It appears that the name kankerlijer is an insult meaning "cancer patient", sort of like how in the US the phrase "fucking cunt" might be used (except without the gendered notion - just in severity).

Didn't know so caching this here for others.

a lot of dutch curses and insults come from diseases (kanker/cancer and typhus are common). one of a few things i really appreciate about the Dutch language is they really make the most of a relatively small common vocabulary (compared to english).

See also: https://en.wikipedia.org/wiki/Dutch_profanity