40 is the new 50.
One approach to de-escalating head and neck radiation is to reduce the dose and volumes of elective neck coverage. In this phase 2 study, 75 patients receiving definitive radiation for oropharyngeal (71%) and laryngeal (29%) cancers had dose and volume de-escalated treatment to the elective neck. Elective nodal regions included bilateral level II for oropharynx primaries and bilateral II-III for larynx primaries (T1-2N0 excluded). Any involved level and the adjacent level, and any level containing a radiographically suspicious node were also included. These elective sites were treated to 40 Gy / 20. The primary tumor and gross nodes were sequentially boosted to 70 Gy in 15 additional fractions, while suspicious nodes and the high risk region around the primary simultaneously received a total of 64 Gy. There were zero isolated nodal failures in the low or no-dose neck levels. Five of 7 nodal recurrences were within the 70 Gy volume. One nodal failure occurred in a low-dose and no-dose region, respectively, in the setting of other disease progression. TBL: Isolated failures in the elective neck are uncommon even with reduced dose and volume coverage. | Sher, Int J Radiat Oncol Biol Phys 2020