PDT, Principles of Treatment

During photoexposure, photons of light transfer their energy to the molecules of the photosensitizer. They, in turn transfer free electrons to oxygen as intermediaries. The oxygen excited in this way begins to enter into chemical reactions with other substances in the cells, in the intercellular substance, and in the blood plasma. As a result of a whole cascade of chemical reactions, the tumor dies. At the same time, healthy tissues remain undamaged, which distinguishes photodynamic therapy (PDT) from radiation therapy, in which radiation damages healthy tissues. For example, after radiation treatment of lip cancer, patients' jaw bone tissue atrophies and teeth fall out, after radiation treatment of skin cancer of the nose, the cartilage of the nose is destroyed and deformed, etc. The cells of the tumor that died during photodynamic therapy are actively absorbed by the cells of the immune system, macrophages and lymphocytes. This serves as a powerful stimulus for the immune system, as a result of which a phenomenon of indirect photodynamic lysis of tumor micrometastases scattered throughout the body is observed in addition to the direct tumor-damaging photodynamic effect. This stage of treatment is called PHOTOINDUCTION OF IMMUNITY.

Photoinduction of immunity is especially pronounced in photodynamic therapy of primary skin melanoma and breast cancer. It is the phenomenon of photoinduction of immunity that can explain the fact that, after PDT of primary melanoma, relapses are not observed at the site of the original tumor, whereas after surgical removal, despite the huge flaps of excised tissue, relapses occur in every 10th patient in the area of the postoperative scar.

Today, PHOTODYNAMIC THERAPY can REPLACE SURGICAL OPERATION and RADIATION TREATMENT for basal cell carcinoma of the skin, squamous cell and metatypical skin cancer, and primary skin melanoma.

Photodynamic therapy can also REPLACE SURGERY and RADIATION TREATMENT for EARLY cancer of the cervix, bladder, tongue, esophagus, stomach, anal canal, larynx, and pharynx, when the tumor affects only the mucous membrane and has not metastasized. Thus, in this category of patients, internal organs can be preserved intact and disability can be avoided. I would like to draw the attention of those of our citizens who want to go to Israel and other countries for treatment. Russia is the most advanced country in terms of photodynamic therapy. Despite the difficulties with funding in the nineties, Professor G.V. Ponomarev at the Orekhovich Institute of Bioorganic Chemistry created a domestic photosensitizer (glucamine salt of chlorin E6), which serves as the basis for many registered drugs for PDT, such as photoditazine and heliofor. Scientists and designers from Moscow and St. Petersburg have created remarkable lasers for photodynamic therapy. Enthusiasts of the method, Professors E.F. Stranadko, M.L. Gelfond, P.B. Popov et al. have developed and actively promoted the introduction of PDT methods for tumors of various localizations. As a result, doctors from Israel, Germany and other European countries come to Russia to get acquainted with photodynamic therapy.

Treatment of cancer by PDT

Recurrence of basal cell skin cancer after radiation therapy on the lip is a complex medical problem. Radiation cannot be used again and oncologists find themselves at a dead end.

Photodynamic therapy according to Dr. Popov's method successfully copes with this situation. However, the result would be much better if basalioma was treated with PDT immediately.

PDT of malignant neoplasms according to Dr. Popov's method is safe and easily tolerated by weakened patients.
➕Even the age of "ninety-nine plus a little more" is not a problem!