Photodynamic therapy in the treatment of recurrent nasal cavity and paranasal sinus cancer

The purpose of the study was to evaluate the effectiveness of treatment of patients with recurrent nasal cavity and paranasal sinus cancer using photodynamic diagnosis (PDD) and photodynamic therapy (FDT). Material and Methods . The study included 40 patients with locally advanced nasal cavity and paranasal sinus cancer, who were admitted to the clinics of the Cancer Research Institute of Tomsk National Research Medical Center with disease progression or recurrence. All patients were divided into the study group (n=20) and the control group (n=20). Patients in both groups received chemotherapy combined with radiotherapy, chemotherapy combined with surgery or a combination of chemotherapy, radiotherapy and surgery. Treatment of patients included intraoperative assessment of resection margin using a laser electron spectral analyzer LESA-01 BIOSPEC. The bed of the removed tumor was examined to detect residual tumor tissues. Photodynamic therapy of the bed of the removed tumor was then performed using Photoditazine at a dose of 1 mg/kg body weight. Radiotherapy at a dose of 300–350 J per feld was given using a Latus–T apparatus, the feld diameter ranged from 1 to 2 cm. The power density varied from 0.4 W/cm2 to 0.5 W/cm 2 . Results . Nonparametric tests revealed a statistically signifcant difference in disease-free survival: 3.10, p=0.001 by Gehan-Wilcoxon test and 3.03, p=0,002 by Log-Rank test. When assessing overall survival, there were 10 (50.0 %) completed cases in the control group, 4 (20.0 %) in the study group, and 10 (50.0 %) and 16 (80.0 %) censored cases, respectively. Gehan-Wilcoxon test – -2.02 p=0.04. Log-Rank test –2.10 p=0.04. The results of the study showed that according to any of the criteria, there were statistically signifcant differences in survival between the control and study groups. Conclusion . Inclusion of intraoperative PDD and PDT in the treatment algorithm for nasal cavity and paranasal sinus recurrent carcinomas signifcantly increases the disease-free and overall survival of patients.