Photothermal Therapy: From Encouraging Lab Results to Lackluster Clinical Translation

Cancer is a pervasive and complex disease that poses a significant threat to public health worldwide. The prevalent therapeutic options, including chemotherapy and radiotherapy, pose detrimental side effects. Consequently, non-invasive and selective therapeutic strategies are sought, such as nanoparticle-mediated photothermal therapy (PTT). This technique employs benign photothermal agents that gather within tumors post-injection. Under near-infra-red light exposure, these agents induce localized hyperthermia, killing tumor cells. Here, the laboratory development, recent advances, and clinical status of photothermal therapy are examined. Despite two decades of development, photothermal therapy has yielded few clinical trials. A standout agent, the gold nanoshell, holds promise for prostate cancer treatment as the only one in human clinical trials. To provide context, PTT is compared to photodynamic therapy, which has over 250 human trials in 40 years, highlighting the need to bridge the gap for effective photothermal therapy translation. Therefore, we delve into the gap of clinical implementation between photothermal therapy and similar technologies, such as photodynamic therapy, laser interstitial thermal therapy, and cancer nanomedicines, offering insights and potential solutions.