Vol.98 No.10 contentsPRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 98 No. 10 October 2005
Two Cases of Olfactory Neuroblastoma
Megumi Kikuchi, Hiroshi Tsubota, Atsushi Harimaya,
Nobuhiko Seki, Katsufumi Hoki and Tetsuo Himi
(Sapporo Medical University)
Olfactory neuroblastoma is a relatively rare malignant neoplasm, believed to arise from the epithelium of the upper nasal cavity. Approximately 300 cases of olfactory neuroblastoma have been described in the medical literature since the first case report by Berger and associates in 1924 introduced the tumor entity. To prevent the tumor invading the skull base, a combined transnasal and endocranial approach is essential. In general, the combination of surgery and radiotherapy seems to be the optimum approach to treatment, and its survival at five years is about 65％. We have experienced two cases of olfactory neuroblastoma and report them here with some considerations.
Case 1 was a 60-year-old female. She presented with nasal obstruction and magnetic resonance imaging revealed a mass limited to the nasal cavity. She was treated with partial maxillectomy by lateral rhinotomy and followed by postoperative irradiation. She is still alive with no evidence of local recurrence or metastasis about three years after the initial treatments.
Case 2 was a 35-year-old male. He experienced left upper neck swelling and computed tomography revealed a submandibular tumor. Tumor resection was performed, and histopathological diagnosis was myoepithelioma. After that he presented with nasal bleeding and left upper neck tumor, and magnetic resonance imaging revealed a mass in the nasal cavity that infiltrated intracranially and a swelling lymph node in the left upper neck. Biopsy was performed and those tumors were diagnosed as olfactory neuroblastoma. After reexamination, the submandibular tumor was histopathologically same as above. En bloc resection by craniofacial surgery and the left neck dissection was carried out with subsequent radiotherapy. The patient shows no recurrence or metastasis during a two-year follow-up.
In both cases, we reffered to Hyams' classification to determine treatment planning and found it useful.
Key words : olfactory neuroblastoma, nasal cavity, skull base, transnasal and endocranial approach, Hyams' classification