Conditional probability of reclassification in an active surveillance program for prostate cancer

Ridwan Alam, H. Ballentine Carter, Patricia Landis, Jonathan I. Epstein, Mufaddal Mamawala

Research output: Contribution to journalArticlepeer-review

Abstract

Purpose We evaluated the risk of prostate cancer reclassification by time on active surveillance. Materials and Methods From 1995 to 2014 we evaluated 557 and 251 men at very low and at low risk, respectively, who were on active surveillance and compliant with prostate biopsies. Our primary study outcome was reclassification to higher risk disease by grade or extent. Freedom from reclassification was estimated using the Kaplan-Meier approach with adjustment for covariates using the Cox proportional hazards model. Results Within the first 2 years of surveillance patient survival free of reclassification by grade (p = 0.20) and by any biopsy criteria (p = 0.25) was similar in men with very low and low risk disease. After 2 years men with low risk disease were 2.4 times more likely to be diagnosed with a Gleason score of greater than 6 than men with very low risk disease (p = 0.002, HR 2.4, 95% CI 1.9-3.5). Additionally, beyond 2 years on surveillance the risk of lifetime reclassification by grade and by any criteria decreased by 30% and 35% (each p <0.0001, HR 0.70, 95% CI 0.60-0.76 and HR 0.65, 95% CI 0.57-0.72, respectively) with each biopsy that showed no reclassification. Conclusions The reclassification rate during surveillance is not equally distributed across time or risk groups. Due to misclassification at diagnosis the reclassification rate in very low and low risk groups is similar in the first 2 years but differs significantly beyond 2 years. The risk of reclassification decreases with time for each nonreclassifying biopsy beyond 2 years.

Original languageEnglish (US)
Pages (from-to)1950-1955
Number of pages6
JournalJournal of Urology
Volume193
Issue number6
DOIs
StatePublished - Jun 1 2015

Keywords

  • classification
  • diagnosis
  • prostate-specific antigen
  • prostatic neoplasms
  • risk

ASJC Scopus subject areas

  • Urology

Fingerprint Dive into the research topics of 'Conditional probability of reclassification in an active surveillance program for prostate cancer'. Together they form a unique fingerprint.

Cite this