VMAT (Volumetric-Modulated Arc Therapy)
An advanced form of IMRT delivered in a continuous arc.
VMAT delivers IMRT in continuous arcs, shortening treatment time. Standard at most modern radiation oncology programs.
What this means for you: VMAT shortens daily treatment time but doesn't change clinical outcome dramatically vs IMRT. Both are acceptable modern standards.
What a term means for you depends on your own reports. Ask your treating doctor, or send your reports for a free review.