Combined intratumor cisplatinum injection and Nd : YAG laser therapy

Objectives/Hypothesis: Interstitial laser therapy (ILT) has become useful f or tumor palliation in patients with advanced head and neck cancer Cisplati num chemotherapy also is a frequent adjuvant treatment for recurrent tumors , but systemic toxicity limits application. Intratumor cisplatinum injectio n combined with ILT may improve therapy of these recurrent tumors with redu ced toxicity. Study Design: Prospective. Tumor transplants were injected wi th cisplatinum in a gel implant before ILT to evaluate treatment response a nd toxicity in a preclinical study. Methods: UCLA-P3 human squamous cell ca rcinoma tumors were grown as subcutaneous transplants in nude mice and trea ted by intratumor injection of 2 mg/mL cisplatinum in a slow-release, colla gen-based gel carrier 4 hours before interstitial implantation of Nd:YAG la ser fiberoptics to induce local tumor hyperthermia. Treatment efficacy and toxicity were followed for 12 weeks after combined drug and laser therapy c ompared with ILT alone, Results: Combined cisplatinum gel and ILT was a sig nificant improvement (P <.01 by chi-square test) and induced 57% complete r esponses without regrowth in 21 transplanted tumors compared with only 24% in 21 tumors after ILT alone during 12-week follow up. Recurrences in both cases appeared to result from nonuniform laser energy delivery within tumor s via the implanted fiberoptic tip, Conclusions: The results of this experi mental combined cisplatinum and ILT study suggest it may be possible to imp rove treatment of advanced head and neck cancer by intratumor injection of gel implants containing the drug followed by interstitial Nd:YAG laser hype rthermia.