[New opportunities for proton therapy in Russia].

On November 23, 2015 in Protvino of the Moscow Region there was begun proton therapy using Russia's first medical therapeutic complex "Prometheus" produced by JSC "PRO- TOM" and certified to treat patients with head and neck tumors. The complex allows irradiating patients with active scanning beam. Energy of beam is 30-250MeV and maximum field size is 10 cm vertically and 40 cm horizontally. The manufacturer declared parameters were confirmed during preclinical stud- ies. By April 8, 2016 the successful proton therapy received 20 patients with complex "targets" mostly located, from the point of view of radiation tolerance, near the critical structures.

[Radiotherapy for local recurrences of prostate cancer after radical prostatectomy].

Basic and universally accepted method of treatment of local recurrence is local radiotherapy. The most researchers tend to favor of the early start of radiotherapy: PSA no more than 0.5-1.0 ng/ml, until manifestation of signs clinical recurrence of disease as well as in terms of PSA doubling for at least 6 months. Morphological verification of recurrence is not a necessary condition for the administration of radiotherapy. In cases of impossibility of verification or its negative result, it should focus primarily on the dynamics of PSA and data of instrumental examination. Standard methods remote radiotherapy (3D-conformal radiotherapy, intensity modulated radiation therapy--IMRT) can be successfully used in these patients at ODS 66-70 Gy, with the escalation of SOD 70 g more justified in a limited category of patients. Joining of hormone therapy in neoadjuvant and parallel with radiotherapy modes did not show significant improvement in disease-free survival rates however in certain categories of patients had advantages.

[Radiosensitivity of bone metastases from tumors in different primary sites].

The purpose of the current clinical trial was to evaluate efficiency of palliative external beam radiotherapy for symptomatic bone metastases from different primary tumors. The randomized study included 427 patients, treated for 616 sites of bone lesions. Breast was the primary site in 67,5% of cases, prostate and lung--in 7,5% each, renal--in 5,5%, other tumors--in 12%. The most frequent treatment site was the spine--47,8%, followed by pelvis--30,8%, long bones--14,4%, sacrum--2,9% and other sites--4%. The main indication for irradiation was pain not alleviated by systematic drug therapy. Radiotherapy protocol included 3 hypofractionation regimes with total dose of 26 Gy, 19,5 Gy and 13 Gy by 3, 4 and 2 fractions of 6,5 Gy correspondingly and standard treatment schedule with total dose of 26 Gy. The average follow-up period was 56 months. General pain relief (complete and partial) was observed in 96,1% of sites and was independent of primary tumor, metastases localization and irradiation schedules. Complete response rate (CRR) was higher for bone metastases form breast and prostate cancer 64,2% and 58,7% correspondingly in comparison with lung and renal cancer--43,5% and 26,5% respectively (p<0,05). At small number of observations metastases from melanoma and sarcomas proved high radiosensitivity with CRR 75% and 66,7% correspondingly. CRR for spine and pelvis localization of metastases was similar--63,4% and 59,3%, slightly lower for long bones--48,3% and significantly lower for sacrum isolated metastases--27,8% (p<0,05). CRR was higher for standard treatment schedule and significantly increased for 2, 3 and 4 fractions of 6,5 Gy correspondingly (p<0,03). In the multifactorial analysis tumor primary site and pain intensity before radiotherapy were the only independent prognostic factors of CRR. Therefore histogenesis of primary tumor is a predictor of radiosensitivity of bone metastases, it significantly affects the complete pain response rate. It is expedient to use hypofractionation regimes of 3 fractions of 6,5 Gy (total dose 19,5 Gy) for palliative radiotherapy of bone metastases in case of breast, prostate cancer, sarcomas and melanoma and 4 fractions of 6,5 Gy (total dose 26 Gy) in case of lung and renal cancer.