Is Blindness an End Stage Effect of Colon Cancer?

When caught early, a patient suffering from colon cancer could have a life expectancy of up to five years. It is important that everyone get a regular colon exam after the age of 50 so that this disease may be caught in the early stages if it is present in the body. As each stage of colon cancer develops, the life expectancy rate decreases. If you are exhibiting any of the symptoms of colon cancer, you should be examined as soon as possible.

Colon Cancer

• When malignant cells form within the colon, this is called colon cancer. People that are most prone to develop colon cancer include those over the age of 50 years old, anyone who has a history of cancer within the family, and those who have had polyps (bulging tissues) in the colon in the past. A person with Crohn's disease or who has experienced ulcers in the lining of the intestines may be more likely to develop colon cancer.

  The severity of colon cancer is categorized in five stages: stage 0, stage I, stage II, stage III and stage IV.

Symptoms

• Symptoms associated with colon cancer include blood in the stool, constipation, diarrhea, abdominal cramping, extreme fatigue, unexplained weight loss, gas pains and vomiting, according to the National Cancer Institute.

Stages

• Stage 0 of colon cancer is when the cancer is only in the inner lining of the large intestine. Ninety-five percent of people diagnosed with colon cancer at this stage have a survival rate of five years, according to the Merck online medical dictionary.

  Stage I is when the cancer spreads to the muscle of the large intestine. Ninety percent of patients diagnosed with stage I colon cancer will survive up to five years.

  Once the cancer spreads to the muscles and the outer layer of the large intestines, the patient is in stage II of colon cancer. The percentage of those diagnosed with stage II colon cancer who survive for five years ranges from 55 to 85.

  Stage III is when the cancer has spread to the lymph nodes through the outer layer of the colon. Only 20 percent to 55 percent of stage III patients survive for five years.

  The final stage of colon cancer is stage IV and only 1 percent of patients within this stage will survive for five years. By this stage, the cancer has spread to other organs such as the lungs, liver or ovaries.

Metastatic Cancer and Blindness

• Metastatic cancer is a type of cancer that can invade other areas of the body including the brain. When the brain is attacked by these cancerous cells, it can cause symptoms such as unsteadiness, headaches, seizures, and blindness.

  The Department of Medical Oncology in India states that a metastatic brain mass is typically associated with systemic cancer elsewhere in the body.

Cancer Medication and Blindness

• Bevacizumab is used along with other medicines to treat patients with metastatic carcinoma of the colon or rectum, according to the Mayo Clinic website. "Bevacizumab is a substance that helps the body fight cancer," the website says, adding, "It prevents the growth of certain types of blood vessels to cancer cells. This helps to decrease the growth of cancer cells by starving the cells of nutrients that are needed to grow."

  Bevacizumab can cause many severe side effects, including gastrointestinal perforation, slow healing of wounds, fatal bleeding, high blood pressure, and nervous system disturbance that can include headache, seizure or blindness.