The word cancer has been adopted into the English language to mean an evil condition or thing that spreads destructively.
The article makes no reference to the medical condition, nor the star sign, nor the tropics of.
I don't care much for this article, but the author has used the word cancer in context without belittling the medical condition and it is unfair of you to imply that he has.
Especially since you compare his writing style to one of the most despot genocidal maniacs of our time.