noun
nonexpansion; localization; nonaggravation
Technical term used in medical or scientific contexts to indicate that a condition, lesion, or process is not spreading or worsening. The glosses 'localization' and 'nonaggravation' reflect specific clinical uses.
CT検査で腫瘍の不拡大が確認された。
CT examination confirmed nonexpansion of the tumor.
この治療法は病変の不拡大を目的
This treatment aims at localization of the lesion.
非拡大 is a similar term meaning 'non-expansion', but 不拡大 is more common in medical usage.
Compound of 不 (negative prefix) and 拡大 (expansion). The exact historical derivation is uncertain, but the term is used in modern technical Japanese.