New endpoints in adrenocortical carcinoma studies: a mini review

Adrenocortical carcinoma (ACC) is a very rare and aggressive malignant disease. Therefore, overall survival (OS) has long been considered as the best endpoint. Yet, a unique endpoint is not optimal to take into account the heterogeneity in tumor profile and the diversification of therapeutic option. The purpose of this mini review was to describe endpoints used in the past, present and future in the field of ACC.

Pubmed and Clinicaltrial.gov were used to identify relevant studies.

Before year 2000 only three endpoints were regularly used: OS, recurrence-free survival (RFS) and response rate. These endpoints were used because ACC was seen as a homogeneous diseases with a high recurrence rate and low rate of long-term survival. Since 2000; along with the apparition of new class of drug, progression-free survival (PFS) has been more and more used. Other endpoints as "time to chemotherapy" or "Progression-free survival 2" were used to evaluate multimodal therapies or treatment with a delayed action. Finally, there is a hope that in the near future, quality of life along with other patient-reported outcomes may be used more frequently.

While OS and PFS are currently the most used endpoints in ACC, new endpoints are needed to better take into account the challenges offered by different situations and treatment strategies.