Investigations;Investigations;

1- Sigmoidoscopy should be performed in all cases where blood & mucous have been passed.

2- Colonoscopy, either short (60 cm) flexible colonoscopyis done which need minimal bowel preparation (by immediate disposable enema) or by using total colonoscopy which need complete bowel preparation & has the advantage of picking up the primary carcinoma & the synchronous lesions of the colon if present.

3- Radiography, barium enema shows a constant, irregular filling defect but negative X-ray finding will not exclude small carcinoma of the colon in patients with high suspicion of the disease.

CT examination: Contrast enhanced axial scans: An intraluminal, bulging soft tissue mass is visible in the ventral wall of the ascending colon (upper pictures-arrows). Distally the lumen is narrowed, the circular thickening of the mucosal wall is irregular, the adjacent fat is infiltrated

(lower pictures - arrows (

Colonography: An 'apple-core' lesion of the colon is visible as a well-demarcated, circular, 1.5 cm long, irregular narrowing (arrow).

Barium enema: A 6 cm long section of the recto-sigmoid region has irregular contour, narrowed lumen (1 cm) and filling defect (arrow).

EnterographyEnterography: : Multiple narrowing of the terminal ileum is visible Multiple narrowing of the terminal ileum is visible ((arrowarrow). ). The tumor The tumor

involves the cecum and the ascending colon involves the cecum and the ascending colon ((double arrowdouble arrow).).

4- Exfoliative cytology, is of valuable help in diagnosis of carcinoma colon cases when endoscopy is not available, & this need good & careful bowel preparation, here after 5-10 min. the returned fluid is collected & centrifuged & the sediment is prepared & stained & examined.

Treatment:Treatment:

Preoperative preparation;

I- when there is no intestinal obstruction,

1. The patient should receive blood to correct the anemia.

2. Mechanical preparation to cleans the bowel by using;

1. Strong purgatives.

2. Whole bowel irrigation.

3. Enemas or combination of the above

3- High caloric & low residue diet.

4- Chemical preparation, by using metronidazole (flagyl) to deal with anaerobic microorganisms in conjunction with gentamycin or by using third generation cephalosporins.

II- When there is intestinal obstruction a preliminary drainage of the intestine proximal to the obstruction must be performed especially in cases of Lt. Side colonic cancer.

In cases of Rt. Side lesions a primary resection + end to end ileo-colic anastomosis is done.

Tests of operability; at opening the Tests of operability; at opening the peritoneal cavity the operability should be peritoneal cavity the operability should be seen at first by;seen at first by;

1. Palpating the liver for secondary metastasis.

2. Neoplastic implantation in the peritoneum especially the pelvic peritoneum.

3- Variant groups of lymph nodes that drains the involved segment, although their enlargement will not necessarily mean neoplastic invasion.

4- Fixity of the tumor to the underlying structures.

The operations to be described are designated to remove both the primary lesion as well as the loco-regional lymph nodes.

Types of operations;Types of operations;

1. Rt. Hemicolectomy treats carcinoma of the cecum or the ascending colon.

2. Carcinoma of the hepatic flexure, the resection here is extended Rt. Hemcolectomy to involve the transverse colon & splenic flexure also.

3- Carcinoma of transverse colon, by excision of transverse colon + both flexures together with greater omentum is the operation of choice.

4- Carcinoma of the splenic flexure or descending colon is treated by removing the transverse colon & the segment involved by tumor.

5- Carcinoma of pelvic colon, treated by Lt. Hemicolectomy.

With each type of the above operation the continuity of the bowel is restored by end to end anastomosis + putting drain down to the site of anastomosis.

Post-operative care includes;Post-operative care includes;

1. Administration of antibiotics.

2. Free fluids are not given by mouth after anastomosis until flatus is passed.

In cases of inoperable carcinoma of the colon, a proximal colostomy is done in case of tumor of pelvic or descending colon, while ileo-transverse

Anastomosis is done to by pass the obstructive tumor in case of carcinoma of ascending colon or the cecum.