Table 3.

Reclassification and the rate of definitive treatment during AS.

Research Group	Inclusion Criteria					Trigger for Definitive Treatment	Rate of Reclassification	Definitive Treatment Rate
	Clinical Stage	Gleason Score	Cancer Volume	PSA (ng/mL)	PSA Density (ng/mL/cm3)
John Hopkins University	T1c	6	≤2 cores positive, ≤50% core involvement per core	-	≤0.15	GS ≥3 + 4, 3 positive cores, >50% cancer per core	26% at 10 years, 31% at 15 years [16]	50% at 10 years, 57% at 15 years [16]
University of Toronto	≤T2a	3 + 3 or 3 + 4 if aged >70 years	-	≤10 or ≤15 if aged >70 years	-	GS upgrading, clinical progression	25.6% (median follow-up: 6.4 years) [14]	27% (median follow-up: 6.4 years) [14]
Memorial Sloan Kettering Cancer Center	≤T2a	6	≤2 cores positive, ≤50% core involvement per core	≤10	-	GS upgrading, clinical progression, upstaging	24% at 5 years, 36% at 10 years, 41% at 15 years [21]	24% at 5 years, 36% at 10 years, 42% at 15 years [21]
University of California, San Francisco	≤T2a	6	<33% positive cores	≤10	-	GS ≥ 3 + 4, PSA velocity >0.75	60% at 7 years [22]	41% at 7 years [22]
Canary Prostate Active Surveillance Study	≤T2c	6 and 3 + 4	-	-	-	GS upgrading, clinical progression, PSA-DT < 3 year	22.4% (median follow-up: 5.6 years) [32,33]	32.5% (median follow-up: 5.6 years) [32,33]
PRIAS	≤T2	≤6	no limitation if MRI available at diagnosis (if not, ≤2 cores positive)	≤20 (if MRI available at diagnosis), ≤10 (if MRI not available)	<0.25 if MRI available at diagnosis (if not, ≤0.2)	progression to ≥T3, GS ≥ 4+3, or GS≤ 3 + 4 with IDC-P/cribriform	34% at 5 years, 41% at 10 years [15]	20.8% (median follow-up: not available) [15]
		3 + 4	≤50% positive cores if MRI available at diagnosis (if not, ≤2 cores positive)	≤20 (if MRI available at diagnosis), ≤10 (if MRI not available)	<0.25 if MRI available at diagnosis (if not, ≤0.2)

PSA, prostate-specific antigen; PRIAS, prostate cancer research international active surveillance; IDC-P, intraductal carcinoma of the prostate; GS, Gleason score.