The impact of neck lymph node volumetric status on local control of the primary tumour (LTC) in radiotherapy for oral cavity and oropharyngeal cancer

The study analyses the impact of volumetric nodal involvement (total nodal volume – TNV) on local control of the primary tumour (LTC) in radiotherapy for oral cavity and oropharyngeal cancer. The results show a significant decrease of the LTC (within a constant GTV) by about 10–20%, when the TNV increases from 10 to 40 cm3. It suggests delivering an extra boost dose of 3–4 extra fractions of 2.0 Gy fractions to the primary tumour in the case of nodal involvement (initial total nodal volume).