Dr. Connie Pennington, MD

 

Diagnosis

 

Colorectal cancer is the third most common cancer in the US. Each year there are nearly 150,000 new cases. The most common symptom of colorectal cancer is abdominal pain, followed by a change in bowel habits, and finally rectal bleeding. Many colon cancers are found on colonoscopy in patients with no presenting symptoms.  A pathologist makes the diagnosis of colon cancer after receiving a biopsy. It is important to have a pathologic diagnosis prior to planning surgery. Some large colon polyps are treated as if they were cancers without a biopsy proven cancer being present due to the danger of the polyp turning to cancer. 

 

Staging

 

The Joint Committee on Cancer (AJCC) developed a staging system to classify colorectal cancer. Staging systems are a means for physicians to communicate with each other, and plan treatment strategies.  Briefly, there are 4 stages of colon cancer:

 

Stage 1: Cancer confined to the colon

Stage 2: Cancer penetrates the colon but does not involve lymph nodes

Stage 3: Cancer penetrates the colon and involves lymph nodes

Stage 4: Cancer is found spreading to other organs

 

Staging can sometimes be determined by CT scans before surgery, but often staging is not complete until after surgery when the lymph nodes can be examined by a pathologist. Distant metastasis in colon cancer is almost always to the liver or the lungs. Carcinoembryonic antigen (CEA) is a glycoprotein that is present is 97% of patients with metastatic colon cancer, and shows up in 30-40% of stage 1 colorectal cancer.  Controversy exists over the usefulness in following CEA levels but it is routinely ordered. Once a diagnosis of colon cancer has been made and CT scans and laboratory values have been collected, surgery is scheduled. More on pre-operative planning will be discussed in the next module.

 

Understanding Cancer Development

 

Cancer is simply an abnormal growth of cells that has escaped the body’s immune system. Although many people have contributed cancer to “bad genes” this is simply not true. Less than 3-5% of colorectal cancers are related to genetically inherited syndromes. The field of epigenetics further demonstrates that our genes are turned on and off in accordance with our interactions with the environment. This means that food exposure, chemical exposure, and the amount of exercise we get determine to a great extent if we will develop cancer. Advancing age is considered a non-modifiable risk factor, while the majority of risk factors are modifiable through life style changes. Physical stress to the body comes in many forms but typically results from dehydration, poor food choices, poor quality sleep, and a lack of exercise. In an effort to maintain homeostasis the body reacts to chronic physical stress by demonstrating a weakened immune system that “misses a growth” due to a lack of basic building blocks. Emotional stress can also contribute to a weakened immune system. Addressing and preventing physical and emotional stress to the body allows the body’s immune system to function optimally.