Which Role for Radiation Therapy in Ethmoid Cancer? A Retrospective Analysis of 84 Cases from a Single Institution

Abstract

To define the results of radiotherapy for the treatment of ethmoid carcinoma in a large, retrospective, substantially unselected series from a single institution. A relatively large series of 84 consecutive patients treated at our Institution over a 30-year period (1970-2000) was retrospectively analyzed. Sixteen more patients treated in the same period were affected by a relapse of disease at presentation and were therefore excluded from the analysis. Most of the patients had T3 or T4 disease (76%), and half of them had undifferentiated (G3-G4) tumors. Radical surgery preceded radiotherapy in 60 patients, the remaining had only biopsy or incomplete surgery. Average ICRU dose varied according to the extent of postsurgical residual disease. The 5-year actuarial overall survival of the entire series was 48.6%, 5-year disease-specific survival 58%, and 5-year relapse-free survival 54.6%. Overall, disease-specific and relapse-free survival were significantly better (logrank test) for early stage patients (T1-T2) and for those with low-grade disease; relapse-free and disease-specific survival were also significantly (or almost significantly) better for patients who had radical surgery and for those with less extended postsurgical residue. Patients treated with radiotherapy after biopsy only or grossly incomplete surgery had 5-year relapse-free, disease-specific and overall survival of 22%, 42% and 37%, respectively. Higher cumulative doses (>60 Gy) were related to a not significantly lower recurrence probability in patients with micro- or macroscopic residual disease after surgery (54% vs 62%). Multivariate analysis (Cox model) showed that only T stage and grading were independent prognostic factors for overall and disease-specific survival, whereas the prognostic impact of radical surgery was limited to relapse-free survival. Radical radiation therapy alone is able to cure about 25% of the unfavorably selected cases, after biopsy only or partial surgery. Radical surgery is associated with better relapse-free survival rates, but the contribution of postoperative radiotherapy to the primary treatment of these patients cannot be eliminated.