Epidural compression in infants less than 6 months of life with neuroblastoma: experience of Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology

Abstract

Neuroblastoma (NB) can manifest through neurological symptoms caused by tumor extension into the spinal canal and the resulting epidural compression (EC). Clinical symptoms and management in patients with epidural compression depend on its level and duration, the severity of spinal cord compression, the patient's age and other factors. One of the biggest challenges is the diagnosis and treatment of EC in infants in the first months of life. Our retrospective analysis included 13 patients with NB complicated by spinal cord EC who had been diagnosed at the age of 0–6 months and treated at the D. Rogachev NMRCPHOI over the period from 01.01.2012 to 01.12.2018 (82 months). The study was approved by the Independent Ethics Committee and the Scientific Council of the D. Rogachev NMRCPHOI of the Ministry of Healthcare of the Russian Federation. The diagnosis of NB was based on the international diagnostic criteria. The tumors were staged in accordance with the INSS classification. The patients were stratified into risk groups and treated according to the modified NB-2004 protocol of the German Oncology Group. All the patients underwent diagnostic testing for neurogenic tumors as well as contrast-enhanced magnetic resonance imaging of the spinal cord with the assessment of the level of tumor invasion and the degree of spinal cord compression. The children were evaluated by a neurologist at admission and at follow-up visits. The median age at diagnosis of NB was 3.9 (0.5–6) months. At disease onset, 53.8% of patients had neurological symptoms, with motor deficiencies being the most common ones. In this group of patients, the median time from first neurological symptoms to diagnosis of NB was 1.56 months. Neurological symptoms at disease onset were not present or diagnosed at local healthcare facilities in 46.2% of infants. Extra-organic retroperitoneal primary tumors were found in 61.6% of patients; 30.7% of primary tumors were located in the posterior mediastinum, and 7.7% of primary tumors – in the lesser pelvis. No patients had MYCN-amplified tumors; in 1 case the MYCN gene status was evaluated as Gain; neither 1p nor 11q deletions were detected. The distribution of patients by INSS stages was as follows: stage 2 – 15.3%, stage 3 – 46.1%, stage 4 – 23.3% and stage 4S – 15.3%. The majority of patients (77.7%) were stratified into an observation group, the remaining patients (23.3%) were allocated to a medium risk group in accordance with the NB-2004 protocol. The level of tumor invasion into the spinal cord canal varied. Tumor invasion at the level of the cervicothoracic spine was observed in 15.4% of patients, at the level of the thoracic spine – in 15.4%, at the level of the thoracolumbar spine – in 46.2%, at the level of the lumbar spine – in 15.4%, and at the level of the sacral spine – in 7.7%. Neurosurgical intervention (laminotomy) was performed in 4 cases (30.7%). In one patient, laminotomy was the only treatment option (chemotherapy was not given). In two patients, neurosurgery was performed because of the deterioration of neurological symptoms caused by the start of the first polychemotherapy (PCHT) cycle. Chemotherapy was carried out in 92.3% patients. The patients from the observation group received 1–3 PCHT cycles (the median number of cycles was 2). Only one patient from the observation group did not receive PCHT. This patient underwent 2 surgeries. Currently, 10/13 (77%) patients are alive, 3/13 (33%) patients are dead (2/3 patients died of therapy-related infectious complications, and 1/3 – of acute heart failure in the early postoperative period). The median follow-up was 37.3 months. According to the assessment of late effects, neurological disorders were found in all the analyzed patients (n = 9), and orthopedic disorders were found in 66.6% (6/9) patients. The results of our analysis illustrate both the difficulty of diagnosis and management of EC in patients with NB and the need¬ for uniform testing and treatment standards with established follow-up and rehabilitation strategies for this group of patients.