The Impact of Tumor Volume on Outcomes after Radical Prostatectomy: Implications for Prostate Cancer Screening

Abstract

Purpose: For screening to make an impact on prostate cancer mortality, detection of potentially lethal cancers at an early stage when they are low volume should result in improved recurrence and death rates after treatment. Patients and Methods: The effect of tumor volume on prostate cancer recurrence and death was evaluated in 764 men who underwent radical prostatectomy between 1984 and 2004, with particular attention focused on patients with moderate and high risk features. Results: Tumor volume was a powerful predictor of recurrence in men after radical prostatectomy with moderate and high risk features, even after accounting for the effects of percentage Gleason pattern 4/5 cancer, extracapsular extension, seminal vesicle invasion, lymph node metastasis, pre-operative PSA, and surgical margin involvement. In a subset of 159 patients for whom pre-operative PSA velocity was available, tumor volume predicted recurrence in those in the highest risk category (PSAV > 2 ng/ml/yr). Tumor volume, along with percent grade 4/5 and positive surgical margins, was sig- nificantly associated with prostate cancer specific death. Conclusions: The association of volume with outcome after radical prostatectomy, particularly in high risk patients, sug- gests that screening has made a positive impact on prostate cancer mortality. Future screening efforts should be directed at finding cancers with moderate and high risk features at low volume.