2025 Poster Presentations
P316: TREATMENT MODALITIES AND OUTCOMES IN EARLY-STAGE OLFACTORY NEUROBLASTOMA: EXTENT OF RESECTION AND POSTOPERATIVE RADIOTHERAPY
Minju Kim, MD1; Sung Woo Cho, MD, PhD2; Chae-Seo Rhee, MD, PhD2; Tae-Bin Won, MD, PhD3; 1National Medical Center, Seoul, Korea; 2Seoul National University Bundang Hospital; 3Seoul National University Hospital, Seoul, Korea
Background: Olfactory neuroblastoma (ONB), a rare sinonasal malignancy, is conventionally treated with surgical excision including craniofacial resection, and often supplemented with adjuvant radiotherapy, particularly in advanced stages. Despite this, challenges persist in formulating optimal treatment strategies for early-stage ONB.
Methods: 41 Patients diagnosed with ONB, whose Dulguerov stage was 3 or below, without any overt orbital invasion or cervical lymph node metastasis, in two tertiary hospitals from 1992 to 2023 were reviewed.
Results: There was no significant difference in disease-free survival according to treatment modality (definitive RT vs surgery-based treatment, log-rank p=0.731), extent of resection (mass resection vs craniofacial resection, log-rank p=0.262), adjuvant RT (with vs without adjuvant RT, log-rank p=0.37, and Hyams grade (low vs high, log-rank p=0.443). However, among the patients who underwent resection only, disease-free survival tended to be higher for those who had adjuvant RT (log-rank p=0.089) with significantly higher local free survival (log-rank p=0.009). Among those patients who underwent craniofacial resection, none showed local recurrence, and there was no significant difference in disease-free survival according to adjuvant RT (log-rank p=0.370)
Conclusions: In early-stage ONB, overall survival seems favorable regardless of the chosen treatment modality, but the role of definitive RT remains uncertain. Adjuvant radiotherapy has been shown to mitigate local recurrences in patients who underwent mass excision alone, yet its efficacy remains uncertain for patients who underwent craniofacial resection. Further studies with larger patient cohorts are warranted.