COLON James Taclin C. Banez, MD Anatomy / Physiology: • • Location, blood supply & venous drainage, lymphatic drainage and nerve supply Function: • absorption of fluid and electrolyte • Transport and temporary storage of feces Anatomy / Physiology: Infectious: 1. Amebic colitis: Entamoeba histolytica Primary – colon : secondary – liver Fecal to oral route: (sexual contact, contaminated water & food) Abdominal pain, bloody diarrhea, tenesmus, fever Complication: megacolon / colonic obstruction (partial) ---> AMEBOMA – mass of inflammatory tissue Dx: clin hx / stool exam / indirect hemagglutination test Tx: metronidazole / iodoquinol : rare COLECTOMY Pseudomembranous colitis: 2. Complication of antibiotics ---> alteration of normal flora • Overgrowth of Clostridium deficile: • Has cytopathic and enteropathic toxins Develops 6wks after: • a. b. c. Dx: Clindamycin Ampicillin Cephalosporin - history - latex fixation test - colonoscopy (Pseudomembrane) Tx: 1. stopped antibiotic ----> metronidazole/vancomycin 2. cholestyramine ---> binds w/ toxin 3. Toxic megacolon---> total colectomy w/ ileostomy 3. Salmonellosis: Salmonella typhi (typhoid fever) Dx: perforation / bleeding Tx: antibiotic / transfusion / right hemicolectomy w/ or w/o ileostomy 4. Actinomycosis: A. israeli (gm + anaerobic or microaerophilic bacterium) • Characteristic: - chronic inflammatory induration and sinus formation • Cervicofacial area most frequent site • Abdomen – involves the cecum after AP Tx: surgical drainage and antibiotic (penicillin/ tetracycline) Volvulus: Twisting of an air-filled segment of bowel about its narrow mesentery ---> OBSTRUCTION -------> STRANGULATION ----> GANGRENE----> PERFORATION ----> PERITONITIS SIGMOID VOLVULUS (90%): • 1. Redundant sigmoid colon w/ a narrow based mesocolon Sx: colicky abd. pain, distention obstipation, rectal collapse s/sx of dehydration • Volvulus: SIGMOID VOLVULUS (90%): 1. Dx: FPA – inverted U • • shaped sausage like loop (diagnostic) Barium enema – bird beaks deformity Gangrene – chills/fever, leukocytosis w/ s/x of peritonitis 1. SIGMOID VOLVULUS (90%): Tx: (-) Signs of Peritonitis: Reduced the volvulus --->prepare for elective colonic surgery for the recurrence is 40%: - use of flexible scope (+) Signs of Peritonitis / Unsuccessful reduction: Sigmoidectomy w/ Hartmanns or Divine’s colostomy 2. Cecal Volvulus: Tx: reduction is impossible --> emergency exploration (+) Gangrene: - right hemicolectomy - end to end ileo-transverse colostomy (-) Gangrene: a) – same – b) Cecopexy c) Pure detorsion (recurrence 7 – 15%) 3. Transverse colon volvulus: Rare, due to it’s broad based and short mesentery Tx: resection of redundant transverse colon DIVERTICULOSIS: Abnormal pouch from the wall of a hollow organ Types: 1. 2. True diverticula (rare) – right side False diverticula (common) – due to low fiber diet: left side Rare before 30y/o; common > 75 y/o Female > Male Etiology: 1. Unknown 2. Theories by Painter et al: a) b) c) Contraction ring (thickening of circular muscle) Depletion of dietary fibers ---> narrow lumen Deteriorating integrity of the bowel wall; elderly has lower tensile strength, lowest in the sigmoid) DIVERTICULOSIS: Pathology: Site: arteriole penetrates the mesenteric side of the antimesenteric teniae coli: 1. Sigmoid (50%) 2. Descending colon (40%) 3. Entire colon (210%) DIVERTICULOSIS: Clinical Manifestation: A. B. Majority are asymptomatic Symptomatic patients: 1. Uncomplicated painful diverticular dse. (+) LLQ pain and tenderness; (+) change in bowel habits (-) rebound tenderness (-) fever nor leukocytosis Dx: Gastrografin enema Tx: high fiber diet 2. Complicated diverticular disease: a. Diverticulitis / Peridiverticulitis: Infected diverticula Diverticula is filled up ---> obstructed ---> mucus secretion and bacteria ---> inflammation at the apex ---> unresolved --> extend intramurally ---> perforate. 2. Complicated diverticular disease: a. Diverticulitis / Peridiverticulitis: Sx:- left lower abd. pain / chills & fever / bowel habit changes - (+) abd. Tenderness, distension if w/ partial obstruction - para-rectal tenderness - frequency / urgency of urination (inflamed bladder) 2. Complicated diverticular disease: a. Diverticulitis / Peridiverticulitis: Dx: 1) Cln. Hx. 2) Ct scan of the abd / utrasonography (thickened wall & abscess can be seen) 3) Contrast enema / sigmoidoscopy (risk of spreading infection) 2. Complicated diverticular disease: a. Diverticulitis / Peridiverticulitis: Tx: 1) NPO or liquid diet 2) Broad spectrum antibiotic 3) Meperidine (not morphine) 4) If improved endoscopy to r/o CA 2. Complicated diverticular disease: b. Perforated Diverticulitis: Sx: - similar to appendicitis (Phlegmon mass) - (+) pneumoperitoneum Classification of perforated diverticulitis (Hinchy) Stage I: abscess confined by mesentery of colon Stage II: pelvic abscess Stage III: generalized peritonitis Stage IV: fecal peritonitis 2. Complicated diverticular disease: b. Perforated Diverticulitis: Tx: initial none operative: - NPO / IVF / Broad spectrum antibiotic/ meperidine Stage I & II: (+) improvement elective Surgery (4 wks) (-) improvement percutaneous drainage (-) improvement ---> Surgery 2. Complicated diverticular disease: b. Perforated Diverticulitis: Stage III & IV: explore after initial resuscitation a. sigmoidectomy w/ primary anastomosis b. sigmoidectomy w/ Hartmann’s colostomy c. resection w/ primary anastomosis w/ proximal diverting stoma 2. Complicated diverticular disease: c. Obstructing diverticulitis: 90% partial – due to spasm, edema & ileus 10% complete – fibrosis and stenosis S/Sx: of large intestinal obstruction Tx: conservative mx (3-5 days) ---> (-) response ----> cecum dilates to 10-12 cm. ---> surgery. 2. Complicated diverticular disease: d. Acute hemorrhage: Due to erosion of the peridiverticular arteriole by inspissated stool w/in the diverticulum and thinning of the tunica media DIVERTICULOSIS: Clinical Manifestation: B. Symptomatic patients: 2. Complicated diverticular disease: d. Acute hemorrhage: Resuscitate the patient Locate the site of bleeding (Tc labeled RBC/selective arteriography) Vasopressin infusion, transcatheter emboli infusion using gelfoam Colonoscopy Tx: segmental resection / blind subtotal colectomy DIVERTICULOSIS: Clinical Manifestation: B. Symptomatic patients: 2. Complicated diverticular disease: d. Fistula formation: Bladder, vagina, small bowel, skin Dx: - clin hx & PE (pneumaturia, fecaluria and frequent UTI) - cystoscopy, IE, speculum exam - methylene blue enema - colonoscopy to r/o CA DIVERTICULOSIS: Clinical Manifestation: B. Symptomatic patients: 2. Complicated diverticular disease: d. Fistula formation: Tx: - bowel rest w/ TPN or elemental diet - Foley catheter (10 days postop) / antibiotic - placement of ureteral catheter prior to celiotomy - sigmoidectomy w/ primary anastomosis - fistulectomy and closure of secondary opening Hemorrhage from the Colon: 1. 2. Diverticular disease Angiodysplasia (Vascular ectasia, AV malformation, Angiectasia) ANGIODYSPLASIA Acquired lesion Proximal colon (cecum) where tension is greatest (Laplace’s law – tension in the wall is highest in the widest circumference) Rare < 40y/o; common in elderly Etiology: - chronic intermittent obstruction of submucosal veins due to repeated muscular contraction ANGIODYSPLASIA Dx: - Nuclear scan / angiography = (vascular tuft and early filling of veins) - colonoscopy = distinct red mucosal patch Management of Massive Lower GIB Bleeding distal to the ligament of Treitz: 1. 2. 3. 4. 5. 6. Diverticular disease Angiodysplasia Inflammatory bowel disease Ischemic colitis Tumor Anticoagulant therapy Gastroduodenal hge -> can present as rectal bleeding It is more important to identify the location of the BLEEDING POINT than the immediate diagnosis as the cause. Management of Massive Lower GIB Diagnostic: Nuclear imaging (bleeding scan/scintigraphy) 1. a. Technetium-Sulfur Colloid Scan b. Autologous labeled RBC scan 2. Sensitive (0.5ml/min) Stays in the circulation for as long as 24 hrs (monitoring) (1ml/min bleeding) Mesenteric Angiography Done once patient’s condition is stable and hydration is adequate Identify bleeding point ---> 1ml/min Could be therapeutic ---> Vasopressin/emboli Vascular taft (A) Early filling vein (B) Management of Massive Lower GIB Diagnostic: 3. Emergent colonoscopy: Possible w/ use of GOLYTELY Therapeutic Treatment: Restore intravascular volume (85% stop spontaneously) Persistent --> celiotomy (segmental or total colectomy) Ischemic Colitis Due to occlusion of major mesenteric vessel Thrombosis, embolization, iatrogenic ligation) Elderly: - contraceptive pills - medical problems: a) cardiovascular disease b) DM c) Rheumatoid arthritis Splenic flexure – most common site in the colon Ischemic Colitis: Clinical Syndrome Based on: 1. Extent of vascular occlusion Duration of occlusion Efficiency of collateral circulation Extent of secondary bacterial invasion Reversible or Transient Ischemic Colitis: 2. Partial mucosal slough that healed after 2-3 days Stricturing Ischemic Colitis: Arterial occlusion ---> hge’ic infarct of mucosa ---> ulcerates ----> bacterial invasion of bowel ---> fibrosis Ischemic Colitis: Clinical Syndrome Based on: 3. Gangrenous ischemic Colitis: Complete arterial occlusion ---> full thickness infarction ---> gangrene ---> perforation ----> PERITONITIS. Ischemic Colitis: Symptoms: Depends on the stage of the lesion Acute mild to moderate generalized or lower abdominal crampy pain ---> HEMATOCHEZIA Hyperactive bowel sound ---> silent Abdominal tenderness ---> persist --->r/o peritonitis Ischemic Colitis: Diagnosis: Clinical hx & PE FPA ---> adynamic ileus (stops at the involved segment); Pneumoperitoneum Contrast enema (water soluble) - thumb printing in the mucosa Endoscopy (risky) Ischemic Colitis: Treatment: Emergency celiotomy - segmental resection w/ primary anastomosis or colostomy Megacolon: Large colon due to chronic dilatation, elongation and hypertrophy of the colon Due to chronic partial colonic obstruction w/ associated chronic constipation Degree of megacolon is proportional to duration of obstruction Megacolon: 1. Congenital Megacolon (Hirschsprung disease) 2. Congenital absence of ganglion cells in the myenteric plexus (submucosa) of the bowel (aganglionosis) Usually involves the rectosigmoid Must be sent to Patho and confirm the presence of ganglion Acquired megacolon Chaga’s disease (trypanosoma cruzi) Neurologic disorders / psychotic patients Cut higher than 2 cm Fecal impaction: Is the arrest and accumulation of the feces in the rectum or colon (dehydrated feces). Overflow diarrhea w/o relief of the sense of rectal fullness Result to stercoral ulcer (in the plating) --> bleeding and perforation Mx: - tap water enema / manual extraction - hot sitz bath Inflammatory Bowel Diseases: 1. Ulcerative colitis (Mucosal Ulcerative Colitis / Idiopathic Ulcerative Colitis): 2. involve the colonic mucosa – only the colon male > female limited to the colon and rectum Chronic inflammation of GI tract Crohn’s Disease (Chronic Interstitial Enteritis/Regional Ilietis): transmural inflammation anywhere in the GIT – affects entire wall extraintestinal symptoms proceeds those of intestinal symptoms female > male Chronic inflammation of GI tract Inflammatory Bowel Disease: Signs and Symptoms Crohn’s Disease Ulcerative Colitis +++ +++ rectal bleeding + +++ tenesmus 0 +++ +++ + ++ + vomiting +++ 0 weight loss +++ + perianal disease +++ 0 abdominal mass +++ 0 malnutriton +++ + Symptoms diarrhea abdominal pain fever Signs Inflammatory Bowel Diseases: Ulcerative Colitis Crohn’s Colitis Usual Location rectum, left colon anywhere Rectal Bleeding common, continuous uncommon, intermittent Rectal involvement almost always approximate 50% Fistulas rare common Ulcers shaggy, irregular, continuous distribution linear w/ transverse fissures (cobblestone or skip lesion) Bowel stricture rare (suspect carcinoma) common Carcinoma increase incidence increased incidence Toxic dilatation of colon (megacolon) Occurs in both Inflammatory Bowel Diseases: Chronic Ulcerative Colitis: Mild & Mod. acute findings: mucosal edema crypt abscess rectal involvement Severe acute disease: Pseudopolyps w/ marked mucosal inflammation & edema Late changes: Discrete ulcers, pus Inflammatory Bowel Diseases: Crohn’s Disease: Early findings: rectal sparing perianal disease aphthous ulceration Moderate changes: linear ulcers cobblestoning skip lesions Late changes: Contact bleeding Confluent ulcers Strictures & mucosal bridging Inflammatory Bowel Diseases: Inflammatory Bowel Diseases: Morphologic Features of Crohn’s Disease: Suggestive of Crohn’s Disease: 1. 2. 3. 4. 5. Focal inflammation in the mucosa Ileal involvement Linear or fissuring ulcers Rectal sparing Right sided predominance Highly suggestive of Crohn’s disease: 1. 2. Discontinuous segmental involvement Aphthoid ulcers Pathognomonic of Crohn’s disease: 1. 2. 3. Sarcoid granulomas Transmural inflammation w/ lymphoid nodules Fistulas (at sites other than anus) Bowel Involvement in Crohn’s Disease (exam question) 1. 2. 3. 4. Ileocolic Colonic Small bowel only Anorectal 44% 28% 27% 3% Inflammatory Bowel Diseases: Extra-intestinal Nonhepatic Manifestations of Idiopathic Inflammatory Bowel Disease: (hypothetical autoimmune disease) (don’t need to memorize this list) Musculoskeletal: − − − Blood & Vascular System ankylosing spondylitis and sacroiliitis peripheral arthritis pelvic osteomyelitis Skin and Mouth: − − − erythema nodosum pyoderma gangrenosum aphthous stomatitis Eye: − − uveitis (iritis) episcleritis - anemia - thrombocytosis - leucocytosis - hypercoagulable state Kidneys & Genitourinary - nephrolithiasis - obstructive uropathy - fistulas to genitourinary Other: - Pleurocarditis & Bronchopulmonary vaxculitis Medical Therapy for Ulcerative Colitis & Crohn’s Disease 1. 2. Sulfasalazine – lowers the inflammation Metronidazole (as well as 2nd gen cephalosporin) 3. Corticosteroid – lowers antibody 4. Crohn’s ileocolitis & colitis Perineal colitis Not effective in active ulcerative colitis Oral for mild to moderate active ulcerative colitis and Crohn’s disease Parenteral for severe or toxic ulcerative colitis or Crohn’s disease Immunosuppressive agents: Steroid sparing Refractory disease Indications for Surgical Interventions for Ulcerative Colitis: 1. 2. 3. Active disease unresponsive to medical therapy Risks of cancer – based on workup Severe bleeding Surgical treatment for Ulcerative Colitis 1. Proctocolectomy w/ Brooke ileostomy (brings ileum to the skin): 2. Colectomy w/ ileorectal anastomosis: 3. curative w/ one operation not curative; cancer risk persists (5-50%) contraindicated for severe rectal dse, rectal dysplasia and rectal CA Total proctocolectomy w/ ileoanal anastomosis w/ pouch (best therapy): curative w/ continence contraindicated for Crohn’s dse, diarrhea, rectal CA Surgical treatment for Ulcerative Colitis Indications for Surgical Treatment of Crohn’s Dsease 1. Ileocolic Crohn’s Disease: 2. Internal fistula and abscess Intestinal obstruction Perianal fistula Poor response to medical therapy 38% 37% 15% 6% Colonic Crohn’s Disease (when surgery participates): Internal fistula and abscesses Perianal disease Severe dse w/ poor response to medical therapy Toxic megacolon Intestinal obstruction 25% 23% 21% 19% 12% COLO – RECTAL POLYPS Projection from the surface of the intestinal mucosa regardless of it’s histologic nature: Types: 1. 2. 3. 4. Neoplastic Hamartomatous Inflammatory Unclassified COLO – RECTAL POLYPS Neoplastic Polyps: Types Malignant Potential (%) Tubular Incidence (%) 75 Villous 10 40 Tubulovillous 15 22 5 Invasive CA are common in polyps smaller than 1 cm in diameter and incidence increases w/ increase in size COLO – RECTAL POLYPS Neoplastic Polyps: Diagnosis: bleeding per rectum (most common) Villous polyp (large) ---> watery diarrhea and in rare cases can have fluid and electrolyte imbalance do complete examination of the colon colonoscopy biopsy / transrectal ultrasonography COLO – RECTAL POLYPS Neoplastic Polyps: Treatment: Polypectomy for benign ---> follow up (+) CA in situ ----> polypectomy (+) invasive CA (invade the muscularis mucosa) 9% metastasize to LN if pedunculated 20% metastasize to LN if it invades the stalk or neck 15% metastasize to LN if sessile CANCER SURGERY COLO – RECTAL POLYPS Neoplastic Polyps: Treatment: If entire mucosal surface is covered by villous tumor ---> segmental resection, if in rectum can do full thickness proximal protectomy w/ coloanal anastomosis COLO – RECTAL POLYPS Hamartomatous Polyp: 1. Juvenile Polyp: 2. not precancerous excision Swiss cheese appearance from dilated cystic spaces Familial Juvenile Polyposis Coli: thousands polyps in the colon and rectum can degenerate to adenoma ----> malignancy subtotal colectomy or proctocolectomy COLO – RECTAL POLYPS Hamartomatous Polyp: Peutz-jegher Syndrome 3. a. b. 4. Cronkhite – Canada Syndrome: 5. Melanin spot on buccal mucosa, lips, face and digits Polyps of small bowel (always), stomach, colon and rectum (branching of lamina propria like Christmas tree). Can degenerate into malignancy GIT polyposis, alopecia, cutaneous pigmentation, atrophy of fingernails and toe nails Cowden’s Syndrome: Autosomal dominant, hamartomas of all three embryonal cell layers Facial trichilemomas, breast cancer, thyroid dse, GIT polyp COLO – RECTAL POLYPS Infammatory Polyp: Caused by previous attacks of severe colitis resulting in partial loss of mucosa leaving remnants or islands of normal mucosa Occurs after amebic colitis, ischemic colitis and Schistosomal colitis Not premalignant Hyperplastic Polyp: Usually small < 5mm not premalignant > 2cm. have a slight risk of malignant degeneration Saw tooth appearance of the lining epithelial cells COLO – RECTAL POLYPS Familial Adenomatous Polyposis Coli: 1. Inherited non-sex linked autosomal dominant disease w/ hundreds of adenomatous polyps through the entire colon and rectum Gardner’s Syndrome: Familial polyposis, osteomatosis, epidermoid cyst, fibromas of the skin (desmoid tumor) – the most important extra-colonic expression. Tx: - total proctocolectomy w/ ileostomy - colectomy w/ ileorectal anastomosis - examine other members of the family COLO – RECTAL POLYPS Familial Adenomatous Polyposis Coli: 2. Turcot’s Syndrome: Familial polyposis, brains tumors (gliomas or medulloblastomas) Tx: same w/ colorectal involvement Hereditary Nonpolyposis Colon Cancer (HNCC): Lynch’s syndrome Error in mismatch repair (RER pathway) Appear more common in proximal colon Associated w/ extra-colonic malignancies (endometrial, ovarian, pancreas, stomach, small bowel, biliary & Urinary) Carcinoma of Colon Most common CA of the GIT Older age grp; peak incidence 80y/o male ( > rectum) ; female ( > colon) Etiology: 1. 2. 3. Unknown Hereditary Diet --> low fiber diet and high animal fat Distribution --> shifting to the right side Carcinoma of Colon Macroscopic form: 1. 2. 3. Ulcerating type Polypoid or fungating Colloid CA 4. 5. bulky growth w/ gelatinous appearance 10-15% Signet ring cell CA intracellular mucinous Infiltrating CA most common submucosal spread Carcinoma of Colon Microscopic form: adenocarcinoma Gronnell: based on invasive tendency, glandular arrangement, nuclear polarity and frequency of mitosis. Grade I Grade II Grade III - low grade / well differentiated - average grade / mod. differentiated - high grade / poorly differentiated Carcinoma of Colon Mechanism of Spread: Direct spread 2. Transperitoneal spread 3. Implantation 4. Lymphatic 5. Hematogenous Liver & Lungs – most common distant spread 1. Carcinoma of Colon Duke’s Stage: Depth of bowel wall involvement Presence or absence of LN metastasis Stage A: Invasion at least through the muscularis mucosa but not through the muscularis propria 98% ---> 5yr survival Stage B: Invasion through full thickness of bowel wall; (-) LN 78% ----> 5yr survival Carcinoma of Colon Duke’s Stage: Stage C: LN metastasis, regardless of depth Stage C1: - only adjacent LN metastasis Stage C2: - LN involves are nodes at point of ligature of blood vessels 32% 5 yr survival Stage D: Distant metastasis or w/ adjacent organ involvement 0% 5 yr survival TNM Staging of Colonic CA Primary Tumor (T): TX - Primary tumor cannot be assessed T0 - No evidence of primary tumor T1 - Tumor invades submucosa T2 - Tumor invades muscularis proper T3 - Tumor invades through the muscularis proper into the subserosa or into nonperitonealized pericolic or perirectal tissue T4 - Tumor perforates the visceral peritoneum or directly invades the organs or structures TNM Staging of Colonic CA Regional Lymph Node (N): NX – Regional LN cannot be assessed N0 - No regional LN metastasis N1 - Metastasis in 1 to 3 pericolic or perirectal LN N2 - metastasis in 4 or more pericolic or perirectal LN N3 - Metastasis in any LN along the course of a named vascular trunk Distant Metastasis (M): MX – Presence of distant metastasis cannot be assessed M0 - No distant metastasis M1 - w/ distant metastasis TNM Staging of Colonic CA Stage I: T1 –T2 N0 M0 90% 5y/r Survival Stage II: T3 – T4 N0 M0 60 – 80% 5 y/r survival Stage III: Any T Any T N1 N2, N3 M0 M0 20 – 50% 5y/r survival Stage IV; Any T Any N < 5% 5 yr survival M1 Risk Factors for Colorectal CA 1. 2. Aging is the dominant risk factor w/ rising incidence after 50 y/o. Hereditary risk factor: 3. Dietary factors: 4. 5. 80% colorectal are sporadic 20% w/ known family hx. high animal fat (saturated or polyunsaturated fats), but oleic acid (coconut & fish oil does not). Vegetable fiber, Ca, selenium, Vits. A, C, & E are protective Alcohol increase colonic CA Obesity and sedentary lifestyle contributory Smoking increased the incidence Premalignant Diseases of Colon & Rectum Adenoma Familial adenomatous polyposis syndrome Gardner’s syndrome Hamartomas (familial juvenile polyposis coli & Peutz-Jegher polyp Inflammatory bowel disease 1. 2. 3. 4. 5. a. b. 6. 7. Ulcerative colitis Crohn’s disease Schistosomiasis (Billharziasis) – S. mansoni & S. japonicum Utero-sigmoidostomy Genetic Defects for Colorectal CA Mutation may cause: 1. Activation of: 2. K-ras (an oncogene) Inactivation of tumor- suppressor gene: APC DCC (deleted in colorectal carcinoma) p53 Genetic Pathways for Tumor Initiation and Progression 1. LOH pathway: 2. Chromosomal deletion and tumor aneuploidy 80% of colorectal carcinoma RER pathway (replication error): Error in mismatch repair during DNA replication 20% of colorectal carcinoma Carcinoma of Colon Clinical Manifestation: Change in bowel habit Rectal bleeding classic symptoms Weight loss Abdominal pain, bloating and other signs of obstruction Anemia and anorexia Tenesmus, feeling of incomplete evacuation, and rectal bleeding if lesion is in the rectum Screening Modalities For Colonic Tumors 1. Fecal occult blood testing: 2. 3. Rigid proctoscopy / flexible sigmoidoscopy Colonoscopy: 4. 5. Annual FOBT screening for asymptomatic 50 y/o The most accurate and most complete method for examining the colon Air contrast Barium enema: CT colonography (virtual colonoscopy): Colon is insufflated with air and a spiral CT is performed. Useful for imaging the proximal colon in case of obstruction Therapy for Colonic Carcinoma Principle: Objective is to remove the primary tumor w/ its lymphovascular supply Adjacent organs or tissue invaded shd be resected en block w/ the tumor Tumors cannot be removed, a palliative procedure shd be done. Synchronous CA ---> subtotal or total colectomy Metachronous tumor (second primary colon CA) treated similarly Hemorrhage in an unresectable tumor can be controlled w/ angiographic embolization Therapy for Colonic Carcinoma Stage 0: No risk of LN metastasis Pedunculated / sessile polyp -> endoscopic polypectomy If polyp cannot be removed completely segmental resection shd be done Stage I: (T1,N0,M0): Polypectomy --> for uninvolved stalk (pedunculated) Segmental resection: 1. Sessile polyp 2. Pedunculated polyp ( lymphovascular invasion, poorly differentiated or tumor w/in 1mm. of resection margin ---> high risk of local recurence and metastatic spread) Therapy for Colonic Carcinoma Stage II (T3-4,N0,M0): Surgical resection Adjuvant chemotherapy is suggested for: 1. 2. Young patient Moderate to poorly differentiated Stage III (Tany,N1,M0): Surgical resection + adjuvant chemotherapy (5Fluorouracil, levamisole or leucovorin, capecitabine, irinotecan, oxaliplatin, angiogenesis inhibitor and immunotherapy) Therapy for Colonic Carcinoma Stage IV: (Tany, Nany, M1) Palliative resection of primary and isolated liver metastasis Adjuvant chemotherapy Irresectable ---> diverting colostomy THANK YOU Therapy of Rectal Carcinoma Principle the same w/ colonic CA, but more difficult to achieve negative radial margins bec. of anatomic limitations of the pelvis Local recurrence is higher w/ similar stage of colonic CA. Easier to treat rectal tumors w/ radiations due to less structures radiation-sensitive structures in the pelvis Therapy for Rectal Carcinoma 1. 2. Transanal endoscopic microsurgery Radical resection: - removal of the involved segment of the rectum along with its lymphovascular supply w/ a margin of 2 cm distal mural margin. a. b. 3. Total mesorectal excision (TME) APR Pelvic exenteration: --> enbloc resection of the ureters, bladder, prostate, uterus and vagina together w/ APR. w/ permanent colostomy and ileal conduit. Sacrectomy up to level of S2-S3 junction if necessary. Therapy for Rectal Carcinoma Stage 0 (Tis, N0,M0) Local excision w/ 1 cm margin Stage I: (T1-2,N0,M0) Polypectomy --> confined to the head of the polyp Radical resection --> sessile uT1N0 and uT2N0 rectal CA Therapy for Rectal Carcinoma Stage II (T3-4,N0,M0): 2 school of thought 1. Total mesorectal resection only 2. Radical resection w/ chemo-radiation given preoperatively or postoperatively Advantages of preop chemoradiation: Down grade the tumor can increased likelihood of resection and sphincter saving procedure Disadvantages of preop chemoradiation: 1. 2. 3. Over treatment of early stage tumors Impaired wound healing Pelvic fibrosis increases the risk of operative complications Therapy for Rectal Carcinoma Advantages of postoperative radiation: 1. 2. Allows accurate pathologic staging of the resected tumor and LN Avoids wound healing problems associated w/ preop radiation Stage III (Tany,N1,M0): Radical resection followed w/ neodjuvant therapy Stage IV (Tany, Nany, M1) Proximal diverting colostomy for obstruction (lower) / intraluminal stenting (upper) Radical resection to control bleeding, pain and tenesmus Follow-up and Surveillance for Colorectal CA Annual colonoscopy CEA determination CT scan done if CEA is elevated Anal Canal & Perianal Tumors Uncommon; 2% colorectal CA Anal margin – distal to dentate line Anal canal – proximal to dentate line Anal Canal & Perianal Tumors 1. Anal intraepithelial neoplasm (AIN) Bowen’s disease Squamous cell CA in situ of the anus Precursor to an invasive squamous cell CA Associated w/ infection of human papilloma virus, HIV-positive homosexual Tx: resection / ablation High recurrence ---> 3-6 months follow up Anal Canal & Perianal Tumors 2. Epidermoid carcinoma Squamous cell CA, Cloacogenic CA, Transitional CA, Basaloid CA. Slow growing; present as mass or perianal mass Anal margin --> wide local excision Anal canal or invading anal sphincter --> Nigro protocol ( 5-fluorouracil, mitomycin C, 3000cGy external beam radiation). 80% are cured Recurrence ---> APR Anal Canal & Perianal Tumors 3. Verrucous carcinoma 4. Buschke-Lowenstein Tumor, Giant condyloma accuminata. Do not metastasize Wide excision / radical resection Basal cell carcinoma Rarely metastasize Wide excision tx of choice; recurrence --->APR &/or radiation therapy Anal Canal & Perianal Tumors 5. Adenocarcinoma: 6. Usually a downward spread of low rectal CA Could arise from anal glds or developed from chronic fistula; also from apocrine gld (Paget’s dse) Tx: - radical resection w/ or w/o chemoradiation - Paget’s dse = wide excision Melanoma: Poor prognosis; 5yr survival --> 10% due to sytemic metastasis &/or deeply invasive tumors Wide local resection / APR Adjuvant chemotherapy, biochemotherapy, vaccines, radiotherapy Anorectal Abscess 5 potential spaces: 1. 2. 3. 4. 5. Perianal space Ischiorectal space Intersphincteric space Deep posterior anal space Supralevator space Anorectal Abscess Etiology: Infection of anal gland Organism (fecal & cutaneous flora) 1. 2. 3. E. coli Bacteroides fragilis Streptococcus Manifestation: Pain in the anal region Treatment: Drainage / antibiotic Hygiene Hot sitz bath 4. Clostridium sp. 5. Staphylococcus Anorectal Abscess Types : 1. Perianal abscess 2. Ischiorectal abscess – diffuse swelling of ischiorectal fossa Anorectal Abscess 3. Intersphincteric abscess: 4. No apparent sign of swelling or induration in the perianal area CLUE: --> deep seated tenderness when circum-anal pressure is applied above the dentate line. Drainage: thru the anal canal lining or thru internal sphincteric muscle Supralevator abscess: Uncommon Mimmic acute intra-abdominal condition Etiology: extension of a. b. c. Intersphincteric abscess Ischiorectal abscess Intra-abdominal abscess Necrotizing Peri-anal & Perineal Infection: Etiology: 1. 2. Neglected or delayed treatment of primary anorectal infection Extension of UTI particularly the periurethral gland Manifestation: Pain, tenderness and swelling with crepitation of perianal and scrotum or labia Black spot on the site (necrosis) Treatment: Broad spectrum antibiotic Debridement Hyperalimentation / diverting colostomy &/or cystostomy Fistula-In-Ano: Inflammatory tract w/ secondary opening (external) and a primary opening (internal) in the anal canal. Etiology: Complication of perianal abscess Goodsalls Rule: to locate internal opening Classification of Fistula-inano: 1. 2. 3. 4. Inter-sphincteric Trans-sphincteric Supra-sphincteric Extra-sphincteric Fistula-in-ano Manifestation: Previous history of perianal abscess Rule out ulcerative colitis and Crohn’s dse (colonoscopy / barium enema) Treatment: 1. 2. Identify the primary opening (probing/methylene blue/fistulography) Fistulotomy / fistulectomy (healing by secondary intension Fistula-in-ano 1. 2. If fistula is high in relation to anorectal ring do 2 stage procedure: Insert a seton wire or suture to the tract for several wks to create fibrosis Open the fibrous track on the second stage after 6-8 wks Hemorrhoid 1. Are cushions of submucosal tissue in the anal canal composed of connective tissue containing venules, arterioles and smooth muscle fibers. Purposed – aids in anal continence and cushion the anal canal and support the lining during defecation External skin tag Redundant fibrotic skin at the anal verge due to previous thrombosed external hemorrhoid of past operation Hemorrhoid 2. External hemorrhoid Dilated venules of the inferior hemorrhoidal plexus located distal to the pectinate or dentate line Hemorrhoid 3. Internal hemorrhoid: Manifestation: Painless bright red rectal bleeding associated w/ bowel movement Feeling of incomplete evacuation of feces Pain is experienced if w/ complication of anal fissure, stenosis of thrombosis Grade According to Degree of Prolapse: 1st degree: anal cushion slide down beyond the dentate line on straining Mx: - painless rectal bleeding Tx: - bulk forming agents (psyllium seed) - rubber band ligation Hemorrhoid Rubber band ligation: Hemorrhoid 2nd degree: Prolapse through the anus on straining but spontaneously reduced 3rd degree: Requires manual reduction into the anal canal Tx: rubber band ligation / hemorrhoidectomy 4th degree: Prolapse cannot be reduced hemorrhoidectomy Anal Fissure Tear from the dentate line up to the anal verge lined by skin Seen in young and middle age group Majority occurs at the at the posterior midline due to poor muscular support Anal Fissure Etiology: 1. Passage of large hard stool 2. Conditions ( Crohn’s dse, ulcerative colitis, syphilis’ tuberculosis and leukemia) Manifestation: Burning pain during and after bowel movement Bright red blood on toilet paper Diagnosis: Rectal examination / proctosigmoidoscopy Treatment: Conservative: - anal hygiene / bulk forming agents - hot sitz bath - local anesthetic jelly Surgical: - chronic stage (lateral internal sphincterotomy) Anal Fissure Treatment: Conservative: anal hygiene / bulk forming agents hot sitz bath local anesthetic jelly Surgical: chronic stage (lateral internal sphincterotomy)