Measuring system based on the binocular microscope for analysis of intracellular accumulation of infrared IR photosenstizers allowing to obtain graphic data about state of analyzed objects, location of fluorescence foci and to obtain details of spectral profile of fluorescence emission centers in IR spectral region was developed. According to image of fluorescence signal distribution the location of photosensitizer accumulation in the cell may be detected accurately and the spectrum of fluorescence signal of near IR-range in the targeted point may be obtained. The developed system is quite comprehensive because there is an opportunity to choose technical parameters, operating modes, measuring methods and analysis. The advantage of the developed microscope-spectrum analyzer is an opportunity to focus emission and create high power intensity on the irradiated area by means of laser source with small-angle beam spreading, all this allow to perform ultra-precise operations with cells. Particularly, tunable size of the diaphragm opening in the far field allows to register fluorescence signal on certain cell organoids. By means of developed system the studies of accumulation of the new bacteriochlorine photosensitizers on HeLa cell line were performed. The system allowed to register accumulation of cancer cells with definite sites of selectively accumulated photosensitizer. The sites of fluorescence were the centers of accumulation of bacteriochlorine photosensitizer, this suggests that studied photosensitizer has a tendency for local accumulation in cellular organoids. The authors suggested that the developed system allowed to perform the effective and rapid screening of new photosensitizers, particularly IR bacteriochlorine photosensitizers.

The impact of irregularity in radionuclide coating of scaffold on the distribution of absorbed dose produced by grid of microsources was analyzed. On engineering software MATHCAD the program for calculation of absorbed dose produced by grid of microsources was created. To verify this algorithm the calculation model for MCNP code was established and represented the area consisted of soft biological tissue or any other tissue in which the grid of microsources was incorporated. Using the developed system the value of possible systematic irregular coating of radioactivity on the microsource’s core was analyzed. The distribution of activity along the surface of microsource was simulated to create distribution of absorbed dose rate corresponding to experimental data on radiation injury. The obtained model of microsource with irregular distribution of activity was compared to conventional microsource with core coated regularly along the entire area of the silver stem by main dosimetry characteristics. The results showed that even for extremely irregular distribution of activity the distribution of dose rate produced by microsource in the tumor area was not substantially different from dose-rate field obtained for microsource with regularly coated activity. The differences in dose rates (up to 10%) in areas which were the nearest to the center of the grid were significantly lower than its decline from center to periphery of the grid. For spatial distribution of absorbed dose for specific configuration of microsource set and tracing of curves of equal level by selected cut-off the program SEEDPLAN was developed. The developed program represents precisely enough the spatial distribution of selected configuration set of microsources using results of calculation data for absorbed dose around the single microsource as basic data and may be used for optimal planning of brachytherapy with microsources.

The results of evaluation of the efficiency of photodynamic therapy with photosensitizer radachlorine for basal cell carcinoma are represented. The study included patients with primary and recurrent cancer, solitary and multiple foci of different histological subtypes. All tumors corresponded stages T1-2N0M0. The radachlorine solution was injected into pathological focus at dose of 1.75-3.50 mg/ cm2 of tumor 15 min before the onset of irradiation (wavelength of 662 nm, light dose of 300 J/cm2). The evaluation of efficiency by means of short-term and long-term outcomes was performed on the basis of clinical and cytological data. According to shortterm outcomes evaluation, the total tumor regression was in 43 (95,5%) patients for 47 (95,9%) tumors. The partial regression was achieved in 2 (4,5%) patients, who subsequently had one repeated course of photodynamic therapy with short-term outcome as total tumor regression. All patients with multiple, superficial and nodal forms of basal cell carcinoma had total tumor regression in 100% of cases, with ulcerated form – in 94,4%, with morphea-like form – in 83,3%. During follow-up in subjects, 44 (97,7%) patients had 5-year recurrence-free period. The relapse of tumor was detected in 1 (2,3%) patient after PDT for primary cancer of nasal ala stage Т2N0M0 of solid and adenoid histological subtype. Thus, photodynamic therapy with intralesional injection of radachlorine showed high efficiency for treating all existent clinical forms and histological subtypes of basal cell carcinoma.

The main challenge of treating non-muscle invasive bladder cancer is multifocal tumors. Current methods of diagnosis are failed to detect all superficial flat tumor lesions in bladder mucosa. The use of fluorescence imaging with 5-aminolevulinic acid (5-ALA) allows to improve the sensibility of routine cystoscopy, but low specificity decreases its diagnostic accuracy. The method of fluorescence imaging combined with local fluorescence spectroscopy developed in P.A. Herzen MCRI has been shown to increase the specificity from 71% to 84%. Thus, local fluorescence spectroscopy in visible fluorescence of 5-ALA-induced protoporphyrin allows to perform guided biopsy and decrease the rate of diagnostic mistakes.

The results of clinical study for efficacy of photodynamic therapy (PDT) with radachlorine in patients with pre-cancer and cancer of cervix are represented. The study enrolled 30 patients including 4 patients with cervical erosion, 5 patients with cervical intraepithelial neoplasia II, 13 patients with cervical intraepithelial neoplasia III, 4 patients with carcinoma in situ and 4 patients with cervical cancer stage Ia. Radachlorine was administrated as single 30 minute intravenous injection at dose of 1,0 mg/kg of body weight 3 h before irradiation (wavelength of 662 nm, light dose of 300–350 J/cm2). The results of treatment in 26 (86,7%) patients was assessed as complete tumor regression and in 4 (13,3%) patients — as partial regression. In cervical erosion, intraepithelial neoplasia II and carcinoma in situ groups total regression was in all cases. In the cervical intraepithelial neoplasia III group total regression after first course of PDT was achieved in 77% of patients, in cervical cancer stage Ia group – in 75% of patients. From 3 to 6 months after first course of treatment all patients with partial tumor regression underwent the second course of PDT with complete regression. There were no side-effects due to radachorine or PDT in the course of treatment and during follow-up. Thus, PDT with Russian photosensitizer radachlorine showed high efficiency for treatment of pre-cancer and cancer of cervix.

Results of clinical follow-up of the patient with squamous cell skin carcinoma of the nasal dorsum are represented. The patient underwent a course of combined photodynamic therapy (PDT) with distant gamma-ray therapy. Distant gamma-ray therapy was performed daily during 12 days (single dose of 3 Gy, total dose of 36 Gy) with the first session 24 h after injection of the photosensitization. For PDT the photosensitizer photosens at dose of 0,3 mg/kg was used. The method of prolonged PDT was applied, sessions of laser irradiation were performed daily during 7 days. The PDT sessions were carried out 2 h after session of gamma-ray therapy using distant (150 J/cm², 40 mW/cm²) and contact (500 J/cm², 100 mW/cm²) modalities. According to multiple cytological studies after treatment there were no signs of tumor, but inflammation. Four months after treatment according to cytological data continued tumor growth was detected. The patient underwent an additional course of PDT. Currently the patient is under follow-up: no recurrence during 8 months after repeated treatment.