Quantitative Analysis of Extracapsular Extension of Metastatic Lymph Nodes and its Significance in Radiotherapy Planning in Head and Neck Squamous Cell Carcinoma

The incidence of ECE is associated with larger LN size. However, ECE is found in a substantial number of LN with a diameter of < 10 mm. The use of 10-mm CTV margins around the gross tumor volume seems appropriate to account for ECE in radiotherapy planning of head and neck cancer.