Photodynamic Therapy (PDT)
Short Introduction Photodynamic therapy (PDT) 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 in treating many kinds of tumors. • The cure rate is high as 90% for some early cancer (esophageal and lung cancer). For advanced cancer, more 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- pharyngeal tumor Early oral, nosal and nasopharyngeal 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 eradicate neoplasm in cavity Barrett esophagus PDT can effectively eradicate Barrett epithelium and early adenocarcinoma. Lung cancer • For lung cancer with bronchial obstruction, PDT induced improvement for air-way obstructions • For early bronchial cancer, PDT has a cure rate of 90%; for obstructive cancer, the improvement rate is 85%.Gastric cancer • PDT can eradicate cancer for up to 80% of early 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 cancer cases experience improvement after PDT.Other cancers 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). >> Contact Us for free consultation Need Help? Contact Us Detailed Explanation Photodynamic therapy (PDT), as a scientific, appropriate, noninvasive therapy, will usher in a new age in tumor therapy, just as penicillin helped to revolutionize pneumonia treatments in the 1930s. PRINCIPLE PDT is a non-thermal light chemical reaction and requires oxygen, photosensitive substance (photo-sensitizer) and laser simultaneously. The photo-sensitizer is absorbed by neoplasm tissue and accumulates in the cells for a long time. The photo-sensitizer is activated with the appropriate wavelength of light and reacts with oxygen to generate reactive single state oxygen and a hotochemical substance that are toxic to cells. This leads to apoptosis and necrosis of cancer; PDT can result in local vascular lesion of tumor. PDT can make tumor tissue ischemic necrosis and initiate immune reaction of antitumor. PROCEDURE • Photosensitizer (Photofrin, porfimer sodium), 2mg/kg,is administrated intravenously 48 hours before scheduled light activation. • Laser light irritation: 48 hours after photosensitizer administration, 630-nm red laser light is delivered through optic cables (thin fibers that transmit light) to deliver light to areas inside the body. The light used for PDT can come from a laser or other sources of light. The total light dose administered ranges from 20 to 30 J/cm2. The light irritation is often repeated 72 hours after photo-sensitizer administration. >> Contact Us for free consultation.Need Help? Contact Us • The delivery of laser fiber may be through endoscopes, such as gastrointestinal endoscope (for esophageal or gastric cancer) or bronchendoscope (for lung cancer), or it may be delivered intraoperatively. • PDT may also be repeated and may be used with other therapies, such as surgery, radiation, or chemotherapy. INDICATION Formally Approved America • Esophageal cancer (via particles or completely obstructive) • Redical treatment of early stage esophageal cancer • Microinvasive non-small cell lung cancer, unable to be given surgery and radiotherapy • Obstructing, non-small cell lung cancer Europe • Esophageal cancer and lung cancer • Radical treatment of early stage lung cancer Japan • Early stage of lung cancer • Superficial esophageal cancer • Superficial gastric cancer • Early cervical cancer and metaplastic proliferation Canada • Obstructing esophageal cancer, unable to be given Nd:YAG laser therapy • Early non-small cell lung cancer Good effects shown by study Barrett~s esophagus with high-degree displasia and esophageal adenocarcinoma Effective report from clinicsEarly stage of carcinoma of oral cavity, tumor of head-neck, brain tumor, pleural or peritoneal mesothelioma, sarcoma in abdominal cavity, eye tumor, asophary geal cancer, tumor of chest wall, breast cancer, gynecologic cancer, rectal cancer, Kaposi sarcoma, skin cancer Good prospects of applicationBone marrow, rheumatoid arthrositis, arteriolosclerosis, prevention of restricture after vascular plasticity, macula degeneration, streptococcus infection in peridentium, helicobacter pylori, wound infection. Need Help? Contact Us>> Contact Us for free consultation. Advantages • Relative selectivity and tissue specificity for tumor cells; • Low toxicity, good safety, no immuno-suppression and marrow inhibition; • No harmful effects on other therapies, complementary to surgery, radiotherapy and chemotherapy; • Short treatment time; • Initiating therapeutic effect within 48-72 hours; CLINICAL APPLICATION Oral- pharygeal tumor For early oral, nosal and nasopharygeal cancer: PDT had effective rates of 75%-100%. Esophageal cancer • PDT had radical effect for early esophageal cancer; • PDT brings the five-year survival rate of 74%-84% in T1 and T2 stage of esophageal squamous and adenocarcinoma; 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 intracavity and a stent has been placed, PDT can eradicate neoplasm in cavity. >> Contact Us for free consultation.Need Help? Contact Us Barrett esophagus Normal squamous epithelium lining the esophagus is replaced by glandular columanar epithelium, a process known as called Barrett esophagus, which increases the risk of esophageal adenocarcinoma. PDT not only can effectively eradicate Barrett epithelium, but it also has good results for early adenocarcinoma. Lung cancer • For lung cancer with bronchial obtruction, PDT induce improvement of air- way obstruction • Treatment of lung cancer with PDT was approved by the USA~s FDA • For early bronchial cancer, PDT has the cure rate of 90%; for obstructive cancer, the improvement rate is 85 percent. Gastric cancer • PDT can eradicate cancer for 80% of early gastric cancer • PDT
Photodynamic Therapy (PDT) Read More »
