Colon cancer in teens is rare. It is a malignant growth that originates in the colon, a part of the large intestine. It is also called colorectal cancer if colon cancer is present with rectal cancer. Although it is common in adults, this can affect any age. A one in 1000,000 incidence rate includes 2.1% of all malignancies in people below 20 (1). Sometimes the diagnosis can be delayed in teens since regular screening is only recommended for adults. Seeking early medical care if there is a family history or for digestive symptoms may help improve outcomes. Read on to know the causes, symptoms, tests, treatment, and ways to prevent colon cancer in teens.

Symptoms Of Colon Cancer In Teens 

Many teens can be asymptomatic during the initial stages of colon cancer. Also, the symptoms may vary based on the size and location of cancer. Symptoms and signs of colon cancer can include (2): The presenting symptoms and signs are similar to the more common conditions found in childhood but, because of its rarity, often leads to a delayed diagnosis and hence presents at an advanced and incurable stage. Although blood in stool can be a common symptom of bowel cancer, rectal bleeding may also occur in hemorrhoids (piles), anal fissures (tear in the mucosal lining of the anus), etc. Seek medical care if your teen has changed bowel habits or blood in the feces.

When To See A Doctor

If your teen has any persistent symptoms, then consult a doctor. You may also initiate a medical visit for early screening if you have a family history of inherited syndromes, such as Lynch syndrome or colorectal cancers. Your doctor may help you identify risk factors and arrange a screening. The doctor may refer your teen to cancer experts for detailed diagnosis and treatment if required.

What Are The Causes Of Colon Cancer In Teens?

Most patients did not have a relevant past medical or family history, with the suggestion that these cases arise as a result of spontaneous genetic mutation. The exact cause of colon cancer is unknown. Genetic changes can be a significant cause in several cases. The mutation (changes) in the cells’ DNA can make them cancerous. It can cause the cell to undergo uncontrolled and unregulated division, thus causing an accumulation of cells that form colorectal tumors (3). The cancer cells continue to multiply and invade the healthy tissues surrounding it. The cells may also metastasize (move) from the site of origin to other parts of the body via blood or lymph.

Risks Factors Of Colon Cancer

The following factors may increase the risk for colon cancer (4). Colorectal cancers are few in young people. The young-onset of bowel cancer can be due to hereditary factors and genetic alterations than other risk factors.

Diagnosing Colon Cancer In Teenagers

The doctor may order a few tests and procedures to confirm or exclude the cancer diagnosis. The tests may include the following (5).

Colonoscopy and biopsy: It consists of the visualization of the colon with a device and the collection of samples from suspected areas. These samples are sent to the laboratory for analysis.

Blood tests: It is often performed to assess the general health and the functions of the liver and kidneys. A blood test can often be useful to analyze the presence and level of carcinoembryonic antigen (CEA) that is sometimes seen in colon cancer. The level of CEA can help decide treatment and prognosis.

After the confirmation of the colon cancer, your doctor may also order imaging tests such as CT scan, MRI scan, or PET scan to determine the extent (stage) of the colon cancer. Pelvic, abdominal, and chest imaging is usually done to identify the spread and metastasis before the staging of cancer. However, the doctor may order other tests based on coexisting signs and symptoms, if any.

Stages Of Colon Cancer

The following are the stages of colon cancer (6).

Stage 0: Abnormal cells are present in the wall or mucosa of the colon, also called carcinoma in situ.

Stage I: Cancer is limited to the mucosal and submucosal lining of the colon.

Stage II: Cancer spreads beyond the colon wall without lymph node involvement. This is sub-classed into three stages based on the invasion of nearby tissue and organs.

Stage III: Cancer spreads beyond the colon wall and lymph nodes are affected.

Stage IV: Presence of metastasis in other organs or tissues of the body.

These stages are important to determine the treatment and prognosis of colon cancer. In a few cases, the exact stage of cancer is identified at the time of cancer surgery. 

Colon Cancer Treatment In Teenagers

Colorectal carcinoma treatment is based on the stage and location of cancer, along with the health status of the teen. Treatment for early stages of colon cancer can be minimally invasive surgeries, including the following (7).

Polypectomy: This is the removal of colorectal polyps during a colonoscopy. It is done for cancers that are small and contained in a polyp.

Endoscopic mucosal resection: It is the removal of cancerous polyps and lining of the colon during colonoscopy with special tools.

Laparoscopic surgery: Minimally invasive laparoscopic surgeries are performed to remove colon polyps that cannot be removed during a colonoscopy. These surgeries are performed by inserting special instruments with a camera through a small incision.

Surgeries for more advanced colon cancer may include (7):

Partial colectomy (bowel resection): This is the removal of a part of the colon where the cancer is located, along with tissues around it. Colon cancer can be located in any part of the colon, such as sigmoid colon, transverse colon, ascending colon, or descending colon. The affected area is removed and reconnected with the healthy part after the removal of cancer.

Hemicolectomy: This is the removal of the left or right segment of the colon in advanced colon cancers. 

Colostomy: This is the surgical procedure to create an opening in the abdominal wall where the content (feces) from the colon can be drained into a bag. The colostomy is often done temporarily, and after healing, the colon will be connected to the rectum.

Removal of lymph nodes: Nearby lymph nodes are removed to prevent the spread of cancer.

If the colon cancer is in a later stage with metastasis, then surgeons may recommend surgeries to relieve the blockage of colon and other symptoms, such as bleeding or pain. However, if the health status is good, then the removal of metastatic tumors is done with adjuvant chemotherapy to improve survival. 

Other treatments 

Treatments other than surgery for colon cancer include the following.

Chemotherapy: It is the treatment of cancer using drugs that can kill cancer cells. Chemotherapy includes drugs like 5-chlorouracil, leucovorin, and cisplatin can be given before surgery to reduce tumor growth, thus making the surgery less complicated. Post-surgical chemotherapy is given to larger cancers with lymph node involvement. It can destroy cancer cells and prevent spread (metastasis) of cancer to other tissues and organs. It may also be done to relieve symptoms (8).

Radiation therapy: This uses energy sources such as X-rays and protons to destroy cancer cells. It can be done before surgery to shrink large cancer or to relieve symptoms if surgery cannot be done (9).

Targeted drug therapy: This is treatment using specific drugs to block growth and metastasis of cancer. These drugs can target growth factors, proteins, or genes of cancer cells. It may often be combined with chemotherapy (10).

Immunotherapy (biologic therapy): This treatment uses drugs that boost the body’s immune system to fight cancer (11).

Chemotherapy and radiotherapy can be used alone or along with surgery to improve outcomes or relieve symptoms in end stages of colorectal cancer. Supportive care or palliative care is given to relieve pain and other symptoms. This helps improve the quality of life. It can be given alone or with other treatments. 

Complications Of Colon Cancer In Teens

Acute complications of colon cancer can include (12):

Bleeding: This may lead to anemia and peripheral circulatory failure due to blood loss. Severe rectal bleeding can result in kidney dysfunction and may present with azotemia, which is an increased amount of nitrogen in the blood. Bleeding may also cause persistent fever for days or weeks due to the dysfunction of thermoregulatory functions of the body.

Obstruction: Colon cancer can often grow into the lumen of the colon and obstruct bowel movement. This may cause decreased absorption of fluid and nutrients and increased secretion of fluids to relieve obstruction, thus eventually resulting in dehydration. Obstruction may also cause dehydration and electrolyte loss due to vomiting and toxemia (blood poisoning) due to increased bacterial growth. Vomiting, distended abdomen, and dehydration can be signs of bowel obstruction. This requires immediate medical care.

Perforation: Rarely, colon cancer causes perforation of the bowel wall. This may often occur due to obstruction. Bowel perforation requires emergency surgery.

If you notice any concerning signs and symptoms in your teen, then make an appointment with the doctor for early diagnosis and treatment. It may help to avoid complications. 

Preventing Teenage Colon Cancer

The best way to prevent colon cancer and its complications is screening at an early age if the risk factors are present. Colon cancer begins as polyps (flat bumps) inside the colon. Regular screening can help to diagnose colorectal polyps and prevent them from turning cancerous. Screening for colon cancer is usually recommended around 50 years of age. However, early screening is done for high-risk groups such as those who have a positive family history. The following lifestyle changes may help to reduce the risk factors (4).

Maintain a healthy diet: A fiber-rich diet including fruits, grains, vegetables, and other micronutrients, could help prevent colon cancer and other bowel-related issues.

Physical activity: Regular exercise can be a protective factor for many diseases, including colon cancer.

Avoid smoking and excess alcohol: Teenage smoking and alcoholism could result in many health issues, including colon cancer.

According to the US National Cancer Institute, increasing protective factors and avoiding risk factors may help prevent colorectal carcinoma (4). You may seek medical care for screening and preventive treatments if you have a family history of colon cancers.

What Is The Colon Cancer Survival Rate?

Young-onset bowel cancer has a poor prognosis. It can be due to the advanced stage of disease at the time of diagnosis and the histologic features of the cancer cells. According to the SEER (surveillance, epidemiology, and end results) database, there is a five-year survival rate in 57% of the cases (1). Diagnosing cancer in your teen can be emotionally challenging for you and other family members. It is the time to make appropriate treatment decisions for your child and support them to cope with the pain and procedure.

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