Anti-GD2 immunotherapy in adults with high-risk neuroblastoma (HR-NB): The Memorial Sloan Kettering Cancer Center (MSKCC) experience.

Abstract

10550 Background: The diagnosis of NB in adulthood is rare and little is known about its biology and clinical course. There is no established therapy for adult NB. Anti-GD2 immunotherapy is now standard in children with HR-NB but its use has not been reported in adults. Methods: After obtaining IRB waiver, records of all patients with adult-onset (≥18 years) NB seen at MSKCC between 1983 and 2015 were reviewed. Overall survival (OS) was tested by log-rank test. Cox-regression was used for multivariate analysis. Results: The subjects were 42 adults (median: 25; range18-71 years); 23 male and 19 female. Five, 1, 1 and 35 patients had INSS stage 1, 2, 3 and 4 disease, respectively. Genetic abnormalities included somatic ATRX (59%) and ALK mutations (43%) but not MYCN-amplification. 16 patients remain alive at a median follow-up of 5.3 years. OS for non-stage 4 patients was superior to stage 4 (median survival 14.6 vs 5.3 years; p < 0.05). However 5/7 patients with < stage 4 NB progressed to stage 4. Among 35 stage 4 patients, 4 achieved complete remission (CR) after induction chemotherapy and surgery, 11 underwent autologous stem cell transplant (ASCT) and 15 received multiple cycles of anti-GD2 antibodies 3F8 or hu3F8 without complications. In univariate analysis, patients ≤ 29 years old (n = 24) at diagnosis, those achieving CR, and those receiving anti-GD2 antibodies had superior OS (p < 0.05 for each). ASCT was not beneficial (p = 0.3 for ASCT vs no ASCT). For stage 4 patients, anti-GD2 immunotherapy was associated with favorable OS in multivariate analysis (95% CI of anti-GD2 antibody: 1.270 to 7.990). Conclusions: Adult-onset stage 4 NB demonstrates a high incidence of somatic mutations and is only partially chemosensitive. However, 3F8/hu3F8-based anti-GD2 immunotherapy appears to improve long-term survival and is well tolerated.