Comparison of histologic grade between initial and follow-up biopsy in untreated, low to intermediate grade, localized prostate cancer.
OBJECTIVE
To examine the change of histologic grade of untreated, low to intermediate grade, clinically localized prostate cancer over time on repeat prostate biopsy.


METHODS
In a prospective single-arm cohort study, patients were managed with observation alone unless they met pre-defined criteria of disease progression (PSA, clinical or histologic progression). Sixty-seven (54%) of a total of 123 eligible patients underwent follow-up prostate biopsy. Median time to the follow-up biopsy was 22 months (range: 7-60).


RESULTS
On the follow-up biopsy, Gleason score was unchanged in 20 patients (30%), upgraded in 19 (28%), and downgraded in 27 (40%). Twenty-one (31%) had no malignancy on the follow-up biopsy. Sixteen (37%) of 43 patients with < or = 2 positive cores on the initial biopsy had negative follow-up biopsy, while only 2 (11%) out of 18 with > or = 3 positive cores on the initial biopsy did. Five (7%) patients were upgraded to Gleason score 8. There was no correlation between the extent of grade change and baseline variables (age, clinical stage, and initial PSA) as well as PSA doubling time.


CONCLUSIONS
There was no consistent histologic upgrade on the follow-up biopsy at a median of 22 months in untreated, low to intermediate grade, clinically localized prostate cancer.
Department of Radiation Oncology, Toronto Sunnybrook Regional Cancer Centre, University of Toronto, Toronto, Ontario, Canada.
R
R
Choo
V
V
Do
L
L
Sugar
L
L
Klotz
E
E
Bahk
E
E
Hong
C
C
Danjoux
G
G
Morton
G
G
DeBoer
D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D018450:Disease Progression; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009367:Neoplasm Staging; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000145:classification / Q000473:pathology* / Q000601:surgery
D017430:Prostate-Specific Antigen