Neurological complications of neuroblastic tumors: experience of a single center

Five Years Follow-up of Opsoclonus-Myoclonus-Ataxia Syndrome-Associated Neurogenic Tumors in Children

AIM

 Opsoclonus-myoclonus-ataxia syndrome (OMAS) is a rare autoimmune disorder. Approximately half of the cases are associated with neuroblastoma in children. This study's aim is to review management of our cases with OMAS-associated neuroblastoma for treatment approach as well as long-term follow-up.

METHODS

 Age at onset of symptoms and tumor diagnosis, tumor location, histopathology, stage, chemotherapy, OMAS protocol, surgery, and follow-up period were evaluated retrospectively in six patients between 2007 and 2022.

RESULTS

 Mean age of onset of OMAS findings was 13.5 months and mean age at tumor diagnosis was 15.1 months. Tumor was located at thorax in three patients and surrenal in others. Four patients underwent primary surgery. Histopathological diagnosis was ganglioneuroblastoma in three, neuroblastoma in two, and undifferentiated neuroblastoma in one. One patient was considered as stage 1 and rest of them as stage 2. Chemotherapy was provided in five cases. The OMAS protocol was applied to five patients. Our protocol is intravenous immunoglobulin (IVIG) 1 g/kg/d for 2 consecutive days once a month and dexamethasone for 5 days (20 mg/m2/d for 1-2 days, 10 mg/m2/d for 3-4 days, and 5 mg/m2/d for the fifth day) once a month, alternatively by 2-week intervals. Patients were followed up for a mean of 8.1 years. Neuropsychiatric sequelae were detected in two patients.

CONCLUSION

 In tumor-related cases, alternating use of corticosteroid and IVIG for suppression of autoimmunity as the OMAS protocol, total excision of the tumor as soon as possible, and chemotherapeutics in selected patients seem to be related to resolution of acute problems, long-term sequelae, and severity.

Pediatric paravertebral tumors: analysis of 96 patients

PURPOSE

The most important complication of paravertebral tumors is cord compression (CC), which is an oncologic emergency. Early and appropriate intervention is important in terms of reducing morbidity and mortality. Here, we report our clinical experience with paravertebral tumors.

METHODS

The files of patients who were followed up for benign/malignant paravertebral tumors between 1988 and 2022 were evaluated retrospectively.

RESULTS

There were 96 patients with paravertebral tumors. The median age at diagnosis was 5 years (1 month-17 years). The male/female ratio was 1.13. The median time to diagnosis was 4 weeks (0-28 weeks). The most common presenting complaint was pain (62.5%). The diagnosis distribution was as follows: sympathetic nervous system (SNS) tumors (n: 38), soft tissue sarcomas (STS) (n: 23), Langerhans cell histiocytosis (LCH) (n: 12), central nervous system (CNS) tumors (n: 9), germ cell tumor (n: 6), lymphomas (n: 4), and benign tumors (n: 4). Sixty-five patients (67.7%) had CC, 40% of whom received chemotherapy as first-line treatment. Decompression surgery was performed in 58.5% of the patients. For patients with CC, 26 patients had advanced disease at admission. Serious neurologic sequelae were observed in seventeen (17.7%) patients.

CONCLUSION

Pain and neurological findings in childhood are warning signs for paravertebral tumors and CC. A detailed neurologic examination and radiodiagnostic imaging should be performed, and a definitive diagnosis should be made quickly. Anticancer treatment should be planned multidisciplinary. Decompression surgery should be discussed for patients with severe neurological deficits. Childhood cancers are chemosensitive; if possible, treatment should be initiated with chemotherapy to avoid neurological sequelae.

Demographic, Clinical, and Immunologic Features of 389 Children with Opsoclonus-Myoclonus Syndrome: A Cross-sectional Study

Pediatric-onset opsoclonus-myoclonus syndrome (OMS) is a devastating neuroinflammatory, often paraneoplastic, disorder. The objective was to characterize demographic, clinical, and immunologic aspects in the largest cohort reported to date. Cross-sectional data were collected on 389 children in an IRB-approved, observational study at the National Pediatric Myoclonus Center. Non-parametric statistical analysis was used. OMS manifested in major racial/ethnic groups, paralleling US population densities. Median onset age was 1.5 years (1.2–2 interquartile range), inclusive of infants (14%), toddlers (61%), and youngsters (25%). The higher female sex ratio of 1.2 was already evident in toddlers. Time to diagnosis was 1.2 months (0.7–3); to treatment, 1.4 months (0.4–4). Irritability/crying dominated prodromal symptomatology (60%); overt infections in <35%. Acute cerebellar ataxia was the most common misdiagnosis; staggering appeared earliest among 10 ranked neurological signs (P < 0.0001). Some untreated youngsters had no words (33%) or sentences (73%). Remote neuroblastic tumors were detected in 50%; resection was insufficient OMS treatment (58%). Age at tumor diagnosis related to tumor type (P = 0.004) and stage (P = 0.002). A novel observation was that paraneoplastic frequency varied with patient age—not a mere function of the frequency of neuroblastoma, which was lowest in the first 6 months of life, when that of neuroblastoma without OMS was highest. The cerebrospinal fluid (CSF) leukocyte count was minimally elevated in 14% (≤11/mm³) with normal differential, and commercially screened serum autoantibodies were negative, but CSF oligoclonal bands (OCB) and B cells frequency were positive (58 and 93%). Analysis of patients presenting on immunotherapy revealed a shift in physician treatment practice patterns from monotherapy toward multi-agent immunotherapy (P < 0.001); the number of agents/sequences varied. In sum, a major clinical challenge is to increase OMS recognition, prevent initial misdiagnosis, and shorten time to diagnosis/treatment. The index of suspicion for an underlying tumor must remain high despite symptoms of infection. The disparity in onset age of neuroblastoma frequency with that of neuroblastoma with OMS warrants further studies of potential host/tumor factors. OMS neuroinflammation is best diagnosed by CSF OCB and B cells, not by routine CSF or commercial antibody studies.

Treatment and outcome of neuroblastoma with intraspinal extension: A systematic review

We performed a systematic review to define the long-term health problems and optimal treatment strategy for patients with neuroblastoma with intraspinal extension. Of 685 identified studies, 28 were included in this review. The burden of long-term health problems is high; a median of 50% of patients suffered from neurological motor deficit, 34% from sphincter dysfunction, and 30% from spinal deformity. The currently available literature remains suboptimal as a guide for treatment of NBL with intraspinal extension. More well-designed, prospective studies are needed to determine the optimal treatment strategy.

Clinical responses to rituximab in a case of neuroblastoma with refractory opsoclonus myoclonus ataxia syndrome

Opsoclonus myoclonus ataxia syndrome (OMS) is a rare neurologic syndrome. In a high proportion of children, it is associated with neuroblastoma. The etiology of this condition is thought to be immune mediated. In children, immunotherapy with conventional treatments such as corticosteroids, intravenous immunoglobulin, adrenocorticotropic hormone, and even antiepileptic drugs has been tried. Recently rituximab has been used safely for refractory OMS in children with neuroblastoma. Our patient was a 3.5-year-old girl referred for ataxia and dancing eye movements starting since 1.5 years ago. She was diagnosed with neuroblastoma on imaging studies on admission. The OMS was refractory to surgical resection, chemotherapy, corticosteroids, and intravenous immunoglobulin. Patient received rituximab simultaneously with chemotherapy. The total severity score decreased by 61.1% after rituximab. Patient's ataxia markedly improved that she was able to walk independently after 6 months. Our case confirmed the clinical efficacy and safety of rituximab in a refractory case of OMS.

Short- and long-term outcome of patients with symptoms of spinal cord compression by neuroblastoma

AIM

Prospective trials on neuroblastoma-induced myelopathy are lacking. Therefore, we retrospectively analysed patients in four national neuroblastoma trials.

METHOD

Neuroblastoma patients diagnosed between August 1989 and December 2008 were included. Clinical and molecular data were available in the national trials database. Additional details on neurological findings, treatment, and outcome were collected using a questionnaire.

RESULTS

Among 2603 patients, 122 (61 males and 61 females) had symptoms of spinal cord compression (SCC), and 99 of these were included in the final long-term analysis. The survival of patients with symptoms of SCC was better than that of patients without symptoms. Patients first presented with lower extremity motor impairment (95%), impaired cutaneous sensibility (58%), neuropathic pain (56%), bladder dysfunction (44%), and/or constipation (34%). Symptoms improved after first-line neurosurgery in 36 out of 52 patients and after first line chemotherapy in 30 out of 47 patients (p=0.77). After a median observation time of 8 years 1 month (range 1mo-19y 6mo), 71 out of 99 patients still had residual impairments: motor impairment (43%), scoliosis (31%), impaired bladder function (26%), constipation (19%), impaired cutaneous sensibility (17%), growth delay (14%), and neuropathic pain (5%). The initial treatment had no clear impact on the frequency of late effects.

INTERPRETATION

This retrospective analysis showed no clear advantage of either first-line neurosurgery or chemotherapy and that most patients still exhibit residual symptoms and require specialized care.

Update on diagnosis, treatment, and prognosis in opsoclonus-myoclonus-ataxia syndrome

PURPOSE OF REVIEW

Opsoclonus-myoclonus-ataxia syndrome (OMS) is a severe autoimmune central nervous system disorder, which predominantly affects young children and causes lifelong neurological disability. Early recognition and treatment may yield better outcomes.

RECENT FINDINGS

Appreciation of the spectrum of clinical presentations of OMS, awareness of common misdiagnoses, and utilization of diagnostic criteria may facilitate the timely diagnosis of OMS. Approximately 50% of patients have an associated neuroblastoma, which may escape detection by traditional methods and require MRI or computed tomography of the torso for diagnosis. In nonparaneoplastic cases, many associated infections have been reported. Although there has been progress in autoantibody identification and cerebrospinal fluid B cell expansion is a common finding, there is no diagnostic biomarker for OMS currently. Approximately 80% of reported patients, typically treated with conventional therapies such as adrenocorticotropin hormone, corticosteroids, and/or intravenous immunoglobulin, develop long-term neurological morbidity. Newer treatment approaches using early, aggressive therapy with cyclophosphamide or rituximab are promising.

SUMMARY

The diagnosis of OMS requires a high level of suspicion and a systematic approach for diagnostic testing, particularly for neuroblastoma. Future collaborative studies are required to determine whether early, aggressive therapy will improve the typically poor long-term neurological outcome.