Negative Bx during AS linked with lower risk of reclassification

Monday, June 25 2018

Prostate Cancer , Genitourinary Cancers
“Journal Article of the Month” is a new Urology Times section in which Badar M. Mian, MD (left), offers perspective on noteworthy research in the peer-reviewed literature. Dr. Mian is associate professor of surgery in the division of urology at Albany Medical College, Albany, NY.
Repeat prostate biopsy is an essential component of active surveillance protocols for low-risk prostate cancer. Often, multiple repeat biopsies are performed at variable intervals to capture any cancers that may have worsened to higher risk classification while still at a curable stage. However, a recent study by Kearns et al concluded that those men whose surveillance biopsies are free of cancer are at fairly low risk of being reclassified to a worse category (Eur Urol 2018; 73:706-12).
The optimal number, frequency, and candidate for surveillance biopsies have not been well defined. The authors sought to determine the pathologic outcome and the risk of upgrading or reclassification in subsequent repeat biopsies. This report is from a multicenter cohort study (Canary Prostate Active Surveillance Study) that enrolled patients with low-risk prostate cancer who were monitored with PSA test, clinic visits, and surveillance prostate biopsy at 1 year, 2 years, and then every 2 years. The average age of this cohort was 63 years, median PSA was 4.9 ng/mL, and the median prostate volume was 42 cc. The majority (94%) of patients had Gleason 3+3 cancer involving one or two biopsy cores.
Also by Dr. Mian: PRECISION data lend validation to utility of multiparametric MRI
The authors identified 657 men who have undergone at least one surveillance biopsy and 313 men who had undergone a second surveillance biopsy. Reclassification to a higher category was defined as an increase in Gleason score or in the number of cores with cancer.
Of the 657 men undergoing first surveillance repeat prostate biopsy, 214 biopsies (32%) were cancer free, 282 (43%) had cancer but no reclassification, and 161 (25%) were reclassified to worse disease. At the second surveillance biopsy performed in 313 men, 120 (38%) showed no cancer, 139 (44%) had cancer without reclassification, and 54 (17%) were reclassified due to increased volume or grade.
On multivariable analysis, having no cancer in the first surveillance biopsy was protective against higher classification on the second surveillance biopsy. Similarly, if the second surveillance biopsy was free of cancer, it was a strongly predictive of lack of reclassification on subsequent biopsies.