Men on AS typically have a confirmatory prostate biopsy within a year of the initial diagnostic biopsy followed by serial PSA testing and biopsies. Previous reports of Gleason score upgrading suggest that this occurs in the first two years and reflects sampling error. This study evaluated Gleason grade changes over a longer time period.
A total of 377 men from their database met inclusion criteria for study. The PSA followup was every 3 months and serial biopsies performed at 12-24 month intervals. At diagnosis, mean age was 61.9 years and 53% had a PSA of ≤6ng/ml. Mean number of cores taken at diagnostic biopsy was 13 and only 7% had fewer than 10 cores. The mean followup time from diagnostic biopsy was 54 months and 205 men (54%) had two or more repeat biopsies, 109 (29%) had 3 or more, 48 (13%) had 4 or more, 23 (6%) had 5 or more, 11 (2%) had 6 or more, 4 (1%) had 7, and one had eight biopsies. Pathologic upgrading at first repeat biopsy occurred in 81 min (21%). There were 198 men without change in their Gleason score between the first and second biopsy and of these only 24 (12%) had upgrading after second repeat biopsy. Sixty-nine men had upgrading at the third prostate biopsy. The finding of no cancer at the first confirmatory biopsy occurred in 91 men (24%) of those with Gleason score 6. They found 129 had grade progression, 98% of whom were upgraded to Gleason 7 (3+4); the median number of cores involved in the upgrade was one and median percentage of Gleason grade 4 involved was 15%. Interestingly, 37% of the men with upgrade did so at a biopsy site not containing CaP on the initial biopsy and 33% had upgrading at a site containing CaP on a previous biopsy. The 5-year treatment-free rate for those with upgraded Gleason grade was 40%, compared to 80% for those without upgrading. Interestingly, among 62 men who underwent radical prostatectomy for either upgrading or by choice, 20% were downgraded on final pathology, 59% remain unchanged and 21% had further upgrade in Gleason score. Thirty-six percent of men with upgrading on biopsy (46 men) declined intervention and remain on AS.
Porten SP, Whitson JM, Cowan JE, Cooperberg MR, Shinohara K, Perez N, Greene KL, Meng MV, Carroll PR
J Clin Oncol. 2011 Jul 10;29(20):2795-800