UNDERSTANDING COLORECTAL CANCER

1. Colorectal Cancer: What Is It ?

Colorectal cancer is the third most frequently diagnosed cancer in men and women and the second highestcause of cancer deaths in the U.S. Yet, when found early, it is highly curable. This type of cancer occurs when abnormal cellsgrow in the lining of the large intestine (colon) or rectum. Learn more about who gets colorectal cancer, how it is detected, and what the latest treatments can accomplish.


2. Colorectal Cancer: How It Starts

Colorectal cancers often begin as polypsbenign growths on the surface of the colon. The two most common types of intestinal polyps are adenomas and hyperplastic polyps. They develop when there are errors in the way cells grow and repair the lining of the colon. Most polyps remain benign, but some have the potential to turn cancerous. Removing them early prevents colorectal cancer.


3.Risk Factors You Can’t Control

Your risk of colorectal cancer depends on genetics and lifestyle. Factors you can’t control include:

  • Age – most patients are older than 50.
  • Polyps or inflammatory bowel disease.
  • Family history of colorectal cancer.
  • History of ovarian or breast cancer.

4. Risk Factors You Can Control

Some factors that raise the risk of colorectal cancer are within your control :

  • Diet high in red, processed, or heavily cooked meats.
  • Being overweight (excess fat around the waist).
  • Exercising too little.
  • Smoking or drinking alcohol.

5. Colorectal Cancer Warning Signs

There are usually no early warning signs for colorectal cancer. For this reason it’s important to get screened. Detecting cancer early means it’s more curable. As the disease progresses, patients may notice blood in the stool, abdominal pain, a change in bowel habits (such as constipation or diarrhea), unexplained weight loss, or fatigue. By the time these symptoms appear, tumors tend to be larger and more difficult to treat.


6. Colorectal Cancer Screening

Because colorectal cancer is stealthy, screenings are the key to early detection. Beginning at age 50, most people should have a colonoscopy every 10 years. This procedure uses a tiny camera to examine the entire colon and rectum. These tests not only find tumors early, but can actually prevent colorectal cancer by removing polyps (shown here).


7.Virtual Colonoscopy

There is now an alternative to colonoscopy that uses CT scan images to construct a 3-D model of your colon. Called virtual colonoscopy, the procedure can reveal polyps or other abnormalities without actually inserting a camera inside your body. The main disadvantage is that if polyps are found, a real colonoscopy will still be needed to remove and evaluate them.


8.X-Rays of the Colon (Lower GI)

X-Rays of the colon – using a chalky liquid known as barium as a contrast agent – allow your doctor a glimpse at the interior of the colon and rectum, offering another way to detect polyps, tumors, and changes in the intestinal tissue. Shown here is an “apple coretumor constricting the colon. Like the virtual colonoscopy, any abnormalities that appear on the X-rays will need to be followed up with a conventional colonoscopy.


9. Diagnosing Colorectal Cancer

If testing reveals a possible tumor, the next step is a biopsy. During a colonoscopy, your doctor will remove polyps and take tissue samples from any parts of the colon that look unusual. This tissue is examined under a microscope to determine whether or not it is cancerous. Shown here is a color-enhanced, magnified view of colon cancer cells.


10. Staging Colorectal Cancer

If cancer is detected, it will be “staged,” a process of finding out how far the cancer has spread. Tumor size may not correlate with the stage of cancer. Staging also enables your doctor to determine what type of treatment you will receive.

  • Stage ICancer has not spread beyond the inside of the colon or rectum.
  • Stage IICancer has spread into the muscle layer of the colon or rectum.
  • Stage IIICancer has spread to one or more lymph nodes in the area.
  • Stage IVCancer has spread to other parts of the body, such as the liver, lung, or bones. This stage does NOT depend on how deep the tumor has penetrated or if the disease has spread to the lymph nodes near the tumor.

11. Colorectal Cancer Survival Rates

The outlook for your recovery depends on the stage of your cancer, with higher stages meaning more serious cancer. The five-year survival rate refers to the percentage of patients who live at least five years after being diagnosed. Stage I has a 93% five-year survival rate while stage IV has a five-year survival rate of only 8%.


12. Colorectal Cancer Surgery

In all but the last stage of colorectal cancer, the usual treatment is surgery to remove the tumor and surrounding tissue. In the case of larger tumors, it may be necessary to take out an entire section of the colon and/or rectum. The good news is that surgery has a very high cure rate in the early stages. If the cancer has spread to the liver, lungs, or other organs, surgery is not likely to offer a cure — but removing the additional tumors, when possible, may reduce symptoms.


13. Treating Advanced Colorectal Cancer

When colorectal cancer has spread to one or more lymph nodes (stage III), it can still be cured. Treatment typically involves a combination of surgery, radiation (being administered here), and chemotherapy. If the cancer comes back after initial treatment or spreads to other organs, it becomes much more difficult to cure. But radiation and chemotherapy can still relieve symptoms and help patients live longer.

14. Coping With Chemotherapy

Chemotherapy has come a long way from the days of turning people’s stomachs. Newer drugs are less likely to cause this problem, and there are also medications to control nausea if it does occur. Clinical trials continue to search for chemotherapy drugs that are more effective and tolerable.


15. Radiofrequency Ablation

Radiofrequency ablation (RFA) uses intense heat to burn away tumors. Guided by a CT scan, a doctor inserts a needle-like device that delivers heat directly to a tumor and the surrounding area. This offers an alternative for destroying tumors that cannot be surgically removed. In patients with a limited number of liver metastases that cannot be removed by surgery, chemotherapy is sometimes combined with RFA for tumor destruction.


16. Preventing Colorectal Cancer: Diet

There are steps you can take to dramatically reduce your odds of developing colorectal cancer. Researchers estimate that eating a nutritious diet, getting enough exercise, and controlling body fatcould prevent45% of colorectal cancers. The National Cancer Institute recommends a low-fat diet that includes plenty of fiber and at least five servings of fruits and vegetables per day.


17. Preventing Cancer With Exercise

Physical activity appears to be a powerful weapon in the defense againstcolorectal cancer. In one study, the most active participants were 24% less likely to have the cancer than the least active people. It didn’t matter whether the activity was linked to work or play. The American Cancer Society recommends exercising for at least 30 minutes most days of the week. (Source: Webmd.com).

COLORECTAL CANCER TREATMENT BY STAGE

For all stages of colorectal cancer, except stage IV, surgery to remove the tumor is the initial treatment. For some cancers, additional treatments, called adjuvant therapy, may be recommended.

Stage 0 Colorectal Cancer

Stage 0 colorectal cancer is found only in the innermost lining of the colon. Treatment usually involves one of the following :

  • Polypectomy or local excision to remove the tumor and a small amount of surrounding tissue, or
  • More extensive surgery (resection) to remove larger colon cancers. This may require a procedure called an anastomosis to remove the diseased part of the colon and reattach the healthy tissue to maintain bowel function

Surgery to remove all of the cancer is considered curative.

Stage I (Dukes A) Colorectal Cancer

Stage I tumors have spread beyond the inner lining of the colon to the second and third layers and involves the inside wall of the colon. The cancer has not spread to the outer wall of the colon or outside the colon.

Standard treatment involves surgery to remove the cancer and a small amount of tissue around the tumor. Additional treatments are not usually needed.

Aggressive surgery to remove all of the cancer offers a great potential for cure. The five-year survival rate for stage I colorectal cancer is 93% according to the American Cancer Society.

Stage II (Dukes B) Colorectal Cancer

Stage II colorectal cancers are larger and extend through the muscular wall of the colon, but there is no cancer in the lymph nodes (small structures that are found throughout the body that produce and store cells that fight infection).

Standard treatment is surgical removal of the cancer and an area surrounding the cancer: A person with Dukes B colorectal cancer may also be a candidate for a clinical trial looking at the use of adjuvant immunotherapy or chemotherapy. Chemotherapy may also be given as a precaution against cancer recurrence.

The five-year survival rate for Dukes B colon cancer is 78%.

Stage III (Dukes C) Colorectal Cancer

Stage III colorectal cancers have spread outside the colon to one or more lymph nodes (small structures that are found throughout the body that produce and store cells that fight infection). Tumors within the colon wall which also involve the lymph nodes are classified as Dukes Stage C1, while tumors that have grown through the colon wall and have spread to one to four lymph nodes, are called Dukes Stage C2 cancers. Those tumors which have spread to more than four lymph nodes are classified as Dukes stage C3 colon cancers.

Treatment involves :

  • Surgery to remove the tumor and all involved lymph nodes if possible.
  • After surgery, the patient will receive chemotherapy with 5-FU and leucovorin.
  • Radiation may be needed if the tumor is large and invading the tissue surrounding the colon

The five-year survival rate for Dukes C colon cancer is about 64%. Patients with one to four positive lymph nodes have a higher survival rate than people with more than five positive lymph nodes.

Stage IV (Dukes D) Colorectal Cancer

Stage IV colorectal cancers have spread outside the colon to other parts of the body, such as the liver or the lungs. The tumor can be any size and may or may not include affected lymph nodes (small structures that are found throughout the body that produce and store cells that fight infection).

Treatment may include:

  • Removal the cancer surgically or another surgical procedure to bypass the colon cancer and hook up healthy colon (an anastomosis).
  • Surgery to remove parts of other organs such as the liver, lungs, and ovaries, where the cancer may have spread.
  • Chemotherapy to relieve symptoms.
  • Erbitux, Avastin or Vectibix in combination with standard chemotherapy.
  • Clinical trials of new chemotherapy regimens, or immunological therapy.
  • Radiation to relieve symptoms.

The five-year survival rate for Dukes D Colon Cancer is about 8%.

Recurrent Colorectal Cancer

Recurrent colorectal cancer is cancer that returns after treatment. The recurrence can be local or near the area of the initial cancer, or the cancer can return in distant organs.

The liver is involved in up to 2/3 of patients who die from colorectal cancer.

Recurrence is most likely in patients with more advanced colorectal cancer.

Treatment may involve :

  • Surgery to remove the recurrences. This may lengthen lifespan and in some cases, this is curative when given with chemotherapy.
  • If the metastases can’t be removed, chemotherapy is the main treatment.
  • Clinical trials are another option.

(SourceWebmd.com).

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