Colon cancer, which is also referred to as colorectal cancer, occurs due to uncontrolled and abnormal cell division in the colon. Determining the stage of cancer is an essential step, when it comes to the treatment. This article provides information on the third stage of this serious medical condition.
Cancer is a serious disease that is characterized by the development of a tumor due to uncontrolled cell division. It is divided into stages, based on the size and the extent of spread of cancer. Staging helps in determining the correct treatment to control its growth in the body. Various tests and imaging procedures such as CT scan, biopsy, MRI, blood test, X-ray, etc., help in determining the stage and the suitable treatment options.
Colon cancer, which refers to the cancer of the large intestine, might sometimes be asymptomatic in earlier stages. Some of the affected individuals might experience changes in their bowel habits or other symptoms such as abdominal discomfort, weakness, unexplained weight loss, rectal bleeding, etc.
Stages of Colon Cancer
In the initial stage, which is also called Stage 0 or carcinoma in situ, the abnormal cells are found in the mucosa or the innermost layer of the colon wall. In stage 1, malignancy is detected in the colon mucosa. The abnormal cells start spreading to the layers under mucosa (submucosa). A prompt treatment during the early stages helps prevent the growth, thereby increasing the life expectancy of the patient.
The second stage of this category is divided again into three stages 2A, 2B and 2C. If cancer has spread to the outermost layer (serosa) of the colon wall, it is classified as stage 2A. Stage 2B indicates the spread through the outer wall of colon, but the cancer is still confined to the colon only. Stage 2C is characterized by the spread of cancer from colon to nearby organs.
The third stage of colon cancer is again divided into 3 stages, and the fourth stage is divided into 2 stages. Stage 4 is the most advanced stage. If it spreads to the nearby lymph nodes and nearby organs like liver, lung or ovary or to a distant lymph nodes, then it is known as stage 4A. If the growth has advanced into the lining of the abdominal wall or to more than one distant organ, then it is referred to as stage 4B.
The mutated cells can even spread to distant parts of the body through tissues or lymph vessels or through the blood by means of capillaries and veins. Spreading of cancer to other parts of the body is termed as ‘metastasis’. Due to metastasis, the number of tumors, size of tumors, and the number of sites where tumors are present increases considerably.
Stage 3 Colon Cancer
The third stage of the cancer in colon is subdivided into 3A, 3B, and 3C. Experts describe the stage as stage 3A, when the disease spreads from the mucosa to the sub-mucosa, traversing the muscular layer of the colon wall. Here, if doctors detect malignancy in at least one but not more than 3 nearby lymph nodes or the lymph nodes, then the condition is labeled as stage 3 A. If it spreads from mucosa to the sub mucosa and if it affects at least 4 but not more than 6 nearby lymph nodes, then also the stage is described as 3A.
When the cancerous cells spread from the mucosa to the serosa layer advancing beyond this layer without invading nearby organs, it is termed as stage 3B. The spread to the nearby lymph nodes (not more than 3) may form a cancerous tissue near the lymph nodes. If the cancer spreads from the mucosa to sub-mucosa and to the muscular layer of the colon, and it has invaded 7 or more nearby lymph nodes, then it is termed as ‘stage 3B colon cancer’.
If the cancer has spread through the serosa and to at least 4 but not more than 6 nearby lymph nodes or to 7 or more nearby lymph nodes without invading the nearby organs, it is described as stage 3C. In case, the cancer has spread through the serosa and to one or more lymph nodes or has formed cancerous tissue near the lymph nodes and if it has invaded nearby organs, then also the stage is referred to as 3C.
Prognosis
When diagnosed at the initial stage, the physicians might be able to implement and suggest treatment to impede its growth. The five-year survival rate for those diagnosed in the first stage is 93 percent. Stage 3 treatment options include chemotherapy, radiation therapy, surgical removal of cancer, painkillers, etc. If it is not possible to connect the two cut-ends of the colon, a stoma is arranged on the outer side of the abdomen, to which a bag can be connected to collect the waste material.
The prognosis for the disease reached to this severity depends upon the age, gender, lifestyle, diet, overall health of the patient, at what stage the cancer is diagnosed, how much of the colon is affected, how promptly it is treated, use of latest treatment options, the patient’s response to the treatment, etc.
- The five-year survival rate for stage 3 is between 44 – 83 percent, depending upon the aforementioned factors.
- The 5-year survival rate for stage 3A is 83%
- The rate for stage 3B is 64%
- The 5-year survival rate for stage 3C is 44%
Besides prompt treatment, patients also require family support. One should not lose hope.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.
