Irradiation of the  tumor through the  ridge  filters  in order  to reduce  the  damage of the  normal tissues while maintaining the same damage to the neoplastic tissue  as with uniform field is used for many decades. In recent years, a positive effect has been demonstrated using synchrotron radiation and beams of accelerated protons with radiation fields diminished to 25-100 micrometers with the same distances between them.  Less skin  damage achieved while  maintaining the  required level of large  neoplasms eradication in the  case  of X-ray and gamma  irradiation through ridge  filters  can be partially explained by the features of the physical distribution of the dose over the depth of the irradiated tissue,  namely, the “merging” of fields at depth. But the  good  results from  the  use of the  ‘hills and  valleys’ in radiation fields  created by the  modern radiation sources  have attracted attention to radiobiological issues for explaining the principal differences in reaction to  spatial fractionation of the  absorbed dose  between tumor and  normal tissues. We  are  talking about the  role  of the  so-called ‘communal effect/bystander effect’, the  effect  of radiation on the  immunological processes, the  differences in damage and  restoration of the  microvasculature in normal and  tumor tissue, etc. Although there  is the lot of publications concerning experimental studies of the effectiveness of ‘spatial dose fractionation’, as well as those  considering radiobiological mechanisms of the  observed expansion of the ‘therapeutic interval’, there  is still no clarity in this issue. The purpose of this review is to systematize the available data on the clinical  and experimental confirmation of the effectiveness of ‘spatial fractionation’ and the  various  explanations of its  advantages over conventional, uniform dose  distribution. Special  attention is paid  to the  issues  of combination of spatial fractionation with  superhigh dose rate  irradiation (FLASH-radiotherapy) on the  new  radiation facilities, including proton accelerators, which  are  now  in use in this country.

Children are not  “miniature” adults!  Most experts around the  world  recognize the  differences between adult and pediatric thyroid cancer and emphasize the need for specific guidelines for the pediatric population. The American Thyroid Association (ATA) first developed separate Guidelines for the Treatment of Pediatric Thyroid Nodules and Carcinoma (hereafter, ATA Guidelines) in 2015 [1], which  has not been revised  to date. In September 2022, the European Thyroid Association (ETA) published its Guideline on the Management of Pediatric Thyroid Nodules and Differentiated Thyroid Carcinoma (hereafter, ETA Guidelines) [2]. The aim of our article, in anticipation of the revision of Russian  clinical  guidelines for the treatment of pediatric thyroid cancer,  is to inform specialists in the field of radioiodine therapy (RIT) with the key recommendations of the ETA.

Purpose: To improve  the  differential diagnosis of high-grade gliomas  and solitary  metastases by introducing the diffusion-kurtosis magnetic resonance imaging technique into the MRI scan protocol.

Material and methods: The study included 43 patients who underwent examination and treatment at the N.N. Blokhin  National Research Medical  Center of Oncology from  October 2019 to March  2022, in which, according to magnetic resonance imaging, solitary  formations in the brain  substance were detected. A total of 43 neoplasms were found  in the substance of the brain,  of which:  17 glioblastomas in 17 patients (40 %), 25 solitary  metastatic tumors of lung,  breast, melanoma and kidney  cancer  (60 %). We evaluated the  tumor size, diffusion and kurtosis parameters, such as mean kurtosis (MK), axial kurtosis (AK), radial  kurtosis (RK), kurtosis anisotropy (KA), radial  diffusion (RD), fractional anisotropy (FA), relative  anisotropy (RA), tortuosity of the trajectory (TTD).

Results:  Statistically significant differences (р < 0.05) in  such  parameters of diffusion and  kurtosis in the  tumor as kurtosis anisotropy (KA), fractional anisotropy (FA) and tortuosity of the  trajectory (TT) were revealed.  Significant differences between solitary  metastases and malignant glial tumors based  on diffusion and kurtosis values such as mean kurtosis (MK), axial kurtosis (AK), radial kurtosis (RK), radial diffusion (RD), and relative  anisotropy (RA) (criteria where р > 0.05) was not detected.

Background: Cervical cancer occupies one of theleading places in cancer incidence in women. Preservation of residual tumor in  patients with  cervical  cancer  after  completion of combined chemoradiotherapy is a prognostically unfavorable factor. Detection of an early tumor response to chemoradiation therapy is of great importance for choosing the optimal treatment tactics.

Purpose: To study  the  possibilities of MRI in assessing the  effectiveness of detecting an  early  tumor response in patients with locally advanced cervical cancer  after combined chemoradiotherapy.

Material and methods: The results of magnetic resonance imaging of the  pelvic organs, data  of laboratory, cytological and postoperative histological studies of 174 patients with locally advanced cervical  cancer were analyzed  and compared.

MRI of the pelvic organs was performed before  the start  of treatment to assess  the extent  of the process (primary study) and 6 weeks after the completion of combined chemoradiotherapy to assess the effectiveness of the treatment and detect residual tumor (control study).

Conclusion: Magnetic resonance imaging of the pelvic organs using a standard research protocol, including obtaining diffusion-weighted images and dynamic contrast studies, is a highly informative method for staging locally advanced cervical cancer  and assessing the tumor response to treatment.

Glioblastoma is the  most malignant primary brain  tumor. For treatment uses a combined regimen that is currently available:  surgery,  radiation and chemotherapy. However,  so far the median survival  of patients does not exceed 14 months. In this connection, there  is a constant search for effective methods. Improvement in radiation therapy has led to the possibility of its intraoperative, which  is a practical and effective  method aimed at getting rid of the remaining tumor cells, reducing the spread of the tumor and filling the therapeutic gap between surgery  and subsequent chemotherapy and radiation therapy. Intraoperative radiation therapy (IORT) allows  you to  deliver  the  required tumoricidal dose  exactly  to  the  target, minimally affecting the surrounding healthy tissues.

Goal: Establishment of the  safety of intraoperative irradiation of patients with  malignant gliomas  with the INTRABEAM  device (Carl ZEISS, Germany) with a dose of up to 40 Gy on the applicator.

Material and methods: The study  involved  15 patients, the average  age of which  was 51 years, the ratio of  men  and  women  was  4:6, the  average  Karnofsky index  before  surgery  was  97. After  surgical removal of the  tumor, an  express  biopsy  was performed. Next,  intraoperative irradiation was performed with  the INTRABEAM  device (Carl ZEISS) at a dose of 40 Gy, followed by an assessment of the Karnofsky index, early postoperative and delayed possible complications.

Results:  In all patients operated on with  intraoperative irradiation and subsequent adjuvant radiochemotherapy, the  method was  well  tolerated, there  were  no  wound  healing features or  identified complications, there  were no cases of wound  liquorrhea, wound  inflammation.

Conclusion: Intraoperative irradiation after surgical removal of the tumor can be recommended as a safe method for the treatment of malignant gliomas  in addition to existing combination therapy.

Relevance: Glial tumors (GTs) amount for about 60 % of all primary CNS tumors. GTs highly express VEGF. Standard approaches to GT treatment do not  involve modification of the  radiation therapy plan.  Adaptive stereotactic radiotherapy (ASRT) allows such correction. The combination of ASRT with bevacizumab (B) or dexamethasone (D) improves the outcomes of patients with GTs, but the effectiveness of therapy varies from patient to patient. B and D are known  to have different effects on malignant glioma cells and components of the VEGF system.

Purpose: To reveal specific  levels of the VEGF system components in the blood of men with cerebral GTs with different effectiveness of combination ASRT.

Material and methods. One  month after  radical  surgery,  men  with  GTs  received  ASRT with  standard fractionation on the Novalis Tx linear  accelerator (Varian): single  fraction dose = 2 Gy, total  dose = 60 Gy, 30 fractions, using a three-layer stereotaxic mask. ASRT was combined with B (i/v, 5 mg/kg, once every 2 weeks), n = 30, and  with  D (i/m, 4 mg, twice  a day during 45 days), n = 30. Blood levels of VEGFA,  sVEGFR1  and sVEGFR2 were measured by IFA before and after ASRT.

Results: Before  treatment (ASRT+D), levels of VEGFA  were  1.5 times  (р < 0.01) higher, and  sVEGFR1 was 3.1 times  lower  in patients with  future progression, compared with  patients with  other  responses to treatment; in partial response, sVEGFR was 1.8 times  (р < 0.01) higher than  in stabilization. After treatment (ASRT+D), sVEGFR1 levels reduced by 1.4 times (р < 0.001) in stabilization and by 2.2 times in partial response, together with  VEGFA  increase by 3.0 times  in  stabilization only; in  progression, sVEGFR1  increased  by 2.3 times.  Before  treatment (ASRT+B), levels  of VEGFA  in  patients with  partial and  complete responses were on average  1.4 times  (р < 0.01) lower than  in stabilization; sVEGFR1 in partial response was 4.4 times lower than  in stabilization and 2.2 times  lower than  in complete response; sVEGFR2 in complete response was 1.3 times  (р < 0.02) lower than  in partial response. After treatment (ASRT+B), VEGFA levels elevated:  in complete and partial responses on average by 14.8 times,  in stabilization by 9.7 times.

Conclusions: In men with cerebral GTs, blood levels of the VEGF system  components before  treatment differed in  patients with  different future responses to  combination ASRT  with  B or  D,  which   allows prediction of the effectiveness of such therapy even before it is started. This connection is especially obvious for combination ASRT with B.

Klatskin’s tumor is  a  rare  malignant neoplasm characterized by  the  absence of  specific   symptoms, challenges in verification and  difficulties in assessing the  true extent  of the  tumor. We present a clinical case  of a patient with  hilar  cholangiocarcinoma. The  patient received  almost the  entire modern complex of  radiologic examinations  for  preoperative  staging.  However,   concominant  cholangitis, hard-to-reach anatomical localization and tumor’s  creeping-growth distorted the results of instrumental studies. The true volume of the lesion was detected only intraoperatively and resulted in an expansion of liver resection volume.

The  study  analyzed  the  clinical  observation of the  psychological characteristics  of a woman  diagnosed with  breast cancer,  who refused  part  of the proposed therapy, and had no contraindications to start  special treatment.

Patient Yu.F., born in 1953, diagnosis: cancer  of the right  breast T1NxM0 ЭР(95 %), ПР(15 %), Her2neu(0), Ki67 (5 %), refused  for personal reasons from the surgical treatment proposed at the 1st stage  (a written refusal was taken), in connection with which  a course  of hormone therapy was prescribed, a course  of remote radiation therapy according to a radical program. When assessing the psychological profile of the patient, the data obtained demonstrate the presence of paradoxical hyperprotection in the patient who refused part of the treatment. Her psychological profile is similar to the psychological characteristics of women with breast cancer, whose course  of the disease ended  in death.  In a study conducted in 2021, data were obtained on women with  a negative outcome of the  disease (death), who were convinced of their  own luck and in the  ability  to control what was happening, used a wide range  of coping  strategies, were more resilient, are optimistic and had a pronounced internality in comparison with women  in whom the disease went into stable  remission.

The expression of prostate-specific membrane antigen (PSMA) on the surface  of prostate cancer  cells is increased with  tumor progression, which  is the  basis  for a theranostic approach in the  treatment of these patients. The PSMA ligand, labeled with the therapeutic radionuclide lutetium-177 (¹⁷⁷Lu), delivers ¹⁷⁷Lu beta particle radiation to PSMA-expressing prostate cancer  cells. Currently, PSMA-targeted radioligand therapy with  the  radiopharmaceutical  ¹⁷⁷Lu-PSMA-617 is  approved for  the  therapy of  patients with  metastatic castration-resistant prostate cancer  (mCRPC). We present a clinical  case  of successful use of this  method of treatment in our  center in a patient with  mCRPC,  progressing after  two  lines  of therapy — hormone therapy with  new generation of androgen signal  inhibitors (abiraterone, enzalutamide) and  chemotherapy with docetaxel.