Treatment of maxillary sinus carcinoma - A comparison of the 1997 and 1977American Joint Committee on Cancer staging systems

BACKGROUND. This study was conducted to assess the effectiveness of the 199 7 American Joint Committee on Cancer (AJCC) staging system to predict survi val and local control of patients with maxillary sinus carcinoma and to ide ntify significant factors for overall survival, local control, and distant metastases in patients with these tumors. METHODS. Ninety-seven patients with maxillary sinus carcinoma were treated with radiotherapy at Stanford University and the University of California, San Francisco between 1959-1996. The histologic type of carcinoma among the 97 patients were: 58 squamous cell carcinomas, 4 adenocarcinomas, 16 undif ferentiated carcinomas, and 19 adenoid cystic carcinomas. All patients were restaged clinically according to the 1977 and 1997 AJCC staging systems. T he T classification of the tumors of the patients was as follows: 8 with T2 , 18 with T3, and 71 with T4 according to the 1977 system and 8 with T2, 36 with T3, and 53 with T4 according to the 1997 system. Eleven patients had lymph node involvement at diagnosis. Thirty-six patients were treated with radiotherapy alone and 61 received a combination of surgical and radiation treatments. The median follow-up for surviving patients was 78 months. RESULTS. The 5-year and 10-year actuarial survival rates for all patients w ere 34% and 31%, respectively. The 5-year survival estimate by the 1977 AJC C system (P = 0.06) was 75% for Stage II, 19% for Stage III, and 34% for St age TV and by the 1997 AJCC system (P = 0.006) was 75% for Stage II, 37% fo r Stage III, and 28% for Stage IV. Significant prognostic factors for survi val by multivariate analysis included age (favoring younger age, P < 0.001) , 1997 T classification (favoring T2-3, P = 0.001), lymph node involvement at diagnosis (favoring NO, P = 0.002), treatment modality of the primary tu mor site (favoring surgery and radiotherapy, P = 0.009), and gender (favori ng female patients, P = 0.04), The overall radiation time was of borderline significance (favoring shorter time, P = 0.06). The actuarial 5-year local control rate was 43%. By the 1977 AJCC system (P = 0.78) it was 62% with T 2, 36% with T3, and 45% with T4 and using the 1997 AJCC system (P = 0.29) i t was 62% with T2, 53% with T3, and 36% with T4. The only significant progn ostic factor for local control for all patients by multivariate analysis wa s local therapy, favoring surgery and radiotherapy over radiotherapy alone (P < 0.001). For patients treated with surgery, pathologic margin status co rrelated with local control (P = 0.007) and for patients treated with radia tion alone, higher tumor dose (P = 0.007) and shorter overall treatment tim e (P = 0.04) were associated with fewer local recurrences. The 5-year estim ate of freedom from distant metastases was 66%. The 1997 T classification, N classification, and lymph node recurrence were adverse prognostic factors for distant metastases on multivariate analysis. There were 22 complicatio ns in 16 patients, representing a 30% actuarial risk of developing late com plications at 10 years. CONCLUSIONS. The 1997 AJCC staging system was found to be superior to the 1 977 AJCC staging system in predicting both survival and local control in th is patient population. Combined surgical and radiation treatment to the pri mary tumor yielded higher survival and local control than radiotherapy alon e. Other significant prognostic factors for survival were patient age, gend er, and lymph node (N) classification. Prolonged overall radiation time was associated with poorer survival and local control. Late severe toxicity fr om the treatment of these tumors was a significant problem in long term sur vivors. Improved radiotherapy techniques should lead to decreased injury to the surrounding normal tissues. (C) 1999 American Cancer Society.