This document provides a brief review of colorectal cancer including epidemiology, risk factors, clinical presentation, screening, diagnosis, and treatment options. It notes that globally, colorectal cancer is the third most commonly diagnosed cancer in males and second in females. Screening is recommended for average risk individuals beginning at age 50. Treatment typically involves surgical resection as the only curative option, and may be combined with chemotherapy or radiation therapy depending on the stage of cancer.
3. Epidemiology
Globally is third most commonly diagnosed cancer in males
and second in females. Rates higher in males
In United States incidence and mortality steadily decreasing.
Responsible for approximately 8% of all cancer deaths
4. Risk Factors
Will Influence Screening
Hereditary CRC syndrome (Familial adenomatous polyposis, Lynch syndrome,
MUTYH-associated polyposis), personal or family history of sporadic CRC or
adenomatous polyps, abdominal radiation, inflammatory bowel disease
(Crohn's and Ulcerative colitis)
May Influence Screening
Race, gender, acromegaly, and renal transplant
Do not alter screening
Obesity, DM, red and processed consumption, tobacco, alcohol,
cholecystectomy, others.
5. Clinical Presentation
Suspicious symptoms and/or signs
70-90% diagnosed after onset of symptoms
Asymptomatic patient discovered via routine screening
Emergency admission due to acute intestinal obstruction,
peritonitis, or gastrointestinal bleed
6. Suspicious Symptoms
Hematochezia, melena, abdominal pain, unexplained iron
deficiency anemia, change in bowel habits
Less common includes abdominal distension, Nausea, vomiting
(Possible symptoms due to obstruction)
Metastatic disease
Uncommon: Perforation, fistula, fever of unknown origin,
abscesses (intra-abdominal, retroperitoneal, abdominal wall or
intrahepatic)
7. Screening
Average-risk patient screened for CRC at age 50
Screen until life expectancy less than 10 years (75-85 years old)
One timed screening colonoscopy at 83 or sigmoidoscopy at
84 for those never screened
Potential strategies
Colonoscopy every 10 years
Computed tomographic colonoscopy every five years
Flexible sigmoidoscopy every five years
Fecal occult blood test (FOBT) with immunochemical testing
(iFOBT) annually on single sample
FOBT with guaiac reagent annually on three samples
Multitargetstool DNA testing every three years on one sample
8. Screening
Sufficiently-Increased Risk screened at earlier age (40-45)
Personal History of CRC or adenomatous polyp
Genetic syndrome predisposing to CRC (HNPCC or FAP)
One first-degree relative with CRC or advanced adenoma at age
<60 years old
Two or more first-degree relatives with CRC or advanced
adenoma at any age
IBD leading to pancolitis
Personal history of abdominal radiation therapy
9. Diagnosis
Colonoscopy: most accurate and versatile
Flexible sigmoidoscopy
Barium Enema: diagnostic yield less than that of colonoscopy
CT Colonography
PILLCAM 2
Tumor Markers: (i.e. Carcioembryonic Antigen) Low diagnostic
ability
10. Treatment
Surgical resection:
Only curative modality. Goal is complete oncologic resection
Open versus Laparoscopic-assisted colectomy
Laparoscopic has comparable oncologic outcomes, perioperative
morbidity, and mortality and faster recovery.
Surgical specimen should have at least 12 lymph nodes
En bloc multivisceral resection: For locally advanced (T4) tumors
that involve contiguous organs or structures
12. Treatment
Radiation Therapy
Adjuvant radiation therapy considered for patients with a T4
disease and penetration to a fixed structure.
Palliative for Advanced Disease:
For symptomatic patients with un-resectable metastatic disease
Surgery is meant to manage complications
Includes Resection with primary anastomosis, diverting end
colostomy w/ mucous fistula, and bypass procedure
13. References
Doubeni, Chyke, MD, FRCS, MPH. "Screening for Colorectal Cancer:
Strategies in Patients at Average Risk." Screening for Colorectal Cancer:
Strategies in Patients at Average Risk. Ed. J. Thomas Lamont, Joann G.
Elmore, and H. Nancy Sokol. UpToDate, 8 Apr. 2016. Web. 11 July 2016.
Macrae, Finlay A., MD. "Colorectal Cancer: Epidemiology, Risk Factors, and
Protective Factors." Colorectal Cancer: Epidemiology, Risk Factors, and
Protective Factors. Ed. Richard M. Goldberg, Timothy O. Lipman, and Diane
MF Savarese. UpToDate, 15 Apr. 2016. Web. 11 July 2016.
Macrae, Finlay A., MD, and Johana Bendell, MD. "Clinical Presentation,
Diagnosis, and Staging of Colorectal Cancer." Clinical Presentation,
Diagnosis, and Staging of Colorectal Cancer. Ed. Kenneth K. Tanabe,
Diane MF Savarese, and Shilpa Grover. UpToDate, 11 Apr. 2016. Web. 11
July 2016.
Rodriguez-Bigas, Miguel A., MD. "Surgical Resection of Primary Colon
Cancer." Surgical Resection of Primary Colon Cancer. Ed. Martin Weiser
and Wenliang Chen. UpToDate, 16 June 2016. Web. 11 July 2016.