Association between end-induction response according to the revised International Neuroblastoma Response Criteria (INRC) and outcome in high-risk neuroblastoma patients.

BACKGROUND: The 1993 International Neuroblastoma Response Criteria (INRC) were revised in 2017 to include modern functional imaging studies and methods for quantifying disease in bone marrow. We hypothesized the 2017 INRC would enable more precise assessment of response to treatment and provide superior prognostic information compared with the 1993 criteria. METHODS: High-risk (HR) neuroblastoma patients from two institutions in Chicago diagnosed between 2006 and 2016 were identified. Patients were assessed post induction chemotherapy via the 1993 and 2017 INRC and classified as responder (≥ mixed response [MXR] or ≥ minor response [MR], respectively) or nonresponder (< MXR or < MR). Event-free survival (EFS) and overall survival (OS) for responders versus nonresponders were determined from end induction and stratified by Cox regression. Patients with progressive disease at end induction were eliminated from the EFS analyses but included in the OS analysis. RESULTS: The 1993 criteria classified 52 of the 60 HR patients as responders, whereas 54 responders were identified using the 2017 criteria (Spearman correlation r = 0.82, P < 0.001). No statistically significant difference in EFS was observed for responders versus nonresponders using either criteria (P = 0.48 and P = 0.08). However, superior OS was observed for responders (P = 0.01) using either criteria. Both criteria were sensitive in identifying responders among those with good outcomes. The specificity to identify nonresponders among those with poor outcomes was poor. CONCLUSIONS: In HR neuroblastoma, end-induction response defined by the 1993 or 2017 INRC is associated with survival. Larger cohorts are needed to determine if the 2017 INRC provides more precise prognostication.

Historical time to disease progression and progression-free survival in patients with recurrent/refractory neuroblastoma treated in the modern era on Children's Oncology Group early-phase trials.

BACKGROUND: Early-phase trials in patients with recurrent neuroblastoma historically used an objective "response" of measureable disease (Response Evaluation Criteria In Solid Tumors [RECIST], without bone/bone marrow assessment) to select agents for further study. Historical cohorts may be small and potentially biased; to the authors' knowledge, disease recurrence studies from international registries are outdated. Using a large recent cohort of patients with recurrent/refractory neuroblastoma from Children's Oncology Group (COG) modern-era early-phase trials, the authors determined outcome and quantified parameters for designing future studies. METHODS: The first early-phase COG trial enrollment (sequential) of 383 distinct patients with recurrent/refractory neuroblastoma on 23 phase 1, 3 phase 1/2, and 9 phase 2 trials (August 2002 to January 2014) was analyzed for progression-free survival (PFS), overall survival (OS), and time to disease progression (TTP). Planned frontline therapy for patients with high-risk neuroblastoma included hematopoietic stem cell transplantation (approximately two-thirds of patients underwent ≥1 hematopoietic stem cell transplantation); 13.2% of patients received dinutuximab. RESULTS: From the time of the patient's first early-phase trial enrollment (383 patients), the 1-year and 4-year PFS rates ( ± standard error) were 21% ± 2% and 6% ± 1%, respectively, whereas the 1-year and 4-year OS rates were 57% ± 3% and 20% ± 2%, respectively. The median TTP was 58 days (interquartile range, 31-183 days [350 patients]); the median follow-up was 25.3 months (33 patients were found to be without disease recurrence/progression). The median time from diagnosis to first disease recurrence/progression was 18.7 months (range, 1.4-64.8 months) (176 patients). MYCN amplification and 11q loss of heterozygosity were prognostic of worse PFS and OS (P = .003 and P<.0001, respectively, and P = .02 and P = .03, respectively) after early-phase trial enrollment. CONCLUSIONS: This recent COG cohort of patients with recurrent/refractory neuroblastoma is inclusive and representative. To the authors' knowledge, the current study is the first meta-analysis of PFS, TTP, and OS within the context of modern therapy. These results will inform the design of future phase 2 studies by providing a) historical context during the search for more effective agents; and, b) factors prognostic of PFS and OS after disease recurrence to stratify randomization. Cancer 2017;123:4914-23. © 2017 American Cancer Society.