chloroaluminum-tetrasulfophthalocyanine and Choroid-Neoplasms

To evaluate the effectiveness of photodynamic therapy with chloroaluminum sulfonated phthalocyanine in the treatment of pigmented choroidal melanomas in a rabbit model.. Pigment containing B16F10 murine melanoma cells were implanted transclerally into the subchoroidal space of 28 immunosuppressed New Zealand albino rabbits. The animals were treated with daily injections of cyclosporine and were followed up until tumors at least 2 mm in height were detected by ultrasonography. Twenty-four hours after the intravenous injection of chloroaluminum sulfonated phthalocyanine (CASPc, 5 mg/kg), tumors were irradiated at 675 nm through an argon-pumped dye laser at estimated total light doses of 25 to 70 J/cm2. Control animals were treated with light only or photosensitizer only. The animals were followed up for 4 1/2 to 8 weeks with regular fundus examinations.. Twenty tumor-bearing rabbits were treated with light and dye. The tumor regressed in 12 animals. Five of these animals were followed up for at least 4 1/2 weeks and the other seven for 8 weeks after treatment. At light doses under 40 J/cm2, tumor regrowth was observed in five animals within 10 days of treatment. In all control groups, the tumor-bearing eyes were filled with tumor cells by the third week after implantation. Histologic examination of tumors treated with photosensitizer and light revealed prominent vascular damage early after treatment that resulted in vascular occlusion. Tumor necrosis was evident within 24 hours of treatment.. Results suggest that photodynamic therapy may have a role in the treatment of pigmented choroidal melanomas.

Topics: Aluminum; Animals; Choroid Neoplasms; Female; Indoles; Melanoma; Mice; Mice, Inbred C57BL; Neoplasm Transplantation; Organometallic Compounds; Photochemotherapy; Rabbits; Radiation-Sensitizing Agents; Tumor Cells, Cultured

Although photodynamic therapy has shown great promise for the treatment of a variety of malignant neoplasms, the role of this new therapeutic modality in the clinical management of intraocular tumors remains incompletely understood. This study examines the effects of photodynamic therapy using chloroaluminum sulfonated phthalocyanine on Greene hamster melanoma transplanted into the subchoroidal space in rabbits. Twenty-four hours after intravenous administration of chloroaluminum sulfonated phthalocyanine (5 mg/kg), tumors were irradiated with 675 nm of light at total light doses of 7 to 60 J/cm2. The results show that tumor growth was arrested at total light doses of 22 to 60 J/cm2. At total light doses of 15 to 21 J/cm2, tumor growth was initially arrested. However, regrowth of these tumors was apparent within 7 days. Total light doses of less than 15 J/cm2 showed no response. Complications of photodynamic therapy, such as intraretinal or subretinal hemorrhages and retinal detachment, were seen only in animals who received total light doses in excess of 43 J/cm2.

Topics: Aluminum; Animals; Choroid Neoplasms; Corneal Edema; Disease Models, Animal; Fluorescein Angiography; Fundus Oculi; Indoles; Light; Male; Melanoma, Experimental; Neoplasm Transplantation; Organometallic Compounds; Photochemotherapy; Rabbits; Radiation-Sensitizing Agents; Retinal Diseases