And it's true that Khoury, who writes largely in a colloquial Arabic, has been a major innovator both stylistically and topically.
1580s, from topic + -al (1). Medical sense is from c.1600. Meaning "of or pertaining to topics of the day" is from 1873.
topical top·i·cal (tŏp'ĭ-kəl)adj. Of or applied to a definite or localized area of the body.