Single-wall carbon nanotubes (SWNTs) are a new type of nanomaterial with strong optical absorption. SWNTs also have intense Raman signals that facilitate convenient monitoring of their location within tissue thereby enabling noninvasive pharmacokinetic study. We hypothesize that SWNTs can absorb 785-nm laser light and generate significant local hyperthermia to destroy cancer cells and eradicate tumors. In this study a 785-nm diode laser is used for both Raman excitation and photothermal therapy. SWNTs are made water-soluble by functionalizing with polyethylene glycol (PEG) and administrated by intratumoral injection. C3H/HeN mice were injected subcutaneously with 2 million mouse squamous cell carcinoma (SCCVII) cells to create the tumor model. We conducted experiments with 100 mice divided into 10 different groups: control, SWNT only, 100 mW/cm2 laser irradiation only, 200 mW/cm2 laser irradiation only, and 6 treatment groups with different drug and light dose combinations (SWNTs 0.1, 0.5. 1 mg/ml, laser 100 and 200 mW/cm2). The treatment time was 10 minutes. The temperatures of the tumors irradiated by laser were monitored by an IR thermometer. Mice survival was observed for 45 days. The study revealed that the temperature within the tumors increased in a light- and drug-dose dependent manner. The optimized light and drug dose combinations (1 mg/ml + 120 J/cm2) resulted in tumor temperature elevation of 18.5°C and successful eradication of the tumors. This light dose is moderate and is as low as 1/10 of other published studies using nanomaterials. The Raman spectroscopy measurements suggest that SWNTs persisted within the tumor tissue for months.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.