Monarch Disease Ontology term MONDO_0021509 (benign neoplasm of myocardium) is a benign neoplasm that involves the myocardium. Also known as: benign myocardial neoplasm, benign myocardial tumor, benign myocardial tumour, benign neoplasm of the myocardium, benign tumor of myocardium, benign tumor of the myocardium, benign tumour of myocardium, benign tumour of the myocardium.