I chose that word on purpose because of both its semantic and emotional power. Besides, I'm pretty happy that all the critics have been focused on either using the term "cancer" or the swearing at the end, so I guess my points are valid to almost everyone, and you just didn't like the way I expressed them. That sound ok.
First off, the comparison to Hitler is not hyperbole or misapplied metaphor. Hitler literally compared the Jews to cancer, please see: http://www.dailymail.co.uk/news/article-1233707/Hitlers-hatr...
Second, it's not clear to me that you do appreciate mechanical_fish's feelings. His point is that cancer is an outsized, heavy word, and regardless of the author's intent, the word has connotations that neither you nor the author can shake loose from the word.