The Role of Radiation Therapy

For the vast majority of patients with a spinal meningioma, surgery is the only treatment needed. Because most of these tumors are benign (WHO Grade 1) and can be removed completely, radiation is generally not a standard part of the initial treatment plan ^[1][2].

However, there are specific situations where your medical team may recommend radiation therapy as an additional tool.

When is Radiation Considered?

Radiation is typically reserved for “complex” cases rather than routine ones. Your doctor might discuss radiation with you if:

• Subtotal Resection: The tumor was attached to a critical nerve or blood vessel, and the surgeon intentionally left a small piece behind to avoid causing permanent damage ^[1][3].
• Recurrence: The tumor has grown back after a previous surgery ^[1].
• Higher Grade: The pathology report shows the tumor is a WHO Grade 2 (atypical) or WHO Grade 3 (malignant), which have a higher risk of returning ^[4][5].
• Inoperable Tumors: The tumor is in a location where surgery is considered too dangerous for your overall health or neurological function ^[1].

The Grade 2 Controversy

There is currently no universal consensus on whether every WHO Grade 2 spinal meningioma needs radiation after surgery. Some studies show that if the surgeon was able to remove the entire tumor, the risk of it coming back is low enough that radiation can be avoided ^[6]. Other experts suggest that because Grade 2 cells are more active, radiation should be considered even after a “clean” surgery to be safe ^[4]. This decision is usually made on a case-by-case basis by a multidisciplinary tumor board.

Protecting the Spinal Cord and Managing Risks

The biggest challenge with radiating the spine is that the spinal cord is extremely sensitive to radiation. Doctors must balance the dose needed to target tumor cells with the tolerance limits of the healthy spinal cord ^[7].

• Radiation Myelopathy: This is a rare but serious complication where radiation damages the spinal cord, potentially causing weakness or numbness months or years after treatment ^[8][9].
• Dose Limits: To prevent this, radiation oncologists use evidence-based, fractionation-specific dose-volume constraints on the amount of radiation the cord receives ^[7].

Radiation can also cause side effects like significant fatigue, skin or pain reactions, a small long-term risk of secondary malignancy, and an increased risk of vertebral fracture in the treated area.

Types of Radiation Therapy

There are two main ways radiation is delivered to the spine:

1. Stereotactic Body Radiation Therapy (SBRT) / Radiosurgery: This technique uses highly focused, high-dose beams to target the tumor with pinpoint accuracy, usually in 1 to 5 sessions ^[10][11]. It is often used for small, well-defined areas of tumor ^[10].
2. Fractionated Radiotherapy: This involves giving much smaller doses of radiation every day for several weeks (usually 25–30 sessions) ^[7]. This approach is often chosen based on geometry, tumor size, or if the cord is already showing signs of pressure or swelling ^[10][8].

By spreading the dose out over many days, normal tissues have time to recover, which helps clinicians meet spinal-cord safety constraints ^[7]. Your radiation oncologist will use a combination of MRI and CT scans to create a 3D map of your spine to ensure the beams are as precise as possible ^[12].