Table 1. Summary of monitoring tools, timing of monitoring tools and criteria for switching to definitive therapy.

Category	Monitoring tools	Triggers for definitive therapy
Follow-up monitoring and triggers for definitive therapy recommendations in guidelines
Guideline
EAU (10)	Serum PSA, DRE and rebiopsy mentioned	NR***
NCCN (11)	Serum PSA ≤6 months, unless clinically indicated, DRE ≤12 months unless clinically indicated, rebiopsy ≤12 months unless clinically indicated or at 6 months if the initial biopsy sample had <10 cores, MRI mentioned	Rebiopsy sample GS contains grade 4 or 5 disease, increased number of tumor-positive cores or increased extent of cancer per core
NICE (12)	Serum PSA, 3–4 months year 1 post-diagnosis, every 3–6 months year 2–4 and then every 6 months, PSA kinetics measured throughout AS, DRE every 6–12 months year 1–4 and then annually, rebiopsy 12 months after diagnosis or if concern exists about clinical or PSA changes, MRI at enrollment f not done, before or in the presence of concern about clinical or PSA changes.	Switching recommended if disease progression observed, also taking into account patient’s life expectancy, preferences and comorbidities
GSU (13)	Serum PSA every 3 months year 0–3 post-diagnosis, every 6 months thereafter, PSA kinetics mentioned, DRE every 3 months year 0–3 post-diagnosis then every 6 months, if PSA stable rebiopsy every 12–18 months within 3 years post-diagnosis, then every 3 years	PSA >10 ng/mL, PSA-DT <3 years, tumor stage > cT2a, repeat biopsy GS >6, >2 tumor-positive cores, >50% cancer per biopsy core
KCE (14)	Serum PSA every 6 months, DRE every 6 months, rebiopsy within 1-year and repeated thereafter, annual MRI	PSA>10 ng/mL, PSA-DT <3 years, clinical change detected during DRE, or suspicious lesions on MRI
FCCG (15)	Serum PSA, DRE and rebiopsy mentioned	PSA-DT <3 years, repeat biopsy GS >6, >2 tumor-positive cores, or disease is reclassified as clinically relevant
SCAN (16)	Serum PSA every 3 months year 1 post-diagnosis, every 6 months thereafter, PSA-DT after 5 PSA measurements, DRE ≤6 months, repeat biopsy within 6 months post diagnosis then years 1, 4, 7, and 10	PSA-DT <3, progression of palpable T2-stage disease on DRE or palpable lesions appearing. GS 4 or 5 at rebiopsy >50% spread of cancer in any one core, >50% of core samples, or bilateral disease
CCNS (17)	Serum PSA every 6 months, DRE every 6 months, rebiopsy at 6 months if initial biopsy <10 cores or findings discordant with clinical findings, within 18 months otherwise, periodically thereafter	Switch recommended at disease progression
I+CS (18)	Serum PSA every 3 months 0–3 years post-diagnosis, every 6 months thereafter, PSAV with at least 5 PSA measurements, DRE every 3 months within year 0–2 post-diagnosis, every 6 months thereafter, rebiopsy year 1, 4, and 7 post-diagnosis	PSAV >1 ng/mL, DRE, rebiopsy GS, number of tumor-positive cores, maximum extent of cancer per core all mentioned
AHS (19)	Serum PSA every 3–6 months, PSA kinetics mentioned, DRE annually, rebiopsy year 1–2 post-diagnosis, every 2–3 years thereafter or as clinically indicated	PSA-DT <3 years, increase clinical stage from baseline at DRE, Gleason pattern 4 or higher, >50% of cancer in any one core, patient preferences
CCO (20)	Serum PSA every 3–6 months, DRE annually, rebiopsy 6–12 months post-diagnosis, every 3–5 years thereafter, MRI mentioned	Repeat biopsy GS ≥7 with pattern 4 accounting for >10% of the total tumor and/or significant increase in tumor volume
PCT (21)	Serum-PSA every 6 months, or every 3 months when concern of progression, DRE mentioned, PSA kinetics mentioned, repeat biopsy within 12 months of initial biopsy or when clinically indicated	NR
Follow-up monitoring recommendations of cohorts in the GAP3 database
Center*
USA
JHU	Serum PSA every 6 months, DRE every 6 months, rebiopsy every 12 months
UCSF	Serum PSA every 3 months, DRE every 6 months, rebiopsy every 12–24 months
MSKCC	Serum PSA every 6 months, DRE every 6 months, rebiopsy every 3 years, mpMRI every 18 months
MDACC	Serum PSA every 6 months, DRE every 12 months, rebiopsy every 12–24 months
EU	Serum PSA every 6 months, DRE every 12 months, rebiopsy every 12 months, mpMRI annually for the first 3 years then final after 5 years
MUSIC	Serum PSA every 3–6 months, DRE every 12 months, rebiopsy every other year, mpMRI every other year and confirmatory test in first 3–4 months
Canada
UOFC	Serum PSA every 6 months, DRE every 6 months, rebiopsy at year 1 then every 2 years, mpMRI when PSA >10 ng/mL
UOFT	Serum PSA every 3 months until 2 years, then every 6 months, PSA kinetics every 12 months, DRE every 6 months, rebiopsy at year 1, 4, 7, 10, and 15, mpMRI every 12 months
United Kingdom
GSTT	Serum PSA every 6 months, PSA kinetics every 12 months, DRE every 12 months, mpMRI every 12 months
UCL	Serum PSA 3–4 monthly in year 1 then every 6 months, rebiopsy for men with change in MRI and uncertainty about switch to definitive therapy, mpMRI at baseline and 12 months the dependent on risk factors including MRI, PSA density and GS
Camb	Serum PSA every 3 months, rebiopsy within 1 year post-diagnosis, then at 36 and 60 months and if mpMRI shows a change, mpMRI every 12 months
Europe
KSB	Serum PSA every 6 months, DRE every 6 months, rebiopsy every 24 months
UCD	NR
SU	Serum PSA every 3–6 months, DRE every 6–12 months, rebiopsy every 2–3 years
Lille-U	Serum PSA every 6 months, DRE every 12 months, rebiopsy at month 12, mpMRI at month 12
SUS	Serum PSA every 3 months, DRE every 6 months, rebiopsy after month 12, 48, and 84
INT-MILAN (SAINT)	Serum PSA every 3 months, PSA kinetics after first year every 3 months, DRE every 6 months, rebiopsy every 12 months first 2 years, then every 24 months
INT-MILAN (PRIAS)	Serum PSA every 3 months, PSA kinetics after first year every 3 months, DRE every 6 months, rebiopsy after 12, 48, and 84 months
IVO	Serum PSA every 6 months, DRE every 6 months, rebiopsy at month 6 and 24 then every 3 years, mpMRI before every biopsy
Australasia
MEASCAP	Serum PSA every 3 months, DRE every 6 months, rebiopsy month 12, 48 and 84
SGH	Serum PSA every 3–6 months first 2 years then every 6–12 months, PSA kinetics every 12 months, DRE every 12 months, rebiopsy every 12 months, mpMRI every 12 months
YUHS	Serum PSA every 3 months, rebiopsy considered when change on mpMRI is detected, mpMRI every 12 months
KU	Serum PSA every 2 months for 6 months then every 3 months, DRE every 12 months, rebiopsy every 12 months
Other
PRIAS**	Serum PSA every 3 months, PSA kinetics every 6 months, DRE every 6 months, rebiopsy after 12, 48, and 84 months

*, Institute abbreviations: JHU, Johns Hopkins University, Baltimore, USA; UCSF, University of California, San Francisco, San Francisco, USA; MSKCC, Memorial Sloan Kettering Cancer Center, New York, USA; MDACC, MD Anderson Cancer Centre, Houston, USA; EU, Emory University School of Medicine, Winship Cancer Institute, Atlanta, USA; MUSIC, University of Michigan and Michigan Urological Surgery Improvement Collaborative, Michigan, USA; UOFC, University of Calgary, Southern Alberta Institute of Urology, Calgary, Canada; UOFT, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Canada; GSTT, Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom; UCL, University College London & University College London Hospitals Trust, London, United Kingdom; Camb, Cambridge University Hospitals NHS Trust, Cambridge, United Kingdom; KBS, Kantonsspital Baden, Baden, Switzerland; UCD, University College Dublin, Dublin, Ireland; SU, Sahlgrenska University Hospital, Göteborg, Sweden; Lille-U, Lille University Hospital Center, Lille, France; SUS, Skåne University Hospital, Malmö, Sweden; INT-MILAN, Fondazione IRCCS Istituto Nazionale dei Tumori di Milano, Milan, Italy; IVO, Instituto Valenciano de Oncología, Valencia, Spain; MEASCAP, Monash University and Epworth HealthCare, Melbourne, Australia; YUHS, Gangnam Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea; KU, Kagawa University Faculty of Medicine, Kagawa, Japan. **, PRIAS (Prostate Cancer Research International Active Surveillance): includes Erasmus Medical Center, Rotterdam, the Netherlands; Helsinki University Central Hospital, Helsinki, Finland; University of British Columbia, BC Cancer Agency, Vancouver, Canada). ***, NR, not reported.