Colorectal Cancer in Georgia, 1999-2002
Acknowledgments
Georgia Department of Human Resources.............................................................B. J. Walker, Commissioner Division of Public Health.........................................................................Stuart Brown, M.D., Acting Director Epidemiology Branch............................................. .............................Susan Lance, D.V.M, M.P.H., Director Chronic Disease, Injury, and Environmental Epidemiology Section............ A. Rana Bayakly, M.P.H., Acting Chief Georgia Comprehensive Cancer Registry....................................A. Rana Bayakly, M.P.H., Program Director Chrissy McNamara, M.S.P.H., Epidemiologist Simple Singh, M.D., M.P.H., Epidemiologist Chronic Disease Prevention and Health Promotion Branch...........................Kimberly Redding, MD, MPH, Director Cancer Control Section........................................................Karen Boone, RN, MN, MPH, Nurse Consultant
We would like to thank all of the hospitals in Georgia that contributed data to the Georgia Comprehensive Cancer Registry. Without their hard work, this report would not have been possible.
Suggested Citation: Singh S, Bayakly AR., McNamara C., Redding K. Colorectal Cancer in Georgia, 1999-2002. Georgia Department of Human Resources, Division of Public Health, Chronic Disease, Injury, and Environmental Epidemiology Section, October, 2005. Publication number DPH05/085W.
What is Colorectal Cancer?
Colorectal cancer is a collective term for cancers of the colon and rectum. Since cancers of the colon and rectum share many features, they are often referred to as colorectal cancer. The colon and rectum are parts of the digestive system. They form a long, muscular tube called the large intestine. The colon is the first 4 to 5 feet of the large intestine and the rectum is the last 4 to 5 inches. After food is chewed and swallowed, it travels through the esophagus to the stomach. In the stomach, it is partly digested and then transferred to the small intestine. The small intestine continues digesting the food and absorbs most of the nutrients. The small intestine connects to the large intestine. The colon absorbs water and electrolytes from the food and serves as a storage place for waste. The waste moves from the colon into the rectum. From there, the waste passes out of the body through the opening called the anus during a bowel movement. Colorectal cancers develop slowly over a period of several years. Most of these cancers begin as a polyp--a growth of tissue protruding into the center of the colon or rectum. Polyps are also known as adenomas. Removing the polyp early may prevent it from becoming cancer. Over 95 percent of colon and rectal cancers are adenocarcinomas, cancers arising from the cells that line the inside of the colon and rectum. Colorectal cancer occurs in both men and women and most commonly occurs in people over 50 years of age. Colorectal cancer is the third most commonly diagnosed cancer in Georgia men and women. It is also the third most common cause of cancer death among Georgia men and women. Based on data from Georgia Comprehensive Cancer Registry it is estimated that in 2005, over 4,202 new cases of colorectal cancer will be diagnosed, and about 1,580 Georgians will die from this disease.
How is Colorectal Cancer Detected?
Treatment is more likely to be successful if colorectal cancers are detected early. The American Cancer Society recommends routine colorectal cancer screening beginning at age 50. Several screening tests are available. These include, fecal occult blood tests, digital rectal examination, flexible sigmoidoscopy, colonoscopy, and double contrast barium enema. The American Cancer Society's recommendations for the early detection of colorectal cancer are as follows: Beginning at age 50, both men and women should follow one of the 5 screening options below: 1. A fecal occult blood test (FOBT) * every year 2. Flexible sigmoidoscopy every 5 years 3. A fecal occult blood test every year plus flexible sigmoidoscopy every 5 years* (Of these first 3 options, the combination of FOBT every year and flexible sigmoidoscopy every 5 years is preferable.) 4. Double-contrast barium enema every 5 years 5. Colonoscopy every 10 years *For FOBT, the take-home multiple sample method should be used.
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Who Develops Colorectal Cancer?
ColorectTahl eCoavnecrearllraagtee-saidnjuGsteeodrcgoialo:rectal cancer incidence rate in Georgia is 51 per 100,000. Males are 41% more likely to be diagnosed with colorectal cancer than females (age-adjusted rate 62/100,000 vs. 44/100,000).
The overall age-adjusted colorectal cancer mortality rate is 19 per 100,000. Males are 44% more likely to die of colorectal cancer than females (age-adjusted rate 23/100,000 vs. 16/100,000).
Colorectal Cancer Incidence and Mortality Rates* by Race and Sex, Georgia (Incidence:1999-2002; Mortality:1998-2002) and US (1998-2002)
Rate per 100,000 Rate per 100,000
GA Incidence 1999-2002 US Incidence 1998-2002
100
90
80 71 70 70 60 50 40
66 60
53 54
47 42
30
20
10
0 Black Males
White Males
Black White Females Females
100
GA Mortality 1998-2002 US Mortality 1998-2002
90
80
70
60
50
40 32 34 30 20
21 24
24 24
14 17
10
0 Black Males
White Males
Black White Females Females
*Rates are age-adjusted to 2000 US standard population.
Each year from 1999-2002, over 3,500 colorectal cancers were reported to the Georgia Comprehensive Cancer Registry. Black men and women were more likely to be diagnosed with the disease than were white men and women.
Each year from 1998-2002 over 1,250 Georgians died from colorectal cancer. Mortality rates were higher for black men and women than for white men and women.
What are the Causes and Risk Factors for Colorectal Cancer?
While we do not know the exact cause of most colorectal cancers, there are certain known risk factors. A risk factor is anything that indicates a person has a higher than normal chance of getting a disease such as cancer. Different cancers have different risk factors. Some risk factors, such as diet, can be controlled. Others, such as a person's age or family history, can't be controlled. Researchers have identified several risk factors that increase a person's chance of getting colorectal cancer. But having a risk factor, or even several, doesn't mean that a person will get the disease.
While everyone is at risk for colorectal cancer, the following factors can increase one's chances of getting the disease.
Risk Factors That Can Be Controlled High fat diet: A diet made up mostly of foods that are high in fat, especially from animal sources, can increase the risk of colorectal cancer. The American Cancer Society recommends choosing most of your foods from plant sources and limiting the amount of high-fat foods you eat. Physical inactivity: People who are not active have a higher risk of colorectal cancer. Obesity: Being obese increases a person's colorectal cancer risk. Having extra fat in the waist area increases this risk more than having fat in the thighs or hips. Smoking: Most people know that smoking causes lung cancer, but recent studies show that smokers are 30% to 40% more likely than nonsmokers to die of colorectal cancer. Alcohol consumption: Heavy use of alcohol has been linked to colorectal cancer.
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Risk Factors That You Cannot Change Age: The chances of getting colorectal cancer increase with age. More than 90% of people diagnosed with colorectal cancer are older than 50. Family history: Colorectal cancer risk is higher in men and women who have a close relative who has had the disease. The risk increases even further if the relative is affected before the age of 60, or if more than one relative is affected (at any age). About 5% of patients with colorectal cancer have an inherited genetic abnormality that causes the cancer. People with a family history of colorectal cancer should talk with their doctor about when to begin and how often to have screening tests. Ethnic Background: Jews of Eastern European decent (Ashkenazi Jews) have a higher rate of colon cancer. In one study about 10% of colorectal cancers in Ashkenazi Jews were associated with a genetic mutation. Personal history of colorectal cancer: An individual with colorectal cancer, even though it has been completely removed, is more likely to develop new cancers in the other areas of the colon and rectum. The chances of this happening are greater if the first colorectal cancer was diagnosed at the age of 60 or less. Personal history of polyps: Some types of polyps (inflammatory polyps) do not increase the risk of colorectal cancer. Other types, such as adenomatous polyps and hyperplastic polyps do increase the risk of colorectal cancer. This is especially true if the polyps are large or if there are many of them. Personal history of bowel disease: Inflammatory bowel disease (ulcerative colitis or Crohn's disease) increases the risk of colon cancer. People with inflammatory bowel disease should talk with their doctor about when to begin and how often to have the screening tests. Diabetes: People with diabetes have a 30%-40% increased chance of developing colon cancer. They also tend to have a higher death rate after diagnosis.
What are the Symptoms for Colorectal Cancer?
Cancer that starts in the different sections of the colon and rectum may cause different symptoms. Symptoms of colorectal cancer can mimic other conditions like hemorrhoids, infections and inflammatory bowel disease. It is also possible to have colon cancer and not have any symptoms. If you have any of the following symptoms, it is important to talk to your doctor since finding colorectal cancer early makes successful treatment more likely:
Change in bowel habits: Diarrhea, constipation, or narrowing of stools that last for more than a few days. A feeling that you need to have a bowel movement that is not relieved by doing so Rectal bleeding or blood in stool Cramping or steady abdominal pain Weakness and fatigue
What is Your Risk of Being Diagnosed?
Top Five Cancer Types and Cancer-Related Deaths in Georgia
Male Prostate
Cases Female
Breast
Male Lung & Bronchus
Lung & Bronchus
Lung & Bronchus
Prostate
Colorectal
Colorectal
Colorectal
Bladder
Uterus
Pancreas
Melanoma
Ovary
Leukemia
Deaths Female
Lung & Bronchus
Breast
Colorectal
Pancreas
Ovary
Colorectal cancer is the third most common cancer diagnosed and the third leading cause of cancer deaths among men and women in Georgia. One in 17 Americans will develop colorectal cancer in their lifetime.
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At What Age is Colorectal Cancer Most Often Diagnosed?
Georgia Colorectal Cancer Incidence (1999-2002) and Mortality (1998-2002) Rates, by Age Group and Sex
Females
Males
Rate per 100,000 Rate per 100,000
Incidence Mortality 500
400
300 200 100
0
22 7
63 17
12 5 39
226 82
299 16 5
0-39 40-49 50-59 60-69 70-79 80+
Age Group
Incidence Mortality
500 430
400 317
300
209 189
200
124
100
85
62
26 7
23
0
0-39 40-49 50-59 60-69 70-79 80+
Age Group
Colorectal cancer incidence and mortality rates are higher in older individuals. This cancer rarely occurs among individuals less than 40 years of age. In Georgia, men and women over the age of 80 have the highest incidence rate of colorectal cancer.
Mortality rates also increase with age; the highest rates are seen in men and women 80 years of age and older. Before the age of 40, colorectal cancer deaths are rare. Less than 30 deaths occurred every year in males and females under 40 years of age from 1998 through 2002.
What is the Treatment for Colorectal Cancer?
Each type of treatment has benefits and side effects. Age, overall health, and the stage of the cancer are all factors that need to be considered. Staging is a standardized way to summarize information about how far a cancer has spread from its point of origin. In situ colorectal cancers are confined to the innermost lining of the colon and rectum. Localized colorectal cancers have invaded the middle layers of the colon or rectum, but have not spread to the outermost layer. Regional stage colorectal cancers have spread beyond the colon and rectum to the adjacent tissues, organs, or regional lymph nodes. Distant stage colorectal cancers have spread to sites such as the liver, lungs, or lymph nodes far from the colon and rectum.
There are three main types of treatment for colorectal cancer: surgery, radiation therapy, and chemotherapy. Depending on the stage of cancer, multiple treatment modalities may be used at the same time or one after another.
Surgery: This is the most common treatment. Usually, the cancer and a length of colon or rectum on either side of the cancer including some lymph nodes are removed. A small malignant polyp can be removed from the colon or upper rectum with a colonoscope thus avoiding abdominal surgery.
Chemotherapy: Systemic chemotherapy is given using anti-cancer drugs that are injected into a vein or taken by mouth. These drugs reach all areas of the body through the bloodstream, making it potentially useful to cancers that have metastasized to other parts of the body.
Radiation Therapy: This treatment uses x-rays or other type of radiation to kill cancer cells. There are two types of radiation therapies: External radiation comes from a machine and is directed to the cancer. Internal radioactive material/implants are put directly into or near the cancer. Research has shown that radiation in combination with surgery will often decrease the risk of recurrence of rectal cancer.
Adjuvant and Neoadjuvant Therapy: These terms refer to the timing of chemotherapy and radiation therapy. Neoadjuvant therapy is given prior to surgery to shrink the tumor so that it can be removed more completely. Adjuvant therapy is given after surgery to remove any residual cancer.
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Who Survives Colorectal Cancer?
Percent of US Men and Women Surviving Five Years after Diagnosis of Colorectal Cancer, by Stage of Disease and Race, 1995-2001
Survival Rate
100
90
80
70
65
60
55
50
40
30
20
10
0 All stages
91 84
White Black
69 61
Localized
Regional
Stage at Diagnosis
10 8 Distant
% of Tumors found at this stage*
US White US Black GA White GA Black
*Unstaged tumors are not shown. US data is for 1995-2001, GA data is for 1999-2002
Localized 39% 35% 36% 30%
Regional 38% 35% 40% 40%
Distant 19% 24% 16% 22%
Early detection is important because survival for early stage colorectal cancer is much greater than that for later stage disease. Five-year survival for tumors found in the localized stage, when the cancer is still contained within the colon, is 91 percent among US whites and 84 percent among US blacks. In Georgia, about 36 percent of white men and women and about 30 percent of black men and women are diagnosed at a localized stage. If the cancer spreads to organs away from the colon or rectum (distant stage), five-year survival rate drops to about 10 percent for US white men and women and 8 percent for US black men and women.
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How does Colorectal Cancer Vary by Region?
Urban Rural
Rate per 100,000 Rate per 100,000
Georgia Colorectal Cancer Incidence and Mortality Rates* by Geography
Females
Incidence 1999-2002 Mortality 1998-2002
80
70
60 55
50
50
42 42
40
30
24 23
20
14 15
10
0
Urban Rural Urban Rural
Black Black White White
Males
Incidence 1999-2002 Mortality 1998-2002
80 74
70
66
63
58
60
50
40
33
31
30
20
23
20
10
0
Urban Rural Urban Rural Black Black White White
*Rates are age-adjusted to the 2000 US standard population
Incidence (1999-2002) rates for rural white males were significantly higher than the urban white males. Incidence rates for urban black males and females were higher than the rural black males and females, but the results were not statistically significant.
Mortality (1998-2002) rates for urban black males and females were higher than the rural black males and females, but the results were not statistically significant.
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How Does Georgia Compare with the United States?
Male Colorectal Cancer Mortality Rate*, by Race, Georgia vs. US, 1980-2002
Rate per 100,000
US White
US Black
GA White
GA Black
40
Males
Males
Males
Males
35
30
25
20
15
10
5
0
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002
*Rates are age-adjusted to the 2000 US standard population
Overall, from 1980 to 2002, the colorectal cancer mortality rates among Georgia males were lower than US males.
From 1980 to 1999, the mortality rates among white males decreased by 0.8 percent. Since 1999 the rates have been rising again. The mortality rate among black men has been fluctuating. From 1980 to 1999, the rates increased by 3.2 percent per year and have been decreasing since 1999.
Female Colorectal Cancer Mortality Rate*, by Race, Georgia vs. US, 1980-2002
Rate per 100,000
40
US Whit e
US Black
GA White
GA Black
35
Females
Females
Females
Females
30 25
20 15 10
5 0
1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002
*Rates are age-adjusted to the 2000 US standard population
Overall, from 1980 to 2002, the colorectal cancer mortality rates among Georgia females were lower than US females.
The mortality rate for white women in Georgia has been declining at an average annual decrease of 1.4 percent. The mortality rates among black women have been rising at an average annual increase of 1.7 percent.
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Where Can I Find Out More about Colorectal Cancer?
You can learn more about colorectal cancer from the following organizations:
American Cancer Society Telephone: 1-800-ACS-2345 Internet Address: http://www.cancer.org
Colon Cancer Alliance Telephone: 212-627-7451 Internet Address: http://www.ccalliance.org
National Cancer Institute, Cancer Information Service Telephone: 1-800-4-CANCER Internet Address: http://www.nci.nih.gov
National Colorectal Cancer Research Alliance Telephone: 818-760-7722 Internet Address: http://www.eifoundation.org/home/
Cancer Research and Prevention Foundation (Colossal Colon) Telephone: 1-800-227-2732 Internet Address: http://www.preventcancer.org
Cancer Control Planet Internet Address: http://cancercontrolplanet.cancer.gov/
Technical Notes
Definitions: Age-adjusted rate: A rate calculated in a manner that allows for the comparison of rates derived from populations with different age structures. Cancer incidence rate: The number of new cancer cases occurring in a population during a specified period of time. Often expressed per 100,000 population. Cancer mortality rate: The number of cancer deaths occurring in a population during a specified period of time. Often expressed per 100,000 population.
Data Sources: The number of deaths and mortality rates for the state of Georgia were obtained from the Georgia Department of Human Resources, Division of Public Health, Vital Records Branch. The number of deaths and mortality rates for the United States were obtained from the National Center for Health Statistics, Centers for Disease Control and Prevention (CDC). Mortality data were coded using ICD-9 codes (1980-1998) and ICD-10 codes (1999-2002). The ICD-9 codes for colorectal cancer are 153.0154.1, 159.0, while the ICD-10 codes for colorectal cancer are C180:C209, C260.
The number of new cases and incidence rates for the state of Georgia were obtained from the Georgia Department of Human Resources, Division of Public Health, Georgia Comprehensive Cancer Registry. The number of new cases and incidence rates for the United States were obtained from the North American Association of Central Cancer Registries (NAACCR). Incidence data were coded using ICD-O3 codes. The ICD-O3 codes used for colorectal cancer are C180:C209, C260.
Cancer stage and survival data for the United States were obtained from the Surveillance, Epidemiology, and End Results (SEER) program, National Cancer Institute.
Population projections for 2005 were obtained from the Office of Planning and Budget for the state of Georgia. Population estimates for 1980-2002 and the 2000 US standard population were obtained from the US Bureau of the Census.
Methods: Mortality rates were calculated per 100,000 population and age-adjusted by the direct method to the 2000 US standard population. Except where calculated to show trends, the mortality rates are five-year average annual rates for the period 1998 through 2002. Incidence rates were calculated per 100,000 population and age-adjusted by the direct method to the 2000 US standard population. Rates were calculated for 1999-2002, as these are the years in which Cancer Registry data are greater than 95% complete.
The estimated number of cases for 2005 was calculated by multiplying age-specific incidence rates for 1999-2002 by agespecific population projections for 2005. The estimated number of deaths for 2005 was calculated by multiplying agespecific mortality rates for 1998-2002 by age-specific population projections for 2005.
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