Laser therapies for cancer
Laser therapies for cancer involve the use of focused light to treat various types of cancer, including skin, lung, colon, and liver cancers. These therapies can serve multiple purposes: they may be used to destroy tumors, shrink them to alleviate symptoms, or activate photosensitizing chemicals that trigger cancer cell death. The procedures can be performed as alternatives to traditional surgery, offering benefits such as reduced bleeding and a lower risk of infection due to the precision of the laser.
Preparation for laser therapy varies by the specific procedure and may include dietary restrictions or the use of antibiotics. For treatments involving photodynamic therapy, patients may receive a photosensitizing agent in advance to enhance the effectiveness of the laser. After the procedure, patients often need to avoid sunlight for a period, particularly those treated with photosensitizing chemicals.
While laser therapies tend to have fewer complications compared to conventional surgical methods, they still carry risks such as swelling, bleeding, and potential damage to surrounding tissues. The effectiveness and duration of results can differ based on the individual case, and laser treatments may be used in conjunction with chemotherapy or radiation. Overall, laser therapies represent a versatile approach in the evolving landscape of cancer treatment.
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Subject Terms
Laser therapies for cancer
DEFINITION: Laser therapies use light amplification by the stimulated emission of radiation (LASER) instead of or in addition to other treatment options. Some laser therapies are widely accepted, while many are still considered experimental.
Cancers treated: Many types of cancers, including skin cancer, eye, colon, lung, esophageal, vaginal, and liver cancers
Why performed: Laser therapy may be performed on a cancer patient for many reasons. Some laser therapies are done in place of surgery to destroy some or all of a tumor. In other cases, laser therapy may shrink a tumor to provide relief from symptoms and improve quality of life. Laser therapy may also activate photosensitizing chemicals in cancer cells to start a chemical reaction that kills the cells.
Patient preparation: The patient preparation required for laser therapy varies depending on the procedure being performed. The patient may be required to avoid eating or drinking fluids for a certain amount or may be given antibiotics to help prevent infection. A patient undergoing photodynamic laser therapy will be given a photosensitizing chemical a specified number of hours or days before the procedure is scheduled to be performed. The photosensitizing chemical is usually injected but can be applied topically in some cases.
Steps of the procedure: The actual steps differ depending on the type of procedure and laser, the size, type, and extent of cancer, and the surgeon's preferences. Laser types include Carbon dioxide (CO2) lasers, Argon lasers, and Nd:YAG (Neodymium: Yttrium-Aluminum-Garnet) lasers. The first step of photodynamic therapy (PDT) is to expose, or mostly expose, the tumor or area of cancerous cells or to introduce the laser using an endoscope. This is necessary because many lasers that activate photosensitizing chemicals cannot travel safely through thick amounts of skin, tissue, or membrane. Therefore, the laser must be very near the cells in which it will activate. The laser is directed toward the tumor or cancerous area and turned on briefly. The endoscope or other instrument is then removed. This procedure can be repeated as necessary.
When the laser is used to shrink a tumor, the laser light must reach the tumor without traveling through and damaging healthy cells, which is possible using an endoscope. The surgeon introduces the endoscope to the area and directs the laser. The beam from the laser heats the tumor cells to a point hot enough to kill them. The surgeon removes the endoscope after the desired amount of cancer cells are killed or once it is no longer feasible to treat additional cells without harming surrounding healthy tissue.
Laser surgery is similar to traditional surgery, but the surgeon uses a laser instead of a scalpel. Lasers are preferable to scalpels in some cases because they can make very thin, fine cuts, allowing increased precision. The laser beam also seals and sterilizes blood vessels as it cuts, reducing the chances of infection and minimizing bleeding. Laser surgery requires extremely specialized, costly equipment, and the surgeon must have significant training.
After the procedure: After a patient receives photosensitive chemicals to treat the cancer, it is necessary for the patient to stay out of the sun. Although the photosensitizing chemicals are generally left mainly in the cancer cells after a few days, enough residual chemicals may be present in the rest of the body to make the skin extremely sensitive to sunlight. Sometimes, the patient may be required to avoid sunlight for thirty days or more. Aftercare for other forms of laser therapy varies depending on the treatment and the treated area. Aftercare for many procedures is similar to aftercare for similar surgical procedures performed in the same location.
Risks: The risks associated with laser therapy vary. Procedures in which a laser is used to shrink or destroy a tumor, as well as those in which a laser is used to cut out all of or a portion of the tumor, have the risks normally associated with surgical procedures, which can include swelling, bleeding, infection, pain, and some risk of damage to surrounding tissue. Specific risks are also associated with using a laser to activate photosensitive chemicals. However, they are usually considered mild and vary depending on the type of laser and chemical used.
Results: The results expected from laser therapies vary depending on the type of laser treatment performed, the type and extent of the cancer, and treatment goals. When laser therapy is performed instead of surgical procedures, patients often experience less swelling and bleeding and are less likely to develop an infection. Laser procedures, however, may not last as long as other treatments and may need to be repeated. Chemotherapy and radiation treatments are often used with or after laser treatments.
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