ACC is likely a rare enough cancer that its treatment is not yet planned for phase I trials, source.
“Adrenocortical carcinoma demonstrates distinct epidemiological patterns with significant geographic and demographic variations. The annual incidence ranges from 0.5 to 2.0 cases per million population worldwide, with approximately 300 to 400 new cases diagnosed annually in the United States. Notable geographic clustering occurs in Southern Brazil, where the incidence ranges from 10 to 15 cases per million children, driven by the prevalent TP53 p.R337H founder mutation.”