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Possibilities and limitations of endoscopic management of nasal and paranasal sinus malignancies.

Over the last decade, the use of rigid endoscopes in surgery of tumorous lesions of the nose, paranasal sinuses, nasopharynx and anterior skull base has extended and diversified. Endoscopic surgical approaches for malignant lesions are very controversially discussed as of today, yet. From 1989-1999 we have treated 43 patients with invasive/destructive tumors of the paranasal sinuses and the anterior skull base strictly endoscopically, transnasally. These included 5 patients with juvenile angiofibromas and 36 patients with various malignant tumors, one with a large invasive macroadenoma of the pituitary and one case of a craniopharyngeoma. The age range was 3 months to 82 years. Whereas the very first patients were approached endoscopically in a palliative intention, we have started endoscopic surgery for selected malignancies with curative intention in the last years. Histologically, patients with various carcinoma differentiation were operated (n = 18), as well as patients with malignant melanoma (n = 5), esthesioneuroblastoma (n = 8), clivus chordoma (n = 3), immature teratoma (n = 1) and leiomyosarcoma (n = 1). Our first results appear to indicate, that outcome is at least equal to standard external approaches, however with excellent functional terms and significantly better overall quality of life. The limitations result from the anatomical spread of the tumor, when extensive infiltration of orbit, dura/brain and other vital structures exist. However, in experienced hands, endoscopic surgery in this region can be rather radical, bone and even dura of the anterior skull base can be resected as can the periorbit, and all structures reconstructed in the same session. Endoscopic techniques lend themselves very well to cooperation with neighbouring specialities like neurosurgery. In individual cases, gamma-knife therapy has proven an extremely helpful adjunctive. With this combined approach, all 8 patients with esthesioneuroblastoma are alive and free of disease with a mean observation time of 37.2 months. We will therefore continue to use this procedure in selected cases as a reliable alternative to external approaches in the future. However we recommend, that these techniques are only applied at centers, where all other surgical approaches can be performed, should need for this arise.