Advantages of PhotoDynamic Therapy (PDT)

Often cancer is found to be localized and could be treated by surgical removal but for some technical problems. Sometimes, the site is deep inside the body and surgery would constitute a major trauma. Sometimes the site is a vital structure (eg., the upper respiratory bronchi) and cannot be removed surgically. There is a need for a minimally invasive approach toward localized tissue removal.

Light-activated chemotherapy allows selective treatment of localized cancer. The technique is commonly called PhotoDynamic Therapy (PDT). PDT involves administration of a photosensitizing agent to the patient, followed by delivery of light to the cancerous region. The light activates the agent which kills the cancer cells. Without light, the agent is harmless.

Advantage 1: PDT avoids systemic treatment. The treatment occurs only where light is delivered, hence the patient does not undergo needless systemic treatment when treating localized disease. Side-effects are avoided, from losing hair or suffering nausea to more serious complications.

Advantage 2: PDT is selective. The photosensitizing agent will selectively accumulate in cancer cells and not in surrounding normal tissues. Hence, there is selective targeting of the cancer and sparing of surrounding tissues.

Advantage 3: PDT when surgery is not possible. PDT kills cancer cells but does not damage collagenous tissue structures, and normal cells will repopulate these structures. Hence, if a patient has cancer in a structure that cannot be removed surgically (eg., the upper bronchi of the lung), PDT can still treat the site.

Advantage 4: PDT is low cost. PDT is a low-cost minimally invasive localized treatment.

Advantage 5: PDT is repeatable. Unlike radiation therapy, PDT can be used again and again. Hence, it offers a means of long-term management of cancer even if complete cure is not attainable.