noun
malignancy; grade of malignancy
Medical term referring to the degree of malignancy of a tumor or cancer. Used in pathology and oncology.
この腫瘍は悪性度が高い。
This tumor has a high grade of malignancy.
病理医が悪性度を評価した。
The pathologist assessed the malignancy grade.
良性 means 'benign', the opposite of malignant. 悪性度 is not directly contrasted with a single term for 'benignity grade'.
Compound of 悪性 (akusei, 'malignant') and 度 (do, 'degree'). The term is a direct translation of the medical concept 'malignancy grade'.