Keyword: Magnetic Resonance Imaging

ABSTRACT: Introduction: Renal cell carcinoma brain metastases are a complication of oncological disease and are associated with an unfavorable prognosis. Stereotactic radiosurgery is one of the main methods of local treatment for intracranial metastases. Data on its outcomes in renal cell carcinoma brain metastases in Kazakhstan are limited.
Objective: To evaluate overall survival, intracranial progression-free survival, and local control after stereotactic radiosurgery.
Materials and Methods: A retrospective cohort study was conducted on patients with renal cell carcinoma brain metastases who underwent stereotactic radiosurgery using the Gamma Knife at the National Center for Neurosurgery between 05.10.2021 and 18.03.2026. The median age was 60 years (44–75), the median Karnofsky Performance Status score was 75 (50–90), and the median prognostic score was 1.5 (0–3.5). Extracranial metastases were present in 25 patients (78.1%), and 21 patients (65.6%) received systemic therapy prior to radiosurgery. Overall survival was assessed in 32 patients; intracranial progression-free survival and local control were assessed in 28 patients with available follow-up magnetic resonance imaging (MRI) studies. For local control assessment, 89 treated lesions were analyzed. Survival rates were calculated using the Kaplan–Meier method. The study was approved by the Bioethics Commission No. 1 of the "National Center for Neurosurgery" JSC (protocol extract No. 7 dated April 13, 2026) and conducted in accordance with the ethical principles of the Declaration of Helsinki.
Results: The median overall survival was 22.1 months. Overall survival rates at 6, 12, and 24 months were 71.4%, 60.8%, and 47.9%, respectively. Among the 28 patients with follow-up MRI studies, the median follow-up period was 4.5 months (1.23–36.13), and the median intracranial progression-free survival was 12.7 months. Intracranial progression was recorded in 11 patients: 9 developed new brain metastases, and 2 had leptomeningeal dissemination. Local control was analyzed in 89 treated metastatic lesions in 28 patients. One case of local progression of a treated lesion was recorded by MRI, detected 9.57 months after treatment. Local control at 6 and 12 months was 100% and 96.8%, respectively.
Conclusions:  Stereotactic radiosurgery using the Gamma Knife provides high local control of renal cell carcinoma brain metastases. Intracranial progression was predominantly due to the appearance of new metastatic lesions and leptomeningeal dissemination, rather than progression of previously treated lesions. The obtained results demonstrate the high efficacy of the Gamma Knife in achieving local control in patients with renal cell carcinoma brain metastases.

ABSTRACT: Background: Dense breast tissue reduces mammographic sensitivity and raises breast cancer risk. Supplemental imaging and artificial intelligence supported mammography reading have been tested prospectively. The European Society of Breast Imaging recommends supplemental magnetic resonance imaging for extremely dense breasts, whereas the American College of Physicians in 2026 advised against it for average risk women with dense breasts. This review summarises what the principal studies measured and found.
Objective: To review the published evidence on both strategies in dense breasts, reporting each study's endpoints and results.
Materials and Methods: Narrative review of primary publications, published online 2019 to 2025, quoted verbatim. Four large prospective multicentre studies reporting on dense breasts were selected, two per strategy: the randomised trials DENSE (Netherlands, magnetic resonance imaging) and BRAID (United Kingdom, abbreviated magnetic resonance imaging, automated ultrasound and contrast-enhanced mammography), and the observational studies PRAIM (Germany, artificial intelligence supported double reading) and ASSURE (United States, artificial intelligence supported single reading with safeguard review).
Results: DENSE randomised 40,373 women with extremely dense breasts and normal mammography to invitation for supplemental magnetic resonance imaging or to mammography alone: interval cancers 2.5 versus 5.0 per 1000; among the 59% accepting, detection was 16.5 and false positives 79.8 per 1000. BRAID randomised 9361 women with dense breasts and a negative mammogram: detection was 17.4 per 1000 examinations with abbreviated magnetic resonance imaging, 19.2 with contrast-enhanced mammography and 4.2 with automated ultrasound, the contrast-based modalities not differing significantly; recall 9.7%, 9.7% and 4.0%, median invasive size 10, 11 and 22 millimetres. In PRAIM (463,094 women), artificial intelligence supported double reading was associated with detection of 6.7 versus 5.7 per 1000 (17.6% higher) and non-inferior recall; in dense breasts the 18.7% increase was not statistically significant. In ASSURE (579,583 tomosynthesis examinations, single reading), detection with the artificial intelligence workflow was 5.6 versus 4.6 per 1000 (21.6% higher), recall 11.1% versus 10.6%, and detection in dense breasts 22.7% higher.
Conclusions: In BRAID, abbreviated magnetic resonance imaging and contrast-enhanced mammography detected three times as many invasive cancers as automated ultrasound, at half the size with more than twice the recall, and did not differ significantly from each other. In DENSE, invitation to supplemental magnetic resonance imaging halved the interval cancer rate. Artificial intelligence support was associated with higher detection in PRAIM without higher recall and in ASSURE with slightly higher recall; neither was randomised. No included study measured breast cancer mortality; survival benefit remains undemonstrated and overdiagnosis unquantified.