CALR and neoplasm: Relevant studies showed that PDT could induce immunogenic cell death (ICD) while killing tumor cells to release damage-associated molecular patterns (DAMPs) such as transfer of calreticulin (CRT) from the cytoplasm to the cell surface, secretion of high-mobility group box 1 protein (HMGB1) and adenosine triphosphate (ATP), etc. ICD promotes dendritic cells (DCs) maturation and CTLs activation, proliferation, and differentiation, and ultimately activates the immune system to produce a synergistic effect with ICB therapy [19–22].