Adverse drug reactions are appreciably harmful or unpleasant reactions resulting from an intervention related to the use of medical products, which predicts hazard from future administration and warrants prevention or specific treatment, or alteration of the dosage regimen, or withdrawal of the product. Given medical case reports extracted from MEDLINE, the task is to classify whether the case report mentions the presence of any adverse drug reaction. Classify your answers into non-adverse drug event and adverse drug event.
--------
Question: The diagnosis of C. difficile was confirmed by a stool-cytotoxin test and endoscopic examination.

Answer: non-adverse drug event


Question: Retrospectively, bucillamine was believed to be the cause of the giant hypertrophy because of its structural similarity to D-penicillamine, which was the subject of an abundance of reports of mammary hyperplasia.

Answer: adverse drug event


Question: Pathology evaluation of a specimen revealed a high-grade osteoblastic osteosarcoma.

Answer:
non-adverse drug event