It is optional for an American College of Surgeons (ACoS) approved cancer program to:

Including reportable-by-agreement cases in a cancer registry is indeed optional for an American College of Surgeons (ACoS) approved cancer program. The fundamental purpose of cancer registries is to collect data on cancer incidence, treatment, and outcomes. While it is beneficial to acquire comprehensive data, including reportable-by-agreement cases provides flexibility based on the specific goals and requirements of the cancer program.

Reportable-by-agreement cases include those that might not meet certain standard criteria for cancer reporting but are included by mutual agreement between the cooperating organizations. Cancer programs can choose to include or exclude these cases depending on their resources, objectives, and the specific context of their registry initiatives.

On the other hand, maintaining a cancer registry is a fundamental requirement for ACoS approved cancer programs, as it is essential for tracking patient care, contributing to research, and improving outcomes. Therefore, the choice to report specific types of cases, like those reportable-by-agreement, is where the option actually lies, making the assertion regarding it being optional accurate.