Expert: John C. M.D. - 1/18/2001

Question
My father-in-law is having surgery for a 6cm mass in the lower bowel at the site of the rectum.  He most definately will have a colostomy. They suspect colorectal cancer.  He had bloody bowel movements for 6 weeks before they found out was was wrong.  My question is: if he has colorectal cancer, what chance is there that he will have metastasis and what the prognosis would be.

Answer
Katie,
A 6cm rectal cancer has a likely chance of having metastases.  I can't give you a number because I don't know of any studies that have looked at the rate of metastases stratified by the size of the primary tumor.  However, I have also seen many patients with this size of tumor that have no metastases at the time of diagnosis.
The prognosis from colorectal cancer depends greatly on the extent of metastases.  Cancers with metastases just to the regional lymph nodes have a much better prognosis than cancers with spread to the liver or distant sites.
Colorectal cancers with spread to the regional lymph nodes only have a long term survival of 40-50% with optimal treatment.  Cancers which spread to the liver or distant sites is much lower, about 5-10%.