Note: Separate PDQ summaries on Colorectal Cancer Screening; Colon Cancer Treatment; and Rectal Cancer Treatment are also available.
Factors Associated With Increased Risk of Colorectal Cancer
Excessive alcohol use
Based on solid evidence from observational studies, excessive alcohol use is associated with an increased risk of colorectal cancer (CRC).[1,2,3]
Magnitude of Effect: A pooled analysis of eight cohort studies estimated an adjusted relative risk (RR) of 1.41 (95% confidence...
Standard treatment options for stage II coloncancer include the following:
Wide surgical resection and anastomosis.
Evidence (laparoscopic techniques):
The role of laparoscopic techniques [1,2,3,4] in the treatment of colon cancer was examined in a multicenter, prospective, randomized trial (NCCTG-934653, now closed) comparing laparoscopic-assisted colectomy (LAC) to open colectomy.
Three-year recurrence rates and 3-year overall survival (OS) rates were similar in the two groups. (Refer to the Primary Surgical Therapy section in the Treatment Option Overview section of this summary for more information.)
The quality-of-life component of this trial has been published and minimal short-term quality-of-life benefits with LAC were reported.[Level of evidence: 1iiC]
The potential value of adjuvant chemotherapy for patients with stage II colon cancer remains controversial. Although subgroups of patients with stage II colon cancer may be at higher-than-average risk for recurrence (including those with anatomic features such as tumor adherence to adjacent structures, perforation, complete obstruction),[5,6,7] evidence is inconsistent that adjuvant 5-fluorouracil (5-FU)–based chemotherapy is associated with an improved OS compared with surgery alone.
Features in patients with stage II colon cancer that are associated with an increased risk of recurrence include the following:
Inadequate lymph node sampling.
Involvement of the visceral peritoneum.
A poorly differentiated histology.
The decision to use adjuvant chemotherapy for patients with stage II colon cancer is complicated and requires thoughtful consideration by both patients and their physicians. Adjuvant therapy is not indicated for most patients unless they are entered into a clinical trial.
Evidence (adjuvant chemotherapy):
The GRECCR-03 and NCRI-QUASAR1 trials evaluated the use of systemic or regional chemotherapy or biologic therapy. Following surgery, patients should be considered for entry into a carefully controlled clinical trial.
Investigators from the National Surgical Adjuvant Breast and Bowel Project (NSABP) have indicated that the reduction in risk of recurrence by adjuvant therapy in patients with stage II disease is of similar magnitude to the benefit seen in patients with stage III disease treated with adjuvant therapy, though an OS advantage has not been established.
A meta-analysis of 1,000 stage II patients whose experience was amalgamated from a series of trials indicates a 2% advantage in disease-free survival at 5 years when adjuvant therapy–treated patients treated with 5-FU-leucovorin are compared with untreated controls.[Level of evidence: 1iiDii];
The Cancer Care Ontario Practice Guideline Initiative Gastrointestinal Cancer Disease Site Group undertook a meta-analysis of the English language–published literature consisting of randomized trials in which adjuvant chemotherapy was compared with observation for patients with stage II colon cancer.
The mortality risk ratio was 0.87 (95% confidence interval, 0.75–1.01; P = .07).