The best example I have found so far

It was a gift to satirists to learn that Peter Mandelson had a problem with a benign prostate. The general theme has been around the idea of something malignant getting rid of the only benign part. Resistance is Useless has the best one that I have seen so far with a piece entitled "Well Loved Growth in Emergency Op Shock ", here are the best bits:

"One of the UK's best loved tumours has been admitted to St. Mary's Hospital, Paddington for urgent surgery to remove a malignant First Secretary of State. The tumour, known locally as Colin, was described by neighbouring cells as 'A lovely growth' and 'benign as you could wish for, not like that malevolent arsehole that surrounded him'.

Interviewed earlier, Colin had this to say. "Well, one day you're just dividing normally, dreaming of the day you can get on and metastasise and then wallop! You find you've developed an unelected fraudulent two-time loser""