A benign mesenchymal neoplasm arising from smooth, skeletal, or cardiac muscle tissue. The disease is MONDO_0003061 (benign muscle neoplasm). Also known as: benign muscle tumor, benign muscle tumour, benign neoplasm of muscle, benign neoplasm of the muscle, benign tumor of muscle, benign tumor of the muscle, benign tumour of muscle, benign tumour of the muscle.