Post-treatment PSA </= 0.2 ng/mL Defines Disease Freedom After Radiotherapy for Prostate Cancer Using Modern Techniques
Frank A, Critz, W. Hamilton Williams, Clinton T. Holladay, et al
Abramson Cancer Center of the University of Pennsylvania
Last Modified: November 1, 2001
Reviewers: Li Liu, M.D.
Source: Urology, Volume 54:968-971, (December) 1999.
Since serum prostate specific antigen (PSA) testing became widely available for clinical use in the late 1980s, it has become a conventional means of monitoring treatment outcome after radiotherapy (RT) for patients with prostate cancer. Physicians have used post-RT PSA levels to document treatment failure because a rising PSA profile has been associated consistently with subsequent clinical failure (Journal of Urology 1993 Mar;149(3):519-22). In this study, the researchers reported PSA nadir achieved in men treated with radiotherapy.
Materials and Methods
A total of 453 men who underwent prostate seed implant plus external beam radiation for prostate cancer were included. The minimum follow-up was 5 years (range 5-15 years).
- 97% of the men with stage T1-2 Nx prostate cancer achieved a PSA nadir of 0.2 ng/mL or less.
- In the group as a whole, 92% of men who achieved PSA nadir of 0.2 ng/mL or less had a nonrising PSA level 10 years after treatment.
- By comparison, the PSA level rose in all men whose PSA nadir was greater than 1.0 ng/mL.
According to this study, the vast majority of men who achieve a PSA nadir of 0.2 ng/mL or less after irradiation for prostate cancer can expect to remain disease free. Individual pretreatment characteristics should be considered when attempting to estimate the likelihood of cure at a given interval after completing RT. Patients with more favorable pretreatment characteristics (lower PSA levels and Gleason scores) may require longer follow-up than those with less favorable characteristics to achieve the same certainty of cure.