How much does Gleason grade of follow-up biopsy differ from that of initial biopsy in untreated, Gleason score 4-7, clinically localized prostate cancer?
OBJECTIVE
To compare histologic grades between an initial biopsy and a follow-up biopsy in untreated, Gleason score (GS) 4-7, clinically localized prostate cancer.


METHODS
In a prospective single-arm cohort study, clinically localized, GS 4-7, prostate cancer was managed with active surveillance alone, provided that a pre-defined definition of disease progression was not met. One hundred five (63%) of a total of 168 eligible patients underwent a follow-up prostate biopsy during surveillance. Median time to a follow-up biopsy was 22 months (range: 7-81). Histologic grades between these two biopsies were compared to evaluate the extent of histologic grade change.


RESULTS
On the follow-up biopsy, GS was unchanged in 33 patients (31%), upgraded in 37 (35%), and downgraded in 34 (32%). Eleven (10%) had upgrading by 2 Gleason points or more. Eight (8%) had upgrading to GS 8 (none to GS 9 or 10); of these, six were among those with upgrading by 2 Gleason points or more. Twenty-seven (26%) had no malignancy on the follow-up biopsy. Negative follow-up biopsy was more prevalent in patients with a small volume of malignancy in the initial biopsy and a low baseline PSA.


CONCLUSIONS
No consistent change in histologic grade was observed on the follow-up biopsy at a median of 22 months in untreated, GS 4-7, clinically localized prostate cancer. Upgrading to GS > or =8 or by 2 Gleason points or more was relatively uncommon.
Choo
R
R
Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, USA.
Danjoux
C
C
Morton
G
G
Szumacher
E
E
Sugar
L
L
Gardner
S
S
Kim
M
M
Choo
C M
CM
Klotz
L
L
D000230:Adenocarcinoma / Q000097:blood / Q000145:classification / Q000175:diagnosis*; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D011467:Prostate / Q000473:pathology*; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000145:classification / Q000175:diagnosis*