The prognostic value of location and size change of pathological lymph nodes evaluated on CT-scan following radiotherapy in head and neck cancer

BACKGROUND: Overall survival after chemo-radiotherapy (CRT) for head and neck cancer ranges between 50 and 60% after 5 year of follow-up. Local and/or regional recurrence is the most frequent form of therapy failure. The aim of this study is to investigate whether the initial location and size change of pathological lymph nodes as evaluated on Computed Tomography (CT) studies can help predict outcome. METHODS: One hundred eighty-three patients with lymph node-positive head and neck cancer were treated with radiotherapy (RT) or CRT. CT studies pre- and post-treatment were reviewed for lymph node size and location. Data were correlated with local control, regional control, metastasis free survival, disease free survival and overall survival. RESULTS: Regarding the risk for distant metastasis, a significant influence was seen for the location of the pathological lymph nodes. The metastatic risk increases when levels IV-V are affected rather than levels I-III. A similar observation is seen for levels VI-VII. Regional control improves with decreasing lymph node diameter and volume as evaluated on CT. CONCLUSIONS: Both location and size change of pathological lymph nodes are of prognostic value after CRT for head and neck cancer.