Chemotherapy Principles

+ -Text Size

TOPICS

How is chemotherapy given?

Systemic chemotherapy

Drugs used for systemic (total body) chemotherapy can be given in these ways:

  • Oral (PO) — taken by mouth (usually as pills)
  • Intravenous (IV) — infused through a vein
  • Intramuscular (IM) — injected into a muscle
  • Subcutaneous (SQ) — injected under the skin

Some chemotherapy drugs are never taken by mouth because the digestive system can’t absorb them or because they irritate the digestive system. Even when a drug is available in an oral form (such as a pill or liquid), this method may not be the best choice. For example, some people with certain symptoms (like severe nausea, vomiting, or diarrhea) can’t swallow liquids or pills; other people may have trouble remembering when or how many pills to take. Still, chemotherapy drugs are powerful treatments, regardless of their form and the way they are administered.

The term parenteral is used to describe drugs given into a vein (intravenously or IV), muscle (intramuscularly or IM), or under the skin (subcutaneously or SQ). The IV route is the most common. IM and SQ injections are less often used because many drugs can irritate or even damage the skin and muscle tissue.

The IV route gets the drug quickly throughout the body. IV therapy may be given through a catheter placed in a vein in the arm or hand, which is called a “peripheral line.” IV drugs can also be given through a catheter placed into a larger vein in the chest, or neck which is known as a central venous catheter (CVC) or “central line.”

Central venous catheters (CVCs) or vascular access devices (VADs) may be needed.

Central venous catheters are also known as vascular access devices. Some types of catheters are put into the arm (so they’re inserted peripherally), but are threaded into a larger vein in the chest. They are used for these reasons:

  • To give several drugs at one time
  • For long-term therapy (to reduce the number of needle sticks)
  • For frequent treatments (using a CVC won’t cause as much wear and tear to the veins, potential scarring, and discomfort as numerous IVs that go into the small veins of the arms or hands)
  • For continuous infusion chemotherapy
  • To give drugs that can cause serious damage to skin and muscle tissue if they leak outside of a vein (these drugs are known as vesicants). Delivering these through a CVC provides more reliable access to a vein than a short-term IV, reducing the risk that the drug will leak outside the vein and damage tissues.

Many different types of CVCs can be used to allow an easier route for IV medicines. These CVCs have different types of catheters and ports. The type of CVC used is based on how long you’ll be getting treatment, how long it takes to infuse each dose of chemotherapy, your preferences, your doctor’s preferences, the care required to maintain the CVC, and its cost. Before you consent to a vascular access device, find out more from the doctor about the type he or she recommends and why. Devices are placed in different parts of the body and require different levels of care. Some can restrict certain activities that you normally do, and safety can be a concern as well. Each type comes with its own potential problems and complications. Ask about other options to be sure that you get the type that will work best for you while still meeting your treatment needs. Also find out if your health insurance will cover the costs of the CVC.

Types of central venous catheters or vascular access devices

    Type of device and some brand names

    Comments

 

    PICC (peripherally inserted central catheter) (pronounced “pick”)

    (Per-Q-Cath, Groshong PICC)

    Inserted in a vein in the arm and threaded up near the heart. An intermediate-term catheter which allows for continuous access for several weeks to months. No surgery is needed. Care of the external catheter and regular flushing is needed.

    Midline catheter

    (Per-Q-Cath Midline, Groshong Midline)

    Also placed in a vein in the arm, but the catheter is not threaded as far as a PICC. This catheter is used for intermediate length therapy when a regular short-term IV is not advisable or available. No surgery is needed. Care of the external catheter and regular flushing is needed.

    Tunneled central venous catheter

    (Hickman, Broviac, Groshong, Neostar)

    The catheter can have multiple separate lumens (channels or tubes) and is surgically placed in a large central vein in the chest. The catheter is tunneled under the skin, but the openings to the lumens remain outside the body. This is a long-term catheter that’s good for months to years. Site care of external catheter and regular flushing is needed.

    Implantable venous access port

    (Port-A-Cath, BardPort, PassPort, Medi-port, Infusaport)

    A drum-shaped port of plastic, stainless steel, or titanium with a silicone septum across the top. This device is surgically placed under the skin of the chest or upper arm. The attached catheter extends into a large or central vein. The port is accessed through the skin and into the septum with a non-coring needle. It’s intended for long-term use. No routine care is needed when there’s no needle in the port, but it may need to be flushed if not used for more than a month at a time.

    Implantable pump

    A titanium pump with an internal power source surgically implanted to give continuous infusion chemotherapy, usually at home. There is a refillable reservoir for continuous infusions that is accessed by sticking a needle through the skin.

Most of the time, these catheters or ports are put in while you are awake. The port or catheter insertion may be done in the treatment center, clinic, or hospital. You can check with your doctor or nurse about whether you need to limit your food and fluid intake before the procedure, and if medicine will be used to keep you comfortable. Inserting some of the vascular access devices is more involved than others, and may require medicine that lessens pain and makes you sleepy. Check with your doctor to find out if you need a friend or relative to drive you home after the procedure.

Potential problems with central venous catheters or vascular access devices that may happen when the catheter is put in:

  • Anything that’s put inside a blood vessel might damage the vessel, cause bruising or bleeding at the puncture site, or cause infection.
  • Bleeding — the doctor will do blood tests before the catheter is put in to be sure that your blood clots normally. Even with normal clotting, blood can leak out of the vein and cause bruising, pressure on other blood vessels or organs, and other problems.
  • Sometimes a condition called a pneumothorax may develop when a CVC is placed in the chest or neck. This happens when a lung is punctured and air collects in the chest outside the lung. It may cause one of the lungs to collapse. If placement is guided by ultrasound or fluoroscopy, it greatly decreases this risk.
  • Normal heart rhythm may be disturbed when the catheter is put in. This is usually only temporary and stops when the catheter position is changed. It rarely causes serious problems.
  • In rare cases, the catheter will go into an artery instead of a vein. If this happens, the catheter will have to be taken out. If there are no other complications, the artery usually heals by itself.
  • Infection may develop at the incision that is made to put in the catheter. Be sure to follow any instructions about caring for the incisions as they heal.

Potential problems with central venous catheters or vascular access devices that may happen sometime later:

  • Infection — skin infection can start where the catheter or port goes into the body. More serious bloodstream infections can also happen in some cases. The chance of infection can be minimized if you (and anyone else who handles the catheter) wash your hands before using it, change the dressing carefully, check the skin each time the dressing is changed, and use careful sterile technique when using the catheter.
  • A hole or break in the catheter may lead to a fluid leak. It’s important to not always clamp the catheter in the same spot, which can weaken that area. Never use too much force when flushing it.
  • Any type of catheter may become blocked by clotted blood. You can minimize this risk by carefully flushing the catheter as instructed. Once a catheter becomes blocked off (occluded), it sometimes can be opened by injecting certain medicines, but in some cases it may need to be removed or replaced.
  • The catheter may move or be pulled out if it’s not taped or sutured to the skin.
  • The catheter should always be clamped when not in use, and caps should be screwed on tightly to keep air from getting in the bloodstream. A large amount of air in the catheter may create an emergency that causes chest pain or shortness of breath.
  • If the vein the catheter is in gets blocked (closed off) a blood clot may develop and the arm, shoulder, neck, or head may swell. The clot may be treated with blood thinners, but in some cases, the catheter will have to be removed.

Be sure you understand the benefits and risks of having a CVC or other VAD. Know what problems to watch for, what to do about them, and when to call your doctor.

Regional chemotherapy

When there’s a need to get high doses of chemotherapy to a specific area of the body, it may be given by a regional method. Regional chemotherapy directs the anti-cancer drugs into the part of the body where the cancer is. The purpose is to get more of the drug to the cancer, while trying to minimize side effects on the whole body. Side effects will often still happen because the drugs can be partly absorbed into the bloodstream and travel throughout the body. Examples of regional chemotherapy include drugs given into these parts of the body:

  • Intra-arterial — injected into an artery that goes to a certain area of the body
  • Intravesical — infused into the bladder
  • Intrapleural — infused into the chest cavity between the lung and chest wall
  • Intraperitoneal — infused into the abdomen around the intestines and other organs
  • Intrathecal — infused into the central nervous system via spinal fluid
  • Intralesional/intratumoral — injected directly into the tumor
  • Topical — applied to the skin as a cream or lotion

Intra-arterial chemotherapy

An intra-arterial infusion allows a chemotherapy drug to be given directly to the cancerous tumor through a catheter placed in the artery that supplies blood to the tumor. This method is used to treat disease in an organ such as the liver (isolated hepatic perfusion), or to treat an extremity such as the leg (isolated limb perfusion).

The goal is to concentrate the drug in the area of the tumor and decrease systemic side effects. The catheter is attached to an implanted or portable pump. Although this approach sounds like a good idea for better effectiveness and fewer side effects, most studies have not found it to be as useful as expected. This approach is being studied for many types of cancer in clinical trials. Except for these clinical trials, it’s rarely available outside of specialized cancer centers.

Intracavitary chemotherapy

Intracavitary is a broad term used to describe chemotherapy given directly into a body cavity. The chemo drug is given through a catheter placed into one of these areas as described below.

Intravesical chemotherapy is often used for early stage bladder cancer. The chemotherapy is usually given weekly for 4 to 12 weeks. For each treatment, a urinary catheter is placed into the bladder to give the drug. The drug is kept in the bladder for about 2 hours and then drained. The urinary catheter is removed after each treatment.

Intrapleural chemotherapy is not used very often but may be helpful for some people with mesothelioma (cancer that develops in the lining of the lung), and those with lung or breast cancers that have spread to the pleura (the membrane around the lungs and lining the chest cavity). Intrapleural chemotherapy is given through chest catheters that may be connected to an implantable port. These catheters can be used to give drugs and to drain fluid that can build up in the pleural space when cancer has spread to that area.

Intraperitoneal chemotherapy has become one of the standard treatments for certain stages of ovarian cancer. It may also be used to treat some recurrent colon cancers, as well as cancers of the appendix or stomach that have spread extensively within the abdomen. Intraperitoneal chemotherapy is given through a Tenckhoff catheter (a catheter specially designed for removing or adding large amounts of fluid from or into the abdominal cavity) or through an implanted port attached to a catheter. Chemotherapy injected into the port travels through the catheter into the abdominal cavity where it’s absorbed into the affected area before entering the bloodstream. This approach can work very well, but it can also have more severe side effects than regular IV chemotherapy. The higher doses that are used, along with more gradual absorption of the drug into the body, may be part of why the side effects may be worse.

Intrathecal chemotherapy is given directly into the fluid surrounding the brain and spinal cord (the cerebrospinal fluid or CSF) to reach cancer cells in the fluid and the central nervous system (brain and spinal cord). Most chemotherapy drugs that are put into the bloodstream are unable to cross the barrier between the bloodstream and the central nervous system, called the blood-brain barrier. Intrathecal chemotherapy gets the drug directly to the central nervous system.

Intrathecal chemotherapy is given in 1 of 2 ways:

  • The chemotherapy can be given by a lumbar puncture (spinal tap) done daily or weekly. This is when a thin needle is placed between the bones of the lower spine and into the space through which the CSF flows around the spinal cord.
  • A special device called an Ommaya reservoir can be used. It’s a small, drum-like port which is placed under the skin of the skull. An attached catheter goes through the skull into a ventricle (a space inside the brain filled with CSF). A special needle is put through the skin and into the port to give the chemotherapy.

Chemotherapy is given this way when it’s needed to treat cancer cells that have entered the central nervous system (this is called leptomeningeal spread). This is seen most commonly in leukemias, but also may happen with some lymphomas and advanced solid tumors like breast and lung cancers. Intrathecal chemotherapy does not help when tumors have already started growing in the brain or spinal cord.

Intralesional chemotherapy

Intralesional chemotherapy refers to the drug being injected directly into the cancerous tumor. It may be used for tumors that are in or under the skin, and rarely for tumors that are on an organ inside the body. It’s only possible when the tumor can be safely reached by a needle, and is most often used when surgery is not an option.

Topical chemotherapy

In this use, chemotherapy is applied to the skin in the form of a cream or lotion. Most often, it’s put onto skin cancers such as the basal cell or squamous cell types. It’s also used to treat pre-cancerous growths on the skin. The patient or a family member usually puts on the chemotherapy cream. It’s important to understand the schedule, know exactly how to use these potent drugs, and know what kinds of precautions to use.


Last Medical Review: 02/07/2013
Last Revised: 02/07/2013