With most cancers, patients  may be required to undergo a course of chemotherapy treatment, and it can be administered in different ways. 

Chemotherapy uses cytotoxic drugs which help destroy cancer cells within the body. These drugs may either be given orally in tablet form, or intravenously, directly into your bloodstream.

How is chemotherapy administered?

Oral chemotherapy
Some chemotherapy drugs are available as tablets, which you can swallow at home as prescribed by your specialist. If you are being treated in this way then you only need to go to the hospital for routine checkups and blood tests. However it is important to make sure you immediately report any side-effects or unusual symptoms to your doctor.

Intravenous (IV) injection
In this method of treatment, the drugs are injected directly into your vein. There are many different types of injection therapies, and so the timescale for receiving the drugs can vary over a few minutes up to even a few days.

Usually a small tube is inserted into your hand, arm, or chest, in order to administer the drug. Sometimes these can stay in place for many months at a time, depending on the length of your treatment.

Systemic chemotherapy: Often, a cancer can spread beyond the organ is started in. In this instant, Systemic chemo will be used. This is when medication is into the veins or given by mouth, therefore entering the bloodstream and reaching all areas of the body.

Regional chemotherapy: In order to target a specific area, the regional method is used. Drugs are injected directly into an artery leading to the particular part of the body containing a tumor. This approach concentrates the dose of chemo reaching the cancer cells in that area. Side effects are limited when chemo is administered in this way, as it limits the amount reaching the rest of the body.

Hepatic artery infusion, is where chemo is given directly into the hepatic artery, and is an example of regional chemotherapy, which is sometimes used for colon cancer that has spread to the liver. This is used less often than systemic chemotherapy.

How will chemotherapy form part of my treatment?
Chemotherapy can either be used on its own, or in a combination with other types of treatment, as you will discuss with your specialist. The main treatment methods are as follows

  • Neo-adjuvant is the use of Chemotherapy prior to an operation, in order to shrink the tumour(s) in order that there’s a better chance of it being successfully removed.
  • Adjuvant chemotherapy is given after surgery to destroy any microscopic cancer cells that may remain following an operation, and also to help prevent the cancer from returning.
  • First-line chemotherapy is the method which has proven to be most effective at destroying cancer cells in clinical trials and research.
  • Second-line chemotherapy is the second most effective method, which is used if the cancer has not responded to first-line treatment.
  • Third-line chemotherapy is then given if the cancer either does not respond to first-line and second-line therapy, or if these treatments then stop working.
  • Palliative chemotherapy is given when the cancer has been diagnosed as terminal; in order to relieve symptoms, slow the spread of the disease, and to prolong life.

What different types of drugs are available?
Again, you will discuss with your specialist the best treatment plan, tailored to you. Your specialist may prescribe one drug, or a combination of drugs, depending on the treatment plan you decide.

The chemotherapy drugs licensed for the treatment of bowel cancer in the UK are:

  • 5FU (5-fluorouracil)
  • Capecitabine
  • Oxaliplatin
  • Irinotecan
  • Tegafur-uracil
  • Raltitrexed (for people who cannot tolerate 5FU).

Combinations of chemotherapy drugs

  • FOLFOX ( 5FU + oxaliplatin)
  • FOLFIRI ( 5FU + irinotecan)
  • FOLFOXIRI (5FU + oxaliplatin + irinotecan)
  • CaPOX or XELOX (capecitabine + oxaliplatin)
  • CAPIRI or XELIRI (capecitabine with irinotecan)
  • DeGRAMONT/modified DeGRAMONT (combinations of 5FU and folinic acid)

Side effects of chemotherapy
Unfortunately, with this type of treatment there is a moderate risk of unwanted side-effects, however each dose of chemotherapy you receive will be ‘risk-assessed’ against your body mass and surface area in order to eliminate the risk of side-effects while still maintaining an effective treatment.

The most common symptoms may include nausea and vomiting, diarrhoea, febrile neutropaenia (fever), loss of appetite, and a change in the way you taste and smell, or sensitivity to hot or cold food. Additionally for those who have been prescribed Oxaliplatin there is the risk of peripheral neuropathy (nerve damage). Chemotherapy works by attacking cells that are dividing too quickly. But other cells in the body, such as those in the bone marrow, the lining of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also likely to be affected by chemo, which can lead to certain side effects that many of us are familiar with.

Side effects can vary depending on the dosage required and the type of cancer. Common side effects can include:

  • Diarrhoea
  • Nausea and vomiting
  • Mouth sores
  • Loss of appetite
  • Low blood counts

Chemo can affect the blood forming cells of the bone marrow, leading to low blood cell counts. This can lead to: Increased chance of infections (too few white blood cells), easy bruising or bleeding (too few blood platelets), fatigue (too few red blood cells).

Many side effects of chemo are only short-term, and you will notice them decreasing as it comes to the end of your treatment.  It is important to be aware of changes occurring to your body during chemo, and any side effects you may be experiencing should be noted. Once you have informed your medical team, they can then give you the correct medication to treat these side effects. It may also be necessary to decrease or delay any further chemotherapy treatment in order to let the effects settle down.

Older people seem to be able to tolerate some types of chemotherapy for colorectal cancer fairly well. There is no reason to withhold treatment in otherwise healthy people simply because of age.