[Radiotherapy of olfactory neuroblastoma--report of 5 patients].

Olfactory neuroblastoma is a rare tumor arising from the olfactory mucosal epithelium. 5 patients with this tumor were treated in our hospital from 1978 to 1982. The youngest patient was 3 years old and the eldest was 66. The clinical symptoms were nasal stuffiness, rhinorrhea, epistaxis and vascular polypoid mass in the nasal cavity. According to the staging system proposed by Kadish et al, the five patients in this series were 3 stage A and 2 stage C patients. Treatment consisted of radiotherapy, surgery or combination of radiotherapy and surgery. Our data indicate that the olfactory neuroblastoma is a radiosensitive tumor with the prognosis favorable in the stages A and B patients as treated by these three modalities. Two stage A patients are alive for more than 5 years. One of them was treated by radiotherapy alone, the other by combination of surgery and radiation. The third stage A patient as treated by radiotherapy alone has survived more than 3 years. One stage C patient, treated by combination of radiation and surgery, is still alive for more than 3 years. The other stage C patient, treated by radiotherapy alone, had survived for only 7 months after the treatment. The radiation dose varies with the extent of invasion. In stages A and B lesions, a dose of 4,500-5,500 rad in 5 weeks may be reasonable but in stage C, a dose of 6,000-6,500 rad in 7 weeks should be given. The authors agree to the prognostic equation proposed by Homzie et al. It may be possible to predict the tumor control or recurrence after a period of 3 years which gives an accuracy rate of 87%.