Disclaimer: Consult with a doctor before deciding on a treatment plan for cancer or any other disease.
Blue light therapy and photodynamic therapy share certain features in common. The primary difference between the two is that photodynamic therapy requires the use of an activator/sensitizer. Blue light therapy is generally used to treat skin conditions. In 2002, the FDA approved ClearLight for use in the treatment of acne though it can also be used to treat cancer.
Blue light therapy is a cancer treatment that is specifically used for melanoma and other skin cancers. Because blue light can only reach those areas that it can directly illuminate, internal cancers aren’t often treated with blue light since doing so would require surgery. Blue light therapy is related to photodynamic therapy .
Blue light therapy is a newer technique for killing skin cancers and treating other skin conditions. The technique was approved by the FDA in 2002 under the name ClearLight, and is used often in dermatology clinics specifically for the treatment of acne . Photodynamic therapy (a similar treatment) also uses blue light in the treatment of cancer and can be a more effective treatment option for some patients, but it is often used in conjunction with chemotherapy or radiation in the United States. Other countries offer photodynamic therapy and blue light therapy as a stand-alone treatment; one example is the Hope4Cancer clinic in Tijuana, Mexico .
Safety and Effectiveness
The sensitizing agent used at the Hope4Cancer clinic for photodynamic therapy (a similar treatment to blue light therapy) is non-toxic and naturally occurring. The sensitizer is called SP Activate, and comes from a chlorophyll derivative of seaweed. It acts by gaining access to cancer cells and then waiting for specific lights or sounds; after the “cue” from light or sound reaches the sensitizer, it releases an oxygen molecule that kills the cancer cell. Because SP Activate targets cancer cells, healthy cells aren’t generally affected. Any healthy cells that are affected release the sensitizer after a day or two with no side effects . (NOTE: The photodynamic therapy used at Hope4Cancer is not purely blue light therapy, but rather photodynamic therapy which also uses light to kill cancer cells. In some cases this treatment may be recommended for increased penetration into cancer cells.)
Because it uses light only in its treatment of skin cancers, blue light therapy doesn’t cause any known side effects. The only risk with blue light therapy is eye damage, which may occur if proper eye protection isn’t worn during the treatment; most treatment kits/clinics will provide appropriate eyewear, so this risk is extremely low. Photodynamic therapy may be marketed as “blue light therapy,” and the use of sensitizing agents in this treatment carries a few generally mild side effects that include swelling, discomfort, redness, blistering, and/or bruising at the treatment site. These side effects usually go away within 3-14 days. Infections may occur and depending on the treatment site, difficulty breathing due to swelling from blue light therapy or photodynamic therapy may also occur .
Blue Light Therapy vs. Photodynamic Therapy
If patients desire blue light therapy exclusively, and not photodynamic therapy, the major difference between the two has to do with sensitizing agents. Blue light therapy and photodynamic therapy (PDT) are similar, closely related treatments for cancer, however they are not the exact same treatment. The primary difference between the two treatments is that PDT uses a sensitizing agent to “prime” the area to be treated (sometimes this sensitizer is taken internally), while blue light therapy uses only healing light targeted at the necessary location .
How Blue Light Therapy is Administered
Blue light therapy is administered as an outpatient procedure, and can even be done at home without the direction of a professional. The skin is first cleansed with a mild, non-medicated soap to remove any impurities and then left until it is completely dry. Then, the affected area is illuminated with 415nm (+/-) blue light for 10-20 minutes. No pain is felt during the procedure, and no side effects are present after the treatment. It may be done as regularly as the patient feels is necessary since the light doesn’t cause any adverse effects on skin .
Other Important Information
Blue light therapy can also be used to treat other conditions such as:
- Periodontal disease
- Neonatal jaundice
- Staph infections
- Mood disorders
- Disordered sleep cycles.
Blue light therapy alone can be effective on some skin cancers, but in other situations some patients may benefit from the use of photodynamic blue light therapy that uses sensitizers to help the light penetrate and destroy cancer cells . Additionally, the use of sensitizing agents may allow the blue light to penetrate deeper into the body and reach cancers below the skin .
 Gotter, Ana (2017). Blue Light Therapy. Retrieved May 4, 2018 from: https://www.healthline.com/health/blue-light-therapy
 Liu, Vincent; Swick, Brian L (2017). Blue-Light Therapy Warding Off Skin Cancer. Retrieved May 4, 2018 from: https://uihc.org/health-library/blue-light-therapy-warding-skin-cancer
 Bollinger, Ty M (2016). The Truth About Cancer. Hay House Inc.: New York City
 N.A. (2008). Blue Light Therapy and Photodynamic Therapy (PDT) Are Not the Same Thing. Retrieved May 4, 2018 from: https://lighttherapyoptions.com/blue-light-therapy-and-photodynamic-therapy-pdt-are-not-the-same-thing/
 N.A. (n.d). Your Complete Guide to Blue Light Therapy. Retrieved May 4, 2018 from: https://lighttherapyoptions.com/light-therapy/blue-light-therapy/