Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Controlled Clinical Trial
. 2007 Jul 1;68(3):682-9.
doi: 10.1016/j.ijrobp.2007.01.008. Epub 2007 Mar 29.

What dose of external-beam radiation is high enough for prostate cancer?

Affiliations
Controlled Clinical Trial

What dose of external-beam radiation is high enough for prostate cancer?

Thomas N Eade et al. Int J Radiat Oncol Biol Phys. .

Abstract

Purpose: To quantify the radiotherapy dose-response of prostate cancer, adjusted for prognostic factors in a mature cohort of men treated relatively uniformly at a single institution.

Patients and methods: The study cohort consisted of 1,530 men treated with three-dimensional conformal external-beam radiotherapy between 1989 and 2002. Patients were divided into four isocenter dose groups: <70 Gy (n = 43), 70-74.9 Gy (n = 552), 75-79.9 Gy (n = 568), and > or =80 Gy (n = 367). The primary endpoints were freedom from biochemical failure (FFBF), defined by American Society for Therapeutic Radiology and Oncology (ASTRO) and Phoenix (nadir + 2.0 ng/mL) criteria, and freedom from distant metastases (FFDM). Multivariate analyses were performed and adjusted Kaplan-Meier estimates were calculated. Logit regression dose-response functions were determined at 5 and 8 years for FFBF and at 5 and 10 years for FFDM.

Results: Radiotherapy dose was significant in multivariate analyses for FFBF (ASTRO and Phoenix) and FFDM. Adjusted 5-year estimates of ASTRO FFBF for the four dose groups were 60%, 68%, 76%, and 84%. Adjusted 5-year Phoenix FFBFs for the four dose groups were 70%, 81%, 83%, and 89%. Adjusted 5-year and 10-year estimates of FFDM for the four dose groups were 96% and 93%, 97% and 93%, 99% and 95%, and 98% and 96%. Dose-response functions showed an increasing benefit for doses > or =80 Gy.

Conclusions: Doses of > or =80 Gy are recommended for most men with prostate cancer. The ASTRO definition of biochemical failure does not accurately estimate the effects of radiotherapy at 5 years because of backdating, compared to the Phoenix definition, which is less sensitive to follow-up and more reproducible over time.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest: none.

Figures

Fig. 1
Fig. 1
(a) The ASTRO FFBF adjusted Kaplan-Meier estimates for each dose group. (b) The nadir +2 FFBF adjusted Kaplan-Meier estimates for each dose group. ASTRO = American Society for Therapeutic Radiology and Oncology; FFBF = freedom from biochemical failure.
Fig. 1
Fig. 1
(a) The ASTRO FFBF adjusted Kaplan-Meier estimates for each dose group. (b) The nadir +2 FFBF adjusted Kaplan-Meier estimates for each dose group. ASTRO = American Society for Therapeutic Radiology and Oncology; FFBF = freedom from biochemical failure.
Fig. 2
Fig. 2
(a) Adjusted dose–response functions at 5 years for FFBF and FFDM. (b) Adjusted dose–response functions at 8 years for FFBF and 10 years for FFDM. FFBF = freedom from biochemical failure; FFDM = freedom from distant metastases.

Comment in

References

    1. Hanks GE, Hanlon AL, Epstein B, et al. Dose response in prostate cancer with 8–12 years’ follow-up. Int J Radiat Oncol Biol Phys. 2002;54:427–435. - PubMed
    1. Zelefsky MJ, Fuks Z, Hunt M, et al. High-dose intensity modulated radiation therapy for prostate cancer: early toxicity and biochemical outcome in 772 patients. Int J Radiat Oncol Biol Phys. 2002;53:1111–1116. - PubMed
    1. Pollack A, Hanlon AL, Horwitz EM, et al. Prostate cancer radiotherapy dose response: an update of the Fox Chase experience. J Urol. 2004;171:1132–1136. - PubMed
    1. Shipley WU, Verhey LJ, Munzenrider JE, et al. Advanced prostate cancer: the results of a randomized comparative trial of high dose irradiation boosting with conformal protons compared with conventional dose irradiation using photons alone. Int J Radiat Oncol Biol Phys. 1995;32:3–12. - PubMed
    1. Pollack A, Zagars GK, Starkschall G, et al. Prostate cancer radiation dose response: results of the M. D. Anderson phase III randomized trial. Int J Radiat Oncol Biol Phys. 2002;53:1097–1105. - PubMed

Publication types