Cancer

Photodynamic therapy (PDT) is a special procedure for cancer which combines a drug (called a photosensitizer or photosensitizing agent) with a specific type of light to kill cancer cells Advantages

• Relatively selective and specific for tumorous cells
• Effective many kinds of tumors.
• The cure rate is high as 90% for some early cancer (esophageal and lung cancer). For advanced cancer, itmore than 70% of patients experience improvement.
• No toxicity, no immunosuppression, or bone marrow suppression
• No negative effect when combined with other therapies (chemo/radiotherapies); instead, they have a complementary effect.
• Short treatment time and efficacy occurs within 48-72 hours

Clinical use Oral- pharygeal tumor Early oral, nosal and nasopharygeal cancer: PDT had effective rates of 75%-100%.
Esophageal cancer

• PDT had radical effect for early esophageal cancer
• PDT can effectively ameliorate obstruction of advanced esophageal carcinoma
• Very effective for cervical esophageal cancer
• Able to treat undermucosal disseminated and latent cancer
• For cancer which grows into intracavity and stent has been placed, PDT can eradicateneoplasm in cavity

Barrett esophagus PDT not only can effectively eradicate Barrett epithelium, but also has shown good result for early adenocarcinoma. Lung cancer

• For lung cancer with bronchial obstruction, PDT induced improvement for air-way obstructions
• For early bronchial cancer, PDT has the cure rate of 90%; for obstructive cancer, the improvement rate of 85%.

Gastric cancer

• PDT can eradicate cancer for up to 80% ofearly gastric cancer
• PDT can improve symptoms of advanced gastric cancer

Bladder cancer Cancer in situ can be eradicated by PDT. Seventy-one percent of advanced cases experience improvement after PDT. Other cancer for which PDT is effective:

Colon-rectal carcinoma, cholangiocarcinoma (especially bile duct cancer in hepatic hilum,,pancreatic carcinoma and cancer of Vater's ampulla, tumor in abdominal cavity, pleural and peritoneal mesothelioma, liver cancer, brain tumor tumors of the genitourinary tract skin and subcutaneous tumor

It is considered by specialists that photodynamic therapy (PDT), as a scientific, appropriate, noninvasive or micro-invasive therapy which developed at the beginning of the 21st century, will open the new epoch in tumor therapy in future, just as penicillin invented in 1930s made death rate of infectious diseases such as pneumonia decrease dramatically.