CNS Involvement in Non-CNS Tumors

An interdisciplinary consensus on the management of brain metastases in patients with renal cell carcinoma

“…MRI with and without administration of a gadolinium-based contrast agent (GBCA) is preferred to computed tomography (CT) because of its superior soft tissue contrast and increased sensitivity for detecting BMs. 1,31,32 In an emergency setting, CT is usually performed because of its wide availability and rapid accessibility; preferably, CT should be performed with and without an iodine contrast agent. 33 Optimizing the sensitivity of MRI is clinically very important because MRI findings greatly influence key decisions in therapy strategy and prognostication.…”

“…34 High (double)-dose contrast agent administration can be considered for instances in which sensitivity needs to be maximized, such as when focal therapy is being considered in a patient with adequate renal function. However, it should be taken into account that increasing the contrast dose may also lead to an increase in false-positive findings 1,31,34 and might not be feasible in a patient with mRCC who underwent prior nephrectomy because of limited renal function.…”

“…In concordance with the Response Assessment in Neuro-Oncology (RANO) working group's criteria on BMs (RANO-BM), an MRI slice thickness of ≤1.5 mm (no gap) is preferred. 31 Volumetric spin echo (SE) techniques (eg, SPACE [variable flip angle turbo SE]) outperform volumetric gradient recalled echo (GRE) sequences (eg, magnetization-prepared rapid gradient echo), but 3-dimensional (3D) GRE imaging is still preferred over 2D SE because of superior lesion detection with thin-slice volumetric acquisition. 31,32,34 Assessing for BM at Progression Progressive systemic disease When patients with mRCC show progressive disease systemically without neurologic symptoms, it is a matter of debate whether brain imaging is required.…”

“…31 Volumetric spin echo (SE) techniques (eg, SPACE [variable flip angle turbo SE]) outperform volumetric gradient recalled echo (GRE) sequences (eg, magnetization-prepared rapid gradient echo), but 3-dimensional (3D) GRE imaging is still preferred over 2D SE because of superior lesion detection with thin-slice volumetric acquisition. 31,32,34 Assessing for BM at Progression Progressive systemic disease When patients with mRCC show progressive disease systemically without neurologic symptoms, it is a matter of debate whether brain imaging is required. Most patients who have mRCC with BMs also have distant metastases; BMs are rarely found in isolation.…”

“…In patients with mRCC who have CNS symptoms, eg, headache, nausea, vomiting, blurred vision, or focal neurologic deficits, imaging is indicated. MRI with and without administration of a gadolinium‐based contrast agent (GBCA) is preferred to computed tomography (CT) because of its superior soft tissue contrast and increased sensitivity for detecting BMs 1,31,32 . In an emergency setting, CT is usually performed because of its wide availability and rapid accessibility; preferably, CT should be performed with and without an iodine contrast agent 33 …”