The physicochemical and photophysical properties, as well as photo-induced activity, of glycoconjugates based on chlorine е₆ trimethyl ether with various positions of carbohydrate fragment in the macrocycle have been studied. The photo-induced activity was investigated in the human (HEp2, A549 and HT29) and animal (LLC) cell lines. The tested compounds showed in vitro both high photo-induced activity and high stability in the dark. The photosensitizer with galactose in the A pirrole ring demonstrated the highest activity (the half maximal inhibitory concentration (ИК₅₀) varied from 27±2 nM to 75±5 nM in tests on different cell lines). Dyes with sugar substitutes in the C pirrole ring were 5–10 times less active.

 

Results of the study for anticancer efficacy of photodynamic therapy with chlorin e6 dimethyl ether for treatment of outbread rats with sarcoma M-1 are represented. The drug was given intravenously or intraperitonealy at a dose of 1.25 mg/kg body weight (light dose – 300 J/cm²) or 2,5 mg/kg body weight (light dose – 150 J/cm²). The spectrometry showed that maximal drug accumulation in tumor was in 2 h after intravenous injection or 3 h after intraperitoneal injection of photosensitizer, thus, sensitized tumors were irradiated according to these time intervals. Intraperitoneal injection of chlorin е₆ dimethyl ether at a dose of 1.25 mg/kg body weight with treatment session in 3 h and light dose of 300 J/cm² was the most effective (the complete response in animals – 86%).

The experience of treatment for precancer and early cervical cancer by photodynamic therapy in 12 patients with primary diagnosis H-SIL (CIN II–III) and cancer in situ is described. Chlo-rine photosensitizer Photolon was given intravenously at a dose of 0.75–1.15 mg/kg body weight. 2.5 h later the treatment with polyposition laser exposure (light dose – 150 J/cm², light power density – 400–500 mW/cm²) was made. Thirty days later conization of the cervix with endocervical curettage assessing therapeutic response of cervical tumor tissue was per-formed. According to histological data complete response was in 4 patients, minute foci of CIN I were determined in 7 patients, 1 patient had foci of CIN II. 8 of 10 HPV-positive patients had complete eradication of HPV after treatment. There were no serious adverse events after light exposure. Marked therapeutic response, high anti-viral activity and good feasibility allow to consider photodynamic therapy as alternative organ-sparing treatment of early cancer and pre-cancer of cervix.

 

Results of treatment for cutaneous metastasis of breast cancer with photjdynamic therapy are represented. The study included 46 patients, the total number of treated cutaneous metastases was 535. For photodynamic therapy photosensitizer photolon given intravenously at a dose of 0.9–1.6 mg/kg body weight 3 h before treatment session (wave length 661±1 nm, плотность мощности 0,11–0,56 J/cm²), мощность на выходе волокна 0,3–2,0 Wt, light dose 50–600 J/cm². Complete regression of metastasis was obtained in 33.6% of cases, partial – in 39.4%, stabilization – in 22.6%, progression of disease was in 4.3% of cases. The results show the perspectiveness of photodynamic therapy for metastasis as one of the step of treatment.

 

The article reviews mechanisms of sonodynamic therapy with photosensitizers (ultrasound + photosensitizer) and combination of sonodynamic with photodynamic therapy (ultrasound + photosensitizer + light exposure) for treatment of malignant tumors. Efficacy of these methods with photosensitizers of different chemical structure in experimental study in vitro and in vivo on different tumor models and in clinical trials was assessed.

 

The case of successful intraoperative fluorescence diagnosis (IOFD) for removal of cervical and thoracic ependymoma performed in P.A. Herzen MCRI is reported. For FD we used the Alasens (Research Institute of Organic Semi-Finished Products and Dyes). The drug solution was given per os at a dose of 20 mg/kg body weight 2.5 h before surgery. IOFD was per-formed 3 h after intake of photosensitizer. For fluorescence diagnosis there was average in-tensity of fluorescence in tumor and no fluorescence in normal spinal tissues. The extent of surgery was determined according to results of IOFD. The control MRI of cervical and supeior thoracic spine with contrast enhancement and follow-up confirmed definitive removal of tumor and showed no postoperative complications.

The case of successful photodynamic therapy in patient with erythroplasia of Queyrat is re-ported. The treatment was performed under spinal anesthesia after local application of alasens gel. The exposition of the drug was 5 h with light dose – 150 J/cm². There were no complications in the post-treatment period. The complete tumor regression was noticed 3 months after treatment. The follow-up period accounted for 1.5 years. Thus, photodynamic therapy is efficient in terms of organ-preserving treatment in patients with penile cancer.

 

The technique of intraoperative fluorescence diagnosis with alasens for brain metastases includes visual assessment of alasens-induced protoporphyrin IX fluorescence and local spectroscopy. The technique allows to reduce the rate of misdiagnosis, to assess accurate local extent of brain metastases and to improve surgical radicality. When applying this technique the sensitivity of fluorescence diagnosis is 96.7%, the specificity is 100%. The technique is designed for neurosurgeons specialized on neurooncology.