Advancements and emerging trends in photodynamic therapy: innovations in cancer treatment and beyond

Photodynamic therapy (PDT) has emerged as a sophisticated, non-invasive therapeutic approach for treating various malignancies and non-oncological conditions. This review examines the fundamental principles and recent advances in PDT oncological applications. PDT's mechanism relies on the selective accumulation of photosensitizers (Ps) in pathological tissues followed by localized activation via specific wavelengths of light, generating cytotoxic species that induce tumor cell death while sparing adjacent healthy tissues. Despite its proven efficacy, conventional PDT faces limitations, including suboptimal Ps delivery, insufficient tissue penetration, and potential side effects. Recent breakthroughs in nanotechnology have created unprecedented opportunities to overcome these challenges through engineered nanocarriers that improve photosensitizer pharmacokinetics, biodistribution, and target specificity. This review explores multifunctional nanoformulations combining PDT with complementary therapeutic modalities such as photothermal therapy and chemotherapy. The review also addresses emerging trends in clinical translation, highlighting recent trials that demonstrate promising outcomes across multiple cancer types. We conclude by identifying remaining challenges and future directions for optimizing enhanced PDT as a precision anticancer strategy with the potential to impact standard treatment protocols for various malignancies significantly.