Mineralizing microangiopathy: radiological features of a "not uncommon" complication of chemoradiotherapy in pediatric cancer patients

Background

Mineralizing microangiopathy represents one of the delayed complications of radiotherapy and chemotherapy. We reviewed clinical and radiological data of pediatric cancer patients who presented with mineralizing microangiopathy. This is a retrospective analysis of the medical records of 37 cancer children treated with chemoradiotherapy presented with imaging criteria suspected of mineralizing microangiopathy admitted to our hospital during the period 2015–2020. The CT was reviewed for distribution of calcification and MRI for signal criteria.

This study aims to raise awareness among radiologists about radiological features of mineralizing microangiopathy during the sequential routine follow-up brain scans of pediatric cancer patients who received chemo, radio, or combined chemoradiotherapy and to identify changes as a long-term delayed complication of therapy and avoid misdiagnosis.

Results

Thirty-seven pediatric cancer patients (17 female and 20 males, aged 1.5–18 years) who had mineralizing microangiopathy were thoroughly investigated. Most of them (32 patients) had brain tumors and 5 patients had leukemia. Cranial radiotherapy and systemic chemotherapy were given to 33 patients, while nine patients received intrathecal chemotherapy. The interval needed to develop mineralizing microangiopathy ranged from 1 to 10 years after the end of treatment. CT detected calcification in the basal ganglia, being the most common location (32 cases), followed by cerebral gray–white matter interface in 26 patients, cerebellum (18), brain stem (13), thalamus (5), and caudate nucleus (4), while dural calcifications were found in only one patient. MRI was considered “positive” when T1 hyperintensity was noted in the anatomical location of CT detected calcification; it was positive in 29 cases.

Conclusion

Mineralizing microangiopathy is one of the delayed complications of chemoradiotherapy among pediatric cancer patients. The awareness of its radiological criteria is essential to avoid misdiagnosis. Early detection can alert pediatric oncologists to monitor neurotoxicity and help prevent long-term neurological sequels.

Imaging Findings in Children Presenting with CNS Nelarabine Toxicity

Nelarabine is a nucleoside analog critical for the treatment of patients with T-cell acute lymphoblastic leukemia/lymphoma. However, clinical peripheral and central neurologic adverse events associated with nelarabine administration have been reported. Neuroimaging of brain neurotoxicity has only been described in very few reports in pediatric patients so far. Six children with diagnosed T-cell acute lymphoblastic leukemia who clinically experienced possible, probable, or definite nelarabine-induced toxicity and underwent spine and/or brain MR imaging were reviewed. Neuroimaging findings showed a mixture of patterns including features of acute toxic leukoencephalopathy (seen in 6 cases), posterior reversible encephalopathy syndrome (2 cases), involvement of deep gray structures (1 case) and brainstem (2 cases), cranial and spinal neuropathy (2 cases each), and myelopathy (2 cases). Even though neuroimaging findings are nonspecific, the goal of this article was to alert the pediatric neuroradiologists, radiologists, and clinicians about the possibility of nelarabine-induced neurotoxicity and its broad neuroimaging spectrum.

Chemotherapy-related neurotoxicity in pediatric cancer patients: magnetic resonance imaging and clinical correlation

Background

Cancer is the second most common cause of death among children aged 1–14 years in the USA. Pediatric malignancies have elevated morbidity and mortality in the absence of proper treatment. Intensive treatment regimens have resulted in a significant increase in the number of survivors but also have been associated with the risk of developing neurotoxicity. The purpose of this study is to emphasize the role of advanced MRI techniques in the early detection of different chemotherapy neurotoxicities and make radiologists aware of them providing early management to prevent permanent damage.

Results

We evaluated 63 patients (43 males and 20 females), and their ages ranged from (2 to 17 years) with suspected chemotherapy-related neurotoxicity. MR examinations were performed with 1.5-T Philips systems. Clinical data were correlated with magnetic resonance imaging (MRI), and different treatment complications were diagnosed. All of our 63 patients were receiving chemotherapy treatment, and they developed different neurological symptoms. Patients diagnosed as posterior reversible encephalopathy syndrome were 41 with 8 patients had typical and 33 had atypical criteria, 16 patients diagnosed as cerebral venous sinus thrombosis with magnetic resonance venography (MRV) are the most important sequence that successfully diagnosed them, and finally, 6 patients diagnosed as methotrexate neurotoxicity with diffusion-weighted images (DWI) are the most important sequence for early diagnosis.

Conclusion

Chemotherapy is associated with certain neurotoxicities, conventional MRI can detect them, but by the use of advanced MRI techniques including MRV and DWI early detection of these neurotoxicities can occur. Therefore, the combination of conventional MRI together with advanced techniques improves the diagnostic efficacy of MRI in the early diagnosis of neurotoxicity.

Multifactorial Posterior Reversible Encephalopathy Syndrome in Children: Clinical, Laboratory, and Neuroimaging Findings

The aim of this study was to investigate the association of neuroimaging, clinical, and laboratory findings in children with different underlying diseases who developed posterior reversible encephalopathy syndrome (PRES). All consecutive pediatric patients referred to our institute between 2000 and 2017 were retrospectively evaluated for newly diagnosed PRES. Clinical data, medical history, and therapies administered at the time of PRES and laboratory findings were reviewed as the magnetic resonance imaging (MRI) obtained at PRES presentation and during follow-up. Statistics included Mann–Whitney U, Chi-square, and Fisher's exact tests. A total of 39 pediatric patients (25 males, median age = 8.8 years) with a confirmed diagnosis of PRES were included. The patients were divided into four groups based on the underlying disease: (1) patients with hemato-oncological diseases not transplanted (n = 15, 38.5%), (2) who underwent hematopoietic stem cell transplantation (HSCT; n = 12, 30.8%), (3) affected by renal (n = 8, 20.5%), and (4) by autoimmune diseases (n = 4, 10.2%). Hemato-oncological patients and those undergoing HSCT presented a higher incidence of involvement of deep gray matter structures and hemorrhagic lesions when compared with patients with renal and autoimmune disorders (p = 0.036 and p = 0.036, respectively). No differences emerged among different groups of patients regarding presenting PRES symptoms, arterial blood pressure, laboratory findings, and extent of MRI abnormalities and these parameters did not show association with outcome.

In conclusion, in pediatric patients with different diseases who develop PRES, involvement of deep gray matter structures and hemorrhagic lesions are more common in hemato-oncological patients and those undergoing HSCT. Clinical and radiologic outcome is favorable independently of clinical data and extent of MRI abnormalities.

Neuroradiologic findings and follow-up with magnetic resonance imaging of the genetic forms of haemophagocytic lymphohistiocytosis with CNS involvement

Haemophagocytic lymphohistiocytosis (HLH) is a rare hyperinflammatory syndrome caused by deficient down-regulation of the immune response. Presence of central nervous system (CNS) involvement at diagnosis is a poor prognostic sign, and should be carefully investigated. Herein, we describe the neuroradiological findings, clinical data, and treatment outcome in 12 patients with genetic HLH and CNS complications. Neuroimaging was important in identifying CNS involvement, monitoring treatment responses, and detecting treatment complications.