For unguided, general-purpose annotation, the number of relations that could be annotated grows quadratically with the number of events and times, and the task quickly becomes unmanageable.
based on the known progression-of-care for colon cancer, we can infer that the colonoscopy occurs first, biopsies occur during the colonoscopy, pathology happens afterwards, a diagnosis (here, adenocarcinoma) is returned after pathology, and resection of the tumor occurs after diagnosis.