Rectal Cancer

The rectum is the last part of the colon that connects the large intestine to the anus, and its main function is to store the stool to be expelled from the body. The rectum is approximately the last 12-15 cm of the large intestine. It starts in the last part of the colon and ends when it reaches the short and narrow passage that reaches the anus. It consists of 3 layers. The mucous part, which consists of glands that secrete mucus to facilitate the passage of stool, covers the inner surface of the rectum. The layer called muscularis propria, which forms the middle layer of the rectum wall, consists of muscles that provide contraction. The last part of the rectum is the fat layer. Apart from these three sections that make up the rectum, lymph nodes surround the rectum.

What is Rectal Cancer?

Rectal cancer is usually caused by polyps in the lining of the rectum. Cancer of the rectum and colon is often defined as “Colorectal cancer”.

What Causes Rectal Cancer?

The exact cause of rectal cancer is not known, but there are many risk factors that lead to rectal cancer.

• The majority of rectal cancers occur in advanced age.
• Alcohol and cigarette consumption increase the risk of rectal cancer.
• High-fat diet of animal origin may be the cause of rectal cancer.
• A history of colorectal cancer or polyps can cause rectal cancer.
• Chronic inflammatory diseases of the colon and rectum, such as ulcerative colitis and Crohn’s disease, increase the risk of rectal cancer.
• Genetic syndromes such as hereditary nonpolyposis colorectal cancer (Lynch) and familial adenomatous polyposis (FAP) are among the causes of rectal cancer.

• A sedentary lifestyle and obesity
• Receiving radiotherapy for cancer treatment, especially to the abdomen, can cause rectum and colon cancer.
• Diabetes
• Colon and rectal cancer in the family, especially in first-degree relatives, is an important cause of rectal cancer.

How Is Rectal Cancer Diagnosed?

• Routine screening programs should be applied to detect rectal cancer early. Starting routine screening at the age of 50 in individuals without risk factors is vital for early detection of rectal cancer. In those with risk factors, the onset of screening age may be earlier. Rectal cancer is usually diagnosed during check-ups after rectal bleeding or iron deficiency.
• Colonoscopy is the most commonly used method in screening programs and diagnosis. During colonoscopy, small tissue samples can be removed from suspicious-looking areas. Laboratory analysis of tissue samples removed for biopsy helps diagnose rectal cancer.

Treatment of Rectal Cancer

Treatment planning is made after the stages and grade of rectal cancer are determined. Planning in the treatment of rectal cancer is based on the stage and grade of the cancer, the location of the tumor in the rectum, its size, the patient’s age and general health.

Rectal Cancer Chemotherapy and Radiotherapy Treatment

Rectal cancer chemotherapy treatment is usually performed with two or more drugs that target cancer cells. In rectal cancer, chemotherapy and radiotherapy can be used before the operation as well as after it. While surgery may be the only necessary step in the treatment of stage 1 rectal cancer, the risk of recurrence after surgery is low in stage 1 rectal cancer, so chemotherapy is generally not recommended. In the 2nd and 3rd stages of rectal cancer, chemotherapy and radiotherapy are treated after the surgery in order to prevent the cancer from recurring. In patients with rectal cancer in stage 2 and stage 3, chemotherapy and radiotherapy treatment to shrink the tumor can be performed before the operation.

Rectal Cancer Surgery

Surgery is one of the most commonly used methods in the treatment of rectal cancer. Planning in rectal cancer surgery is done according to the location and size of the tumor.

Rectal cancer surgery can be classified in two groups as breech-preserving rectum surgery and rectal surgery requiring breech loss.

In rectal cancer surgery;

• end colostomy
• coloanal anastomosis
• Low anterior resection
• Local excision – Local or Transanal Excision – Transanal Endoscopic Microsurgery
• Intraoperative radiation therapy (IORT).
• Abdominoperineal Excision (APR) – Extra-Levator Abdominoperineal Excision
• polypectomy
• Radiofrequency ablation
• cryosurgery

Surgical techniques such as minimally invasive surgery can be used

Rectal Cancer Stages

The degree of rectal cancer and the stage of rectal cancer are important for the treatment to be applied. Knowing the extent of rectal cancer can give an idea about how fast the cancer can grow and the likelihood of metastasis.

In low-grade rectal cancer, the cells are abnormal but look like normal cells. Low-grade rectal cancer tends to grow slowly and is less likely to metastasize. High-grade rectal cancer also has more undifferentiated cancer cells. These cells tend to grow rapidly in high-grade rectal cancer and are also more likely to metastasize than low-grade cancers.

Staging is important for planning rectal cancer treatment. While staging of rectal cancer;

• How deep the tumor is in the wall of the rectum
• Whether there is cancer in the lymph.
• Whether rectal cancer has metastasized to other organs such as the lung or liver.

Rectal cancer stages are evaluated in 5 groups.

• Rectal Cancer Stage 0: Cancer cells are only found in the inner lining of the colon or rectum, called the mucosa. Cancer cells have not penetrated the muscle layer of the mucosa.
• Rectal Cancer Stage 1: The tumor has spread to the connective tissue layer surrounding the mucosa or the thick outer muscle layer of the rectum.
• Rectum Cancer Stage 2: Rectal cancer stage 2 is handled in three stages.
  • Rectal Cancer 2 Stage- A; The cancer has reached the outermost layer of the rectum wall and has not spread to the surrounding organs. There is no metastasis to lymph and distant organs.
  • Rectal Cancer 2 Stage- B: The cancer has invaded all layers of the rectum wall but has not spread to surrounding organs or tissues. There is no lymph or metastasis to distant organs.
  • Rectal Cancer 2 Stage- C; The cancer has extended beyond the rectal wall. It has grown into nearby organs or tissues. There is no metastasis in lymph and distant organs.
• Rectal Cancer Stage 3: The cancer has spread to nearby lymph nodes. Rectal cancer stage 3 is divided into 3 parts, depending on where the tumor has grown and how many lymph nodes it has spread.
• Rectal Cancer Stage 4: Rectal cancer stage 4 metastases to organs such as the liver or lungs. Cancer may be in only 1 organ or distant lymph nodes. It is handled in 3 stages.
  • Rectal Cancer Stage 4-A: The cancer has spread to an area or organ not close to the rectum, such as the liver, lung, ovary, or a distant lymph.
  • Rectal Cancer Stage 4-B: The cancer has spread to more than one area or organ not close to the rectum, such as the liver, lung, ovary, or a distant lymph node.
  • Rectal Cancer Stage 4-C: The cancer may have spread to the tissue lining the abdominal wall and may have spread to other areas or organs.

Rectal Cancer Nutrition

Eating a balanced diet before, during or after treatment for rectal cancer can help the person feel good and speed up the healing process.

Get your weight control. Treatments such as chemotherapy, radiotherapy, and surgery for rectal cancer can often lead to unwanted weight loss. Excessive weight loss should be avoided during treatment, as poor and unbalanced diet may reduce the body’s ability to fight infection.

Eat small, frequent meals throughout the day. Eating frequent small meals will also help reduce treatment-related side effects such as nausea, which will allow your body to absorb enough calories, protein and nutrients to tolerate the treatment.

Choose foods rich in protein. Protein helps the body repair cells and tissues, as well as helps the immune system recover from disease. Include a lean protein source at all meals and snacks. Good sources of lean protein include:

• Lean meat such as chicken, fish, or turkey
• Eggs
• Low-fat milk or dairy products, such as milk, yogurt, and cheese
• Nuts
• beans
• soy foods
• Include whole grain foods in your diet. Whole grain foods provide a good source of carbohydrates and fiber, which helps keep your energy levels high.
• Good sources of whole grain foods include:
• Rolled oats
• Whole wheat breads
• brown rice
• Whole grain pastas
• Eat a variety of fruits and vegetables every day. Fruits and vegetables offer antioxidants to the body, which can help fight cancer. Choose a variety of colorful fruits and vegetables to get the most benefits.
• Choose healthy sources of fat. Avoid fried, greasy and oily foods
• Limit sweets.
• Don’t forget to drink water. Drinking enough fluids during cancer treatment is important to prevent dehydration.
• Pay attention to changes in bowel habits. Colorectal cancer and its treatments can often cause changes in bowel habits such as diarrhea, constipation, bloating and gas. Share any changes in your bowel habits with your doctor.
• Talk to your healthcare team before taking any vitamins or supplements.