====== Cerebellar metastases radiosurgery ======

{{rss>https://pubmed.ncbi.nlm.nih.gov/rss/search/12UQ-02Q1yB7OJNUqOwcXXeVBFFB4QwIwkPSpCgqp7Vlo2mg3D/?limit=15&utm_campaign=pubmed-2&fc=20230508161443}}


===== 🔬 Clinical Context =====
  * [[Cerebellar metastases]] represent **20–30%** of all brain metastases.
  * Frequent primaries: 
    * Lung
    * Breast
    * Melanoma
    * Renal cell carcinoma
  * Critical concerns:
    * Brainstem compression
    * Fourth ventricle involvement
    * Risk of obstructive hydrocephalus or herniation

===== 🎯 Indications for Radiosurgery =====
  * Lesion size **<3–4 cm** or volume **<10–15 cc**
  * **Oligometastatic disease** (≤4 lesions)
  * Good functional status (**KPS ≥70**)
  * Controlled systemic disease
  * Life expectancy **>3–6 months**

===== 💡 Advantages =====
  * Minimally invasive
  * High local control (**85–95%** at 6–12 months)
  * Outpatient or short-stay procedure
  * Defers or avoids WBRT
  * Preserves neurocognition
  * Often avoids surgical resection

===== ⚙️ Technical Considerations =====
  * Technologies:
    * Gamma Knife (GKRS)
    * CyberKnife
    * LINAC-based SRS
    * Hypofractionated SRS (hfSRS)
  * Dose example:
    * **18–24 Gy** in 1 fraction (adapted to size/location)
  * Frameless or frame-based delivery

===== 🧠 Risks and Follow-Up =====
  * Complications:
    * Radiation necrosis (5–15%)
    * Cerebellar edema → treat with corticosteroids
  * Lesions near brainstem → consider hypofractionation
  * Surveillance:
    * MRI brain with contrast:
      * 1st control at 2–3 months
      * Then every 2–3 months

===== 🧾 Evidence Summary =====
  * Retrospective studies show:
    * High local control
    * Comparable to surgery for small, asymptomatic lesions
  * Preferred approach for large/symptomatic lesions:
    * Surgical resection + adjuvant SRS to cavity




===== Upfront Frameless Hypofractionated Gamma Knife Radiosurgery =====
[[Upfront Frameless Hypofractionated Gamma Knife Radiosurgery]]