Oncology products developed for adult cancers often receive full waivers of pediatric studies. This analysis retrospectively identified products with potential pediatric development opportunities despite a full waiver. Initial pediatric study plans submitted to the US Food and Drug Administration from 2012 to 2016 for oncology products with plans to request full waivers of pediatric studies were reviewed to determine if a scientific rationale existed for pediatric evaluation based on the molecular mechanism of action (MOA), clinical experience, nonclinical evidence, or published genome sequencing data. Of the 98 oncology products reviewed, pediatric studies were eventually conducted in 55 (56%) despite having a waiver, 33 additional (34%) products were considered to have a rationale for pediatric evaluation but were not studied, and 10 (10%) products had no current evidence to support pediatric development. Conducting pediatric studies based on molecular MOA, rather than indication, provides opportunities to evaluate products earlier and accelerate pediatric oncology drug development.