Photodynamic diagnostics and therapy of tumors with сombined use of 5‐aminolevulinic acid and chlorin e6

Tumor heterogeneity significantly affects the accumulation and distribution of PS in tissues, including different areas of the same tumor, affecting the effectiveness of PDD and PDT. For PDD and PDT of patients with head and neck tumors, two PSs were administered in combination: 5-ALA and Ce6. PDT was performed using 635 nm and 660 nm lasers. 5-ALA-induced PpIX and Ce6 accumulation were assessed using fluorescence diagnostic methods. With the combined administration of 5-ALA and Ce6, different accumulations of 5-ALA-induced PpIX and Ce6 were observed in the central and border areas of the tumor. Complete therapeutic pathomorphosis of the tumors was obtained after one to two PDT sessions. Combined use of Ce6 and 5-ALA, with their different mechanisms of PDT action, opens new possibilities for relapse-free tumor treatment.