Squamous cell carcinomas metastatic to cervical lymph nodes from an unknown head-and-neck mucosal site treated with radiation therapy alone or in combination with neck dissection

Purpose: The present study presents the experience at the University of Flo rida with treatment of patients with squamous cell carcinomas (SCC) metasta tic to cervical lymph nodes from an unknown head-and-neck mucosal (H&NM) si te with radiotherapy (RT) alone or in combination with neck dissection (ND) , Methods and Materials: The study included 126 patients treated with curativ e intent from 1964 to 1997. All patients had follow-up for at least 2 years . No patients were lost to follow-up. Results: Twelve patients (10%) developed SCC in H&NM sites at 0.5 to 10.9 y ears (median, 1.8 years). The rate of developing carcinomas in H&NM sites a t 5 years was 13%, Histologic differentiation significantly affected the ra te of developing carcinomas in H&NM sites in multivariate analysis, Sixteen patients (13%) had persistent nodal disease and 12 patients (10%) develope d recurrent nodal disease at 0.5 to 10.9 years (median, 1.1 years). The nod al control rate at 5 years was 78%. Nodal size, N stage, and planned ND sig nificantly affected the rate of nodal control in multivariate analysis, Nin eteen patients (15%) developed distant metastasis at 0.2-5.1 years (median, 0.9 years). The distant metastases rate at 5 years was 14%. Extracapsular extension and RT dose significantly affected the risk of distant metastases in multivariate analysis, The overall absolute survival rate at 5 years wa s 47%. Extracapsular extension, N stage, RT dose for H&NM sites, and planne d ND significantly affected absolute survival in multivariate analysis. The rate of cause-specific survival at 5 fears was 67%, Extracapsular extensio n, nodal size, N stage, overall treatment time, and planned ND significantl y affected cause-specific survival in multivariate analysis, Eight patients (6%) had severe postoperative complications and 6 patients (5%) had severe late complications. Conclusion: The present study supports the effectiveness of RT in lowering the rate of developing carcinomas in the H&NM sites, (C) 2001 Elsevier Scie nce Inc.