Rectal Cancer Overview, Treatment & More

Rectal Cancer

Overview

When colorectal cancer spreads outside the colon or rectum, cancer cells are often found in nearby lymph nodes. If cancer cells have reached these nodes, they may also have spread to other lymph nodes or other organs. Colorectal cancer cells most often spread to the liver.

When cancer spreads from its original place to another part of the body, the new tumor has the same kind of abnormal cells and the same name as the original tumor. For example, if colorectal cancer spreads to the liver, the cancer cells in the liver are actually colorectal cancer cells. The disease is metastatic colorectal cancer, not liver cancer. For that reason, it is treated as colorectal cancer, not liver cancer. Doctors call the new tumor "distant" or metastatic disease.

Tumors can be benign or malignant:

Benign tumors are not cancer:

Benign tumors are rarely life-threatening.
Most benign tumors can be removed. They usually do not grow back.
Benign tumors do not invade the tissues around them.
Cells from benign tumors do not spread to other parts of the body.

Malignant tumors are cancer:

Malignant tumors are generally more serious than benign tumors. They may be life-threatening.
Malignant tumors often can be removed. But sometimes they grow back.
Malignant tumors can invade and damage nearby tissues and organs.

Symptoms

A common symptom of colorectal cancer is a change in bowel habits.

Symptoms include:

Having diarrhea or constipation
Feeling that your bowel does not empty completely
Finding blood (either bright red or very dark) in your stool
Finding your stools are narrower than usual
Frequently having gas pains or cramps, or feeling full or bloated
Losing weight with no known reason
Feeling very tired all the time
Having nausea or vomiting

Most often, these symptoms are not due to cancer. Other health problems can cause the same symptoms. Anyone with these symptoms should see a doctor to be diagnosed and treated as early as possible.

Usually, early cancer does not cause pain. It is important not to wait to feel pain before seeing a doctor.

Diagnosis

If you have screening test results that suggest cancer or you have symptoms, your doctor must find out whether they are due to cancer or some other cause. Your doctor asks about your personal and family medical history and gives you a physical exam.

If your physical exam and test results do not suggest cancer, your doctor may decide that no further tests are needed and no treatment is necessary. However, your doctor may recommend a schedule for checkups.

If tests show an abnormal area (such as a polyp), a biopsy to check for cancer cells may be necessary. Often, the abnormal tissue can be removed during colonoscopy or sigmoidoscopy. A pathologist checks the tissue for cancer cells using a microscope.

The following screening tests can be used to detect polyps, cancer, or other abnormal areas.

Your doctor can explain more about each test:

Fecal occult blood test (FOBT): Sometimes cancers or polyps bleed, and the FOBT can detect tiny amounts of blood in the stool. If this test detects blood, other tests are needed to find the source of the blood. Benign conditions (such as hemorrhoids) also can cause blood in the stool.
Sigmoidoscopy: Your doctor checks inside your rectum and the lower part of the colon with a lighted tube called a sigmoidoscope. If polyps are found, the doctor removes them. The procedure to remove polyps is called a polypectomy.
Colonoscopy: Your doctor examines inside the rectum and entire colon using a long, lighted tube called a colonoscope. Your doctor removes polyps that may be found.
Double-contrast barium enema: You are given an enema with a barium solution, and air is pumped into your rectum. Several x-ray pictures are taken of your colon and rectum. The barium and air help your colon and rectum show up on the pictures. Polyps or tumors may show up.
Digital rectal exam: A rectal exam is often part of a routine physical examination. Your doctor inserts a lubricated, gloved finger into your rectum to feel for abnormal areas.
Virtual colonoscopy: This method is currently under study and available in some larger medical centers. It uses a type of CT scanning to image the inside of the colon.

Treatments

The choice of treatment depends mainly on the location of the tumor in the colon or rectum and the stage of the disease. Treatment for colorectal cancer may involve surgery, chemotherapy, biological therapy or radiation therapy. Some people have a combination of treatments. These treatments are described below.

Surgery

Surgery is the most common treatment for colorectal cancer.

Colonoscopy: A small malignant polyp may be removed from your colon or upper rectum with a colonoscope. Some small tumors in the lower rectum can be removed through your anus without a colonoscope.
Laparoscopy: Early colon cancer may be removed with the aid of a thin, lighted tube (laparoscope). Three or four tiny cuts are made into your abdomen. The surgeon sees inside your abdomen with the laparoscope. The tumor and part of the healthy colon are removed. Nearby lymph nodes also may be removed. The surgeon checks the rest of your intestine and your liver to see if the cancer has spread.
Open surgery: The surgeon makes a large cut into your abdomen to remove the tumor and part of the healthy colon or rectum. Some nearby lymph nodes are also removed. The surgeon checks the rest of your intestine and your liver to see if the cancer has spread.

Chemotherapy

Chemotherapy uses anticancer drugs to kill cancer cells. The drugs enter the bloodstream and can affect cancer cells all over the body.

Anticancer drugs are usually given through a vein, but some may be given by mouth. You may be treated in an outpatient part of the hospital, at the doctor's office, or at home. Rarely, a hospital stay may be needed.

Biological Therapy

Some people with colorectal cancer that has spread receive a monoclonal antibody, a type of biological therapy. The monoclonal antibodies bind to colorectal cancer cells. They interfere with cancer cell growth and the spread of cancer. People receive monoclonal antibodies through a vein at the doctor's office, hospital, or clinic. Some people receive chemotherapy at the same time.

During treatment, your health care team will watch for signs of problems. Some people get medicine to prevent a possible allergic reaction. The side effects depend mainly on the monoclonal antibody used. Side effects may include rash, fever, abdominal pain, vomiting, diarrhea, blood pressure changes, bleeding, or breathing problems. Side effects usually become milder after the first treatment.

Radiation Therapy

Radiation therapy (also called radiotherapy) uses high-energy rays to kill cancer cells. It affects cancer cells only in the treated area.

Doctors use different types of radiation therapy to treat cancer. Sometimes people receive two types:

External radiation: The radiation comes from a machine. The most common type of machine used for radiation therapy is called a linear accelerator. Most patients go to the hospital or clinic for their treatment, generally 5 days a week for several weeks.
Internal radiation (implant radiation or brachytherapy): The radiation comes from radioactive material placed in thin tubes put directly into or near the tumor. The patient stays in the hospital, and the implants generally remain in place for several days. Usually they are removed before the patient goes home.
Intraoperative radiation therapy (IORT): In some cases, radiation is given during surgery.

Causes

No one knows the exact causes of colorectal cancer. Doctors often cannot explain why one person develops this disease and another does not. However, it is clear that colorectal cancer is not contagious. No one can catch this disease from another person.

Research has shown that people with certain risk factors are more likely than others to develop colorectal cancer. A risk factor is something that may increase the chance of developing a disease.

Studies have found the following risk factors for colorectal cancer:

Age over 50: Colorectal cancer is more likely to occur as people get older. More than 90 percent of people with this disease are diagnosed after age 50. The average age at diagnosis is 72.
Colorectal polyps: Polyps are growths on the inner wall of the colon or rectum. They are common in people over age 50. Most polyps are benign (not cancer), but some polyps (adenomas) can become cancer. Finding and removing polyps may reduce the risk of colorectal cancer.
Family history of colorectal cancer: Close relatives (parents, brothers, sisters, or children) of a person with a history of colorectal cancer are somewhat more likely to develop this disease themselves, especially if the relative had the cancer at a young age. If many close relatives have a history of colorectal cancer, the risk is even greater. Genetic alterations: Changes in certain genes increase the risk of colorectal cancer.
Hereditary nonpolyposis colon cancer (HNPCC) is the most common type of inherited (genetic) colorectal cancer. It accounts for about 2 percent of all colorectal cancer cases. It is caused by changes in an HNPCC gene. Most people with an altered HNPCC gene develop colon cancer, and the average age at diagnosis of colon cancer is 44.
Familial adenomatous polyposis (FAP) is a rare, inherited condition in which hundreds of polyps form in the colon and rectum. It is caused by a change in a specific gene called APC. Unless FAP is treated, it usually leads to colorectal cancer by age 40. FAP accounts for less than 1 percent of all colorectal cancer cases.

Family members of people who have HNPCC or FAP can have genetic testing to check for specific genetic changes. For those who have changes in their genes, health care providers may suggest ways to try to reduce the risk of colorectal cancer, or to improve the detection of this disease. For adults with FAP, the doctor may recommend an operation to remove all or part of the colon and rectum.

Personal history of cancer: A person who has already had colorectal cancer may develop colorectal cancer a second time. Also, women with a history of cancer of the ovary, uterus (endometrium), or breast are at a somewhat higher risk of developing colorectal cancer.
Ulcerative colitis or Crohn's disease: A person who has had a condition that causes inflammation of the colon (such as ulcerative colitis or Crohn's disease) for many years is at increased risk of developing colorectal cancer.
Diet: Studies suggest that diets high in fat (especially animal fat) and low in calcium, folate, and fiber may increase the risk of colorectal cancer. Also, some studies suggest that people who eat a diet very low in fruits and vegetables may have a higher risk of colorectal cancer. However, results from diet studies do not always agree, and more research is needed to better understand how diet affects the risk of colorectal cancer.
Cigarette smoking: A person who smokes cigarettes may be at increased risk of developing polyps and colorectal cancer.

Getting Help

Every cancer diagnosis is different, just as every person who is diagnosed with cancer is different. Cancer knows no barriers to race, age, or social group. However there is one thing that each and every person who is diagnosed with cancer will have in common: help with fighting and beating the disease.

Life after being diagnosed with cancer will be different for everyone. Some people will have minimal disease and it will be a short chapter of their lives, while others will have a diagnosis that will change the course of the rest of their lives. Cancer diagnoses can change relationships, your routines, your work and home life. One thing is certain, no one person’s experience will be exactly the same. There are however, plenty of resources to learn about what life was like for other people, and what they did to achieve balance, maintain their health and personal life, keep peace of mind, and enjoy their lives with or after cancer.

Clinical Trials

The search for a cure for cancer is an ongoing, constant battle. Clinical trials are the basis upon which new treatments and medications are proven to help the fight against cancer, or if researchers should pursue another tactic. The advancement of medicine depends on willing and able cancer patients to volunteer for experimental treatments so that future generations will have proven and effective cures. Not every patient with cancer will be eligible for a clinical trial, as the scientific method needs specific patients with specific types of cancers. However, patients who are selected for trials may benefit from being at the cutting edge of new research, and gain time they otherwise might not have had.

The National Cancer Institute at the National Institutes of Health has a comprehensive database of over 10,000 ongoing clinical trials that both help advance medicine and help patients.

Financial Help

Unfortunately, cancer treatment can be costly, even if a patient has very comprehensive health insurance. For patients who do not have health insurance, the cost of treatment may seem insurmountable. Fortunately many pharmaceutical companies offer cost assistance to help make treatment more affordable. The National Comprehensive Cancer Network has compiled a Virtual Reimbursement Room where patients can find information for accessing financial help with their treatment costs.

Related Information

Doctors all over the country are conducting many types of clinical trials (research studies in which people volunteer to take part). Doctors are studying new ways to prevent, detect, and treat colorectal cancer.

Clinical trials are designed to answer important questions and to find out whether the new approach is safe and effective. Research already has led to advances, and researchers continue to search for more effective approaches.

People who join clinical trials may be among the first to benefit if a new approach is shown to be effective. And if participants do not benefit directly, they may still make an important contribution to medicine by helping doctors learn more about the disease and how to control it. Although clinical trials may pose some risks, researchers do all they can to protect their patients.

Research is being done to test whether certain dietary supplements or drugs may help prevent colorectal cancer. For example, researchers across the country are studying vitamin D and calcium supplements, selenium supplements, and the drug celecoxib, in people with polyps.

Scientists are testing new ways to check for polyps and colorectal cancer. NCI-supported researchers are studying virtual colonoscopy. This is a CT scan of the colon. It makes x-ray pictures of the inside of the colon.

Living With

Your experience with cancer will depend on the type of cancer you have, your choices of treatment and the lifestyle you lead. Be sure to speak with your Doctor about the side effects of your disease and the treatments you choose. Your Doctor will be able to consult with you on realistic lifestyle expectations.