The definition of biochemical failure in patients treated with definitive radiotherapy

Purpose: The American Society for Therapeutic Radiology and Oncology (ASTRO ) published a definition for biochemical failure following treatment of pro state cancer. Others have noted difficulties with interpreting this definit ion and recommended modifications to accommodate special recurrence pattern s. We have compared various modifications to the original ASTRO definition on our series of 1213 patients treated with transperineal permanent prostat e brachytherapy. Methods and Materials: The ASTRO modifications we considered adjusted for ( I) early censoring of nonrecurrent patients with rising prostate-specific a ntigen levels (PSA), (2) cumulative rather than consecutive rises (without a decrease) as evidence of recurrence, (3) both of the above, and (4) waiti ng 2 years before data analysis, The Kaplan-Meier method was used to comput e the effects on recurrence rate for patients treated with and without neoa djuvant hormones. Results: With the original ASTRO definition, freedom from recurrence in our series of men who did not receive neoadjuvant hormones was 83% at 4 years. All of the modifications considered had statistically insignificant effect s on freedom from recurrence rates, varying from 80% to 83% at 4 years. Pat ients treated with neoadjuvant hormones also showed very little sensitivity to the recurrence definition employed. Conclusion: Early censoring of equivocal patients and counting cumulative r ather than consecutive rises in PSA (without a decrease) had little empiric effect on the ASTRO recurrence rates. However, we favor the addition of bo th these modifications to the ASTRO definition on conceptual grounds for ev aluating patients following any modality (radiation or surgery), whereby a trend over multiple PSA values is used to judge failure, (C) 2000 Elsevier Science Inc.