Efficacy and toxicity of plasmonic photothermal therapy (PPTT) using gold nanorods (GNRs) against mammary tumors in dogs and cats.

Plasmonic photothermal therapy (PPTT) was introduced as a promising treatment of cancer. This work was conducted to evaluate the cytotoxic effect of intratumoral (IT) injection of 75μg gold nanorods (GNRs)/kg of body weight followed by direct exposure to 2 w/cm2 near infra-red laser light for 10min on ablation of mammary tumor in 10 dogs and 6 cats. Complete blood count (CBC), liver and kidney function were checked before the start of treatment and one month after injection of GNRs. Results showed that 62.5% (10/16), 25% (4/16) and 12.5% (2/16) of treated animals showed complete remission, partial remission and no response, respectively. Tumor was relapsed in 4 cases of initially responding animals (25%). Overall survival rate was extended to 315.5±20.5days. GNRs have no toxic effect on blood profile, liver or kidney functions. In conclusion, GNRs can be safely used for treatment of mammary tumors in dogs and cats.