LASER PHOTOCHEMOTHERAPY - A LESS INVASIVE APPROACH FOR TREATMENT OF CANCER

The effectiveness of combining surgery with chemo- and radiation thera py in treatment of human cancer provides a useful model for further de velopment of new multimodality approaches including laser photochemoth erapy. Laser endoscopy often is a useful treatment for obstructive tum ors in airways, but interstitial laser fiberoptics is becoming a more precise, minimally invasive alternative for ablation of unresectable o r recurrent neoplasms. Combining intratumor chemotherapy with laser en ergy delivery via interstitial fiberoptics should be most effective us ing drugs activated by photothermal energy. A number of investigators have shown that anthracyclines and cis-platinum are likely candidates for light or heat activation in cancer cells. An advantage of anthracy clines is their dual role as antitumor drugs and as photosensitizers. Because they are effective chemotherapy agents without photoactivation , two approaches are possible to increase tumor responses. Maximum tol erated dose followed by photoillumination via laser fiberoptics can be used to obtain better tumor palliation. Improved treatment response t o lower intratumor drug levels after laser activation also should redu ce systemic toxicity. Preclinical studies and recent case reports from several groups suggest photochemotherapy with currently approved drug s and lasers may soon become an attractive alternative for treatment o f recurrent tumors in cancer patients. (C) 1995 Wiley-Liss, Inc.