Photodynamic treatment (PDT), a new approach, uses photosensitizers that release reactive oxygen species (ROS) when they are triggered by near-infrared (NIR) light. This minimally invasive technique reduces off-target toxicity while allowing for the targeted destruction of cancerous tissues. Deep-tissue penetration, tumor selectivity, and photosensitizer stability have all improved with recent developments in nanotechnology. Furthermore, PDT-induced immunogenic cell death (ICD) improves systemic anticancer immunity and may work in concert with chemotherapy and immunotherapy. AI-driven treatment planning and advancements in light delivery, such as activation mediated by X-rays and ultrasounds, are increasing the therapeutic uses of photodynamic therapy. With the aim of improving treatment efficacy, NIR-mediated photodynamic therapy (PDT) combines photophysics, nanomedicine, and immunotherapy.