Response assessment in neuro-oncology (RANO) criteria: application in clinical research and routine practice

General principles for evaluating the effectiveness of anticancer treatment in oncology. RECIST criteria: Based on various instrumental methods for assessing tumor foci in general oncology, the standard RECIST 2009 criteria (RECIST 1.1) for evaluating solid tumors are used to assess tumor dynamics. These criteria are used in computed tomography and magnetic resonance imaging and, in some cases, in conventional radiography. In neurooncology, both in clinical trials and in routine clinical practice, RANO criteria rather than RECIST and Macdonald criteria should be used due to the specific anatomy and biological behavior of CNS tumors, as well as the features of neuro-imaging against the background of anticancer drug therapy and modern methods of radiation therapy. Based on the experience of the application of the Response evaluation criteria in solid tumors (RECIST) criteria and the McDonald criteria, RANO-HGG includes among the parameters for evaluating MRI in the T1 mode with contrast enhancement and T2/FLAIR modes, the use of corticosteroids, as well as the dynamics of clinical status; defines the concept of «pseudo-progression» and «pseudo-response to treatment», which have become relevant in the era of modern methods of radiation therapy and anti-angiogenic and other drugs that affect vascular permeability. RANO criteria for low-grade gliomas: MR semiotics is similar to other processes such as demyelination or ischemia; in addition, the slow growth characteristic of these tumors often complicates the assessment of the disease response, therefore the concept of «low response to treatment» was introduced (reduction in the size of the measured foci by 25-50%). RANO criteria for metastatic lesions of the central nervous system (brain metastases) and RANO criteria for leptomeningeal metastasis: The purpose of RANO-BM is to determine the activity of potential agents against brain metastases and to determine the appropriate endpoints for clinical trials; it is important that these criteria are needed for a more accurate assessment of events with intracranial foci than in the RECIST system, according to which the diameters of intracerebral tumor foci should be summed up with the diameters of both the main tumor and distant metastatic foci. RANO criteria for immunotherapy - iRANO: their development was attributable to the specific reactions to immunotherapy - an increase in the area of brain edema against the background of the onset of immunotherapy; this scoring system makes it possible to consistently and logically differentiate the tumor response to treatment from tumor progression; leptomeningeal metastasis is a dangerous and late complication of a disseminated oncological process with damage to the central nervous system, most often found in breast and lung cancer, as well as in hematological malignant neoplasms. Neurological Assessment in Neurooncology: although the Macdonald and RANO criteria include clinical status in the definition of progression, there is no quantitative measure to its determination. To address this limitation and quantify clinical outcomes, the Neurological Assessment in Neuro-Oncology (NANO) was created. RANO-corticosteroids: corticosteroids in various doses are an integral part of the clinical management of patients with CNS tumors at various stages of treatment; however, it has been suggested that patients requiring steroids for longer periods of time or at higher doses have a shorter overall survival. In addition, steroid use, along with age and work performance, was associated with a poor prognosis. RANO-PET/CT: The latest revision of these RANO/PET group recommendations was published in 2019. In 2017, recommendations for the use of PET/CT with amino acid tracers in patients with meningioma were also published; the purpose of these recommendations was to provide clear instructions on technical parameters, indications for use and interpretation of the PET/CT results obtained in neurooncology, with a clear understanding of the possibilities and limitations and, ultimately, clear algorithms for this examination method.

neurooncology, brain metastases, immunotherapy, corticosteroids, RECIST criteria, Macdonald criteria, RANO criteria