LASER TREATMENT OF EXPERIMENTAL MALIGNANT TUMOURS

Abstract

Some of the results of experiments performed during the past 2 years to assess effects of laser energy on experimental malignant tumors are reviewed. Twenty types of malignant tumors (most in the cheek pouch and 11 of human origin) were treated in over 700 Syrian hamsters. Results of laser treatment of malignant melanomas and thyroidal carcinomas are presented. A human patient with malignant melanoma treated by laser energy is described. Investigation of thermal effect revealed that the laser-treated tumor remained warm for about one minute, while the cautery-treated tumor cooled to normal temperature in 5 seconds. Direct action of laser on superficial tumors is possible; deeper lesions must be exposed surgically. Laser energy has a selective effect on certain malignant tumors, resulting in their progressive regression, and ultimate dissolution. All hamsters with implanted malignant melanomas and carcinomas of human origin, after completion of a course of laser treatment, showed no gross or histologic evidence of tumor up to the date of last observation.