Neck dissection field and lymph node density predict prognosis in patients with oral cavity cancer and pathological node metastases treated with adjuvant therapy

Pathological lymph node metastases (pN+) are an established prognostic factor in oral cavity squamous cell carcinoma (OSCC). We retrospectively examined the prognostic significance of lymph node (LN) density in pN+ OSCC patients who underwent neck dissection (ND) and postoperative adjuvant therapy. We examined 309 pN+ patients who underwent levels I-III ND and 148 pN+ patients treated with levels I-V ND. The 5-year control and survival rates served as the main outcome measures. The 5-year rates for patients treated with levels I-III and I-V NDs were as follows: local control, 79%, 74% (p=0.0630); neck control, 81%, 68% (p=0.0014); distant metastasis, 21%, 36% (p=0.0003); disease-free survival (DFS), 59%, 43% (p=0.0001); disease-specific survival (DSS), 66%, 46% (p