prostate*
Prostate-Specific Antigen*
Prostatic Hyperplasia
Finasteride
Prostate-Specific Antigen

Reference

1. Kim JG, Cho IR, Park SS. Prostate specific antigen velocity in healthy men with Initial PSA levels of 4.0ng/ml or less. Korean J Urol. 2001. 42:942–947.

2. Pannek J, Marks LS, Pearson JD, Rittenhouse HG, Chan DW, Shery ED, et al. Influence of finasteride on free and total serum prostate specific antigen levels in men with benign prostatic hyperplasia. J Urol. 1998. 159:449–453.

3. Lowe FC, McConnell JD, Hudson PB, Romas NA, Boake R, Lieber M, et al. Long-term 6-year experience with finasteride in patients with benign prostatic hyperplasia. Urology. 2003. 61:791–796.

4. Guess HA, Heyse JF, Gormley GJ, Stoner E, Oesterling JE. Effect of finasteride on serum PSA concentration in men with benign prostatic hyperplasia. Results from the North American phase III clinical trial. Urol Clin North Am. 1993. 20:627–636.

5. Cho SH, Lee SK. The experience with combination of finasteride and tamsulosin on benign prostatic hyperplasia. Korean J Urol. 2003. 44:1110–1115.

6. Soh BH, Lee JS, Chung BH. The changing pattern of serum prostate specific antigen in patients with benign prostatic hyperplasia after combined treatment with finasteride and α-blockers: the 3 year follow-up data. Korean J Urol. 2006. 47:372–376.

7. Kim DS, Roh SH, Lee DH. The effect of transrectal ultrasonography and digital rectal examination on serum free prostate-specific antigen and percentage of free prostate-specific antigen levels. Korean J Urol. 2003. 44:968–972.

8. Kim DY, Kwak C, Lee SB, Park EC, Jeong H, Lee SE. The factors influencing the percentage of free serum prostate specific antigen levels in men without clinically detectable prostate cancer. Korean J Urol. 2000. 41:718–724.

9. Catalona WJ, Beiser JA, Smith DS. Serum free prostate specific antigen and prostate specific antigen density measurement for predicting cancer in men with prior negative prostatic biopsies. J Urol. 1997. 158:2162–2167.

10. Lee YK, Kim HS, Oh TH. The effect of age, prostate volume and total PSA on percent free PSA in men with benign prostatic disease. Korean J Urol. 1999. 40:997–1002.

11. Matzkin H, Barak M, Braf Z. Effect of finasteride on free and total serum prostate-specific antigen in men with benign prostatic hyperplasia. Br J Urol. 1996. 78:405–408.

12. Hong JE, Hong SJ. Changes in prostate volume, transitional zone volume and PSA after cessation of the finasteride. Korean J Urol. 1999. 40:1519–1524.

13. Espana F, Martinez M, Royo M, Estelles A, Alapont JM, Navarro S, et al. Changes in molecular forms of prostate-specific antigen during treatment with finasteride. Br J Urol. 2002. 90:672–677.

14. Brawer MK, Lin DW, Williford WO, Jones K, Lepor H. Effect of finasteride and/or terazosin on serum PSA: reults of VA Cooperative Study #359. Prostate. 1999. 39:234–239.