A large retrospective study from two belgian institutions of 78 patients who underwent minimally invasive endoscopic management for malignant sinonasal tumors from, 1992-1999 is presented. We attempt to assess the results of this less invasive approach. The spectrum of disease included adenocarcinoma, squamous cell carcinoma, olfactory neuroblastoma and other malignant tumors. All patients were treated primarily for cure. 66 patients were operated on by a purely endoscopic technique, while 9 patients had a simultaneous neurosurgical and endoscopic approach, and 3 a limited orbital approach. 16 patients (20.5%) presented with local recurrence, 6 patients (7.7%) sustained distant metastases and 7 patients (9%) presented simultaneous local recurrence and distant metastases. The 2-years and 5-years survival rates of the whole group were respectively 73.1% and 52.3%, while the adenocarcinoma group exhibits a significantly better prognosis than other histological types with 2-years and 5-years survival rates of 89.8% and 63.8%. Patients who could be treated purely endoscopically had a significantly better survival in comparison to patients treated by an external and endoscopic approach. Morbidity was minimal and the local control rate as well as survival rates were comparable to literature data. Endoscopic resection was adequate, providing clear margins and en bloc removal in most cases. Our results encourage us to use this minimally invasive approach in selected cases as a reliable alternative to the systematic use of an exclusively external approach.