Rainbow:
The first move is to biopsy the tumor and/or resect the colon at the same time. The GI who did the colonoscopy should be able to tell you whether he/she believes the tumor is cancerous, however. Final staging, however, generally is done when the pathology report comes back about a week or so after removal of the tumor. What do they tell you they are waiting for? Ask the GI or surgeon his or her impressions as to whether this is cancerous, size, location, etc.
Good Luck,
CancerDad