Wide variation of prostate-specific antigen doubling time of untreated, clinically localized, low-to-intermediate grade, prostate carcinoma.
OBJECTIVE
To assess the prostate specific antigen (PSA) doubling time of untreated, clinically localized, low-to-intermediate grade prostate carcinoma.


METHODS
A prospective single-arm cohort study has been in progress since November 1995 to assess the feasibility of a watchful-observation protocol with selective delayed intervention for clinically localized, low-to-intermediate grade prostate adenocarcinoma. The PSA doubling time was estimated from a linear regression of ln(PSA) against time, assuming a simple exponential growth model.


RESULTS
As of March 2003, 231 patients had at least 6 months of follow-up (median 45) and at least three PSA measurements (median 8, range 3-21). The distribution of the doubling time was: < 2 years, 26 patients; 2-5 years, 65; 5-10 years, 42; 10-20 years, 26; 20-50 years, 16; >50 years, 56. The median doubling time was 7.0 years; 42% of men had a doubling time of >10 years.


CONCLUSIONS
The doubling time of untreated clinically localized, low-to-intermediate grade prostate cancer varies widely.
Toronto-Sunnybrook Regional Cancer Center, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada. richard.choo@tsrcc.on.ca
Richard
R
Choo
Laurence
L
Klotz
Gerrit
G
Deboer
Cyril
C
Danjoux
Gerard C
GC
Morton
D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D018450:Disease Progression; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology / Q000628:therapy
D017430:Prostate-Specific Antigen