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Over the past decade, there have been increasing applications for laser technology in the treatment of patients with gynecologic diseases. Following the early reports about the applications of carbon dioxide laser technology, other investigators have evaluated Nd-YAG laser devices and, most recently, Argon lasers for treatment of gynecologic lesions. As the continued growth and interest of applications of lasers in gynecology has proceeded, the question as to whether there is a role for lasers in the treatment of invasive gynecologic malignancies has arisen. It is as yet unanswered because of limited experience with laser applications in gynecologic cancer. Carbon dioxide lasers have been primarily used to treat precancerous lesions. Nd-YAG and Argon technology for other types of malignant neoplasms have been reported. An understanding of the biology of gynecologic cancer is important to facilitate future applications for CO2, Nd-YAG, and Argon laser energies. Finally, photoradiation therapy, which combines drug treatment with subsequent laser irradiation, represents the newest application of lasers- in the treatment of gynecologic neoplasia.Over the past decade, there have been increasing applications for laser technology in the treatment of patients with gynecologic diseases. Following the early reports about the applications of carbon dioxide laser technology, other investigators have evaluated Nd-YAG laser devices and, most recently, Argon lasers for treatment of gynecologic lesions. As the continued growth and interest of applications of lasers in gynecology has proceeded, the question as to whether there is a role for lasers in the treatment of invasive gynecologic malignancies has arisen. It is as yet unanswered because of limited experience with laser applications in gynecologic cancer. Carbon dioxide lasers have been primarily used to treat precancerous lesions. Nd-YAG and Argon technology for other types of malignant neoplasms have been reported. An understanding of the biology of gynecologic cancer is important to facilitate future applications for CO2, Nd-YAG, and Argon laser energies. Finally, photoradiation therapy, which combin...

The uptake, distribution, and retention of hematopophyrin derivative (HPD) in the rat 9L gliosarcoma brain tumor model has been evaluated using a digitized video fluorescence technique. In addition, histopathologic examination, and survival studies have been used to assess the in vivo cytotoxic effects of photoradiation therapy (PRT) in this model.The uptake, distribution, and retention of hematopophyrin derivative (HPD) in the rat 9L gliosarcoma brain tumor model has been evaluated using a digitized video fluorescence technique. In addition, histopathologic examination, and survival studies have been used to assess the in vivo cytotoxic effects of photoradiation therapy (PRT) in this model.

Photodynamic Therapy (photoradiation Therapy or PRT, Phototherapy) or PDT is a well documented new modality in cancer therapy. It had its beginnings around the turn of the century but was soon discarded as a medical therapeutic tool. Dr. Thomas Dougherty, a chemist at Roswell Park Memorial Institute in Buffalo, New York, resumed interest in this as a cancer therapy in the early 1970’s. He and his staff worked out the mode of action of this photochemical reaction and successfully applied it to treat solitary tumor masses.Photodynamic Therapy (photoradiation Therapy or PRT, Phototherapy) or PDT is a well documented new modality in cancer therapy. It had its beginnings around the turn of the century but was soon discarded as a medical therapeutic tool. Dr. Thomas Dougherty, a chemist at Roswell Park Memorial Institute in Buffalo, New York, resumed interest in this as a cancer therapy in the early 1970’s. He and his staff worked out the mode of action of this photochemical reaction and successfully applied it to treat solitary tumor masses.

A program of photoradiation therapy (PRT) of cancer employing the sensitizing agent Hematoporphyrin Derivative (HPD) was begun at UC, Irvine in May, 1981. We have used light obtained from a laser source to initiate the photochemical reaction required for tumor destruction. Initially a four-watt argon laser was used to pump a tunable dye laser emitting light at 630 nm. The system has been upgraded by adding a 12-watt argon laser (Spectra-Physics, Mt. View, CA).

Photoradiation therapy (PRT) is the treatment of tumors by a combination of visible light and a photosensitizing drug, usually hematoporphyrin-derivative (HpD). This drug is photodynamically active, fluorescent, and attains a higher concentration in malignant tumor than in most normal tissues after intravenous injection. The light source is usually an argon-laser pumped dye laser with an output of about 800 milliwatts at 630 nm. A system for prediction and control of the effective absorbed dose is being developed based on calculations and measurements of the space irradiance of the light as it diffuses through tissue, the concentration of HpD derived from fluorescence measurements, the optical characteristics of tissues, and the absorption of light in HpD and transfer of part of the quantum energy to molecular oxygen, generating the cytotoxic singlet oxygen.Photoradiation therapy (PRT) is the treatment of tumors by a combination of visible light and a photosensitizing drug, usually hematoporphyrin-derivative (HpD). This drug is photodynamically active, fluorescent, and attains a higher concentration in malignant tumor than in most normal tissues after intravenous injection. The light source is usually an argon-laser pumped dye laser with an output of about 800 milliwatts at 630 nm. A system for prediction and control of the effective absorbed dose is being developed based on calculations and measurements of the space irradiance of the light as it diffuses through tissue, the concentration of HpD derived from fluorescence measurements, the optical characteristics of tissues, and the absorption of light in HpD and transfer of part of the quantum energy to molecular oxygen, generating the cytotoxic singlet oxygen.

The use of arrays of light-emitting diodes (LEDs) is proposed for hematoporphrin-besed therapy of tumor cells. Such arrays can be assembled from unencapsulated, commercially available, LED chips to provide power densities sufficient for therapy. Advantages over other sources include efficiency, simplicity, size and eventual low cost.The use of arrays of light-emitting diodes (LEDs) is proposed for hematoporphrin-besed therapy of tumor cells. Such arrays can be assembled from unencapsulated, commercially available, LED chips to provide power densities sufficient for therapy. Advantages over other sources include efficiency, simplicity, size and eventual low cost.

Clinical laser treatment of neoplastic conditions in urology have emphasized the use of the CO2 and Nd-YAG lasers. The Argon laser has limited use because of its lower power density. Photoradiation therapy with hematoporphyrin derivative is investigational. Exciting prospects exist with the advent of CO2 fiber technology.Clinical laser treatment of neoplastic conditions in urology have emphasized the use of the CO2 and Nd-YAG lasers. The Argon laser has limited use because of its lower power density. Photoradiation therapy with hematoporphyrin derivative is investigational. Exciting prospects exist with the advent of CO2 fiber technology.