Analysis of Factors Affecting Long-Term Treatment Results of Adenoid Cystic Carcinoma of the Nose and Paranasal Sinuses

Abstract

At Akita University Hospital (from 1971 to 1987) and at Chiba University Hospital (from 1983 to 1988), 17 patients with adenoid cystic carcinoma of the nose and paranasal sinuses were treated by en bloc tumor resection followed by primary reconstruction of the maxilla. Pre- and post-operative radiation was combined in 5 and 6 patients, respectively. Ten-year cancer-free survival rates were 59.3% in the 12 patients with maxillary sinus tumors and 50% in the 4 patients with nasal tumors. One patient with a sphenoid sinus tumor died within 5 years. Ten-year cancer-free survival was affected markedly by grade of tumor extension. Among T1NOMO and T2NOMO patients (of which there were 1 and 7, respectively), only 1 died of unrelated causes, and 6 patients survived cancer-free for more than 10 years. However, 4 of the 6 T3NOMO patients died, and the cause of death was distant metastasis in 2, intracranial tumor extension in 1, and unrelated causes in 1. All 3 T4NOMO patients died, 2 due to intracranial tumor extension and 1 of unrelated causes. The cause of death was distant metastasis in 3, local recurrence in 3, 2 of whom had intracranial tumor extension, and unrelated causes in 2. Prevention of distant metastasis and intracranial tumor extension was considered to be crucial for improving treatment results after en bloc tumor resection. Preoperative radiation was thought to decrease incidence of distant metastasis. In 5 patients who had preoperative radiation, 4 survived cancer-free for more than 10 years, and only 1 patient died of unrelated cause. However, of the 6 patients who had postoperative radiation, 2 died of distant metastasis and another 2 died of intracranial tumor extension. Of the 6 patients who did not have radiation therapy, the causes of death were local recurrence in 1, distant metastasis in 1 and unrelated causes in 1. Preoperative radiation in 5 patients showed histopathologically moderate or marked degeneration and necrosis of tumors in all patients. Although the number of patients in this study is too small to allow statistical analysis of the data, our present modality of treatment for adenoid cystic carcinoma of the nose and paranasal sinuses is routine combination of preoperative full dose radiation, en bloc tumor resection and primary reconstruction, including en bloc resection of the cranial base in selected T4 patients.