I-Carcinomaofrectum ibizwa ngokuba ngumhlaza we-colorectal, lithumba eliqhelekileyo elibi kwi-gastrointestinal tract, isehlo sesibini kuphela kumhlaza wesisu kunye nommizo, yeyona ndawo ixhaphakileyo yomhlaza wesisu (malunga ne-60%).Uninzi lwezigulane zineminyaka engama-40 ubudala, kwaye malunga ne-15% ingaphantsi kweminyaka engama-30 ubudala.Indoda ixhaphake kakhulu, umlinganiselo wendoda ukuya kwesetyhini ngu-2-3: 1 ngokujongwa kweklinikhi, kufunyenwe ukuba inxalenye yomhlaza we-colorectal ivela kwi-polyps okanye i-schistosomiasis;ukuvuvukala okungapheliyo kwamathumbu, ezinye zinokubangela umhlaza;ukutya okunamafutha aphezulu kunye neprotheyini ephezulu kubangela ukwanda kwe-cholic acid secretion, le yokugqibela ichithwa kwi-polycyclic hydrocarbons engaxutywanga yi-intestinal anaerobes, enokubangela nomhlaza.