Rectal cancer is presently the third most common cancer in case of both men and women. However, the mortality rates have decreased since the 1980's because of improvements in screening.
The following are possible risk factors for rectal cancer:
Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, Such as difficulties in passing stool altered bowel habit, blood in stool etc. A history of the patient’s health habits and past illnesses and treatments will also be taken.
Digital rectal exam (DRE): An exam of the body to check general signs of health, including checking for signs of disease, Such as difficulties in passing stool altered bowel habit, blood in stool etc. A history of the patient’s health habits and past illnesses and treatments will also be taken.
Colonoscopy : A colonoscope is a tube-like instrument that helps to view or remove polyps or tissue samples if needed.
CT scan (CAT scan): A procedure that makes a sequence of comprehensive pictures of areas inside the body taken from different angles. The pictures are made by an x-ray machine. A dye is injected or swallowed to help the organs or tissues appear clear. This procedure is also called computed tomography or computerized axial tomography.
MRI (Magnetic Resonance Imaging): This procedure takes the help of a magnet, radio waves, and a computer to create detailed pictures of areas inside the body.
PET scan (Positron Emission Tomography scan): This is a procedure to locate malignant tumor cells in the body. A small quantity of radioactive glucose (sugar) is injected to get a picture of places in the body where glucose is being used. Malignant tumor cells mostly appear brighter in the picture because of their high activity.
End rectal ultrasound: This is a procedure to scrutinize the rectum and nearby organs. An ultrasound is inserted into the rectum to find high-energy sound waves (ultrasound) of internal tissues or organs. The echoes form a picture known as sonogram, which helps to identify tumours. This procedure is also called transrectal ultrasound.
Biopsy: The removal of cells or tissues for observing them under a microscope to look for indications of cancer. Tumor tissues that are removed during the biopsy are checked to see if there is any possibility of gene mutation that causes HNPCC. This helps to chalk out a plan treatment. The following tests may be used:
Reverse-transcription polymerase chain reaction (RT-PCR) test: A laboratory test in which cells in a sample of tissue are studied using chemicals to look for certain changes in the structure or function of genes.
Immunohistochemistry study: A laboratory test in which a material like antibody, dye, or radioisotope is added to tissue sample to check for the presence of certain antigens
Carcinoembryonic antigen (CEA) assay: It is used for measuring the level of CEA in the blood. After releasing CEA into the bloodstream, its amount is checked. If it is higher than normal amounts, it can be an indication of rectal cancer.
The stage of the cancer (whether it affects the inner lining of the rectum only, involves the whole rectum, or has spread to lymph nodes, nearby organs, or other places in the body).
Whether the tumor has spread into or through the bowel wall.
Where the cancer is found in the rectum.
Whether the bowel is blocked or has a hole in it.
Whether all of the tumor can be removed by surgery.
The patient’s general health.
Whether the cancer has just been diagnosed or has recurred.
Feeling that the bowel does not empty completely.
Different types of treatment are available for patients with rectal cancer.
Surgery is the most common treatment of rectal cancer. The cancer is removed using one of the following types of surgery:
Polypectomy: If the cancer is found in a polyp (a small piece of bulging tissue), the polyp is often removed during a colonoscopy.
Cryosurgery: A treatment that uses an instrument to freeze and destroy abnormal tissue, such as carcinoma in situ. This type of treatment is also called cry therapy
Local excision: If the cancer is found on the internal side of the rectum without spreading into the wall of the rectum, the cancer tissue is removed.
Resection: If the cancer has spread into the rectum wall, the section of the infected rectum nearby healthy tissue is removed. Sometimes the tissue between the rectum and the abdominal wall is also removed.
Radiofrequency ablation:The use of small electrodes that kill cancer cells. The probe can be either inserted directly through the skin or inserted through an incision in the abdomen. This is done with general anesthesia.
Pelvic exenteration: If the cancer has spread to other organs near the rectum, some organs are removed like the lower colon, rectum, and bladder . In women, the cervix, vagina, ovaries, and nearby lymph nodes may be removed. In men, the prostate may be removed.
After the cancer is removed, the surgeon will either:
Do an anastomosis (sew the healthy parts of the rectum together, sew the remaining rectum to the colon, or sew the colon to the anus)
Or make a stoma (an opening) from the rectum to the external body so that the waste can pass through it. This procedure is called colostomy and is done when the cancer is too near to the anus.
Radiotherapy uses a ray of high energy particles to wipe out cancer cells. It is required to kill cells that get left behind even after surgery. There are two types of radiation therapy: external and internal. External radiation therapy is performed outside the body with the help of a machine toward the cancer. Internal radiation therapy takes the help of a radioactive substance covered in needles, wires, seeds, or catheters that are placed near the cancer.
Chemotherapy is a cancer treatment that takes the help of drugs to impede the growth of cancer cells, either by killing them or from stopping them from dividing. It can be given either given before surgery or after surgery based on the stage of disease. Chemoembolization of the hepatic artery is a regional chemotherapy that is usually used to treat cancer spreading to the liver. The usage of chemotherapy completely depends on the type and stage of the cancer.