The malignant cancers of the large intestine occurring in the inner walls of rectum and/or the colon are known as colorectal cancers. It is the third most common cause of cancer related deaths in The United States of America. The American Society of Cancer suggests that the risk of developing cancer in America is around 5%. It is more common in males than females.
Causes of Colorectal Cancer
These cancers occur due to unaltered growth of the cells in the colon or rectum. These may also occur with the growth of polyps in the intestine. The colorectal cancers may have several risk factors including genetic reasons, lifestyle and dietary factors like smoking, obesity, insufficient physical activity, fluid uptake or age and gender factors.Some diseases like ulcerative colitis, Crohn’s disease and other inflammatory bowel diseases may also lead to colorectal cancers. Other risk factors include some hereditary disorders like hereditary non-polyposis colon cancer and familial adenomatous polyposis.
Signs and symptoms of Colorectal Cancer
The signs and symptoms of colorectal cancer include:
- There may be a change in the bowel habits due to this disease that may include diarrhea or constipation or decrease in the stool thickness.
- One may see blood in the stools known as rectal bleeding especially in the age group of 50 or above.
- People may also feel pain or discomfort persistently along with cramps or gas.
- There might be a feeling of incomplete emptying of the bowel.
- Fatigue or weakness along with loss of appetite.
- Nausea or vomiting is also common.
- Sudden loss of weight.
Diagnosis of Colorectal Cancer
Colorectal cancers can be diagnosed by sampling of the sites with the possibility of tumor development. This is done during colonoscopy or sigmoidoscopy. Various types of imagings may be obtained to detect the extent of spread of this cancer to discover the sites affected. These include CT scans, MRIs or the new PET scan that provide a clear image of the tumor defects in the entire body. Biopsy is also performed for the microscopic level examination of the tumor tissue to study the nature of tumor. After the confirmation with colorectal cancer, staging of cancer is performed on the basis of spread.
Prevention of Colorectal Cancer
The best ways of preventing colorectal cancer is by adopting healthy lifestyles including:
- Healthy diet: it is important to eat healthy food in order to avoid the risk of developing this disease.
- Physical activity: sufficient exercise or physical activity should be a part of one’s daily routine.
- Regular screening: high risk individuals especially those with a family history should undergo regular screening tests for the same.
- Medications: medications like aspirin and celecoxib may be effective in reducing the risk. Vitamin D is another effective means of lowering the risk.
Treatment of Colorectal Cancer
The treatment for colorectal cancer includes:
- Surgical removal: early stage cancers can be removed surgically by laparoscopic surgery or open laparotomy. In case of severe cancers, surgeons may use chemotherapy to shrink the cancer before performing the surgery.
- Chemotherapy: it includes the use of drugs to prevent the spread of cancer to the lymph nodes or the other body organs, or to prevent its recurrence. The various drugs used include capecitabine, oxaliplatin, irinotecan, fluorouracil, bevacizumab and many more.
- Radiation therapy: it is usually used in combination with chemotherapy after the surgical removal in order to prevent its recurrence.
- Palliative care is given to the individuals who have severe colorectal cancers and focuses on the relief of specific symptoms.