BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) comprises clinical and radiologic findings with rapid onset and potentially dire consequences. Patients experience hypertension, seizures, headache, visual disturbance, and/or altered mentation. Magnetic resonance imaging reveals edematous changes in the brain (especially in the parietal and occipital lobes). In this report, the authors describe PRES associated with antidisialoganglioside (anti‐G_D2) monoclonal antibody (MoAb) immunotherapy, which is now standard for high‐risk neuroblastoma but has not previously been implicated in PRES.METHODS: Successive clinical trials using the anti‐GD2 MoAb 3F8 (a murine immunoglobulin 3 MoAb specific for GD2) for patients with neuroblastoma involved multiple cycles of standard‐dose 3F8 (SD‐3F8) (20 mg/m2 daily for 5 days per cycle) or 2 cycles of high‐dose 3F8 (HD‐3F8) (80 mg/m2 daily for 5 days per cycle) followed by cycles of SD‐3F8.RESULTS: PRES was diagnosed in 5 of 215 patients (2.3%), including 3 of 160 (1.9%) who received SD‐3F8 and 2 of 55 (3.6%) who received HD‐3F8 (P = .6). All 5 patients had a rapid return to clinical‐radiologic baseline. PRES occurred in 3 of 26 patients (11.5%) whose prior treatment included external‐beam radiotherapy to the brain (2 of 6 patients status‐post total body irradiation and 1 of 20 patients status‐post craniospinal irradiation) compared with 2 of 189 patients (1.1%) who had not received prior brain irradiation (P = .01). Hypertension, which is strongly linked to PRES, reached grade 3 toxicity in 12 of 215 patients (5.6%), including the 5 patients with PRES and 7 patients without PRES.CONCLUSIONS: Patients who receive anti‐GD2 MoAb immunotherapy should be closely monitored for, and undergo urgent treatment or evaluation of, symptoms that may herald PRES (eg, hypertension or headaches). Prior brain irradiation may be a predisposing factor for PRES with this immunotherapy. Cancer 2013;119:2789–2795. © 2013 American Cancer Society.

Entrectinib, a central nervous system (CNS)-penetrant TRK/ROS1 inhibitor, has demonstrated clinical activity in children with NTRK1/2/3 or ROS1 fusion-positive extracranial solid and CNS tumours. We present integrated data of entrectinib in children with NTRK or ROS1 fusion-positive tumours from the STARTRK-NG, TAPISTRY, and STARTRK-2 trials. Efficacy analyses were undertaken on TRK/ROS1 inhibitor-naïve patients aged <18 years with metastatic/locally advanced NTRK1/2/3 or ROS1 fusion-positive extracranial solid or CNS tumours who received ≥1 entrectinib dose and had ≥6 months of follow-up from enrolment. Tumour responses were confirmed by blinded independent central review (BICR) per RECIST v1.1/RANO criteria. BICR-assessed confirmed objective response rate (cORR). Key secondary endpoints: duration of response (DoR); time to response (TtR); safety. As of 16 July 2023, out of 91 safety-evaluable patients, 64 (NTRK: n=44; ROS1: n=20) were efficacy evaluable. In the NTRK and ROS1 subgroups, respectively, median age was 4.0 years and 7.5 years; median survival follow-up was 24.2 months and 27.6 months. cORR was 72.7 % (NTRK, 95 % confidence interval [CI]: 57.2-85.0) and 65.0 % (ROS1, 95 % CI: 40.8-84.6). Median DoR was not reached (NTRK, 95 % CI: 25.4-not evaluable [NE]); ROS1, 95 % CI: 16.2-NE); median TtR was 1.9 months in both subgroups. The most frequently reported treatment-related adverse events included weight gain (35.2 %) and anaemia (31.9 %). Integrated data from three trials confirm entrectinib induces rapid and durable responses in children with NTRK or ROS1 fusion-positive tumours. The increased duration of safety monitoring does not demonstrate new or cumulative toxicity. Registered clinical trials: STARTRK-NG: NCT02650401; TAPISTRY: NCT04589845; STARTRK-2: NCT02568267.

PURPOSE: The tyrosine kinase receptor anaplastic lymphoma kinase (ALK) can be abnormally activated in neuroblastoma, and somatic ALK mutations occur in 6%-10% of patients. The differential clinical impact of these mutations has not been clearly elucidated. METHODS: Data on patients with neuroblastoma harboring ALK mutations were retrospectively analyzed. ALK sequencing was performed by whole-genome sequencing, hybrid-based capture of targeted exomes, or hotspot ALK mutation profiling. The differential impact of ALK mutation site on clinical characteristics, response to treatment, and survival was analyzed. In a subgroup of patients with locoregional neuroblastoma diagnosed after 2014, the impact of all ALK mutations was compared with wild-type ALK. RESULTS: Of 641 patients with neuroblastoma with ALK status analyzed on at least one tumor sample, 103 (16%) had tumors harboring ALK mutations. Mutations existed across all ages (birth to 67.8 years), stages (30% locoregional and 70% metastatic), and risk groups (20%, 11%, and 69% with low-, intermediate-, and high-risk disease, respectively). Mutation sites included F1174 (51%), R1275 (29%), R1245 (10%), and others (10%). Mutation site was not prognostic for progression-free survival or overall survival in the entire cohort, high-risk subgroup, or locoregional subgroup. Locoregional tumors with any ALK mutation were generally invasive: L2 by International Neuroblastoma Research Group staging in 30/31 patients with a 2-year progression-free survival (59%, 95% CI, 37.4 to 80.5) that was inferior to historical controls. This observation was corroborated in the post-2014 subgroup in which gross total resection was less likely for ALK-mutated tumors. CONCLUSION: Somatic ALK mutations are present across all stages and risk groups of neuroblastoma. No specific mutation carries differential prognostic significance. Locoregional neuroblastoma has an invasive phenotype when harboring somatic ALK mutations in this population.

MYCN -amplified stage 2/3 neuroblastoma: excellent survival in the era of anti-G D2 immunotherapy MYCN-Amplified stage 2/3 Neuroblastoma: Excellent Survival in the era of Anti-GD2 Immunotherapy

Purpose: Naxitamab is a humanized form of the murine anti-GD2 mAb 3F8. In an international trial, naxitamab + GM-CSF was effective against chemoresistant high-risk neuroblastoma (HR-NB), leading to approval by the FDA. We now report results with patients in first complete remission (CR). Patients and Methods: The primary objective of this phase II protocol 16-1643 (Clinicaltrials.gov NCT03033303) was to assess event-free survival of patients with HR-NB in first CR treated with naxitamab + GM-CSF plus isotretinoin. HR-NB was defined as MYCN-amplified disease (any age) or metastatic disease at age >18 months. Cycles of immunotherapy were administered monthly up to five cycles and comprised (i) subcutaneously administered priming doses of GM-CSF 250 μg/m2/day on days −4 to −0 (Wednesday–Sunday), followed by a step-up to 500 μg/m2/day on days +1 to +5 (Monday–Friday) and (ii) naxitamab infused intravenously (30–90”) on days +1, +3, and +5 (Monday–Wednesday–Friday, i.e., three doses/cycle). The dosage of naxitamab was 3 mg/kg/infusion (9 mg/kg/cycle, i.e., ∼270 mg/m2/cycle). The dosage of isotretinoin was 160 mg/m2/day started after cycle 2, ×14 days/course, and ×6 courses. Results: Fifty-nine patients with HR-NB (53 stage 4, 6 stage 3) were enrolled from February 2017 to July 2020. At 36 months, event-free/overall survival rates were 73%/93%, but 50 of 59 patients received after protocol treatment (vaccine and/or difluoromethylornithine). Six of 18 relapses were isolated in the central nervous system. Longer time from diagnosis to enrollment was a significantly adverse prognostic factor (P = 0.04). Twenty-one of 59 patients took no isotretinoin. Treatment was tolerable allowing outpatient administration. Conclusions: Naxitamab + GM-CSF is a good option to consolidate first CR of patients with HR-NB, including those who did not undergo autologous stem-cell transplantation. Efforts to prevent central nervous system relapse are warranted.