Lymph node metastasis in T4 maxillary sinus squamous cell carcinoma: Incidence and treatment outcome

Background: The purpose of this study was to evaluate the incidence of lymph node metastasis among patients with T4 maxillary sinus squamous cell carcinoma (MS-SCC) as well as the delayed metastasis rate and the treatment outcome for untreated N0 neck in patients with T4 MS-SCC. Methods: Consecutive series of all patients (n = 128) with previously untreated T4 maxillary sinus SCC between 2006 and 2007 were obtained from 28 institutions belonging to or cooperating in the Head and Neck Cancer Study Group of the Japan Clinical Oncology Group. Results: Of the 128 patients, 28 (21.9 %) had lymph node metastasis, and six patients (4.7 %) had distant metastasis at diagnosis. Among the 111 patients who were treated with curative intent, 98 had clinically N0 neck disease and did not receive prophylactic neck irradiation. A total of 11 patients (11.2 %) subsequently developed evidence of lymph node metastasis, of whom eight were among the 83 patients with an N0 neck and had not received elective neck treatment. There were 15 patients who received an elective neck dissection as part of the initial treatment, of whom three had pathologically positive for lymph node metastases. Of 11 patients, six patients with nonlateral retropharyngeal lymph node metastasis without primary or distant disease were successfully salvaged. Conclusions: This study identified the incidence of lymph node metastasis among patients with T4 MS-SCC as well as the delayed metastasis rate and the treatment outcome for untreated N0 neck in patients with T4 MS-SCC. These results will be of assistance in selecting treatment strategy for T4 MS-SCC in the future.