mamalouise

I have a 4 year old daughter who has had chronic constipation for just about as long as I can remember,therefor she sees a GI doctor for.She takes miralax daily for the constipation and also has GERD and she takes famotidine for it.She has had 2 episodes that I know of where she has vomitted large amounts of blood the color of coffee grounds,and it was enough to lower her hemoglobin levels,but not to a dangerous level.Her GI doctor performed and endoscopy with biopsies and found nothing.She has had 3 hemoccult tests done to check for blood in her stools and they were all negative.She complains all the time that her belly hurts and she has recently started having urinary incontinence.When her endoscopy was performed,the doctor did a rectal exam and said she felt a "growth".3 months after the growth was initially felt,she went back for her follow up and the doc performed another digital rectal exam and said that the growth had gotten quite a bit bigger in just the 3 months and it is necessary to do a colonoscopy.I am very concerned because on her dads side of the family cancer runs very heavily.3 of her 4 great grandparents died from cancer (one colon cancer,one lung cancer,and the other prostate cancer),and her grandmother has nonhodgkins lymphoma.My mother (my daughters grandmother) is only 42 and has had 10 polyps removed that were cancer causing type. I have been reading up on "growths that can be felt during a digital rectal exam", but it is very vague. Everything I read about colon polyps says it usually takes 2-3 years for them to grow the size of a pencil eraser,so I am wondering how whatever "growth" she has could have grown so quickly in 3 months? I am very concerned and am hoping somebody can give their input what types of things this could be? Please and Thanks for all of your help!