three weeks ago I saw the local doctor lady.. she listened to my description of abdominal pain down the left groin area. now the pain is occasionally not nice and there is a swelling which is uncomfortable to touch when I have the pain . The swelling is soft like a liquid pouch. I have undergon Prostrate cancer Radiotherapy which resulted in occasional mucus and blood discharge when passing stool and wind. This mucky bum has settled down and for some months I have not had any accidents (soiled pants). The doctors letter said iI had a friable back passage which bled on contact. I am due for Colonoscopy. What should I do? is it dangerous to undergo the colonoscopy with a friable weakened colon . I  am 68 year old white male. 6ft 4  tall 84 kg. reasonably fit and active.

Summarized question: is it dangerous to undergo colonoscopy with a friable weakened colon?