Colon Cancer Screening in Sugar Land, Texas

Early Detection to Help Protect Your Colorectal Health

Colon cancer screening can detect precancerous polyps and colorectal cancer before symptoms develop. Finding and removing certain polyps may prevent cancer, while detecting colorectal cancer at an early stage can provide more treatment options and improve outcomes.

Dr. Gregory L. Shannon is a board-certified gastroenterologist serving patients in Sugar Land, Texas. He has a particular clinical interest in colon cancer prevention and colon polyps and provides personalized screening recommendations based on each patient’s age, medical history, family history, and individual risk factors. Contact Dr. Shannon’s office for an appointment today!

Introduction

Colon cancer screening comprises a variety of diagnostic tests to detect polyps and early cancers in the colon (large intestine). The large intestine, also known as the large bowel, is the last section of the gastrointestinal tract and the digestive system. It includes the colon, rectum, and anus. Colon cancer screening can detect abnormalities and address them before the cancer develops or spreads. Regular screenings may decrease the risk of death and complications caused by colorectal cancer.

Indications

Almost all colon cancers begin as benign or noncancerous polyps, some of which may slowly develop into cancer. Colon cancer screening can detect these polyps and early cancers.

Colon cancer is the uncontrolled division of abnormal cells in the large intestine. Cancer of the colon develops from one or more polyps, small and non-cancerous growths of tissue. The cancer usually begins in the glands lining the colon and rectum. The initial non-cancerous tumor gradually develops into cancer which spreads to nearby tissues, lymph nodes or distant organs (in the later stages), disrupting their function.

Although colon cancer can affect people of all ages, it is more common in those 60 years and over. Certain factors that increase the risk of developing colon cancer include alcohol, smoking, high fat intake, a family history of colon cancer, the presence of polyps, and advanced age (>60 years).

Screening Tests

Colon or colorectal cancer can often be averted through regular screenings that can detect polyps before they become cancerous. In general, people with an average risk should start screening at age 45. There are several tests used to screen for colon cancer, including:

• Stool Tests:

  Polyps in the colon and smaller cancerous growths can cause small amounts of bleeding not visible to the naked eye. The most common test for detecting this hidden blood is the fecal occult blood test (FOBT), which looks for hidden (occult) blood in the stool. The test involves microscopic analysis of your stool in a laboratory.

  Two related tests are the stool DNA test (sDNA) and fecal immunochemical test (FIT). The stool DNA test examines DNA from an individual’s stool sample to check for cancer. It uses DNA changes that occur in the polyp or cancer to determine if a colonoscopy should be performed. The fecal immunochemical test analyzes antibodies to detect blood in the stool.

• Sigmoidoscopy:

  A sigmoidoscopy is a diagnostic procedure to inspect the inner lining of your rectum and lower end of the large intestine (sigmoid colon) for abnormalities such as tumors or polyps using a device called a sigmoidoscope - a thin, flexible tube with a tiny camera and light source at one end.

  The procedure involves placing the tube into your anus and moving it slowly through your rectum and into the sigmoid colon. As the test only looks at the lower end of the large intestine, it may fail to detect cancers that are located higher in the large intestine.

• Colonoscopy:

  A colonoscopy is similar to a sigmoidoscopy, but the whole colon can be seen. A colonoscopy is performed under general anesthesia. The colonoscope (a flexible tube with a small camera and lens attached at one end) is inserted into the rectum and gently moved up through the colon until it reaches the cecum (the junction of the small and large intestine).

  The colonoscope is then withdrawn very slowly as the camera displays images of the colon and rectum on a monitor. Polyps or growths can also be removed during the colonoscopy, to be sent later for analysis.

• Barium Enema:

  A barium enema is an X-ray exam that can detect changes or abnormalities in the large intestine. During a barium enema test, a technologist fills your colon with barium liquid through an enema, and a static X-ray or fluoroscopy (live X-ray imaging) is performed.

  The barium allows your doctor to see the inner surface of the colon and rectum to detect polyps or cancerous areas. A double-contrast barium enema employs two types of barium for more detailed images.

• Computed Tomography (CT or CAT) Colonography:

  CT colonography, sometimes referred to as virtual colonoscopy, is a screening technique in which a CT scan creates cross-sectional pictures of the abdominal organs, enabling your physician to identify changes or abnormalities in the colon and rectum.

  To help produce clear pictures, a catheter (small tube) is placed inside your rectum to fill your colon with air or carbon dioxide. CT colonography may be a more suitable option for individuals who cannot have a traditional colonoscopy due to the risk of anesthesia.

• Capsule Endoscopy:

  Capsule endoscopy is a diagnostic procedure that involves swallowing a small, capsule-sized camera that captures video of the inside of your intestines as it passes through the gastrointestinal (GI) tract. This method is still under study and is not part of standard screening at this juncture.

Summary

Colon or colorectal cancer is currently the second-highest cause of cancer death in the United States. However, when diagnosed early, many cases of colon and rectal cancers can be treated effectively. The ideal way to reduce your risk of colon cancer is to have regular colon cancer screenings.

For individuals at average risk, physicians normally recommend starting screenings (usually colonoscopies) at age 45 and continuing them until age 75, at which point the need for screenings is reassessed.

Why Choose Dr. Gregory L. Shannon for Colon Cancer Screening?

Personalized Screening and Preventive Gastroenterology Care

Colon cancer screening is not a one-size-fits-all process. The most appropriate test and screening schedule depend on your age, health, previous screening results, family history, and personal risk factors. Dr. Gregory L. Shannon helps patients understand their options and select an appropriate screening strategy.

When a colonoscopy is recommended, the examination allows Dr. Shannon to inspect the colon and rectum and remove suitable polyps during the same procedure. Findings from the examination help determine whether and when additional screening or surveillance is needed.

Patients Can Expect:

• Screening recommendations based on individual colorectal cancer risk
• Evaluation of personal and family health history
• Discussion of colonoscopy and noninvasive screening options
• Colonoscopy when medically appropriate
• Removal or biopsy of suitable polyps during colonoscopy
• Clear explanations of examination and pathology findings
• Personalized follow-up and surveillance recommendations
• Ongoing care for colorectal polyps and other digestive conditions

Colon Cancer Screening – FAQs

At what age should colon cancer screening begin?

Adults at average risk should generally begin colorectal cancer screening at age 45. People with a family history of colorectal cancer or advanced polyps, inflammatory bowel disease, an inherited cancer syndrome, or other risk factors may need to begin earlier.

Do I need colon cancer screening if I have no symptoms?

Yes. Colorectal polyps and early-stage cancer often cause no noticeable symptoms. Screening is intended to identify abnormalities before symptoms develop, when precancerous polyps may be removed and cancer may be easier to treat.

What tests are available for colon cancer screening?

Options include colonoscopy, fecal immunochemical testing, high-sensitivity stool blood testing, stool DNA testing, and CT colonography. Each test has different preparation requirements, testing intervals, benefits, and limitations. An abnormal non-colonoscopy test generally requires a follow-up colonoscopy.

Why is colonoscopy used for colorectal cancer screening?

Colonoscopy allows the physician to examine the entire colon and rectum directly. It can also enable suitable polyps to be removed or abnormal tissue to be biopsied during the same procedure.

How often do I need a colonoscopy?

For an average-risk adult with a normal, high-quality examination, screening colonoscopy is commonly repeated every 10 years. A shorter interval may be recommended based on previous polyps, bowel preparation quality, family history, inflammatory bowel disease, or other risk factors.

What happens if a polyp is found during screening?

Many polyps can be removed during the colonoscopy and sent to a laboratory for analysis. The number, size, location, and microscopic features of the polyps help determine when another colonoscopy should be performed.

Does a family history change when screening should begin?

It can. Having a parent, sibling, or child with colorectal cancer or certain advanced polyps may require earlier and more frequent screening. The recommended schedule depends partly on the relative’s age at diagnosis and the number of affected family members.

When can colorectal cancer screening stop?

Routine screening is generally recommended through age 75 for eligible adults. From ages 76 to 85, the decision is individualized based on overall health, previous screening history, life expectancy, and personal preferences. Screening is generally not recommended after age 85.

What symptoms require evaluation rather than routine screening?

Rectal bleeding, black stools, unexplained iron-deficiency anemia, persistent abdominal pain, unexplained weight loss, or a continuing change in bowel habits requires diagnostic evaluation. Do not wait for a routine screening appointment if you develop concerning symptoms.

Take the Next Step in Protecting Your Colorectal Health

Screening, Polyp Detection & Personalized Gastroenterology Care

Whether you are approaching age 45, are overdue for colorectal cancer screening, or have a personal or family history that may increase your risk, Dr. Shannon can help determine the appropriate next step. Contact his office in Sugar Land, Texas, for an appointment today.