• Colorectal cancer second leading cause of cancer deaths (after lung)
• Adenocarcinoma accounts for 95% of malignant colorectal tumors
• Genetic predisposition in familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer (HNPCC)
• Conditions predisposing to colorectal cancer
• Possible dietary influences
• Carcinogenesis multi-step process involving dysfunction of tumor suppressor genes, including APC, DCC, P53
• Distribution of colorectal cancer
• Spreads through direct extension, hematogenously, lymph nodes, transperitoneal, intraluminal
• Synchronous lesions occur in 3-5%
• 156,000 cases diagnosed per year
• 65,000 colorectal cancer deaths per year
• Incidence increases with age
• Colon cancer is more common in women than men
• Rectal cancer is more common in men than women
• Multiple synchronous colonic cancers found in 5% of patients
• 5% lifetime risk
• 6-8% occurs before age 40 years
• Symptoms depend on anatomic location and extent of lesion
• Right colon lesions may become large before symptoms develop
• Left colon lesions often cause crampy abdominal pain
• Large bowel obstruction ~ 10% cases
• Fatigue, weakness, vague abdominal pain, abdominal mass (< 10%), anemia
• Constipation alternating with increased frequency of defecation
• Dark or blood tinged stool
• Change in stool caliber
• Rectal cancers
• Physical exam findings may include abdominal mass, lymphadenopathy, rectal mass
• Patients may have microcytic, hypochromic anemia
• Positive occult blood on guiac stool test
• Carcinoembryonic antigen (CEA) elevation (nonspecific, more useful for surveillance following resection), prompts additional imaging (CT scan)
• Elevation of biochemical markers (nonspecific): CA 19-9, CA 72-4, plasma prolactin
• Contrast enema-filling defect, "apple core lesion"; constricted area or intraluminal mass
• Total colonoscopy: Should be performed to evaluate lesion and presence of synchronous lesions
• Complete history (including family) and physical exam
• Total colonoscopy with biopsy
• Obtain plain abdominal x-ray and water-soluble contrast enema in patients with bowel obstruction
• Once diagnosis is made, staging studies should be performed
• Endorectal US: Helpful for determining depth of invasion in rectal lesions
Log In to View More
If you don't have a subscription, please view our individual subscription options below to find out how you can gain access to this content.
Want remote access to your institution's subscription?
Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.
If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.
AccessSurgery Full Site: One-Year Subscription
Connect to the full suite of AccessSurgery content and resources including more than 160 instructional videos, 16,000+ high-quality images, interactive board review, 20+ textbooks, and more.
Pay Per View: Timed Access to all of AccessSurgery
24 Hour Subscription $34.95
48 Hour Subscription $54.95
Pop-up div Successfully Displayed
This div only appears when the trigger link is hovered over.
Otherwise it is hidden from view.