Microvessel density predicts the radiosensitivity of metastatic head and neck squamous cell carcinoma in cervical lymph nodes

Cervical lymph node metastasis is the most common recurrence pattern of hea d and neck squamous cell carcinoma (HNSCC), and it is usually treated with radiation therapy and/or neck dissection. There has long been a desire for markers useful in predicting radiosensitivity to enable assignment of patie nts with recurrent head and neck cancer to clinical trials to improve their survival rates and quality of life. A total of 43 cases of HNSCC treated w ith whole or elective neck irradiation (total dose, 26-70 Gy; median, 60 Gy ) for recurrent metastatic SCC in neck lymph nodes after neck dissection be tween 1992 and 1999 were the subject of this study. The relationship betwee n radiosensitivity and clinicopathological and histopathological factors, i ncluding the Ki-67-labeling index for cell proliferation, p53 immunoreactiv ity and microvessel density (MVD), in surgical neck lymph node specimens we re investigated by univariate and multivariate analysis. Of the 43 patients , 31 had recurrent tumors in neck lymph nodes after radiotherapy. Univariat e analysis revealed significant associations between radiosensitivity and b oth high grade of keratinization (p=0.033) and low MVD (p=0.004), and margi nally significant associations between radiosensitivity and grade of differ entiation of the cancer in the lymph nodes (p=0.070). Multivariate analysis showed that only MVD had predictive value (p=0.016). Tumors with a high MV D possessed a significantly better neck control rate than tumors with a low MVD (p=0.004) by Kaplan-Meier analysis. MVD can be used as a good predicti ve marker for radiosensitivity of metastatic HNSCCs in cervical lymph nodes after neck dissection.