Intestine and Colon Disorders: Diverticular Disease, Colon Polyps, and Colorectal Cancer

outpouching, diverticulosis, infectious, older, diet, NSAIDs

Diverticular Disease

-Diverticula → ____________ of colonic wall

-__________→ presence of diverticula and typically asymptomatic

-Diverticulitis → inflammation and/or __________ diverticular disease

-Risk Factors → _____ age, obesity, smoking, ____ (low fiber, high fat, red meat), physical inactivity, and medication use (ASA, _______, steroids, opiates) 

anywhere, left, sigmoid

Diverticular Disease

-Can occur ____________ in GI tract

-____ colon most common in Western countries (_______ most common) 

-Right colon most common in Asian countries

-Small intestines is very rare 

pressure, motility, weak, vasa recta, contraction, herniation, decreases

Diverticular Disease: Pathophysiology 

-Associated with increased intracolonic _________, abnormal neuromuscular function, and alterations in intestinal _______

-Diverticulosis 

• Tend to form at ____ points in the colonic wall where ____ _____ penetrate the circular muscle layer 

• Exaggerated segmentation ___________ → increases intraluminal pressure → _________ of the mucosa and submucosa through the muscle layer 

• Laplace’s law → wall pressure increases as diameter of a cylindrical structure __________

herniates, injury, perforation, mesentery, peritonitis 

Diverticular Disease: Pathophysiology

-Diverticular Bleeding

• Diverticulum _______ → penetrating vessel draped over dome → exposes vasa recta to ______ → bleeding 

-Diverticulitis 

• Erosion of diverticular wall → inflammation → necrosis → micro/macroscopic __________

• Usually walled off by pericolic fat and ________ → can lead to abscess or obstruction 

• If not walled off then can be free perforation and __________

LLQ, guarding, constipation, obstruction, bladder

Diverticulitis: Symptoms and Complications

-Symptoms

• Abdominal pain (___ most common) → constant, often present for several days. May exhibit _________, rigidity, and rebound tenderness

• N/V and fever possible

• Change in bowel habits → ___________ (MC) vs diarrhea

-Complications

• Abscess, bowel ___________, fistula (with ______ most common), and perforation (of abscess or free)

CT, contrast, thickening, diverticula, colonoscopy, perforation, 6-8

Diverticulitis: Diagnosis

-Labs → CBC

-Imaging → Abdominal __ with oral/IV ________ (preferred imaging)

• Localized bowel wall ___________ (>4mm)

• Increases soft tissue density within pericolonic fat (fat stranding)

• Presence of _________

• Can also find complications if present

-___________ should be avoided during acute diverticulitis d/t risk of _________

-After resolution of symptoms (_-_ weeks) a colonoscopy can be performed if the pt hasn’t had one within the previous year

complicated, fever, age, fluids, outpatient

Diverticulitis: Criteria for Inpatient Treatment

-CT shows ___________ diverticulitis 

OR

-CT shows uncomplicated diverticulitis with pt having one or more of the following:

• Sepsis, microperforation or phlegmon, immunosuppression, high _____ (102.5+), significant leukocytosis, severe abdominal pain or peritonitis, advanced ___, significant comorbidities, not able to take in _____ orally, noncompliant or unable to follow up, and failed __________ treatment 

NPO, Metronidazole, emergency, uncomplicated, drainage, cancer, resection

Diverticulitis: Inpatient Treatment

-IV antibiotics, fluids, pain control, bowel rest (___)

-Uncomplicated → IV antibiotics

• Cover normal GI flora (gram - rods and anaerobes)

• Ertapenem or piperacillin-tazobactam or ampicillin/sulbactam

• Ciprofloxacin plus ____________

-Complicated → treat the complication

• Free perforation = __________ surgery

• Microperforation = treated like ___________ inpatient

• Abscess = percutaneous ________ vs surgery

• Obstruction = affected bowel resection (r/o _____)

• Fistula = affected bowel __________

rest, antibiotics, Amoxicillin/Clavulanate, 2-3, weekly

Diverticulitis: Outpatient Treatment

-Bowel ____ (clear liquid diet)

-_________ (7-10 days) in select patients

• Ciprofloxacin plus Metronidazole or ___________/___________

-Follow up in _-_ days and then _______ until symptoms resolve

lower, spontaneously, 70, painless, stool, colonoscopy

Diverticular Bleeding: Background

-Most common cause of overt _____ GI bleeding, where most bleeding stops _____________

-Risk Factors → age > __, bilateral diverticulosis, and obesity 

-Symptoms → __________ hematochezia or dark/maroon colored ____

-Diagnosis/Treatment

• ___________ (test of choice) → provide endoscopic therapy (submucosal epinephrine injection or tamponade)

• Nuclear scintigraphy with angiography → angiographic therapy (infusion of vasoconstricting meds or embolization)

• Surgical intervention → segmental or subtotal colectomy 

mucosa, IBD, dysplasia, benign, adenomatous, neoplastic

Colon Polyps: Types

-Mass or finger like projection arising from the colonic ______

-Inflammatory Pseudopolyps → seen in ___, can be associated with surrounding __________ in those with IBD

-Harmartomatous Polyps → made of normal tissue but growing in disorganized mass. May increase CRC risk in some cases

-Serrated Polyps → sawtooth appearance, larger in size. _____ (hyperplastic) to increased risk of CRC (sessile serrated and serrated adenoma)

-_____________ polyps → most common __________ polyp in the colon

• Tubular (MC), villous (high risk for cancer), tubulovillous

• All have some form of dysplasia

1-2, 5-10, 3

Screening in Those with Adenomatous Polyps

-Low Risk Adenomas

• _-_ tubular adenomas < 10mm

• Follow up colonoscopy in _-__ years

-High Risk Adenomas

• 3-10 adenomas or tubular adenomas

• One is >6mm, villous adenoma or high grade dysplasia

• Follow up colonoscopy in _ years

50, adenocarcinoma

Colorectal Cancer: Background

-Epidemiology → most common in those > __, incidence slowly rising in those 20-54 

-Pathology → >90% arise from adenomatous polyps, leading to ____________

• Takes 10-15 yrs 

polyps, cancer, familial, IBD, ETOH, processed

Colorectal Cancer: Risk Factors

-Age

-Hx of colorectal _____ (adenomatous or serrated polyps)

-Family history of colorectal _____

-_______ adenomatous polyposis

-Hereditary nonpolyposis colorectal cancer

-___ after 8-10 yrs

-Type 2 DM

-Smoking or chewing tobacco

-Obesity

-Physical inactivity

-Moderate-heavy ____ use

-High consumption of __________ meat

-Red meat consumption

-High fat-low fiber diets

screening, iron deficiency, bowel habits, diarrhea, bleeding, obstruction

Colorectal Cancer: Clinical Presentation

-Asymptomatic → found on routine __________

-Suspicious Symptoms/Signs

• ____ _________ anemia → fatigue, weakness, pale. Found on routine lab work, more common in right sided CRC

• Change in _____ _____ (MC symptoms) → constipation, _______. More common in left sided CRC

• Rectal _________ (second MC symptom) → more common in rectosigmoid CRC

• Bowel obstruction

mucosa, biopsy, apple core

Colorectal Cancer: Diagnosis

-Colonoscopy (preferred)

• Endoluminal mass arising from ______

• Bleeding may be present

• ______ must be done to confirm diagnosis 

-Barium Enema

• _____ ____ lesion

-CT colonography 

CT, liver, rectal, lymph

Staging of Colorectal Cancer

-Chest/Abdominopelvic __ w/ contrast

• Metastases (20% at presentation)

• Most common _____, lungs, peritoneum

-Pelvic MR or Endorectal US (____ cancer)

• Tumors arising about 12 cm or less proximal to the anal verge

• Determines depth of penetration through rectal wall and presence of perirectal ____ nodes

Stage IV

What stage of colon cancer is this?

-Metastasis to distant organs

rectal

For each stage of colon cancer, ______ cancer has a worse prognosis 

screening, monitor, CRC, elevate

CEA (carcinoembryonic antigen)

-Tumor marker → normal is < 5 mcg/L

-Not used for CRC ___________, low specificity and sensitivity for early disease

-Used to _______ patients with ___ → pretreatment levels compared to treatment and post-treatment levels

-Levels _________ as CRC progresses

surgery, preoperative, III, IV, metastasis

Colorectal Cancer: Treatment

-________ → treatment of choice in those with resectable lesions

• Rectal cancer → recommended ______________ chemoradiation with 5-fluorouracil in node positive d/t increased risk of recurrence

-Chemotherapy

• Stage I = none recommended

• Stage II = may be recommended in pts at high risk for recurrence

• Stage ___ and __ = recommended

-Metastasis → isolated hepatic or pulmonary __________ may be resectable

colonoscopy, 1, 3-5

Colorectal Cancer: Follow Up After Surgical Resection for Cure

-Evaluate every 3-6 mo x 2 yrs then every 6 mo for a total of 5 yrs 

-____________ at _ yr s/p resection

• If no adenomatous polyps can go to every _-_ years 

CRC, activity, fiber, NSAID

Colorectal Cancer: Complications and Protective Factors

-Complications

• LBO → MC cause is ___

• Iron deficiency anemia

• Endocarditis → Streptococcus bovis or clostridium septicium

-Protective Factors

• Regular physical _______

• Diet high in ____ and fruits/vegetables

• Possibly ASA or _____ use

inherited, APC, dominant, adenomatous, 15, cancer, colectomy

Familial Adenomatous Polyposis: FAP

-__________ condition → 90% have a mutation of the ___ gene, inherited in an autosomal _________ fashion

-Early development of hundreds to thousands of colonic _____________ polyps

• Mean age of development is __y/o and _____ at 40y/o

• CRC inevitable without proctocolectomy

-Recommended complete proctocolectomy or _______ with ileoanal anastomosis before 20 y/o

dominant, MLH1, MSH2, CRC, colonoscopy, gastric, ovarian, Bethesda Criteria

Lynch Syndrome

-Autosomal __________ inherited condition → 90% have a mutation in the ____ and ____ gene 

-Significant increased risk of ___ as well as other cancers of the abdomen/pelvis 

-Pts only develop a few adenomas, rapid progression to cancer over 1-2 yrs 

-Those with positive genetic testing need ___________ every 1-2 yrs 

• Begin at 25 y/o or 5 yrs before the youngest affected FDR was dx 

• Colectomy w/ileorectal anastomosis if cancer was found

-Screen for ______ cancer every 2-3 years, begin at age 30-35 

-Screen women for endometrial/______ cancer 

• Begin at age 30-35

• Prophylactic hysterectomy/oophorectomy at age 40 

-__________ ________: if one of these criteria are met, the patient should undergo genetic testing 

45, 75, 10, yearly, 3, yearly

Screening for Colorectal Cancer (Average Risk)

-Routine screening recommended for everyone starting at age __ and continuing to __

-Colonoscopy every __ yrs (preferred)

-Other Screening Options

• Fecal Immunochemical Test = ______

• FIT-DNA test = every _ years

• Guiac Fecal Occult Blood Test = ______

10, 40

Screening for Colorectal Cancer (High Risk): Family History in FDR

-Start screening __ yrs before the FDRs dx or by age __, whichever is earlier

45, 30-40, 25, 10-12, 8-10

Screening for Colorectal Cancer (High Risk)

-African American patient → colonoscopy starting at age __

-Prior abdominal/pelvic radiation → colonoscopy between __-__ y/o then every 5-10 yrs 

-Fhx of Lynch Syndrome → colonoscopy starting at age __

-FAP → flexible sigmoidoscopy starting at __-__ y/o yearly, recommend colonoscopy 

-Hx of IBD → colonoscopy _-__ years afte rsx onset then every 1-2 yrs