https://www.selleckchem.com/products/pf-04929113.html 0). The effectiveness of PDT was assessed basing on the presence / absence of complaints, data from visual observation of changes in the area of treated lesions and morphological examination data at 3 and 6 months after treatment (WHO criteria). No serious adverse reactions associated with the introduction of FS and PDT session were observed no allergic reactions (Quincke's edema, urticaria, drop in blood pressure, bronchospasm), no symptoms of skin phototoxicity. In the specified control patients' observation terms, the remission of disease clinical symptoms (an itch in the area of vulva) in the treated pathological centers as well as high frequency of clinical and morphological regressions were noted. The obtained results indicate the relevance and prospects of further research in the field of laser technology and PDT as options for organ-preserving treatment of premalignant diseases of vulva.Radical surgery over large subtentorial tumors is associated with a high risk of postoperative complications. Despite significant development of imaging technology, intraoperative monitoring, and microsurgical treatment, problems one of tottal and safe large subtentorial tumors removal remain unsolved. The most critical problem relating to large tumors of this localization is postoperative edema. Also brainstem ischemic stroke is not rare and this would partly due to the tumors overgrowthing the vertebral and basilar arteries. Retrospective analysis of 59 patients with large (more than 3 cm) tumors to the posterior cranial fossa operated over 2015-2019 yy. There was gross total tumor removal in 49 (83%) patients; subtotal tumor removal in 5 (8,5%) patients; partial tumor removal in 5 (8,5%) cases. Complications occurred in 15 (25%) patients. The use of ventral craniobasal aprroaches and their combination with posterior-lateral approaches to the large subtentorial tumors allows rapid and early, effective brain stem decompre