[Proton three-demensional conformal radiosurgery of arteriovenous malformation of the brain].

The proton beam radiosurgery was performed to 65 patients with brain AVM since December, 2001 till February, 2012, in Joint Institute for Nuclear Research, Dubna, Russia. We have analyzed data for 56 patients. The follow up time varied from 24 to 109 months. The volumes of brain AVMs varied from 0.92 to 82 cc. The mean isocenter dose was 24.61 +/- 0.12 Gy E. The edge of the target was included in 70-90% isodose. The proton beam surgery was splitted in two similar doses and delivered in two consecutive days in vast majority of patients. Ten patients were missed for follow up due to some reasons. The radiosurgery was resulted in full obliteration of AVM in 23 from remaining 46 (50%) patients. There was full obliteration in 46.6% of patients with volume of AVM 10-24.9 cc; and this rate is significantly more than for photon radiosurgery of same size brain AVM. The partial obliteration was obtained in 21 patients. Only one patients suffered hemorrhage from partially obliterated AVM. We could not see any effect in 2 patients. There were delayed radiation toxicity in 5 patients in 12 months after treatment: in 4 patients, these reactions were assessed as 2 according to RTOG scale and were dissipated in 1 month after commencement of corticosteroid treatment. There was radiation necrosis in one patient, and it was relieved in 12 months after several courses of dehydration and corticosteroid therapy. So, proton beam therapy is effective and safe modality for treatment of inoperable brain AVM, especially of middle- and large size.

[Primary lymphomas of bones and soft tissues: comparative assessment of treatment results].

AIM: To evaluate the efficiency of intensive polychemotherapy (PCT) in adult patients having diffuse large B-cell lymphoma (DLBL) of bones and soft tissues with and without poor prognostic factors (PPF). SUBJECTS AND METHODS: Out of 58 enrolled patients, 51 were diagnosed as having DLBL. Burkitt's lymphoma (BL) was diagnosed in 6 patients. One patient had marginal zone B-cell lymphoma. Thirty-five patients with DLBL (10 patients with PPF and 25 without PPF) and 3 patients with BL were treated with the CHOP/R-CHOP regimen. The NHL-BFM-90 program was used in 3 patients with BL and 16 with DLBL (15 patients with PPF and 1 patient without PPF). RESULTS: After radiotherapy, the patient with marginal zone B-cell lymphoma achieved a 20-month remission; three BL patients receiving CHOP died. All the BL patients receiving NHL-BFM-90 achieved complete remissions of 48 to 72 months. In 9 patients having DLBL without PPF, who received CHOP, five-year overall and event-free survival rates were 100%; in 22 patients with PPF, these were 50 and 45%, respectively. In the patients with and without PPF, who received CHOP/R-CHOP, the survival rates differed statistically significantly (p = 0.01; logrank test). In the group of 15 patients having DLBL with PPF, who were treated with the NHL-BFM-90 protocol, 14 achieved an average remission of 17 months. In the patients having DLBL with PPF who used NHF-BFM-90, therapeutic efficiency was significantly higher (p = 0.05; Fisher's exact test). CONCLUSION: Differential therapy for primary lymphomas of bones and soft tissues indicated that the NHL-BFM-90 protocol used in the PPF group was significantly more effective than the CHOP regimens.

[Proton "radiosurgery" of cerebral arteriovenous malformations].

Arteriovenous malformations (AVM) are vascular lesions arising from impaired angiogenesis at the stage of transformation of primary embryonic arteriovenous anastomoses into capillaries. Commonly AVMs manifest with spontaneous hemorrhage. Stereotactic radiosurgery is method of choice for treatment of surgically inaccessible AVMs, which are characterized by high risk of damage of adjacent critical structures. In addition, stereotactic radiosurgery is used either as a component of complex management of large AVMs or pre-planned procedure combined with endovascular intervention, or as a second line therapeutic option in residual AVM after subtotal surgical resection. Comparing with photons protons due to their unique physical properties have advantages in spatial spread of dose thus allowing to significantly decrease integral dose to the surrounding brain tissue when treating large AVMs with complex shape proximal to critical structures.