Glucosylceramide Synthase Inhibitors Induce Ceramide Accumulation and Sensitize H3K27 Mutant Diffuse Midline Glioma to Irradiation.

H3K27M mutant (mut) diffuse midline glioma (DMG) is a lethal cancer with no effective cure. The glycosphingolipids (GSL) metabolism is altered in these tumors and could be exploited to develop new therapies. We tested the effect of the glucosylceramide synthase inhibitors (GSI) miglustat and eliglustat on cell proliferation, alone or in combination with temozolomide or ionizing radiation. Miglustat was included in the therapy protocol of two pediatric patients. The effect of H3.3K27 trimethylation on GSL composition was analyzed in ependymoma. GSI reduced the expression of the ganglioside GD2 in a concentration and time-dependent manner and increased the expression of ceramide, ceramide 1-phosphate, sphingosine, and sphingomyelin but not of sphingosine 1-phosphate. Miglustat significantly increased the efficacy of irradiation. Treatment with miglustat according to dose recommendations for patients with Niemann-Pick disease was well tolerated with manageable toxicities. One patient showed a mixed response. In ependymoma, a high concentration of GD2 was found only in the presence of the loss of H3.3K27 trimethylation. In conclusion, treatment with miglustat and, in general, targeting GSL metabolism may offer a new therapeutic opportunity and can be administered in close proximity to radiation therapy. Alterations in H3K27 could be useful to identify patients with a deregulated GSL metabolism.

Mortality risk among 5-year survivors of childhood cancer in Germany-Results from the CVSS study (Cardiac and Vascular late Sequelae in long-term Survivors of childhood cancer study).

The growing population of long-term childhood cancer survivors is at increased risk for severe, therapy-related late effects and premature mortality. The cardiac and vascular late sequelae in long-term survivors of childhood cancer (CVSS) study is a cohort of patients from Germany diagnosed with a neoplasia prior to 15 years of age in the time period 1980 to 1990. Late mortality was evaluated in a total of 4505 individuals who survived 5 years or more after the initial diagnosis (5-year survivors). Survivors with a second primary tumor were excluded. Standardized mortality ratios (SMRs) were calculated. By December 2014, 400 patients had died. Available cause of death information from 188 individuals was used to estimate cause-specific mortality for all deceased persons. Compared to the population of (former) West Germany, we observed an excess overall mortality risk (SMR = 9.53, 95% confidence interval [CI] = 8.62-10.51). After correcting for missing cause of death information, an increased cancer mortality (SMR = 43.50, 95% CI = 25.79-73.50) in the 5-year survivors was detected. Cardiac death was ascertained in 14 individuals, resulting in an SMR of 10.85 (95% CI = 2.80-32.02) after correcting for missing values. In conclusion, childhood cancer survivors diagnosed in Germany in 1980 to 1990 have a higher mortality risk overall and an elevated risk of dying from cancer and cardiac causes in particular. The results are consistent with those of international cohort studies. However, the reported results are based on few cases and individuals with secondary cancers were excluded.

Ceritinib-Induced Regression of an Insulin-Like Growth Factor-Driven Neuroepithelial Brain Tumor.

The insulin-like growth factor (IGF) pathway plays an important role in several brain tumor entities. However, the lack of inhibitors crossing the blood-brain barrier remains a significant obstacle for clinical translation. Here, we targeted the IGF pathway using ceritinib, an off-target inhibitor of the IGF1 receptor (IGF1R) and insulin receptor (INSR), in a pediatric patient with an unclassified brain tumor and a notch receptor 1 (NOTCH1) germline mutation. Pathway analysis of the tumor revealed activation of the sonic hedgehog (SHH), the wingless and integrated-1 (WNT), the IGF, and the Notch pathway. The proliferation of the patient tumor cells (225ZL) was inhibited by arsenic trioxide (ATO), which is an inhibitor of the SHH pathway, by linsitinib, which is an inhibitor of IGF1R and INSR, and by ceritinib. 225ZL expressed INSR but not IGF1R at the protein level, and ceritinib blocked the phosphorylation of INSR. Our first personalized treatment included ATO, but because of side effects, we switched to ceritinib. After 46 days, we achieved a concentration of 1.70 µM of ceritinib in the plasma, and after 58 days, MRI confirmed that there was a response to the treatment. Ceritinib accumulated in the tumor at a concentration of 2.72 µM. Our data suggest ceritinib as a promising drug for the treatment of IGF-driven brain tumors.

Prospective analysis of long-term renal function in survivors of childhood Wilms tumor.

BACKGROUND: Considering the improved outcome, a better understanding of the late effects in Wilms tumor survivors (WT-S) is needed. This study was aimed at evaluating renal function and determining the prevalence of clinical and subclinical renal dysfunction in a cohort of WT-S using a multimodal diagnostic approach. METHODS: Thirty-seven WT-S were included in this prospective cross-sectional single center study. To evaluate renal function, glomerular filtration rate (GFR) and urinary protein excretion were assessed. Additionally, kidney sonomorphology and blood pressure were analyzed. RESULTS: All examined WT-S (mean age 28.7 years, mean follow-up 24.8 years) had been treated with a combination of surgery and chemotherapy; 59.5% had received adjuvant radiotherapy. Impaired glomerular renal function was detected in a considerable proportion of WT-S, with age-adjusted cystatin-based GFR estimation below age norm in 55.9%. A lower cystatin-based estimated GFR (eGFR) correlated with longer follow-up time and higher irradiation dose. In 5 patients (13.5%) albuminuria was identified. Analysis of sonomorphology detected compensatory contralateral renal hypertrophy in 83.3% of WT-S. Chronic kidney disease (CKD) ≥ stage II was present in 55.9% of WT-S. Blood pressure measurements revealed arterial hypertension in 15 (40.5%) WT-S (newly diagnosed n=10). In 24.3% both CKD ≥ stage II and arterial hypertension were determined. CONCLUSION: Even though WT-S are believed to carry a low risk for end-stage renal disease, in this study, a remarkable number of WT-S presented with previously unidentified subclinical signs of renal function impairment and secondary morbidity. Therefore, it is important to continue regular follow-up, especially after transition into adulthood.

Novel loss of function mutation in KRIT1/CCM1 is associated with distinctly progressive cerebral and spinal cavernous malformations after radiochemotherapy for intracranial malignant germ cell tumor.

PURPOSE: Cerebrospinal cavernous malformations (CCMs) are vascular lesions characterized by dilated and leaky capillary caverns. CCMs can cause seizures, focal neurological deficits or acute intracranial hemorrhage; however, most patients are asymptomatic. CCMs occur either sporadically or as a familial autosomal-dominant disorder. We present a clinical and molecular study of a patient with distinctive cerebral and spinal cavernous malformations following radiochemotherapy for a malignant brain tumor. METHODS: The patient had multiple magnet resonance imaging (MRI) examinations of his brain and spine following radiochemotherapy for a primary intracranial germ cell tumor (GCT), as part of his oncologic follow-up. The MRI sequences included susceptibility-weighted imaging (SWI). The coding exons and their flanking intronic regions of KRIT1/CCM1 gene were analyzed for mutations by polymerase chain reaction (PCR) and direct sequencing. RESULTS: MRI revealed numerous cerebral and spinal microhemorrhages and pronounced cavernous malformations that progressed with subsequent follow-up imaging. Genetic analysis demonstrated a novel heterozygous KRIT1/CCM1 two base pair deletion (c.1535_1536delTG) in exon 14. This deletion leads to a frameshift with a premature stop codon at nucleotide position 1553 and a highly likely loss of function of the KRIT1 protein. CONCLUSION: We describe a patient with a novel heterozygous germ line loss of function mutation in KRIT1, which is associated with rapid-onset and highly progressive CCMs after radiochemotherapy for a malignant brain tumor.

Next-generation sequencing reveals germline mutations in an infant with synchronous occurrence of nephro- and neuroblastoma.

Although neuro- and nephroblastoma are common solid tumors in children, the simultaneous occurrence is very rare and is often associated with syndromes. Here, we present a unique case of synchronous occurrence of neuro- and nephroblastoma in an infant with no signs of congenital anomalies or a syndrome. We performed genetic testing for possible candidate genes as underlying mutation using the next-generation sequencing (NGS) approach to target 94 genes and 284 single-nucleotide polymorphisms (SNPs) involved in cancer. We uncovered a novel heterozygous germline missense mutation p.F58L (c.172T→C) in the anaplastic lymphoma kinase (ALK) gene and one novel heterozygous rearrangement Q418Hfs(*)11 (c.1254_1264delins TTACTTAGTACAAGAACTG) in the Fanconi anemia gene FANCD2 leading to a truncated protein. Besides, several SNPs associated with the occurrence of neuroblastoma and/or nephroblastoma or multiple primary tumors were identified. The next-generation sequencing approach might in the future be useful not only in understanding tumor etiology but also in recognizing new genetic markers and targets for future personalized therapy.

Analysis of RBP expression and binding sites identifies PTBP1 as a regulator of CD19 expression in B-ALL.

Despite massive improvements in the treatment of B-ALL through CART-19 immunotherapy, a large number of patients suffer a relapse due to loss of the targeted epitope. Mutations in the CD19 locus and aberrant splicing events are known to account for the absence of surface antigen. However, early molecular determinants suggesting therapy resistance as well as the time point when first signs of epitope loss appear to be detectable are not enlightened so far. By deep sequencing of the CD19 locus, we identified a blast-specific 2-nucleotide deletion in intron 2 that exists in 35% of B-ALL samples at initial diagnosis. This deletion overlaps with the binding site of RNA binding proteins (RBPs) including PTBP1 and might thereby affect CD19 splicing. Moreover, we could identify a number of other RBPs that are predicted to bind to the CD19 locus being deregulated in leukemic blasts, including NONO. Their expression is highly heterogeneous across B-ALL molecular subtypes as shown by analyzing 706 B-ALL samples accessed via the St. Jude Cloud. Mechanistically, we show that downregulation of PTBP1, but not of NONO, in 697 cells reduces CD19 total protein by increasing intron 2 retention. Isoform analysis in patient samples revealed that blasts, at diagnosis, express increased amounts of CD19 intron 2 retention compared to normal B cells. Our data suggest that loss of RBP functionality by mutations altering their binding motifs or by deregulated expression might harbor the potential for the disease-associated accumulation of therapy-resistant CD19 isoforms.

Development and Phenotype of Heart Failure in Long-Term Survivors of Childhood Cancer: The CVSS Study.

Background The CVSS (Cardiac and Vascular Late Sequelae in Long-Term Survivors of Childhood Cancer) study aimed to investigate the prevalence of different stages of heart failure (HF) in childhood cancer survivors (CCSs) compared with the general population. Methods and Results A total of 1002 CCSs (age range, 23-48 years) diagnosed with neoplasia before an age of 15 years underwent a comprehensive cardiovascular screening. An age- and sex-matched sample from the population-based GHS (Gutenberg Health Study) served as a comparison group. Although prevalence of HF was significantly higher in CCSs, prevalence of different HF stages varied strongly by specific tumor history. Compared with the population, the prevalence ratio was 2.6 (95% CI, 2.4-2.8) for HF stage A and 4.6 (95% CI, 4.1-5.1) for the composite of HF stage B to D in an age- and sex-adjusted Poisson regression model. Multivariable linear regression, adjusting for tumor entities, age, sex, and cardiovascular risk factors, revealed a lower left ventricular ejection fraction in patients with history of bone tumors (ß, -4.30 [95% CI, -5.70 to -2.80]), soft tissue sarcoma (ß, -1.60 [95% CI, -2.90 to -0.30]), and renal tumors (ß, -1.60 [95% CI, -2.80 to -0.29]) compared with the population. The same model for the diastolic marker, ratio of the peak early diastolic filling velocity/lateral mitral annular early diastolic velocity, showed an association only with cardiovascular risk factors but not with tumor entities. Conclusions The prevalence of HF stage A to D was significantly higher among long-term CCSs compared with the population and varied strongly by tumor entity. Systolic dysfunction was primarily associated with tumor entities, whereas diastolic dysfunction was associated with a higher burden of cardiovascular risk factors in CCSs.

GD2 Expression in Medulloblastoma and Neuroblastoma for Personalized Immunotherapy: A Matter of Subtype.

Neuroblastoma (NBL) and medulloblastoma (MB) are aggressive pediatric cancers which can benefit from therapies targeting gangliosides. Therefore, we compared the ganglioside profile of 9 MB and 14 NBL samples by thin layer chromatography and mass spectrometry. NBL had the highest expression of GD2 (median 0.54 nmol GD2/mg protein), and also expressed complex gangliosides. GD2-low samples expressed GD1a and were more differentiated. MB mainly expressed GD2 (median 0.032 nmol GD2/mg protein) or GM3. Four sonic hedgehog-activated (SHH) as well as one group 4 and one group 3 MBs were GD2-positive. Two group 3 MB samples were GD2-negative but GM3-positive. N-glycolyl neuraminic acid-containing GM3 was neither detected in NBL nor MB by mass spectrometry. Furthermore, a GD2-phenotype predicting two-gene signature (ST8SIA1 and B4GALNT1) was applied to RNA-Seq datasets, including 86 MBs and validated by qRT-PCR. The signature values were decreased in group 3 and wingless-activated (WNT) compared to SHH and group 4 MBs. These results suggest that while NBL is GD2-positive, only some MB patients can benefit from a GD2-directed therapy. The expression of genes involved in the ganglioside synthesis may allow the identification of GD2-positive MBs. Finally, the ganglioside profile may reflect the differentiation status in NBL and could help to define MB subtypes.

Identification of an Immunogenic Medulloblastoma-Specific Fusion Involving EPC2 and GULP1.

Medulloblastoma is the most common malignant brain tumor in children. Immunotherapy is yet to demonstrate dramatic results in medulloblastoma, one reason being the low rate of mutations creating new antigens in this entity. In tumors with low mutational burden, gene fusions may represent a source of tumor-specific neoantigens. Here, we reviewed the landscape of fusions in medulloblastoma and analyzed their predicted immunogenicity. Furthermore, we described a new in-frame fusion protein identified by RNA-Seq. The fusion involved two genes on chromosome 2 coding for the enhancer of polycomb homolog 2 (EPC2) and GULP PTB domain containing engulfment adaptor 1 (GULP1) respectively. By qRT-PCR analysis, the fusion was detected in 3 out of 11 medulloblastoma samples, whereby 2 samples were from the same patients obtained at 2 different time points (initial diagnosis and relapse), but not in other pediatric brain tumor entities. Cloning of the full-length sequence indicated that the fusion protein contains the N-terminal enhancer of polycomb-like domain A (EPcA) of EPC2 and the coiled-coil domain of GULP1. In silico analyses predicted binding of the neoantigen-derived peptide to HLA-A*0201. A total of 50% of the fusions described in the literature were also predicted to produce an immunogenic peptide. The EPC2-GULP1 fusion peptide was able to induce a de novo T cell response characterized by interferon gamma release of CD8+ cytotoxic T cells in vitro. While the functional relevance of this fusion in medulloblastoma biology remains to be clarified, our data support an immunotherapeutic approach for pediatric medulloblastoma patients carrying the EPC2-GULP1 fusion and other immunogenic fusions.

Promotion of Arterial Stiffness by Childhood Cancer and Its Characteristics in Adult Long-Term Survivors.

Background Vascular alterations induced by antineoplastic treatment might be considered as a possible underlying mechanism of increased cardiovascular sequelae in childhood cancer survivors (CCSs). We aimed to evaluate arterial stiffness among long-term CCSs and to compare the data against a population-based sample. Methods and Results Arterial stiffness was assessed by digital photoplethysmography (stiffness index; m/s) among 1002 participants of the CVSS (Cardiac and Vascular Late Sequelae in Long-Term Survivors of Childhood Cancer) study, diagnosed with neoplasia (1980-1990) before an age of 15 years. A population-based sample from the GHS (Gutenberg Health Study) (n=5252) was investigated for comparison. All subjects underwent a comprehensive, standardized clinical examination in the same study center. CCSs had higher stiffness index (ß=0.66 m/s; 95% CI, 0.51-0.80 m/s) in multivariable linear regression analysis after adjustment for cardiovascular risk factors compared with the population sample of comparable age range. Stiffer vessels were found among CCSs also in absence of arterial hypertension (ß=0.66; 95% CI, 0.50-0.81) or history of chemotherapy/radiotherapy (ß=0.56; 95% CI, 0.16-0.96) in fully adjusted models. Moreover, stiffness index differed by tumor entity, with highest values in bone and renal tumors. Almost 5.2-fold higher prevalence of stiffness index values exceeding age-specific, population-based reference limits was observed among CCSs compared with GHS participants. Conclusions This is the first study demonstrating increased arterial stiffness among long-term CCSs. The data suggest that vascular compliance might differ in survivors of childhood cancer from the established development concept for arterial stiffness in the population; cancer growth and antineoplastic treatment might be relevant determinants of the pathobiological features. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02181049.

Exploiting Gangliosides for the Therapy of Ewing's Sarcoma and H3K27M-Mutant Diffuse Midline Glioma.

The ganglioside GD2 is an important target in childhood cancer. Nevertheless, the only therapy targeting GD2 that is approved to date is the monoclonal antibody dinutuximab, which is used in the therapy of neuroblastoma. The relevance of GD2 as a target in other tumor entities remains to be elucidated. Here, we analyzed the expression of GD2 in different pediatric tumor entities by flow cytometry and tested two approaches for targeting GD2. H3K27M-mutant diffuse midline glioma (H3K27M-mutant DMG) samples showed the highest expression of GD2 with all cells strongly positive for the antigen. Ewing's sarcoma (ES) samples also showed high expression, but displayed intra- and intertumor heterogeneity. Osteosarcoma had low to intermediate expression with a high percentage of GD2-negative cells. Dinutuximab beta in combination with irinotecan and temozolomide was used to treat a five-year-old girl with refractory ES. Disease control lasted over 12 months until a single partially GD2-negative intracranial metastasis was detected. In order to target GD2 in H3K27M-mutant DMG, we blocked ganglioside synthesis via eliglustat, since dinutuximab cannot cross the blood-brain barrier. Eliglustat is an inhibitor of glucosylceramide synthase, and it is used for treating children with Gaucher's disease. Eliglustat completely inhibited the proliferation of primary H3K27M-mutant DMG cells in vitro. In summary, our data provide evidence that dinutuximab might be effective in tumors with high GD2 expression. Moreover, disrupting the ganglioside metabolism in H3K27M-mutant DMG could open up a new therapeutic option for this highly fatal cancer.

Tumor Lipids of Pediatric Papillary Renal Cell Carcinoma Stimulate Unconventional T Cells.

Papillary renal cell carcinoma (PRCC) is a rare entity in children with no established therapy protocols for advanced diseases. Immunotherapy is emerging as an important therapeutic tool for childhood cancer. Tumor cells can be recognized and killed by conventional and unconventional T cells. Unconventional T cells are able to recognize lipid antigens presented via CD1 molecules independently from major histocompatibility complex, which offers new alternatives for cancer immunotherapies. The nature of those lipids is largely unknown and α-galactosylceramide is currently used as a synthetic model antigen. In this work, we analyzed infiltrating lymphocytes of two pediatric PRCCs using flow cytometry, immunohistochemistry and qRT-PCR. Moreover, we analyzed the CD1d expression within both tumors. Tumor lipids of PRCC samples and three normal kidney samples were fractionated and the recognition of tumor own lipid fractions by unconventional T cells was analyzed in an in vitro assay. We identified infiltrating lymphocytes including γδ T cells and iNKT cells, as well as CD1d expression in both samples. One lipid fraction, containing ceramides and monoacylglycerides amongst others, was able to induce the proliferation of iNKT cells isolated from peripheral blood mononuclear cells (PBMCs) of healthy donors and of one matched PRCC patient. Furthermore, CD1d tetramer stainings revealed that a subset of iNKT cells is able to bind lipids being present in fraction 2 via CD1d. We conclude that PRCCs are infiltrated by conventional and unconventional T cells and express CD1d. Moreover, certain lipids, present in pediatric PRCC, are able to stimulate unconventional T cells. Manipulating these lipids and T cells may open new strategies for therapy of pediatric PRCCs.

Benefits of Exercise Training for Children and Adolescents Undergoing Cancer Treatment: Results From the Randomized Controlled MUCKI Trial.

Objective: In cancer patients, the impairment in muscle function is a frequently observed phenomenon. However, comprehensive evaluation of the effect of exercise training on muscle function in childhood cancer patients (CCPs) is sparse and therefore investigated in the MUCKI trial. Study Design: In the randomized controlled MUCKI trial, CCPs during intensive cancer treatment and aged 4-18 years were recruited. Eligible patients were enrolled soon after diagnosis as long as they were physically and mentally able to participate in exercise testing and training. Patients of the exercise group (n = 16) participated in average 2.7 ± 1.2 times per week in a combined resistance and endurance training with moderate exercise intensity, for a time period of 8.0 ± 2.1 weeks, while patients of the control group (n = 17) received usual care. Leg strength was evaluated as the primary endpoint. Secondary endpoints were 6-min walk performance, arm strength, body composition, fatigue, and health-related quality of life. Results: Comparisons of pre- and post-intervention results were evaluated by baseline and stratification criteria adjusted analysis and showed positive effects for the exercise group regarding leg strength [F (1, 20) = 5.733; p = 0.027*; η p 2 = 0.223], walking performance [F (1, 25) = 4.270; p = 0.049*; η p 2 = 0.146], fatigue [F (1, 13) = 8.353; p = 0.013*; η p 2 = 0.391], self-esteem [F (1, 6) = 6.823; p = 0.040*; η p 2 = 0.532], and self-reported strength and endurance capacity [F (1, 6) = 6.273; p = 0.046*; η p 2 = 0.511]. No significant differences were found for the other parameters. Conclusion: Within one of the first randomized controlled trials, the present study provides evidence for a positive effect of combined training in CCPs during intensive cancer treatment. Further research is needed to confirm these results and to evaluate their clinical impact. Clinical Trial Registration Number: NCT02612025.

Safety and Activity of the Combination of Ceritinib and Dasatinib in Osteosarcoma.

Osteosarcoma (OS) is the second most common cause of cancer-related death in pediatric patients. The insulin-like growth factor (IGF) pathway plays a relevant role in the biology of OS but no IGF targeted therapies have been successful as monotherapy so far. Here, we tested the effect of three IGF specific inhibitors and tested ceritinib as an off-target inhibitor, alone or in combination with dasatinib, on the proliferation of seven primary OS cells. Picropodophyllin, particularly in combination with dasatinib and the combination ceritinib/dasatinib were effective in abrogating the proliferation. The ceritinib/dasatinib combination was applied to the primary cells of a 16-year-old girl with a long history of lung metastases, and was more effective than cabozantinib and olaparib. Therefore, the combination was used to treat the patient. The treatment was well tolerated, with toxicity limited to skin rush and diarrhea. A histopathological evaluation of the tumor after three months of therapy indicated regions of high necrosis and extensive infiltration of macrophages. The extension of the necrosis was proportional to the concentration of dasatinib and ceritinib in the area, as analysed by an ultra performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). After the cessation of the therapy, radiological analysis indicated a massive growth of the patient's liver metastases. In conclusion, these data indicate that the combination of ceritinib/dasatinib is safe and may be used to develop new therapy protocols.

Prevalence of mental distress among adult survivors of childhood cancer in Germany-Compared to the general population.

BACKGROUND: Increasing survival rates after childhood cancer have raised the issue of long-term mental health consequences in adulthood. This study determines mental health distress among long-term survivors of pediatric cancer and compares it to control groups. METHODS: Childhood cancer survivors (CCS; N = 951, aged 24-49 years) were compared to three age-matched control groups from the general population collected at three time points. The study compared the prevalence of clinically relevant symptoms of a wide range of common mental disorders (depression, somatic distress, suicidal ideation, generalized anxiety, panic, social anxiety, and sleep disturbances) using identical, validated questionnaires. CCS were identified by the German Childhood Cancer Registry. Controls were approached by a demographic consultation company (USUMA) which assured that the three samples were nationally representative. RESULTS: Childhood cancer survivors reported higher education than controls and were less often married. All forms of common mental distress were increased among survivors. Twenty-four percent of male (N = 526) and 41% of female survivors (N = 425) reported some form of clinically relevant mental health symptoms. Somatic distress as the leading complaint was highly frequent among CCS (OR: 10.98, CI 95%: 7.24-16.64). Complaints by generalized anxiety (OR: 5.04, CI 95%: 2.61-9.70), panic (OR: 3.28, CI 95%: 1.60-6.70), depression (OR: 3.36, CI 95%: 2.22-5.09), and suicidality (OR = 2.22; CI 95%: 1.38-3.57) were also strongly increased. Female sex, low education, low income, and unemployment were associated with increased distress. CONCLUSIONS: Findings indicate a need to integrate psycho-oncological screening and care into long-term aftercare. Somatic distress, as cause and indicator of psychological distress, should receive stronger attention, especially tiredness, low energy, and pain.

Radiation-induced vascular changes in the intracranial irradiation field in medulloblastoma survivors: An MRI study.

BACKGROUND AND PURPOSE: While survival times after treatment of medulloblastoma are increasing, little is known about radiochemotherapy (RCT)-induced cerebrovascular changes. High resolution vessel wall imaging (VWI) sequences are an emerging tool for the evaluation of cerebrovascular diseases. We performed VWI in medulloblastoma long-term survivors to screen for late sequelae of RCT. MATERIAL AND METHODS: Twenty-two pediatric medulloblastoma survivors (mean age 25.8 years (10-53 years); 16.3 years (mean) post primary RCT (range 1-45 years)) underwent 2D VWI-MRI. Vessel wall thickening, contrast enhancement and luminal narrowing were analyzed. The findings were correlated with the patients' radiation protocols. RESULTS: Vessel wall changes were observed the intracranial internal carotid artery (ICA) and the vertebrobasilar circulation (VBC) in 14 of 22 patients (63.6%). In multivariate analysis, time after RCT (OR = 1.38, p < 0.05) was strongest independent predictor for development of vessel wall alterations. The dose of radiation was not a relevant predictor. CONCLUSIONS: With longer follow-up time intracranial vessel wall changes are observed more frequently in medulloblastoma survivors. Thus VWI is a useful tool to monitor vessel wall alterations of cranially irradiated patients, creating the prerequisite for further treatment of late sequelae.

Relation between platelet coagulant and vascular function, sex-specific analysis in adult survivors of childhood cancer compared to a population-based sample.

Female sex is a risk factor for long-term adverse outcome in cancer survivors, however very little is known for the underlying pathophysiological mechanisms rendering the increased risk. This study investigated sex-specifically the relation between thrombin generation (TG) with and without presence of platelets and vascular function in 200 adult survivors of a childhood cancer compared to 335 population-based control individuals. TG lag time, peak height and endogenous thrombin potential (ETP) measured in presence and absence of platelets were correlated to reflection index (RI) and stiffness index (SI). A sex-specific correlation analysis showed a negative relation in female survivors for platelet-dependent peak height and/or ETP and RI only. An age adjusted linear regression model confirmed the negative association between RI and platelet-dependent ETP (beta estimate: -6.85, 95% confidence interval: -12.19,-1.51) in females. Adjustment for cardiovascular risk factors resulted in loss of the association, whereby arterial hypertension and obesity showed the largest effects on the observed association. No other relevant associations were found in male and female cancer survivors and all population-based controls. This study demonstrates a link between platelet coagulant and vascular function of resistance vessels, found in female cancer survivors, potentially mediated by the presence of arterial hypertension and obesity.

Susceptibility-weighted magnetic resonance imaging of cerebrovascular sequelae after radiotherapy for pediatric brain tumors.

BACKGROUND AND PURPOSE: Due to sensitive neuroimaging techniques, cerebrovascular complications such as cerebral microbleeds (CMB) and cerebral cavernous malformations (CCM) are increasingly recognized as considerable late effects after treatment for pediatric brain tumor. The aim of this study was to analyze CMB in a cohort of patients after cranial irradiation therapy for medulloblastoma or other pediatric brain tumors using susceptibility-weighted magnetic resonance imaging (SWI). MATERIALS AND METHODS: Forty former pediatric brain tumor patients were enrolled in this prospective cross-sectional study and examined by cranial MRI including SWI sequences. Cerebral microbleeds, clinical symptoms and disability were evaluated. RESULTS: Thirty-six (90%) of the examined individuals (mean follow-up age 22.2 y; mean follow-up time 13.5 y) were affected by CMB. Longer follow-up time and higher craniospinal irradiation doses correlated with higher total lesion count (p < 0.01). Thirteen patients (32.5%) presented with clinical symptoms. Individuals with CMB were more severely disabled than patients without CMB (p < 0.05). CONCLUSIONS: Cerebrovascular sequelae occur frequently after treatment for pediatric brain tumor. In this study, a remarkable part of pediatric brain tumor patients presents with CMB. As a sign of vascular damage, they can cause clinical symptoms and may correspond to neurocognitive decline. Further studies are needed to standardize MRI protocols and to improve quality of long-term follow-up.

CD19 Isoforms Enabling Resistance to CART-19 Immunotherapy Are Expressed in B-ALL Patients at Initial Diagnosis.

B-cell acute lymphoblastic leukemia (B-ALL) is the commonest childhood cancer and the prognosis of children with relapsed or therapy refractory disease remains a challenge. Treatment with chimeric antigen receptor-modified T cells targeting the CD19 antigen (CART-19 therapy) has been presented as a promising approach toward improving the outcome of relapsed or refractory disease. However, 10%-20% of the patients suffer another relapse. Epitope-loss under therapy pressure has been suggested as a mechanism of tumor cells to escape the recognition from CART-19 therapy. In this work, we analyzed the expression of CD19 isoforms in a cohort of 14 children with CD19 B-ALL and 6 nonleukemia donors. We showed that an alternatively spliced CD19 mRNA isoform lacking exon 2, and therefore the CART-19 epitope, but not isoforms lacking the transmembrane and cytosolic domains are expressed in leukemic blasts at diagnosis in children and in the bone marrow of nonleukemia donors. Furthermore, we clarified the sequence of a further isoform lacking the epitope recognized by CART-19 therapy and disclosed the presence of new isoforms. In comparison with the children, we showed that alternatively spliced CD19 mRNA isoforms affecting exon 2 are also expressed in 6 adult patients with CD19 B-ALL. On top of that, one of the adults expressed an isoform lacking the CD19 transmembrane and cytosolic domains. In conclusion, we proved that some of the CD19 isoforms contributing to CART-19 escape already preexist at diagnosis and could evolve as a dominant clone during CART-19 therapy suggesting the application of combined treatment approaches.