Background: Tumors in the nasal cavity and paranasal sinus are difficult to treat with radiotherapy. Usually, in addition to a two- or three-field photon technique, an interorbital electron field is required. This may result, however, in severe over- or underdosage, the latter being especially detrimental when occurring in the main tumor bulk.
Methods and results: We present a conformal three-dimensional treatment technique that provides sufficient interorbital dose with photons only while sparing the eyes, optic nerves and chiasm, and may be considered for selected tumors in this region.