Comparing the role of different treatment modalities in locoregionally advanced olfactory neuroblastoma: The 20-year clinical experience of a single institution.

Abstract

e18055 Background: There are few studies on different treatment modalities, especially systemic chemotherapy (CT) for locoregionally advanced olfactory neuroblastoma (LA ONB) with only a few small-sample studies reported. We retrospectively analyzed the treatment patterns and explored the factors affecting the prognosis of patients with LA ONB at our center over the past 20 years in the present study. Methods: LA ONB patients from 2000 to 2020 at our center were collected retrospectively. The entire cohort was divided into combined systemic and local therapy (CSLT) vs. local therapy (LT) groups (grouping method 1), and the same cohort was divided into neoadjuvant chemotherapy (NAC) vs. non-NAC groups (grouping method 2). CSLT group included patients treated with CT + LT. LT group included patients treated with surgery (SG), radiotherapy (RT), concurrent chemoradiotherapy (CCRT), or any combination of the above methods. LT group was further divided into mono-modality local therapy (MOLT) group and multi-modality local therapy (MULT) group. MOLT group included patients treated with RT alone or SG alone. MULT group included patients treated with SG + RT/CCRT, or CCRT alone. NAC group included patients treated with NAC + LT ± adjuvant chemotherapy (ADC). Non-NAC group included patients who received LT ± ADC. Results: A total of 111 patients with LA ONB were included. The median age was 40 (range, 10–82) years old. The median follow-up duration for the entire cohort was 80.2 (range, 2.1-254.9) months, while 88.5 (range, 4.0-240.7) months for the CSLT group, 77.2 (range, 2.1-254.9) months for the LT group, 86.0 (range, 4.0-240.7) months for the NAC group, and 78.7 (range, 2.1-254.9) months for the non-NAC group. Thirty-five patients (31.5%) died, among which 30 patients died of tumor progression, 3 patients died of other diseases, and 2 patients’ causes of death were not available. The estimated 5-year overall survival (OS), progression-free survival (PFS), local recurrence-free survival (LRFS) and distant metastasis-free survival (DMFS) rates for the entire cohort (n = 111) were 70.2%, 53.1%, 73.6%, and 74.1%, respectively. The estimated 10-year OS, PFS, LRFS, and DMFS rates were 61.3%, 37.7%, 60.1%, and 68.0%, respectively. In univariate analysis, patients treated with NAC (n = 43) had significantly better overall survival (OS) compared with those without NAC (n = 68) ( P = 0.041). Patients in MULT group (n = 45) had significantly improved OS ( P = 0.004) and PFS ( P = 0.003) compared with those in MOLT group (n = 15). Multivariate analysis identified NAC and CSLT (n = 51) were independent prognostic factors for superior OS ( P = 0.020; P = 0.046). Conclusions: Our study suggested that CSLT, especially a combination of NAC and LT, improved the survival of patients with LA ONB. Multiple treatment modalities yielded better PFS and OS compared to single modality treatment.