Treatment strategy for patients with esthesioneuroblastoma and long-term outcomes

Abstract
The study objective is to summarize clinical experience in the treatment of esthesioneuroblastoma (ENB) accumulated by specials at N.N. Blokhin National Medical Research Center of Oncology.Materials and methods. We analyzed the data of 115 ENB patients who had undergone treatment between 1965 and 2019.Results. The 15-year overall survival rate was 1.2–1.7 times higher in patients receiving comprehensive treatment (47.7 ± 11.3 %) than in those receiving other types of therapy. In addition to that, comprehensive treatment ensured the highest rates of 3-year, 5-year, and 10-year relapse-free survival (49.3 ± 11.8 %), as well as the longest median survival (7.2 years). Chemoradiotherapy was effective in 34.8 % of patients with locally advanced ENB, while in 9 out of 45 patients (20.0 %), it resulted in partial response, which suggest that such treatment can control aggressive disease course and increase survival. Surgical treatment (alone or in combination with chemotherapy and radiotherapy) was indicated for 64 patients. However, only in 43 of them (67.1 %), it was performed as originally planned. Five patients (7.8 %) had partially radical surgeries and sixteen patients (25.1 %) had non-radical surgeries.Conclusion. The most effective treatment strategy for locally advanced ENB is a combination of surgery, chemotherapy, and radiotherapy. Chemoradiotherapy at the first stage followed by surgery was found to be an optimal treatment scheme. Tumor sensitivity to chemo- and radiotherapy affects both short-term and long-term treatment outcomes. Partially radical surgeries for locally advanced ENB are acceptable if conservative treatment is planned after operation. Treatment strategy should depend on the tumor spread (stage), grade, and proliferative activity, as well as patient’s age, somatic status, and comorbidities. Multivariate analysis has demonstrated that none of treatment methods decrease survival. The most significant factors negatively affecting the prognosis were as follows: T3–4 tumor, involvement of regional lymph nodes before treatment initiation, distant metastasis, grade IV tumor, and Ki-67 index >21 %.