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The study of the functional morphology of rat sarcoma M-1 after photodynamic therapy using bacteriopurpurinimide disulfide derivative (disulfide-BPI) as a photosensitizer is described. The research methods included immunohistochemistry for PCNA and CD31, evaluation of mitotic activity and apoptosis of tumor cells, as well as computer analysis of microscopic images. Photoinduced antitumor effect was shown to be due to the destruction of sarcoma M-1 vascular bed, the rapid inhibition of proliferative activity and devitalization of tumor cells by apoptosis and necrosis. It is reasonable to suppose that in the early stages after photodynamic therapy destruction of the microvasculature and photocytostatic shock of tumor cells with subsequent development of necrosis are caused by direct influence of the light flux on sensitized cellular elements in parenchyma and stroma of tumors. The efficiency of photodynamic therapy with the novel photosensitizer is determined by the sequence of destructive and inflammatory changes in tumor parenchyma and surrounding tissues, as well as repopulation potential of tumor cells survived after treatment.

The results of a study on the effectiveness of photodynamic therapy with a photosensitizer fotoditazin and cryotherapy for actinic keratosis are represented in the article. The study included 80 patients with 215 lesions, among them erythematous form of actinic keratosis was diagnosed in 151 (70.2%) cases, hyperkeratotic form – in 46 (21.4%) cases, a pigmented form – in 12 (5.6%) and an atypical variant of the disease – in 6 (2.8%) cases. According to histological type the distribution of tumor was as follows: 19 (54.3%) cases were diagnosed as hypertrophic type, 6 (17.1%) – atrophic, 8 (22.9%) – bowenoid and 2 (5.7% ) – pigmented type. Patients from the study group received one session of photodynamic therapy using laser unit "LAMI" (662 nm) after 2 hours of application of fotoditazin 0.5% gel at dose of 0,2-0,3 ml per 1 cm2 of actinic keratosis focus with the following parameters: the energy density of the laser radiation – 200 J/cm2, power density – 0.14–0.48 W/cm2. In the control group patients underwent cryotherapy with liquid nitrogen with an exposure of 30-60 sec. The comparative analysis of the immediate results showed a tendency for the efficacy of photodynamic therapy to increase (the rate of complete regression was 92.5%) compared with cryotherapy (85.0%) (p>0,05). There were also a tendency for long-term results after photodynamic therapy to improve: three-year recurrence-free survival was 94.6% and 88.2%, respectively. For the photodynamic therapy there were significantly fewer adverse reactions, the epithelization time in lesions was significantly shorter. Compared with cryotherapy the photodynamic therapy provided significantly better cosmetic results (p

The review is on treatment of keratoacanthomas using photodynamic therapy. The defining characteristic of keratoacanthoma among epithelial tumors is a rapid spontaneous regression in the case of typical keratoacanthoma and long-term persistence, recurrence and common malignant transformation to squamous cell carcinoma in the case of atypical keratoacanthoma. In recent years, photodynamic therapy which is an effective method of treatment of different types of cancer and pre-cancer diseases of the skin including actinic keratosis, Bowen’s disease, basal cell carcinoma, is increasingly used in clinical practice. There are few data for photodynamic therapy in the treatment of keratoacanthoma. The analysis of the literature shows that using of photodynamic therapy in the set of treatment modalities in patients with keratoacanthoma improves the efficacy and reduces the terms of the therapy. In all investigations except one there was complete tumor regression in 100% patients with keratoacanthoma who underwent photodynamic therapy. In one study complete tumor regression was observed in 66.7% of patients with atypical keratoacanthoma after photodynamic therapy. The follow-up of patients in all analyzed studies accounted for at least 2-3 years. During this time none of the patients had evidence for recurrence. This approach has minimal restrictions for application. Thus, photodynamic therapy may become a therapeutic alternative to surgical treatment of keratoacanthoma with good clinical and cosmetic results.

Characteristics of diagnosis and treatment of different types of primary vaginal cancer are highlighted, the role and place of brachytherapy as independent method or combined treatment modality for this pathology is shown in the review. Epidemiological data on incidence of vaginal cancer in Russia are represented, presumptive mechanisms for development of the disease, risk factors, histological types, features of the course, clinical presentation, diagnostic algorithm are described. Treatment methods for primary vaginal cancer according to world standards such as surgery, radiotherapy and systemic drug therapy are covered. Specifics of radiological methods of treatment (low-dose rate and high-dose rate brachytherapy, including the combination with external beam radiotherapy) according to the stage of the disease, are shown in details. The results of several large foreign clinical trials for efficiency of different methods of radiotherapy are discussed. The combination of brachytherapy on primary tumor with external radiation therapy to the lymph nodes was confirmed to be the most effective modality. The conclusion on opportunities of different methods of radiotherapy in treatment of vaginal cancer was made.

The study of the functional morphology of rat sarcoma M-1 after photodynamic therapy using bacteriopurpurinimide disulfide derivative (disulfide-BPI) as a photosensitizer is described. The research methods included immunohistochemistry for PCNA and CD31, evaluation of mitotic activity and apoptosis of tumor cells, as well as computer analysis of microscopic images. Photoinduced antitumor effect was shown to be due to the destruction of sarcoma M-1 vascular bed, the rapid inhibition of proliferative activity and devitalization of tumor cells by apoptosis and necrosis. It is reasonable to suppose that in the early stages after photodynamic therapy destruction of the microvasculature and photocytostatic shock of tumor cells with subsequent development of necrosis are caused by direct influence of the light flux on sensitized cellular elements in parenchyma and stroma of tumors. The efficiency of photodynamic therapy with the novel photosensitizer is determined by the sequence of destructive and inflammatory changes in tumor parenchyma and surrounding tissues, as well as repopulation potential of tumor cells survived after treatment.

The review is devoted to application of brachytherapy for treating the localized prostate cancer (PC). Statistics for incidence and detectability of this pathology and its dynamics for recent years are represented. Brief analysis of other methods which are conveniently used for treatment of PC, such as radical prostatectomy and external-beam radiotherapy, was performed. Advantages and disadvantages of these methods have been discussed. Brief history about the development of brachytherapy from first experience to wide-spread use in clinical practice is reported. The detailed review of series of large trials from Russia and other countries for efficiency and safety of brachytherapy in patients with prostate cancer for recent 15 years is also represented. Two types of brachytherapy in current clinical oncology i.e. low-dose technique with permanent implantation of microsources and high-dose temporary isotope implantation, specifics of its application in different groups of patients have been described. The procedure of brachytherapy and its three main steps i.e. planning, implantation and control assessment after implantation have been characterized in details. The conclusion about benefits of using of brachytherapy in the treatment of prostate cancer as minimally invasive and efficient method was made.