Laser therapy for cancer treatment

Laser light is concentrated so that it makes a very powerful and precise tool. Laser therapy uses light to treat cancer cells. Here's more about laser therapy:

• Lasers can cut a very tiny area, less than the width of the finest thread. They can remove very small cancers without harming nearby tissue.

• Lasers are used to put heat on tumors to shrink them.

• Lasers are sometimes used with medicines that are activated by laser light to kill cancer cells.

• Laser beams can be bent by going through tubes for hard-to-reach places.

• Lasers can be used with microscopes to let healthcare providers see the site being treated.

How are lasers used during cancer surgery?

Laser surgery is a type of surgery that uses special light beams instead of tools, such as scalpels. There are several types of lasers. Each is used to do certain things during surgery. Laser light can be delivered either continuously or intermittently. It can be used with fiber optics to treat areas of the body that are often hard to reach. These are some of the lasers used for cancer treatment:

• Carbon dioxide (CO2) lasers. CO2 lasers can remove a very thin layer of tissue from the surface of the skin without removing deeper layers. The CO2 laser may be used to remove skin cancers and some precancerous cells.

• Neodymium:yttrium-aluminum-garnet (Nd:YAG) lasers. Nd:YAG lasers can get deeper into tissue. They can cause blood to clot quickly. The laser light can be carried through optical fibers to reach internal parts of the body. For example, the Nd:YAG laser can be used to treat throat cancer.

• Laser-induced interstitial thermotherapy (LITT). LITT uses lasers to heat certain parts of the body. The lasers are directed to areas within body tissues that are near a tumor. The heat from the laser raises the temperature of the tumor. That shrinks, damages, or kills the cancer cells.

• Argon lasers. Argon lasers pass only through outer layers of tissue, such as skin. Argon lasers can be used to treat skin problems or in eye surgery. Photodynamic therapy (PDT) uses argon laser light to activate chemicals in the cancer cells.

What is photodynamic therapy?

PDT can destroy just cancer cells and leave most healthy cells alone. It is used to treat certain cancer tumors. PDT is also called photoradiation therapy or photochemotherapy. It uses a combination of a light source and a photosensitizing medicine activated by light. The medicine is often injected into the blood. It collects more in cancer cells than in normal cells. When the laser's light is focused directly on the tumor, the cancer cells absorb the light. A chemical reaction occurs that kills the cancer cells.

The FDA has approved the use of PDT for certain types of cancer that are found just under the skin or in the lining of certain organs. This is because PDT can only pass through a limited tissue depth. Cancer types that may be treated with PDT are cancer of the esophagus, nonsmall cell lung cancer, and a precancerous skin lesion (actinic keratosis). PDT may have fewer side effects than other treatments. It can also be used again and again at the same site if needed.

Major side effects of PDT are sensitivity to light and swelling at the treatment site. Both the eyes and skin are affected by light sensitivity. This may last up to 3 months after treatment. Swelling can cause pain. The swelling also may make it hard to swallow or breathe, depending on the location of treatment. Other side effects may occur. They depend on the area being treated. A small amount of damage may also occur in healthy tissue. As each person is different, so is their reaction to treatment. Side effects may be severe or mild. Or you may not have any. Talk with your cancer care team about any or all possible side effects before the treatment starts.

What cancers may be treated with laser therapy?

Lasers are used in surgery for certain types of cancer because these often have a special requirement that only lasers can meet. For instance, the laser can reach a hard to treat area, apply heat, or cut only a very small area. They may be used for:

• Vocal cords

• Esophagus

• Cervix

• Skin

• Lung

• Vagina

• Vulva

Laser surgery is also used for palliative surgery in people with cancer. Palliative surgery can help the person feel better and more comfortable or function better even though the surgery may not treat the cancer. An example of this type of surgery may involve removing a growth that is making it hard for a person to eat.