Radiation Therapy of Maxillary Sinus Cancer

상악동암의 방사선 치료

Purpose : Maxillary sinus cancers usually are locally advanced and involve the structures around sinus. It is uncommon for this cancer to spread to the regional lymph-nodes. For this reason, local control is of paramount important for cure. A policy of combined treatment is generally accepted as the most effective means of enhancing cure rartes. This paper reports our experience of a retrospective study of 31 Patients treated with radiation therapy alone and combination therapy of surgery and radiation. Materials and Methods: Between July 1974 and January 1992, 47 Patients with maxillary sinus cancers underwent either radiation therpay alone or combination therapy of surgery and radiation. Of these, only 31 patients were eligible for analysis. The distribution of clinical stage by the AJCC system was $26\%$(8/31) for T2 and $74\%$(23/31) for T3 and T4. Eight patients had palpable lymphadenopathy at diagnosis. Primary site was treated by Cobalt-60 radiation therapy using through a $45^{\circ}$ wedge-pair technique. Elective neck irradiation was not routinely given. Of these 8 patients, the six who had clinically involved nodes were treated with definite radiation therapy. The other two patients had received radical neck dissection. The twenty-two patients were treated with radiation alone and 9 patients were treated with combination radiation therapy, The RT alone patients with RT dose less than 60 Gy were 9 and those above 60 Gy were 13. Results : The overall 5 year survival rate was $23.8\%$. The 5 year survival rate by T-stage was $60.5\%$ and $7.9\%$ for T2 and T3,4, respectively. Statistical significance was found by T-stage(p<0.005). The 5 year survival rate by N-stage was $30\%$ for N (-) and $8.3\%$ for N(+), but statistically no significant difference was seen(p${\geq}$0.1). The 5 year survival rate for RT alone and combination RT was $22.5\%$ and $27.4\%$, respectively. The primary local control rate was $65\%$ (20/31). Conclusion : This study did not show significant difference in survival between RT alone and combination RT. There is still much controversy with regard to which treatment is optimum. Improved RT technique and development of multimodality treatment are essential to improve the local control and the survival rate in patients with advanced maxillary sinus cancer.