ADENOCARCINOMA OF THE ILEOCECAL VALVE
DISTINCTIVE FEATURES OF COLONIC CARCINOMAS
Is the second most common tumor in the US.
Accounts for 58,000 deaths in the US.
Is most commonly found in the 6th to 7th decades of life. It occurs earlier in patients with polyposis syndromes.
Male:female ratio 1:1. Rectal tumors are more common in males.
The risk of tumor is increased with:
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High fat diet.
Decreased consumption of vitamins C,A, and E.
Low vegetable diet.
Low fiber diet.
Existence of polyposis syndromes.
Villous polyp.
Grossly the tumor may be ulcerating, fungating and polypoid or constricting, annular and circumferential.
Microscopically appear as adenocarcinoma and shows various degrees of differentiation. Some tumors may produce extensive extracellular mucin. In such cases the neoplastic glands reside within pools of mucus (colloid or mucinous adenocarcinomas). Some tumors may appear as signet ring carcinomas. Some tumors may exhibit carcinod features and some show squamous differentiation.
May be asymptomatic for years. May present as rectal bleeding, iron deficiency due to gradual loss of blood, fatigue, abdominal discomfort or pain to bowel obrstruction. May first present with hepatomegaly due to presence of metastasis.
Prognosis depends on the extent of invasion. Five year survival is as follows: Stage A, 100%, Stage B1 (67%), Stage C1 (43%), Stage C2 (23%).