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What is Commonest site of carcinoma colon is: and explain in detail?
(Left side colon): Ref: 1177-LB (1181-B &L 25th)Adenocarcinoma of the colon: - Tumours are more common in the left colon and rectum* Microscopically the neoplasm is a columnar cell carcinoma* Macroscopically the tumour may take one of four forms (Annular, Tubular ulcer, cauliflower/ Type 4 cauliflower is the least malignant form* All carcinoma starts as benign adenoma, the so called "adenoma-carcinoma sequence"* Annular variety gives rise to obstructive symptoms and where as the others more commonly will present with bleeding.Symptoms and signs of colorectal cancer(A) Right sided tumours: Iron deficiency anemia, abdominal pain(B) Left sided tumours: Rectal bleeding, alteration in bowel habit, tenesmus obstruction(C) Metastatic disease: Jaundice, ascitis, hepatomegaly, other symptoms and signs from rare sites of metastasis.