Esophageal Cancer: Photodynamic Therapy (PDT)
What is photodynamic therapy?
Photodynamic therapy (PDT) is a type of cancer treatment. In it, you receive a light-activated medicine that tends to collect in cancer cells. Later, the cells are exposed to a special light. This converts the medicine into a new form that kills the cancer cells.
When might photodynamic therapy be used?
Because PDT relies on light to work, it can only be used for cancers that are near the inner surface of your esophagus. It cannot reach deeper layers of the esophagus or cancer in other parts of the body. PDT might be an option to treat esophageal cancer if:
You have Barrett’s esophagus and a biopsy has shown abnormal cells called dysplasia. Or your healthcare provider has found the cancer in its very early stages. In these cases, you may have PDT as your only treatment. It may cure the cancer if it hasn’t spread to deeper tissues.
The cancer is considered advanced and the tumor is making it hard to swallow. In these cases, PDT is palliative. This means it eases symptoms but doesn’t cure you. It can help make it easier for you to swallow.
How is photodynamic therapy given?
In most cases, PDT is an outpatient procedure. This means you don’t have to stay in the hospital. A trained nurse or doctor injects you with a light-activated medicine called porfimer sodium. You'll be sent home for 24 to 72 hours while your cells absorb the medicine. The medicine will leave most of your normal cells during this time. But it will stay longer in cancer cells and the cells of your skin.
Then you'll go back to the clinic or hospital for the next phase of treatment. You'll get either local numbing medicine (anesthesia) or general anesthesia, which will make you fall asleep. Then, a healthcare provider will thread a thin and flexible, lighted tube (endoscope) down your throat and into your esophagus. This tube allows your healthcare provider to see inside your esophagus. He or she will direct a special laser light directly at your tumor for several minutes. When the healthcare provider shines the light over the tumor, the medicine absorbs the light and makes a form of oxygen that kills cancer cells. You can normally go home a few hours after you wake up.
You may need to have a cleanup endoscopy several days after PDT. This is done to remove the dead cells. You may also need to have PDT done again.
What are the possible side effects of photodynamic therapy?
Once you receive the medicine, your skin and eyes will become very sensitive to sunlight. It also increases your risk for dangerous sunburns. You need to protect your skin and eyes right away. You should continue to protect your eyes and skin for at least a month to 6 weeks afterward. Your healthcare provider will tell you how to do this.
On the day of your injection, close your shades and curtains at home before you leave.
Bring special clothes with you to the hospital. Wear them after your treatment. These include:
Light colored long-sleeved shirt made out of tightly woven fabric
Light colored long pants made of tightly woven fabric
Wear the protective clothing listed above each day you go outside. You should even wear it on cloudy days. Do not expose your skin to sunlight for the month after treatment.
Don’t go outside during peak sunlight hours, from 10 a.m. to 4 p.m. Limit how often you’re in the sun at other times, even on cloudy days.
Sunscreen alone does not work well enough to protect your skin during this time.
After 30 days are up, ask your healthcare provider if you may expose a small amount of skin on your hand to sunlight for 10 minutes. If you have swelling, redness, or blistering within the next 24 hours, you should continue to protect your skin and eyes from light for another two weeks. If you don't have a reaction, you may slowly increase your exposure to sunlight.
Because the activating light is focused on the tumor, the damage to your surrounding healthy tissue is normally small. Still, you may have burns, swelling, pain, or scarring in nearby healthy tissues, near your windpipe. You may also have these temporary side effects after PDT:
Coughing up blood or mucus
Shortness of breath
Talk with your healthcare provider about how to ease these side effects. Ask about which side effects are serious so you know when to call your healthcare provider.
March 21, 2017
Alteri, Rick, MD,Gersten, Todd, MD