What is SFRT?
Spatially fractionated radiation therapy intentionally creates a non-uniform dose inside a tumor: small high-dose 'vertices' (peaks) are arranged in a 3D lattice, separated by lower-dose 'valleys.' This pattern produces a strong tumoricidal and immune-stimulatory effect at the peaks while the lower-dose valleys help limit damage to nearby healthy tissue.
SFRT is sometimes referred to historically as GRID therapy (its 2D predecessor) or LATTICE radiotherapy (the modern 3D variant).
Who SFRT is considered for
- Large, bulky tumors (commonly ≥ 6 cm in greatest dimension)
- Sarcomas and other radioresistant histologies
- Tumors that have not responded to prior radiation
- Select re-irradiation cases where conventional retreatment exceeds tolerance
- Symptomatic, debulking-style palliation when surgery isn't an option
What to expect
SFRT is typically delivered as a single high-dose treatment combined with a follow-on course of conventional fractionated radiation. Each treatment session is painless and outpatient. Because SFRT is highly individualized, the radiation oncologist will walk through whether your case is appropriate and what the expected dose distribution will look like.
Important considerations
SFRT is a specialized technique and is not appropriate for every tumor. The decision to use SFRT is made jointly by radiation oncology, medical physics, and your broader oncology team. If you've been told a tumor is 'too large' or 'radioresistant' elsewhere, ask whether SFRT might be an option for you here.
