Objective: Interstitial laser therapy (ILT) with the neodymium:yttrium-aluminum-garnet (Nd:YAG) (1064 nm) laser via fiberoptics is becoming a more precise, minimally invasive alternative for thermoablation of unresectable or recurrent head and neck neoplasms, but recurrence is often seen at the margin. Combining intratumor chemotherapy with interstitial laser should be most effective using drugs activated by thermal energy. The objective of the current study was to test intratumor cisplatinum (cis-diaminedichloroplatinum [CDDP]) injections given in conjunction with laser therapy as an experimental approach for improved treatment of squamous cell carcinoma (SCC).
Methods: Human SCC tumors were grown as subcutaneous transplants in nude mice and injected with CDDP (0.4 to 1.2 mg/g) in water or in collagen-based gel carrier with epinephrine (epi-gel) followed by ILT via 0.6-mm fiberoptics coupled to an Nd:YAG laser (1064 nm/180 J).
Results: Tumors injected with CDDP epi-gel exhibited a partial response with two- to fourfold tumor delay compared with aqueous drug or untreated SCC transplants during 10 weeks' follow-up. Combined drug and laser therapy significantly (P < .01) decreased tumor volume, with recurrence in only 25% of animals tested compared with 78% tumor regrowth after ILT alone.
Conclusion: These initial results suggest that laser chemotherapy may become an effective treatment for advanced head and neck cancer.