What Is Photodynamic Therapy for Nonmelanoma Skin Cancer?

Some types of skin cancer can be treated with special drugs and light instead of surgery and radiation. It's called photodynamic therapy (PDT). This treatment works well and has few long-term side effects. Still, it's fairly new and isn't widely offered.

What Is PDT?

Some drugs called “photosensitizing agents” weaken cancer cells when exposed to high-intensity light. With this treatment, a medicine is rubbed onto your skin as a cream. After it's been fully absorbed, a special light is applied to your skin. This then kills your cancer cells.

PDT may also break up the blood vessels that nourish cancer cells and “wake up” your immune system to help to fight the cancer.

Why Would I Need It?

Your doctor may want you to have PDT if you've been diagnosed with:

If you have several cancers in the same area or one large cancer that's not too deep, your doctor may also suggest PDT. This may mean that you can avoid surgery.

PDT has been shown to work just as well as surgery or radiation. It often costs less than other cancer treatments and doesn't appear to have long-term side effects. Any scarring it causes is often small.

Still, PDT isn't right for everyone. For instance, people with certain blood diseases shouldn't have it. It's also not safe if you have an allergy to peanuts or almonds. Oils from these are used to make the creams that are used in PDT.

What Can I Expect?

PDT is an outpatient treatment. This means that you won't have to spend the night in a hospital.

First, your doctor may need to remove any crust or scale from the area of your skin that needs to be treated. A special cream with photosensitizing agents will be applied and the area gently covered.

How long it takes for the drug to be fully absorbed by your skin cells depends on the type your doctor uses. Some only take a few hours. Others may need up to 18 hours. If you need to wait a very long time, your doctor will send you home and ask you to come back the next day.

During the next stage of this treatment, your doctor will focus a special blue or red light onto the area of your cancer for about 15 minutes. You may feel stinging or burning while this is done. To make you more comfortable, your doctor may prescribe you a pain medication to take ahead of time. You'll also be given goggles to wear to protect your eyes.


Are There Any Side Effects?

As with any cancer treatment, you may have side effects. What these are will vary from person to person. Some common ones include:

Your doctor will want to know if you have any of these side effects so she can help you manage them. Many times, photosensitivity goes away on its own about 4 to 6 days after treatment.

What's the Recovery Like?

Your skin will be very red and sore for a few days, like after a sunburn. You'll want to avoid putting anything on it for at least 48 hours. This includes aloe vera, vitamin C and most makeups and moisturizers.

PTD also makes your skin intensely sensitive to light. Because of this, your doctor will advise you to stay indoors as much as you can for the first few days after your treatment. You'll even need to avoid bright indoor light.

Make sure to cover up with protective clothing, glasses and sunscreen when you do go outside. Avoid light-colored concrete, snow or other any other surface where light may be reflected onto your skin.

It's common for any skin that was treated with PDT to blister, scale, or crust before it heals. In about 3 weeks, any scab that's formed should fall off on its own. Make sure to follow up with your doctor. In some cases, you may need more than one PDT session to make sure all the cancer is gone.

WebMD Medical Reference Reviewed by Debra Jaliman, MD on May 17, 2019



American Cancer Society: “Photodynamic Therapy.”

Cancer Research UK: “Photodynamic Therapy (PDT.)”

Mayo Clinic: “Photodynamic Therapy.”

Canadian Cancer Society: “Photodynamic therapy for non-melanoma skin cancer.”

American Society of Clinical Oncology: “Skin Cancer (Non-melanoma) Treatment Options.”

Upstate Medical University: “Photodynamic Therapy (PDT).

National Health Service (UK): “Bowen's Disease.”

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