A neoplasm (disease) that involves the myocardium. The disease is neoplasm of myocardium (Monarch Disease Ontology id MONDO_0021380). Also known as: myocardial neoplasm, myocardial tumor, myocardial tumour, myocardium neoplasm, myocardium neoplasm (disease), myocardium tumor, myocardium tumour, neoplasm of the myocardium.