Table 1. Concordances and discordances among breast cancer surveillance recommendations.

	North American Children's Oncology Group	Dutch Childhood Oncology Group	UK Children's Cancer and Leukaemia Group	Concordant/ discordant
Who needs breast cancer surveillance?
At risk
Chest radiation	Yes	Yes	Yes	Concordant
± Alkylating agents	Not specified	Not specified	Yes	Discordant
High risk	Not specified	≥7-20 Gy chest radiation (excl. TBI) ≥14-40 Gy abdominal radiation	Not specified	Discordant
Highest risk	≥20 Gy chest radiation	≥20 Gy chest radiation ≥40 Gy abdominal radiation TBI	Not specified	Discordant
At what age should breast cancer surveillance be initiated?
	25 yr	25 yr	25 yr	Concordant
At what frequency should breast cancer surveillance be performed?
	Every 1 yr	Every 1 yr	Every 1 yr	Concordant
At what age should breast cancer surveillance be stopped?
	No age limit	75 yr	No age limit	Discordant
What surveillance modality should be used?
Screening test
Clinical breast exam	Yes	Yes	Yes	Concordant
Mammography	Yes	Yes	Yes	Concordant
Breast MRI	Yes	Yes	Yes	Concordant
Age at initiation
Clinical breast exam	Puberty	25 yr (highest risk) 35 yr (high risk)	25 yr and >10 yr after chest radiation	Discordant
Mammography	25 yr or 8 yr after chest radiation	30 yr (highest risk) 35 yr (high risk)	30 yr	Discordant
Breast MRI	25 yr or 8 yr after chest radiation	25 yr (highest risk)	25 yr	Concordant
Surveillance frequency
Clinical breast exam	Every 0.5 yr (age >25 yr) Every 1 yr (puberty to age 25 yr)	Every 1 yr	Regularly	Discordant
Mammography	Every 1 yr	Every 1 yr (age 30-60 yr) Every 2 yr (age 60-75 yr) (highest risk) Every 1 yr (age 35-60 yr)Every 2 yr (age 60-75 yr)(high risk)	Every 1 yr (age 30-50 yr) Every 3 yr (age >50 yr)	Discordant
Breast MRI	Every 1 yr	Every 1 yr (age 25-60 yr)	Every 1 yr (age 25-29 yr and 30-50 yr if dense breast tissue)	Partly concordant

TBI = total body irradiation.