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Based upon recent American Cancer Society data, colorectal cancer is the third most common cancer in the United States (approximately 150,000 new cases will be diagnosed in 2008), and is the second most common cause of cancer death in men, and the third most common cause of cancer death in women (an estimated 55,000 deaths due to colorectal cancer will occur in 2008, or about 10% of all projected cancer deaths in the US). Colorectal cancer affects men and women equally, and as with most cancers, risk increases with advancing age. Fortunately, both the incidence of colorectal cancer and its death rate have been decreasing since 1985, due to improvements in prevention, screening, earlier diagnosis, and more effective therapies. Unlike many other cancers, most colorectal cancers are thought to arise from benign "precursor" polyps that, if ignored over time, can progress to become cancer. In the hands of an experienced physician, more than 95% of these premalignant polyps (adenomas) can be identified and removed during colonoscopy, effectively preventing the development of cancer in the removed polyps.
Several risk factors for colorectal cancer have been identified. In the general population, age remains a significant risk factor, as more than 90% of all colorectal cancers are diagnosed after the age of 50. There are several known inherited forms of colorectal cancer as well, and patients with these syndromes are at very high risk of developing multiple colorectal cancers, and at a much earlier age than the general population. The two most common hereditary colorectal cancer syndromes are familial adenomatous polyposis (FAP) syndrome and hereditary nonpolyposis colorectal cancer (HNPCC) syndrome. Another feature of these hereditary cancer syndromes is an increased risk of other types of cancers. Patients with inherited cancer syndromes require especially close surveillance, and early surgical intervention. Another group of patients with a significantly increased risk of developing colorectal cancer are those people with underlying chronic inflammatory diseases of the colon and rectum, including Crohn’s colitis and ulcerative colitis. Patients with these inflammatory bowel diseases also require frequent and lifelong colonoscopy in order to detect the development of premalignant or malignant lesions of the colon and rectum in a timely manner. Other risk factors that have been associated with colorectal cancer include obesity, frequent consumption of red meat and highly processed meats, excessive alcohol intake, a sedentary lifestyle, and smoking. Older research suggested that a diet rich in fiber, and fruits and vegetables in particular, could reduce colorectal cancer risk, although more recent research has called this into question (however, there is still strong evidence supporting better overall health in people who generously incorporate fruits and vegetables into their diet).
Colorectal cancer prevention begins with a healthy lifestyle, and continues with adherence to recommended colorectal cancer screening guidelines. A healthy diet, rich in fruits and vegetables, and low in fat (and animal fat from red meat and processed meats, in particular), combined with a healthy, physically active lifestyle, will not only reduce your risk of colorectal cancer and other cancers, but will also improve your overall cardiovascular health as well. Abstaining from smoking, avoiding obesity, and limiting your intake of alcohol offer additional health benefits, and may further reduce your risk of colorectal cancer. Although aspirin and the related nonsteroidal anti-inflammatory drugs (NSAIDs), including ibuprofen, naproxen, celecoxib (Celebrex), rofecoxib (Vioxx), and sulindac (Clinoril) have all been shown to reduce polyp formation in the colon and rectum, recent concerns about potential adverse cardiovascular effects associated with at least some of these drugs has resulted in an ongoing reevaluation of their role in colorectal cancer prevention.
Because colorectal cancer is one of the few cancers that can be effectively prevented with adequate screening, compliance with current public health screening recommendations is absolutely essential. For the general population, focused colorectal screening should begin at 50 years age, and earlier for those patients with multiple first and second degree relatives affected with colorectal cancer (and especially before age 60), or in those patients with inherited colorectal cancer syndromes of underlying inflammatory bowel diseases. Although current public health screening guidelines for colorectal cancer list a variety of screening options, extensive research has shown that colonoscopy provides the most sensitive and accurate means of detecting and treating most colon and rectal polyps. Colonoscopy, therefore, remains the “gold standard” screening test for colorectal cancer.
Current American Cancer Society (ACS) colorectal cancer screening guidelines are listed below. Once again, it must be stressed that colonoscopy remains the most accurate method of detecting colorectal polyps or cancers, and is the only screening technique that also allows for polyps to be removed or biopsied. Currently, Medicare and most health insurance companies will authorize screening colonoscopy for the general population, beginning at age 50.
Beginning at age 50 (average risk men and women), follow at least one of the following recommendations:
1. Yearly stool blood test (FOBT) or fecal immunochemical test (FIT)
2. Flexible sigmoidoscopy every 5 years
3. Yearly stool blood test plus flexible sigmoidoscopy every 5 years
4. Double-contrast barium enema every 5 years
5. Colonoscopy every 5-10 years (newer guidelines suggest colonoscopy every 10 years for patients with average risk for colorectal cancer, and a previously normal colonoscopy)
While a digital rectal exam (DRE) is often done as part of a regular physical exam, it should not be used as a stand-alone test for colorectal cancer.
If anything abnormal is found on any screening tests for colorectal cancer, then a colonoscopy should be performed.
People with certain risk factors should begin screening earlier or have screening more often. For more information, please, talk to your doctor about your own personal risk of colorectal cancer, and when you should begin colorectal screening tests.
The signs and symptoms of colorectal cancer may be very subtle, or may not be apparent at all, particularly during early stages of the disease. Some patients, however, may note blood in their in their stools, or very dark or black colored stool. Changes in bowel habits, and particularly the new onset of difficulty in passing stools, or crampy lower abdominal pain (often improved after having a bowel movement), may be associated with colorectal cancer. However, these same signs and symptoms are also commonly associated with diseases other than cancer.
For the majority of patients diagnosed with colorectal cancer, surgery is the primary treatment. In most cases, the segment of colon or rectum involved by the cancer is removed, along with adjacent lymph nodes. In the vast majority of patients, the colon or rectum can be reconnected at the time of surgery, thus avoiding the need for colostomy. Colostomy, whether temporary or permanent, is still occasionally required for patients who present with very advanced colorectal cancers, or in patients with very low rectal cancers. Occasionally, a temporary ileostomy or colostomy may be created by the surgeon to protect a high-risk anastomosis (the reconnected ends of the colon or/and rectum), but these can often be reversed a few weeks or months later. Historically, patients who presented with colorectal cancer, and were found to have spread of their disease to the liver or other organs already (i.e., metastatic cancer), were often not referred for surgery. However, significant advances in the effectiveness of chemotherapy have offered even patients with metastatic colorectal cancer a reasonable chance at prolonged survival, and many of these patients are now being considered as candidates for surgical removal of their colorectal cancers, either before or after chemotherapy. Additionally, many colorectal cancer patients who have developed metastatic disease in their liver, lungs or other organs can now be effectively treated with various combinations of surgery, tumor ablation techniques (e.g., radiofrequency ablation, or RFA), radiation therapy and chemotherapy (all of these state-of-the-art treatment techniques are available at Newark Beth Israel Medical Center). Another recent innovation in the surgical treatment of colorectal cancer has been the use of minimally invasive techniques to perform exactly the same cancer operation as before, but using advanced surgical techniques that result in smaller incisions, reduced postoperative recovery time, while providing equivalent survival (based upon recent clinical research data). The use of advanced laparoscopic and robotic surgical techniques in the treatment of colorectal cancer, in eligible patients, has translated into a more rapid recovery from surgery for our patients, and without any compromise in cancer-related recurrence or survival when compared to standard surgical approaches to this disease. For patients with rectal cancer, the increased use of chemotherapy and radiation therapy before surgery, for eligible patients has, in combination with improved surgical techniques (e.g., total mesorectal excision, or TME), also significantly decreased the need for permanent colostomy, and has markedly reduced the risk of cancer recurrence in the area of the prior rectal tumor.
In addition to advances in the surgical management of colorectal cancer, newer anti-cancer drugs with increased efficacy have also significantly improved colorectal cancer survivability. These drugs, including oxaliplatin, irinotecan, Avastin (bevacizumab), and Erbitux (cetuximab), have markedly improved survival, compared to previous drugs, even in patients with relatively advanced colorectal cancers. In patients with rectal cancer, chemotherapy (and radiation) is often recommended prior to surgery and, occasionally, following surgery as well. In all other patients with colorectal cancer, chemotherapy following surgery is usually recommended for patients who have lymph node involvement, or/and in patients with primary tumors that have deeply invaded (or perforated or obstructed) the colon or rectum, and with metastatic colorectal cancer.
Considerable progress in the treatment of colorectal cancer has been made over the past 10 years, and new advances are to be anticipated in the near future. There are numerous ongoing clinical research trials available to eligible patients with colorectal cancer as well, and these trials are a source of considerable hope for further improvements in survival and quality of life for patients diagnosed with colorectal cancer.
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