LAUSR

Many children with cancer are diagnosed during infancy and toddlerhood (< 3 years of age), potentially resulting in disrupted and/or missed developmental opportunities. Our objective was to describe the functioning of infants and toddlers with cancer who were clinically referred for evaluation at a hospital-based psychology clinic. Data from 29 very young children with cancer ( M age  = 23.62 ± 6.6 months; 55.2% male) who completed clinically referred assessments from 2010 to 2015 were abstracted. Children were 11.3 months post-diagnosis ( SD  = 7.77, range 1–29 months) with just over half off-therapy at the time of assessment (55.2%). Overall, developmental functioning was significantly below expectations [ t (22) = − 8.99, p  < .001]. Adaptive functioning [ t (25) = − 6.41, p  < .001] was also significantly below expectations. Infants and toddlers with cancer appear to be at significant risk for weaknesses in early cognitive and adaptive functioning. The margin of deficits found in this study warrant the need for further investigation and consideration of this young population to ensure optimal functional development.