Prognosis for patients under 30 years is difficult or worse. A worse prognosis can be identified by a high CEA level. Moreover, prognosis of a cancer, here bowel cancer is usually determined by the morphology, stage of tumor and its histology. Cancer at its stage 1 has a 90% survival rate at 5 years while a cancer at stage 4 will have just under 5% survival rate at 5 years. Good luck and stay healthy.