Colorectal Surgery Lecture Notes PDF

Lec. 5: Colorectal surgery Radwan A. Torky, MD Lecturer of general and colorectal surgery Diverticular disease of the colon Definition: Diverticulum: is defined as a saclike protrusion in the colonic wall that develops as a result of herniation of the muco...

Lec. 5: Colorectal surgery Radwan A. Torky, MD Lecturer of general and colorectal surgery Diverticular disease of the colon Definition: Diverticulum: is defined as a saclike protrusion in the colonic wall that develops as a result of herniation of the mucosa and the submucosa through "points of weakness" in the muscular wall of the colon. Diverticulosis: the presence of multiple diverticula with absence of symptoms. Prevalence: Diverticulosis is most prevalent in industrialized western countries. Prevalence is increased with advancement of age (5-10% before 50 years, 30% after 50 years, 50% after 70 years, 66% over age of 85 years). Common in western countries & less common in Egypt caused by chronic constipation due to low fiber diet 1|Page Etiology and pathogenesis: There are several factors implicated in pathogenesis of colonic diverticulum: 1. Low residue diet ( diet low in fibers) : cause muscle incoordination of colon and spasticity results in series of contracted rings represent as closed pockets with increase intraluminal pressure inside resulting in herniation of mucosa and submucosa through point of weakness ( site where blood vessels penetrate wall at lateral intertaenia area or less commonly at antimesenteric intertaenia areas). 2. Weakness and loss of compliance of colonic muscle wall: It occurs with advancement of age. Pathology: Site: common in sigmoid colon (90%) due to the thickening of the muscular layer, shortening of the taeniae, and luminal narrowing making contracted ring obliterates lumen completely with very high intraluminal pressure in intervening pocket. Rare in right side colon and rectum as they have more compliance than left side colon. Rectum never be affected Complication: 1. Diverticulitis: due to stagnation of content and secondary infection. 2. Perforation: cause either localized pericolic abscess or generalized fecal peritonitis. 3. Fistula external..... colocutaneous fistula may be a complication of pericolic abscess drainage. internal fistula..... as colovesical fistula (the commonest type due to proximity of bladder to sigmoid, common in male as uterus is protective in females) , colovaginal fistula, or coloenteric fistula. 4. Intestinal obstruction: due to recurrent episodes of inflammation cause fibrosis and stenosis. 5. Lower GIT bleeding: massive bleeding in 5% of cases usually stop spontaneously in 80% of cases. It is due to rupture of vasa recta at dome or neck of diverticula as the result of proximity of circular arteries to diverticula. Clinical picture: A) Uncomplicated colonic diverticulosis: majority of cases are asymptomatic. Small proportion of patients may have symptoms difficult to be distinguished from irritable bowel syndrome: 2|Page  Symptoms: colicky abdominal pain, bloating, flatulence, and altered bowel habit. Signs: tenderness in the left iliac fossa with no signs or symptoms of peritonitis or systemic illness, and all laboratory values may be within normal limits. B) Complicated colonic diverticulosis: 1. Symptoms : Lower abdominal pain (on left side in sigmoid I. Uncomplicated diverticulitis and right side in right colon diverticulitis: diverticulitis or in redundant sigmoid colon laying in right side). GIT disturbance : altered bowel habit (constipation alone or alternating with diarrhea), nausea, vomiting, anorexia. Urinary symptoms : such as dysuria, frequency, and urgency probably caused by the proximity of the bladder to the inflamed sigmoid colon in minor cases. Fever almost present, high fever suspects advancement of disease and spreading of sepsis in peritoneal cavity. 2. Signs: rigidity and tenderness in left iliac fossa (left side appendicitis ). 1. Pericolic abscess..... localized tender abdominal mass. 2. Generalized peritonitis.... generalized tenderness, rigidity, guarding, absent intestinal sound and free gas in plain erect on abdomen. 3. Colovesical fistula..... frequency, pneumaturia and II. Complicated fecaluria and diagnosis is confirmed by barium enema, diverticulitis : cystoscope, cystography. 4. Colovaginal fistula.... fecal vaginal discharge. 5. Coloenteric fistula.... recurrent episodes of enteritis due to colonization of small intestine. III. Intestinal Small or large bowel obstruction (partial or obstruction: complete ) presented with distention, vomiting, constipation. Investigation: 1. Barium enema examination: (saw tooth apperance/ diverticulae) it should be avoided in acute inflammation for fear of perforation. It may reveals one or more of following signs 3|Page  a) Multiple globular shadow in relation to colon. b) Fistulous tract between colon and internal organ. c) Colonic stricture as result of fibrosis and stenosis which differentiated from malignant stricture as the following : Diverticular disease Cancer Long segment stricture Short segment stricture Normal bowel tapers gradually in Abrupt termination of normal stricture bowel in stricture. Preserved mucosa Destructed mucosa Probanthin results in relaxation Has no effect 2. Colonoscopy: it is better to be delayed till recovery from active inflammation to avoid risk of perforation. It is useful in cases complicated with bleeding to identify site of bleeding and excludes other causes as angiodysplasia or colorectal cancer. 3. Ultrasound and computed tomography : CT scan (in acute stage, stricture, mass, abscess and CV fistula) helpful to diagnose pericolic , pelvic or retroperitoneal abscess. 4. Scintography and mesenteric angiography : (in cases of bleeding ) used in case of lower GIT bleeding to identify site of bleeding. Angiography is used if rate of active bleeding 1ml\ minute, Scintography is used if rate of active bleeding 0.1ml\ minute. 5. Plain radiography on abdomen: detect free gas in case complicated with perforation and fluid level in case of obstruction. 4|Page Differential diagnosis: 1. Irritable bowel syndrome 4. Pelvic inflammatory disease, 2. Ischemic colitis endometriosis and urologic problems 3. Infectious colitis 5. Appendicitis, cholecystitis 6. Colorectal cancer Treatment: A.Treatment of symptomatic uncomplicated diverticulosis : 1. Dietary modification : increase diet rich in fibers as wheat bran, vegetables and fruits 2. Drug therapy : anti spasmodic ✓ Stool bulking agents as methycellulose, isogel, fabogel, normacol. ✓ Mebeverine hydrocloride.... causes direct smooth muscle relaxation. B.Treatment of complicated diverticulosis : 1. Acute uncomplicated diverticulitis: usually responds to conservative treatment with rapid clinical improvement and resolution of fever, pain, ileus within 48 to 72 hours. 2. Treatment of complicated diverticulitis: a) Conservative treatment: admission, NPO. N\G suction, bed rest, IV fluid, antibiotics, flagyl and avoid enema and purgatives. b) Percutaneous CT guided drainage : indicated in increased size abscess or failure of conservative treatment to improve condition within 48 hours. c) Surgical treatment: surgical drainage of abscess and proximal colostomy is indicated in abscess not amenable to CT guided drainage or persistence of symptoms and signs of peritonitis. Treatment: 1. Non complicated cases: High fiber diet, anti spasmodic 2. Complicated cases: A. Acute diverticulitis (admission, bed rest, AB) Abscess (per cutaneous / surgical drainage) perforation (resuscitation, laparotomy & lavage then Hartmann colostomy CV fistula (resection and repair) B. Chronic diverticulitis: Elective colectomy C. Bleeding per rectum: ✓ Resuscitation then angiography ✓ accurate localization (resection) ✓ failed localization (total colectomy) 5|Page  d) Urgent laparotomy in cases of peritonitis: Preoperative resuscitation: using IV fluid, antibiotics, NG suction, cardiovascular support. Surgical options: depends on degree of contamination, time of surgical intervention and general condition of the patients: - Single-stage procedure: Primary resection and anastomosis without protective stoma is indicated in patients with minimal peritoneal contamination. - A two-stage procedure: is commonly indicated for patients with substantial fecal contamination. ✓ Hartmann's procedure: initial resection of the diseased segment and brought out proximal stump as stoma and close distal stump followed later by elective restoration of the intestinal continuity ✓ Resection and primary anastomosis with performing a proximal protective stoma that closed at a later appropriate time. Inflammatory bowel disease (IBD) (chronic ulcerative colitis) Etiology : unknown, may explained by different theories : 1. Genetic theory : 2. Immunological theory : 3. Infectious theory : ✓ Bacterial allergens may induce abnormal immunological response. 4. Allergic theory : Cow milk sensitivity.( milk free diet is benefit ). 5. Emotional theory : some cases may relapse after exposure to stress. N.B. : appendectomy and smoking were found to be protective against U.C. Pathology : Site of affection: rectum is involved in most of cases (95% ) , and there are different varieties : 1. ulcerative proctitis ( localized to rectum ). 2. ulcerative proctosigmoiditis. 3. ulcerative left side colitis. 4. ulcerative subtotal colitis. 5. ulcerative pancolitis. 6. black wash ileitis (terminal ileum is involve10%) 6|Page  Pathology: commonly affecting the rectum (left colon or the whole colon) rarely affecting the terminal ileum (backwash ileitis) mucosal edema or extensive ulcerations with no skip lesions. microscopically: cryptitis, crypt abscess and pseudopolyps. Macroscopic picture : It is diffuse inflammatory disease, lesions is confluent, not segmental (no skip lesion). Lesion is confined to mucosa and lesser extent to submucosa (rare involve musculosa and serosa). ✓ multiple ulcers in mucosa with pseudopolyps and mucosal bridging ✓ ulcers may extend to submucosa cause reflex spasm of muscles and intramural fibrosis. Fulminant case (toxic megacolon): muscles and serosa are involved and colon may complicate with dilatation and perforation. Microscopic picture : 1. Active stage : 2. Remission: 3. long standing case : - crypt epithelium inflammation-- normal histological finding a) Hypertrophy of muscularis -- crypt abscess----- necrosis of with evidence of: mucosa. crypt epithelium and chronic a) mucosal atrophy b) Paneth cells hyperplasia. inflammatory cells infiltration in b) decrease number of c) Dysplasia may occurs ( submucosa----- rupture of colonic glands (shortened precancerous ). abscess in mucosa---- ulcers &branched ) covered by vascular granulation tissues. Clinical picture: Cardinal symptoms: 1. watery diarrhea with mucous, pus, blood and may associated with tenesmus, urgency or even incontinence. 2. Rectal bleeding. 3. Abdominal cramping pain. 4. Variable degree of systemic symptoms : fever, vomiting, loss of weight, dehydration Clinical picture: 1. Abdominal pain, bloody diarrhea, mucorrhea. 2. weight loss and dehydration. 3. picture of complications: (toxic megacolon): severe exacerbation of symptoms, 7|Page  hyperpyrexia 39 - 39.5"C severe toxicity Severe abdominal distension Fatal condition with bad prognosis Investigation : 1. Endoscopy and biopsy : to confirm diagnosis. Contraindication: in severe case------ risk of perforation. Finding: - diffuse lesion usually involve rectum and extend proximally with absence of segmental lesion, granular mucosa with tiny ulcers and intervening mucoa may shows pseudopolyposis. 2. Barium enema: irregular serrated bowel contour. multiple filling defect (pseudopolyposis). loss of haustration (lead pipe appearance ). 3. Microbiological examination of stool: to exclude infectious causes of colitis 4. colonoscopy and biopsy 5. anemia or leukocytosis in acute cases Complications: 1. Toxic megacolon : Pathology: a) usually occurs in extensive type and transverse colon & splenic flexure are predominant involved. b) transmural extension of inflammation and ulcers---- destruction of muscles loss of peristalsis and thining of wall---- dilatation ------ risk perforation. 8|Page  Clinical picture: - history of bloody diarrhea. - severe distented abdomen and absent intestinal sound. - Systemic manifestation : fever ,tachycardia, dehydration, leucocytosis. - Features of complication: peritonitis due to perforation. Investigation: plain X ray: - dilated colon ( 10-12 cm ). - loss of haustration and mucosal abnormalities. - Sometimes, intramural air Treatment: A) conservative: B) surgical : 1. urgent hospitalization of the Indication: patients 1. failure of conservative treatment 2. Frequent monitoring of patient: within 72 hours 3. Nasogastric suction 2. occurrence of perforation. 4. NPO Procedures: Colectomy with ileostomy 5. IV fluid and bring rectal stump as mucous fistula. 6. Blood transfusion. 7. IV corticosteroid ( hydrocortisone 100-200mg every 6 hours ). 2. colonic perforation : Causes: - toxic megacolon. – use of barium enema or endoscope in active disease. Clinical: features of peritonitis with rapid deterioration and septic shock. Plain X ray: free gas in abdomen. 3. Massive hemorrhage : it occurs in severe extensive type ,may be associated with DIC and usually respond to conservative treatment and blood transfusion. 4. Colonic stricture : with incidence 5-10%. It is either fibrotic stricture or due to mucosal hyperplasia ( reversible ). colonoscope and biopsy are needed to exclude malignancy. 5. Colonic cancer : Incidence: it depends on duration of diseases : 1% at 10 years duration, 5% at 20 years and 10% at 25 years. Character: - usually occurs in extensive total type. - younger age than non colitis patients. 9|Page  -Usually affect right colon. - Less well differentiated, small, flat, multicenteric tumor. Endoscopic surveillance is required in long standing extensive type to detect early malignant changes. Presence of dysplasia is an indication of prophylactic colectomy. Extracolonic manifestation Of U.C. : 1. Eye: uveitis 2. Joint : spondylitis, arthritis (large joint). 3. Skin: erythema nodosum, pyoderma gangrenosum 4. Liver: fatty changes, cirrhosis, cholangiocarcinoma, sclerosing cholangitis Treatment : A) medical treatment : Rest and diet control (high protein & low residue diet) Anti-inflammatory drugs: 1. Sulphasalazine : combination of 5ASA and sulphapyridine. 2. Mesalazine : coated tablets of 5ASA slowly release their contents into distal bowel and colon. It has advantage of fewer side effect than sulphasalazine. ( nephrotoxic, watery diarrhea ). 3. Prednisolone: 1-2mg /kg / BW /day ( maximum 40-60 mg ) for 2-3 weeks then gradual withdrawal to 5-10mg /day. 4. Immunosuppressive drugs : Azathioprine + 6 mercaptopurine or cyclosporine A or methotrexate 5. other agents : anti TNF antibody, heparin, cyclosporine like drugs 6. dietary folic acid supplementation decrease risk of development of cancer in long standing cases. B) Surgical treatment : Indication : I) Emergent indication : 1. severe ulcerative colitis not respond to medical treatment for 5-7 days 2. occurrence of acute complications : toxic megacolon ( not respond to treatment within 72 hours ), perforation, massive hemorrhage. II) Elective indication : 1. Intractable disease i.e. frequent exacerbation, chronic continuous type resulting in disability to work, social & sexual life. 2. Severe extracolonic manifestations. 3. Occurrence of chronic complications : developed dysplasia or cancer. 10 | P a g e  growth retardation in child. colonic stricture or fistula. Procedures : 1. Total colectomy with ileostomy and rectal preservation: 2. Total colectomy with ileorectal anastomosis: 3. Total proctocolectomy with ileostomy 4. Total proctocolectomy with ileoanal pouch(restorative proctocolectomy) Pseudo membranous colitis It is caused by C. difficile (g +ve anaerobic bacillus). It is the leading cause of nosocomially acquired diarrhea. It is due to the overgrowth of C.difficile after depletion of the normal flora of the gut with the use of antibiotics. Clindamycin was the first antimicrobial agent associated with C. difficile colitis however almost any antibiotic may cause this disease. Immunosuppression, medical comorbidities, prolonged hospitalization or nursing home residence, and bowel surgery increase the risk. Diagnosis: the disease is caused by production of toxin A and B. stool culture will show the organism. detection of toxins by immunoassay colonoscopy will show ulcers, plaques and pseudomembranes Treatment: 1. Immediate cessation of the offending antimicrobial agent. 2. oral metronidazole in mild cases. 3. Oral vancomycin in recurrent disease. 4. Hospital admission and resuscitation in severe cases. 5. Reintroduction of normal flora by stool transplantation for refractory disease. 6. total abdominal colectomy with end ileostomy in cases of perforation 11 | P a g e  Rectal prolapse Definition: An abnormal descent of part or all of the upper rectum through the lower rectum and/ or the anal canal to protrude outside the anus. Types: 1.Partial 2.Complete Partial prolapse Complete prolapse definition Prolapse of rectal mucosa Prolapse of the whole rectal layers causes 1. Loss of weight. It is more common in females 2. Prolonged diarrhea due to 1. Repeated diarrhea straining). 2. C.T. disease due to 3. Advanced hemorrhoids defective collagen synthesis (grade lll, lV). 3. Lack of fixation between the 4. BPH due to continuous rectum and sacrum. straining. 5. Sphincteric atony in the elderly. 6. Iatrogenic sphincter injury during fistula surgery Length < 5 cm > 5 cm Thickness Mucosa only Whole rectal layers 1. Ulceration & infection 2. bleeding complications 3. irreducibility 4. strangulation 5. fecal incontinence 6. anal discharge 12 | P a g e clinical picture: 1. Something protruding from the anus 2. picture of complications 3. mucosal discharge 4. best seen in squatting position during straining 5. DRE for the tone of the sphincter, prolapse thickness and floor Trans abdominal rectopexy Investigations 1. MRI defecography (show the state of the pelvic floor, hidden prolapse, rectocele) 2. Anorectal manometry show the resting pressure, squeeze pressure or incontinence 3. Sigmoidoscopy to exclude any underlying lesions. Treatment: I. Children: II. Adults: a) Correct the predisposing factor a) Correct the predisposing factor b) Digital reposition b) sphincter exercise. c) Submucosal injection of a sclerosant c) Surgery: various surgical procedures: agent (induce fibrosis) Trans abdominal rectopexy: (open vs lap., d) Thiersch operation (perianal cerclage) ant vs post., mesh vs suture) e) Excision of redundant mucosa Trans perineal resection: Delorme op., Altemier op. Colorectal polyps Classifications: Classification of Benign Intestinal Polyps Type Solitary Multiple Neoplastic - Adenoma (tubular, - Familial adenomatous tubulovillous, villous) polyposis (FAP) - Juvenile polyposis syndrome (JPS) - Juvenile polyp - Peutz–Jeghers Hamartomatous - Peutz–Jeghers polyp syndrome (PJS) - Cronkhite–Canada syndrome - Cowden’s disease 13 | P a g e  - Benign lymphoid Inflammatory - Benign lymphoid polyp polyposis Pseudopolyposis in ulcerative colitis - Metaplastic - MYH-associated Metaplastic (hyperplastic) polyposis (MAP) - Serrated adenoma Multiple metaplastic polyps 1. Peutz jegher syndrome: An autosomal dominant disease Characterized by: a) multiple polyps in the stomach, small intestine and colon b) melanotic pigmentations of the skin and mucous membranes. c) may cause abdominal. distension, colic or intussusception d) low rate of malignant transformation (< 2%) 2. Familial adenomatous polyposis (FAP) Etiology: autosomal dominant disease (APC gene mutation) males = females Gardner’s syndrome = FAP + desmoid tumors, osteochondroma & sebaceous cysts Pathology: the rectum and sigmoid are commonly affected they are full of multiple polyps (> 100) clinical picture: - Positive family history - Diarrhea, bleeding per rectum and abdominal pain. - Intestinal obstruction due to intussusception. - CRC develop in 100 % of patients Investigations: 1. Barium enema (multiple filling defects) 2. colonoscopy and biopsy 3. screening for the whole family Treatment : The surgical procedures are similar to those for U.C 14 | P a g e  Colorectal cancer: Epidemiology: usually above 50 years but younger ages may develop cancer. cancer cecum is more common in females predisposing factors: low fiber & high fat diet smoking & alcohol UC (> 10 years) villous adenoma > 2 cm FAP & Gardner syndrome HNPCC Risk Factors for Colorectal Cancer: Hereditary CRC Syndromes a) Adenomatous polyposis syndromes ✓ Familial adenomatous polyposis (FAP) ✓ MYH-associated polyposis (MAP) b) Nonpolyposis syndrome ✓ Hereditary nonpolyposis CRC (HNPCC) c) Hamartomatous polyp syndromes ✓ Peutz-Jeghers syndrome (PJS) ✓ Cowden disease (Bannayan-Ruvalcaba- ✓ Juvenile polyposis syndrome (JPS) Riley) Inflammatory Bowel Disease: Ulcerative Colitis Personal History of CRC Family History of CRC Ethnic background: Ashkenazi Jews Age: - above 50 years in the western community. - In Egypt the median age of CRC less than 50 years Environmental Factors Increased risk of CRC with a diet high in: 1. Red meat and animal fat 2. Low-fiber diet: low overall intake of fruits and vegetables Lifestyle choices that are associated with increased risk for CRC: 1. Alcohol and tobacco consumption 2. Obesity 15 | P a g e  3. Sedentary habits Factors associated with lower risk include: 1. Folate intake 3. Estrogen replacement therapy 2. Calcium intake Pathology: 1. site: 2/3 of cases are situated in the rectum and sigmoid colon. Transverse colon is the least common affected site. multi-centeric tumors occur in 5 % 2. Gross types: Annular infiltration : causes obstruction Ulcerative : most common, especially in the left side. Cauliflower: least malignant, usually in the right side. 3. Microscopic types: ✓ Adenocarcinoma. ✓ Colloid carcinoma. ✓ Anaplastic carcinoma. ✓ Malignant melanoma (rectum) ✓ Carcinoid, lymphoma, GIST. Clinical Picture of Primary Colorectal Cancer The most common presenting symptoms associated with colon cancer are abdominal pain, followed by change in bowel habits, rectal bleeding, and occult blood in the stoo Cancer Right Colon Cancer Left Colon Cancer Rectum 1. Change in Bowel Habits 1. Change in Bowel Habits 1. Bleeding /Rectum 2. Diarrhea 2. Increasing Constipation 2. Mucous/ Rectum 3. Pain 3. Pain 3. Tenesmus (Sense of incomplete 4. Vague upper abdominal 4. Colicky with distension evacuation) 5. Iron Deficiency Anemia 5. Weight Loss 4. Change in Bowel Habits 6. Weight Loss 6. Mass (advanced or fecal 5. Spurious morning diarrhea 7. Mass (advanced ) matter) 6. Pain 8. Obstruction Rare 7. Obstruction common or 7. Colicky in rectosigmoid lesions 1st presentation 8. Severe pelvic (advanced due to 8. Bleeding /Rectum infiltration) 9. Mucous/ Rectum 9. Weight Loss 10. Rare Obstruction in rectosigmoid lesions 16 | P a g e  Symptom Rt. Side Lt. Side Rectum Change in Bowel Habits Constipation Diarrhea Constipation spurious morning diarrhea Bleeding /Rectum Altered Dark Fresh Colicky Pain + ++++ upper 1/3 Mass +++ ++ - Mucous/ Rectum - + ++++ Tensmus Incomplete - - +++++ Evacuation Weight Loss +++ + ++ Iron Deficiency Anemia ++++ + + 17 | P a g e Clinical Picture 1. Non-Obstructed: Cecum & right colon cancer: 1. Loss of weight and chronic anemia 2. hard mass in right iliac fossa 3. appendicitis like pain especially in old age Left colon cancer: 1. Change in bowel habits 2. bleeding per rectum 3. colicky lower abdominal pain 4. Rarely presented by a mass in the left iliac fossa rectal & rectosigmoid cancer: 1. Slight bleeding per rectum 2. Tenesmus & sometimes bladder symptoms 3. painless mass (may be associated with 2 ry hemorrhoids) 4. DRE reveals mass within 10 cm from the anal verge 2. Obtructed: Commonest with left sided cancers, rare with other types. Progressive constipation, distension and colicky lower abdominal pain. ln the right side: May obstruct the ileocecal valve and terminal ileum. Spread of Colorectal Cancer 1. Direct spread Intramural ✓ Circumferential ✓ Longitudinal Transmural 2. Lymphatic spread 3. Venous spread: Liver & Lung metastases 4. Transperitoneal spread : -Malignant ascites -Krukenberg’s tumor 18 | P a g e Complications of Colorectal Cancer: 1. Intestinal obstruction 2. Penetration (fistula) 3. Bleeding (anemia or hypovolemia) 4. Intussusception: incomplete obstruction 5. Perforation: ✓ Tumor perforation ✓ Caecal perforation caused by a left-sided colon cancer Grading of CRC : it depends on glandular structure formation, nuclear pleomorphism and frequency of mitosis. It is : - Grade I: well differentiated (best prognosis) - Grade II: moderate differentiated (fair prognosis) - Grade III: poor differentiated (poor prognosis) - Mucoid tumors: (worst prognosis) Investigation : A) Endoscopic diagnosis : it is the gold standard practice for diagnosis of CRC. Advantages : 1. visualise tumors and takes biopsy for histopathology. 2. diagnose or exclude the presence of synchronous tumors (7%) or polyp 3- follow up high risk patients. 3. postoperative follow up metachronous tumors (10%) or anastomotic recurrence. 4. valuable for symptomatic patients with normal Barium enema. 5. resolves the radiological misinterpretation at caecum &sigmoid B) Barium enema : it is better to use double contrast enema with high degree of accurracy specially for tumors limited to mucous membrane as it delineates the wall. Values : 1. it shows CRC : a. Annular: apple core deformity. b. Polypodal: filling defect 2. diagnose the associated synchronous tumors or multiple adenomatous polyps. C) Staging investigation : 1) Endosonography : ERUS is considered the most accurate methods for staging of cancer rectum with values of : 19 | P a g e  - Determines the degree of local invasion of the tumor through rectal wall with accuracy (60-90% ) by examining five layers. - Determines regional L.Ns invasion with accuracy 80% ,it appears as hypoechoic round lesion in mesorectum. 2) CT & MRI : they are valuable for detection of local spread , L.Ns metastasis and liver metastasis with accuracy 70 %. 3) Abdominal Ultrasonography for detection liver metastasis. ( intraoperative contact US is more sensitive & accurate. ) 4) Pyelography &cystoscopy if the patients have urinary symptoms. D) Investigation for follow up & prognosis : Carcinoembryonic antigen : It is a glycoprotein present normally in embryonic and fetal tissues ,not in normal adult colonic mucosa. It is elevated in CRC but not specific as elevated also in smokers, crohn's disease, U.C, alcoholic cirrhosis, renal disorders and malignancy of prostate, breast, bronchus, ovary, pancreas & GIT. So it is not used as a diagnostic but as a prognostic after surgery Staging system for CRC : 1) TNM staging 20 | P a g e  2) Modified Dukes staging system A tumor is limited to submucosa B1 tumor invades but not penetrates muscularis. B2 tumor invades serosa not adjacent organs. B3 tumor invades adjacent organs C1 B1 + regional L.Ns metastasis. C2 B2 + regional L.Ns metastasis. C3 B3 + regional L.Ns metastasis. D distant metastasis Treatment of colorectal cancer Treatment of cancer colon: A) Operable colon cancer: radical removal of tumors include : Surgical options: 1. Right hemicolectomy: Indication : cancer caecum and ascending colon. Complication: duodenal and ureteric injuries. 2. Extended Right hemicolectomy : Indication : cancer hepatic flexure. 3. Transverse colectomy : Indication : tumor of middle transverse colon. 4. Left hemicolectomy : Indication : cancer of descending colon. 5. Extended left hemicolectomy : Indication : cancer of splenic flexure. 6. Low anterior resection : indication : cancer sigmoid and proximal rectal lesion. 7. Subtotal colectomy: Indication: o multiple synchronous tumors o family cancer syndromes o 2ry primary cancer colon. 8. Total proctocolectomy: with ileostomy or ileal pouch anal anastomoses: in patients of cancer colon with history of FAP. 9. Laparoscopic colectomy: it is widely used nowadays in the treatment of CRC with the same principles of open approach. 21 | P a g e  Advantages : 1- safe, technically feasible 2- less morbid 3-short hospital stays. 4- rapid recovery. Adjuvant therapy: it is used postoperative after potential curative resection of cancer colon. B) Inoperable colon cancer : Criteria of inoperability : a) General: unfit patients large or multiple liver metastases disseminated cancer colon b) local: irresectable cancer. paraortic L.Ns involvme 1. Surgical treatment : ✓ Resectable : palliative resection. ✓ Irresectable : palliative bypass : a. Right side cancer colon: ileotransverse bypass anastomoses. b. Left side cancer colon: diverting colostomy. 2. palliative chemotherapy :.aim to prolong and improve quality of life. 3. Palliative radiotherapy. C)Treatment of obstructed colon cancer : Acute intestinal obstruction is the common emergency presentation of cancer colon which carry bad prognosis. 1. obstructed right cancer colon : is uncommon. if respectable: a. patient fit : radical right hemicolectomy with primary anastomosis in one stage. b. patient unfit: diverting stoma followed by 2nd stage of resection and anastomoses when the patient improved. if irresectable : palliative ileotransverse bypass. 2. obstructed left cancer colon : is common. if resectable : A) 3 stages procedure : ✓ 1st stage----- diverting colostomy. ✓ 2ndstage----resection and anastomoses. ✓ 3rd stage---- closure of colostomy. B) 2 stages procedure (Hartmann operation ) ✓ 1st stage-----resection of affected segment and brought proximal end as end colostomy and close distal end 22 | P a g e  ✓ 2nd stage---- restore the continuity by end to end anastomoses. 3- one stage procedure : intraoperative colonic lavage and segmental resection with primary anastomoses. if irresectable : palliative transverse or pelvic colostomy. Treatment of cancer rectum : neoadjuvant chemoradiotherapy followed by surgery: A) Operable cancer rectum : Radical resection : Types of radical resection procedures: 1) upper third rectal cancer: Resection and anastomosis between descending colon and middle third rectum. (Anterior Resection or Low Anterior Resection) 2) Middle and lower third rectum down to > 2 cm from the dentate line Proctectomy with anastomosis between descending colon and anal canal (coloanal anastomosis) = Ultra-Low Anterior Resection 3) Abdominoperineal resection: Indications : 1. Low cancer rectum located 0-3cm from anal verge. 2. Cancer rectum with involvement of sphincters or levator ani. 3. low cancer rectum with large poor differentiated tumors 4. Cancer rectum with involvement of adjacent pelvic organs 5. Cancer rectum in patients with primary sphincter dysfunction or incontinence. Procedure : Removal of the anorectum and lower ¾ of sigmoid colon with the establishment of permanent left iliac colostomy 23 | P a g e