Targeted intervention to improve the quality of head and neck radiotherapy treatment planning in the Netherlands: short and long-term impact.

Despite many years of HNC IMRT experience, initial treatment plans showed surprisingly large variations. The simple targeted intervention used in this analysis improved OAR sparing and its impact was durable, however fairly large dose differences still continue to exist. Additional work is needed to understand these variations and to minimize them. A national radiation oncology platform can be instrumental for developing and maintaining high quality planning protocols.