。、。
She doesn't care about other people. In other words, she's self-centered.
Literal
She [topic-は] others [genitive-の] thing [object-を] does-not-mind. To-rephrase, self-centered is.
他人のことを気にする is the standard collocation for 'mind / care about others' — ~のことを気にする ('care about X') treats the X as a topic of concern. 自己中心的 ('self-centered, egotistical') is built from 自己 ('self') + 中心 ('center') + suffix 的 ('-istic'). Note 自己中心 is also used as a 四字熟語 (four-character idiom). 言いかえれば ('in other words') is the conditional ~ば of 言いかえる ('to rephrase') — a discourse marker for restatement.