Page 77 - An Evidence Review of Active Surveillance in Men With Localized Prostate Cancer

Followup Protocols of AS Cohorts (Tables 4 and 5)
All 16 cohorts included regular PSA testing in the followup protocol (Tables 4 and 5). DRE
was included in the followup protocols of 12 of the cohorts. Fourteen cohorts included routine
rebiopsy (Figure 5). The testing frequency of PSA, DRE, and rebiopsy varied across the cohorts.
One cohort also incorporated a regular bone scan schedule. Criteria for recommending curative
treatments varied across the cohorts. The recommended treatments were not standardized and
were left at the discretion of treating physicians and patients in many of the cohorts.

Gleason score. Twelve cohorts (21 publications) used the Gleason score as part of monitoring
criteria for disease progression. 106-108,110-115,117,119-121,124,125,127-132 Generally, disease progression
was defined as a Gleason score or pattern greater than those used in the eligibility criteria for AS
(Table 2). One cohort did not use the Gleason score as part of eligibility criteria for AS, but
reported the use of any increase in the Gleason grade as part of monitoring criteria for disease
progression. 121

Number of cores positive for cancer. Eight cohorts (9 publications) used the minimal number
of biopsy cores positive for cancer as part of monitoring criteria for disease progression. 106-
108,110,113,115,117,118,120 Two criteria were used: 3 or more (6 cohorts) and greater than 4 (3 cohorts)
positive biopsy cores. One cohort reported that “an increased number of cores positive for
cancer” was used as one of the parameters for defining disease progression but the specific
number of cores was not reported. 108 The rebiopsy frequencies varied across the cohorts (Figure
5).

Percentage cancer involvement in each core. Six cohorts (8 publications) used more than 50
percent cancer involvement in each biopsy core as part of monitoring criteria for disease
progression. 107,112,113,115,117,124,128,132 Two other cohorts considered an increase in tumor volume as
part of monitoring criteria for disease progression, but specific percentage cancer involvement
was not reported. 108,119

PSA. All 16 cohorts included regular PSA testing in the followup protocol. The testing
frequency varied across the cohorts (Figure 5). Six cohorts considered rising PSA and/or PSA
kinetics as part of triggers for treatment but did not specify the detailed criteria. One cohort
explicitly reported that PSA kinetics was not used as part of triggers for intervention. Nine
cohorts used a variety of PSA triggers for treatment (Figure 5): PSA doubling time ranging from
<1 to <4 years (6 cohorts), various PSA velocity criteria (4 cohorts), and PSA greater than 10
ng/mL (1 cohort). The number of cohorts do not sum to the total number of cohorts because
some cohorts used multiple criteria. Of these, Toronto-Sunnybrook Regional Cancer Center
cohort changed the original PSA doubling time trigger (PSA doubling time < 2 years in the first
4 years of the study) to PSA doubling time < 3 years in 1999. 130 In 2005, the same group also
added risk zone to the protocol (the group developed a clinical decision making aid that can
define 3 risk zones of high, intermediate and low risk of reclassification when overlaid with PSA
130
data from each patient). A patient with a PSA consistently in the high risk zone is
recommended to undergo treatment. Two cohorts did not use PSA kinetics as a trigger for
treatment. 113,117

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