A personalized approach to MR monitoring of patients with low-grade gliomas after surgical treatment

INTRODUCTION . Understanding the nonlinear process of progression of low grade gliomas (LGG) necessitates the identification of factors that influence their biological behavior and the revision of commonly accepted recommendations regarding their MR monitoring. Early detection of continued tumor growth, including malignant transformation, before the first symptoms appear and neurological deficits develop is the main goal of surveillance after tumor resection. At present, the optimal frequency of follow-up MR examinations for patients with LGG has not been clearly defined. MATERIALS AND METHODS . The study group consisted of 52 patients with LGG of supratentorial localization who underwent reoperation for advanced LGG between 2019 and 2023. Inclusion criteria: age at the time of diagnosis older than 18 years; histologically and molecularly genetically verified LGG; no tumor contrast accumulation according to MRI before the first surgery; radiopharmaceutical accumulation index according to PET-CT with methionine less than 1.7; Ki-67 expression level less than 6 %; no vascular proliferation and endothelial swelling. To identify the factors influencing the recurrence-free survival of LGG, the peri- and postoperative treatment was analyzed. Comparative data analysis and statistical processing was performed using x 2 test and proportional hazards model in patients with progression. RESULTS . Based on the findings, MRI follow-up schedules for patients after initial treatment are proposed. After surgical resection without adjuvant treatment, the recommended interval of MRI studies for patients with LGG is every 3–4 months until its progression, while in patients with oligodendroglioma who underwent total resection or received a combination of radiation therapy and chemotherapy, it is preferable to perform MRI every 6–9 months after surgery until tumor progression. For patients with astrocytoma it is recommended to perform MRI control every 3–4 months regardless of the degree of resection and every six months for patients who have received a combination of radiation therapy and chemotherapy. CONCLUSION . The MR monitoring schedule used should take into account the individual characteristics of both the patient with LGG and the tumor itself. Determination of optimal timing of MR studies is crucial in early detection of malignant transformation and/or tumor progression.