Zhenzhen Yin

Radiation, Cancer Institute (Hospital), Chinese Academy of Medical Sciences, Peking union     Medical College.

Objective: There is currently no consensus on standardized treatment strategy for esthesioneuroblastoma (ENB) due to its relatively low incidence and biological variability. The purpose of this study is to characterize the clinical features and the long term treatment outcomes of ENB.

Method:Between Jun. 1979 and Nov. 2014, 113 patients treated for localized ENB at our institution were retrospectively analyzed. According the Kadish stage classification, the distribution was 1% (1 patient) stage A, 20% (23 patients) stage B, 79% (89 patients) stage C. 25% (28cases) were N+ disease at initial presentation. Since chemotherapy alone do not be considered as first line therapy, unless concurrent with radiotherapy (for 34 patients) or in neoadjuvant or adjuvant settings (for 44 patients). The treatment modality of ENB included surgery + postoperative radiotherapy ± chemotherapy (51 patients), preoperative radiotherapy + surgery ± chemotherapy (11 patients), radiotherapy ± chemotherapy (47 patients), surgery ± chemotherapy (3 patient). Only one patient who abandoned surgery and radiotherapy were treated with chemotherapy alone.

Result:The 5-year overall survival (OS) and disease-free survival (DFS) for patient with stage A/B were 82% and 71%, respectively, compared with 61% and 49% in Stage C (P=0.036 for OS, P=0.025 for DFS). Neck metastasis was associated with inferior OS and distant metastasis-free survival (DMFS) (the 5-year OS 72% vs. 46%, P=0.005; 5-year DFS 64% vs. 26%, P=0.002). According to different treatment modalities, 3 patients treated with surgery ± chemotherapy all developed local recurrence, none survived longer than 4 years. The 5-year OS, DMFS and local relapse-free survival was 91%, 91% and 91% in patients treated with preoperative radiotherapy + surgery ± chemotherapy; 79%, 79% and 82% in patients treated with surgery + post-operative radiotherapy ± chemotherapy; 50%, 46% and 63% in patients treated with radiotherapy ± chemotherapy. Selection biases were existed within different treatment modalities, 40% of cases in radiotherapy group were N+ disease, while only 13% in surgery combined radiotherapy group.

Conclusion:Surgery combined radiotherapy showed favorable treatment outcomes in patients with ENB, especially preoperative radiotherapy plus surgery indicated best survival. Node metastasis and Kadish C stage showed inferior survival outcome.

Key Words: Esthesioneuroblastoma, Treatment outcome