Imaging Recommendations for Diagnosis, Staging, and Management of Central Nervous System Neoplasms in Adults: CNS Metastases

Simple Summary Brain tumors that spread from cancer elsewhere in the body (brain metastases) are becoming more common due to better cancer detection. While historically the outlook for patients with brain metastases was poor, new minimally invasive surgeries and targeted therapies are improving prognoses. Imaging features also depict responses to treatment and help identify the cause of patients' symptoms worsening due to disease or therapy. The development of new MRI techniques, the use of artificial intelligence, and advanced therapeutic delivery systems are creating even more powerful tools that are directly contributing to improving patient care and better survival for patients with brain metastases. This article explores the screening and diagnostic and prognostic roles of various imaging modalities, and recommends standard guidelines in the management of cancer patients to improve the overall survival rate.Abstract Brain metastases (BMs) are the most common central nervous system (CNS) neoplasms, with an increasing incidence that is due in part to an overall increase in primary cancers, improved neuroimaging modalities leading to increased detection, better systemic therapies, and longer patient survival. Objective: To identify cancer patients at a higher risk of developing CNS metastases and to evaluate associated prognostic factors. Methods: Review of imaging referral guidelines, response criteria, interval imaging assessment, modality of choice, as well as the association of clinical, serological, and imaging findings as per various cancer societies. Results: Quantitative response assessment of target and non-target brain metastases as well as an interval imaging protocol set up based on primary histological diagnosis and therapy status are discussed as per various cancer societies and imaging programs. Conclusion: Predictive factors in the primary tumor as well as independent variables of brain metastases like size, number, and response to therapy are necessary in management. The location of CNS metastases, symptomatic disease, as well as follow up imaging findings form a skeletal plan to prognosticate the disease, keeping in mind all the available new advanced therapy options of surgery, radiation, and immunotherapy that improve patient outcome significantly.