Long-term effects of cranial irradiation and intrathecal chemotherapy in treatment of childhood leukemia: a MEG study of power spectrum and correlated cognitive dysfunction

Neuropsychological task outcomes among survivors of childhood acute lymphoblastic leukemia in Malaysia

This study intended to explore the neuropsychological ramifications in childhood acute lymphoblastic leukemia (ALL) survivors in Malaysia and to examine treatment-related sequelae. A case-control study was conducted over a 2-year period. Seventy-one survivors of childhood ALL who had completed treatment for a minimum of 1 year and were in remission, and 71 healthy volunteers were enlisted. To assess alertness (processing speed) and essential executive functioning skills such as working memory capacity, inhibition, cognitive flexibility, and sustained attention, seven measures from the Amsterdam Neuropsychological Tasks (ANT) program were chosen. Main outcome measures were speed, stability and accuracy of responses. Mean age at diagnosis was 4.50 years (SD ± 2.40) while mean age at study entry was 12.18 years (SD ± 3.14). Survivors of childhood ALL underperformed on 6 out of 7 ANT tasks, indicating poorer sustained attention, working memory capacity, executive visuomotor control, and cognitive flexibility. Duration of treatment, age at diagnosis, gender, and cumulative doses of chemotherapy were not found to correlate with any of the neuropsychological outcome measures. Childhood ALL survivors in our center demonstrated significantly poorer neuropsychological status compared to healthy controls.

Genetic Factors and Long-term Treatment-Related Neurocognitive Deficits, Anxiety, and Depression in Childhood Leukemia Survivors: An Exome-Wide Association Study

BACKGROUND

An increased risk of neurocognitive deficits, anxiety, and depression has been reported in childhood cancer survivors.

METHODS

We analyzed associations of neurocognitive deficits, as well as anxiety and depression, with common and rare genetic variants derived from whole-exome sequencing data of acute lymphoblastic leukemia (ALL) survivors from the PETALE cohort. In addition, significant associations were assessed using stratified and multivariable analyses. Next, top-ranking common associations were analyzed in an independent SJLIFE replication cohort of ALL survivors.

RESULTS

Significant associations were identified in the entire discovery cohort (N = 229) between the AK8 gene and changes in neurocognitive function, whereas PTPRZ1, MUC16, TNRC6C-AS1 were associated with anxiety. Following stratification according to sex, the ZNF382 gene was linked to a neurocognitive deficit in males, whereas APOL2 and C6orf165 were associated with anxiety and EXO5 with depression. Following stratification according to prognostic risk groups, the modulatory effect of rare variants on depression was additionally found in the CYP2W1 and PCMTD1 genes. In the replication SJLIFE cohort (N = 688), the male-specific association in the ZNF382 gene was not significant; however, a P value<0.05 was observed when the entire SJLIFE cohort was analyzed. ZNF382 was significant in males in the combined cohorts as shown by meta-analyses as well as the depression-associated gene EXO5.

CONCLUSIONS

Further research is needed to confirm whether the current findings, along with other known risk factors, may be valuable in identifying patients at increased risk of these long-term complications.

IMPACT

Our results suggest that specific genes may be related to increased neuropsychological consequences.

Advances of neuroimaging in chemotherapy related cognitive impairment (CRCI) of patients with breast cancer

BACKGROUND

Chemotherapy related cognitive impairment (CRCI) has seriously affected the quality of life (QOL) of patients with breast cancer (BCs), thus the neurobiological mechanism of CRCI attracted widespread attention. Previous studies have found that chemotherapy causes CRCI through affecting brain structure, function, metabolism, and blood perfusion.

FINDINGS

A variety of neuroimaging techniques such as functional magnetic resonance imaging (fMRI), event-related potential (ERP), near-infrared spectroscopy (NIRS) have been widely applied to explore the neurobiological mechanism of CRCI.

CONCLUSION

This review summarized the progress of neuroimaging research in BCs with CRCI, which provides a theoretical basis for further exploration of CRCI mechanism, disease diagnosis and symptom intervention in the future. Multiple neuroimaging techniques for CRCI research.

Treatment of Radiation-Induced Brain Necrosis

Radiation-induced brain necrosis (RBN) is a serious complication of intracranial as well as skull base tumors after radiotherapy. In the past, due to the lack of effective treatment, radiation brain necrosis was considered to be progressive and irreversible. With better understanding in histopathology and neuroimaging, the occurrence and development of RBN have been gradually clarified, and new treatment methods are constantly emerging. In recent years, some scholars have tried to treat RBN with bevacizumab, nerve growth factor, and gangliosides and have achieved similar results. Some cases of brain necrosis can be repairable and reversible. We aimed to summarize the incidence, pathogenesis, and treatment of RBN.

Auditory attention late effects in pediatric acute lymphoblastic leukemia

This study sought to characterize auditory attention functioning among pediatric Acute Lymphoblastic Leukemia (ALL) survivors treated on a chemotherapy-only protocol, given previous literature suggesting late impact on sustained visual attention. We hypothesized similar deficits would be observed in auditory attention relative to previous literature indicating weakness with aspect of visual attention in this population. Survivors (n = 107, 53 females, M = 12.80 years) completed the Conners Continuous Auditory Test of Attention (CATA). Parents completed the Behavior Assessment System for Children, Second Edition and reported educational performance and services via structured questionnaire. Results indicated several CATA indices associated with sustained auditory attention were significantly worse than normative data, though group means were average. Reflecting individual variability in performance, 50% of the sample performed worse than one standard deviation from the mean on at least one CATA variable. Parent report of attention did not differ from normative means for the sample. Parent-report data indicated that 60% of the sample utilized academic support services, with a large proportion of survivors having utilized special education services. Poorer performance with sustained auditory attention was associated with poor academic outcomes. Greater methotrexate exposure and younger age at diagnosis were risk factors for inattentiveness. No gender differences were identified on direct assessment of auditory attention or parent report of attention, though male gender was associated with poorer educational performance. Findings suggest that auditory attention is an at-risk cognitive domain following treatment for pediatric ALL, and that an association exists between auditory attention and school performance in this population.

Cognitive Improvement After Kidney Transplantation Is Associated With Structural and Functional Changes on MRI

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Background.

Several studies have reported improved cognitive outcomes after kidney transplantation, but most studies either did not include controls or lacked extensive neuroimaging. In addition, there is uncertainty whether kidney donation is a safe procedure in terms of cognitive outcomes.

Methods.

We prospectively studied neurocognitive function in kidney transplant recipients. The primary outcome was change in neurocognitive function after 1 year compared with baseline, which was evaluated using the Amsterdam Neuropsychological Task battery and verbal fluency tests. Secondary outcomes included changes in depression and anxiety (measured by the Hospital Anxiety and Depression scale) and changes in fatigue (measured by the Checklist for Individual Strength). We included kidney donors to control for learning effects, socioeconomic status, and surgery. In addition, kidney transplant recipients were evaluated with MRI scans at baseline and at year 1. The MRI protocol included conventional MRI, automated volumetric measurement, diffusion tensor imaging, magnetic resonance spectroscopy, arterial spin labeling, and a resting state functional MRI.

Results.

Twenty-seven recipients and 24 donors were included. For both recipients and donors, neuropsychologic testing scores improved 1 year after transplantation (donation). Recipient improvement significantly exceeded donor improvement on tasks measuring attention and working memory. These improvements were associated with increases in white matter volume and N-acetylaspartate/creatine (a marker for neuronal integrity).

Conclusions.

Attention and working memory improve significantly 1 year after kidney transplantation. Learning effects do not account for these improvements because recipient improvement in these areas exceeds donor improvement and correlates with an improvement in white matter integrity after transplantation. Kidney donation appears to be a safe procedure in terms of cognitive outcomes.

Magnetic resonance imaging of changes in the brain of children cured of acute lymphoblastic leukemia

This study was aimed to systematize magnetic resonance imaging (MRI) presentation of toxic leukoencephalopathy, to find the correlation between method of central nervous system (CNS) leukemia prevention and changes on MRI, to find relationship between existence leukoencephalopathy on imaging and neurocognitive deficits in pediatric patients after anti-leukemic therapy. Brain MRI data of 48 children, who underwent a therapy course according to the ALL-MB intermediate risk protocol, was evaluated. In accordance with two arms of this protocol, they received either radiation therapy, or additional intrathecal administration of chemotherapeutic agents as a prevention of CNS leukemia. Also, neurocognitive tests were performed. According to the results of the performed investigation, 10 (50%) out of 20 children, who received cranial irradiation and 18 (66.6%) out of 27 patients, who received only intrathecal therapy demonstrated abnormal brain changes (leukoencephalopathy) according to MRI data. Leukoencephalopathy was mostly presented by diffuse zones and localized predominantly in the frontal and temporal lobes. There was no correlation between method of CNS prevention and the existence of leukoencephalopathy on MRI. The analysis of our data did not show significant differences in brain damage and severity of cognitive impairment depending on the type of prevention of CNS leukemia. Moreover, in this study no statistical correlation was found between leukoencephalopathy on MRI and neurocognitive impairment according to clinical tests data. Further long-term prospective studies and examinations should be performed to assess late neurotoxic effects.

Brain Connectivity and Cognitive Flexibility in Nonirradiated Adult Survivors of Childhood Leukemia

Background

This study aimed to assess functional and structural brain connectivity in adult childhood leukemia survivors and the link with cognitive functioning and previously identified risk factors such as intrathecal methotrexate dose and age at start of therapy.

Methods

Thirty-one nonirradiated adult childhood leukemia survivors and 35 controls underwent cognitive testing and multimodal magnetic resonance imaging (resting state functional MRI, T1-weighted, diffusion-weighted, and myelin water imaging [MWI]). Analyses included dual regression, voxel-based morphometry, advanced diffusion, and MWI modeling techniques besides stepwise discriminant function analysis to identify the most affected executive cognitive domain. Correlations with discrete intrathecal MTX doses and (semi)continuous variables were calculated using Spearman's rank and Pearson's correlation, respectively. All correlation tests were two-sided. Positive and negative T-contrasts in functional and structural MRI analysis were one-sided.

Results

Survivors demonstrated lower functional connectivity between the default mode network (DMN) and inferior temporal gyrus (ITG; P < .008). Additionally, we observed higher fractional anisotropy (FA; P = .04) and lower orientation dispersion index (ODI; P = .008) at the left centrum semiovale, which could-given that several fiber bundles cross this region-suggest selective reduced integrity of the respective white matter tracts. Set shifting reaction time, a measure of cognitive flexibility, was mostly impaired and correlated with lower FA (r = -0.53, P = .003) and higher ODI (r = 0.40, P = .04) in survivors but not with DMN-ITG connectivity. There were no statistically significant differences between survivors and controls in WM or GM volume, nor was there a statistically significant correlation between imaging measurements and age at start of therapy or intrathecal methotrexate dose.

Conclusions

Adult, nonirradiated childhood leukemia survivors show altered brain connectivity, which is linked with cognitive flexibility.

Influence of genetic factors on long-term treatment related neurocognitive complications, and on anxiety and depression in survivors of childhood acute lymphoblastic leukemia: The Petale study

BACKGROUND

A substantial number of survivors of childhood acute lymphoblastic leukemia suffer from treatment-related late adverse effects including neurocognitive impairment. While multiple studies have described neurocognitive outcomes in childhood acute lymphoblastic leukemia (ALL) survivors, relatively few have investigated their association with individual genetic constitution.

METHODS

To further address this issue, genetic variants located in 99 genes relevant to the effects of anticancer drugs and in 360 genes implicated in nervous system function and predicted to affect protein function, were pooled from whole exome sequencing data of childhood ALL survivors (PETALE cohort) and analyzed for an association with neurocognitive complications, as well as with anxiety and depression. Variants that sustained correction for multiple testing were genotyped in entire cohort (n = 236) and analyzed with same outcomes.

RESULTS

Common variants in MTR, PPARA, ABCC3, CALML5, CACNB2 and PCDHB10 genes were associated with deficits in neurocognitive tests performance, whereas a variant in SLCO1B1 and EPHA5 genes was associated with anxiety and depression. Majority of associations were modulated by intensity of treatment. Associated variants were further analyzed in an independent SJLIFE cohort of 545 ALL survivors. Two variants, rs1805087 in methionine synthase, MTR and rs58225473 in voltage-dependent calcium channel protein encoding gene, CACNB2 are of particular interest, since associations of borderline significance were found in replication cohort and remain significant in combined discovery and replication groups (OR = 1.5, 95% CI, 1-2.3; p = 0.04 and; OR = 3.7, 95% CI, 1.25-11; p = 0.01, respectively). Variant rs4149056 in SLCO1B1 gene also deserves further attention since previously shown to affect methotrexate clearance and short-term toxicity in ALL patients.

CONCLUSIONS

Current findings can help understanding of the influence of genetic component on long-term neurocognitive impairment. Further studies are needed to confirm whether identified variants may be useful in identifying survivors at increased risk of these complications.

Neurocognitive Sequelae in Adult Childhood Leukemia Survivors Related to Levels of Phosphorylated Tau

Central nervous system-directed prophylactic chemotherapy increases survival in childhood leukemia, but possible late neurocognitive sequelae remain a concern. We compared intellectual performance (WAIS IV), memory (AVLT), and executive functioning (ANT) between adult leukemia survivors (n = 31) and control individuals (n = 35). In survivors, cerebrospinal fluid (CSF) levels of phosphorylated Tau (p-Tau) during treatment and total intrathecal methotrexate dose correlated with adult intellectual performance (Pearson's and Spearman's coefficients, respectively). Long-term memory and attentional control, both maturing before survivors' mean age at diagnosis, were unaffected (P > .05 on all four subtests), in contrast to cognitive flexibility and information processing (P < .05 for eight of the subtests), which mature during adolescence. CSF p-Tau and methotrexate dose negatively correlated with intellectual performance (r = -0.414, P = .04 and r = -0.484, P = .007, respectively), but not with each other (r = 0.219, P = .29). These data identify CSF p-Tau as a predictor of late neurocognitive sequelae (in addition to methotrexate dose). Early identification of children at risk could inspire interventions to prevent or remediate chemotherapy-induced cognitive sequelae.

The Disparity of Impairment of Neurogenesis and Cognition After Acute or Fractionated Radiation Exposure in Adolescent BALB/c Mice

The effect of acute X-ray irradiation with 2 Gy or fractionated exposure with 0.2 Gy continuously for 10 days (0.2 Gy × 10 = 2 Gy) was evaluated in the postnatal day 21 (P21) BALB/c mouse model. Both acute and fractionated irradiation induced impairment of cell proliferation and neurogenesis in the subgranular zone of the dentate gyrus labeled by Ki67 and doublecortin, respectively. Parvalbumin immunopositive interneurons in the subgranular zone were also reduced significantly. However, the 2 patterns of irradiation did not affect animal weight gain when measured at ages of P90 and P180 or 69 and 159 days after irradiation. Behavioral tests indicated that neither acute nor fractionated irradiation with a total dose of 2 Gy induced deficits in the contextual fear or spatial memory and memory for novel object recognition. Animal motor activity was also not affected in the open-field test. The disparity of the impairment of neurogenesis and unaffected cognition suggests that the severity of impairment of neurogenesis induced by acute or fractionated irradiation with a total dose of 2 Gy at P21 may not be worse enough to induce the deficit of cognition.

Polyunsaturated Fatty Acids Are Associated With Behavior But Not With Cognition in Children With and Without ADHD: An Italian study

OBJECTIVE

This study aimed to investigate the relationship between polyunsaturated fatty acids (PUFAs) status, cognitive, and behavioral traits of ADHD in school-aged children.

METHOD

Seventy-three children with and without ADHD were assessed with cognitive tasks and behavioral rating scales including quality of life and global functioning at baseline of an intervention trial (clinicaltrials.gov NCT01796262). Correlation analyses were performed between the cognitive tasks/behavioral ratings and blood PUFA levels.

RESULTS

Children with ADHD had lower levels of DHA, omega-3 index, and total PUFA. PUFAs were positively associated with behavior but not consistently related to cognitive domains.

CONCLUSION

The present study confirms that children with ADHD display abnormal fatty acid profiles within an Italian setting. Furthermore, PUFAs were associated with behavior but not with cognition. Accordingly, for the first time, lower blood levels of PUFA were associated not only with symptoms of ADHD but also with a poorer quality of life.

Neurocognitive Outcomes and Interventions in Long-Term Survivors of Childhood Cancer

Recent research has demonstrated that survivors of childhood cancer are at risk for a myriad of late effects that affect physical and mental quality of life. We discuss the patterns and prevalence of neurocognitive problems commonly experienced by survivors of CNS tumors and acute lymphoblastic leukemia, the two most commonly researched cancer diagnoses. Research documenting the direct effects of tumor location and treatment type and intensity is presented, and patient characteristics that moderate outcomes (eg, age at diagnosis and sex) are discussed. Potential biologic mechanisms of neurotoxic treatment exposures, such as cranial irradiation and intrathecal and high-dose antimetabolite chemotherapy, are reviewed. Genetic, brain imaging, and neurochemical biomarkers of neurocognitive impairment are discussed. Long-term survivors of childhood cancer are also at risk for physical morbidity (eg, cardiac, pulmonary, endocrine) and problems with health behaviors (eg, sleep); research is reviewed that demonstrates these health problems contribute to neurocognitive impairment in survivors with or without exposure to neurotoxic therapies. We conclude this review with a discussion of literature supporting specific interventions that may be beneficial in the treatment of survivors who already experience neurocognitive impairment, as well as in the prevention of impairment manifestation.

Radioprotective effect of ursolic acid in radiation-induced impairment of neurogenesis, learning and memory in adolescent BALB/c mouse

The effect of acute irradiation with 5Gy or fractionated exposure with 0.5Gy continuously for 10days (a total dose of 5Gy) was evaluated in an immature BALB/c mouse model. Radioprotective effect of ursolic acid (at 25mg/kg/daily administered 1h after acute or each of fractionated irradiations, and continuously for 30days) was also investigated. We found that both acute and fractionated irradiation at a total dose of 5Gy did not induce any mortality within 30days after exposure to postnatal day 26 (P26) BALB/c mice, but reduced animal weigh gain in the first few weeks. At 90days after irradiation, the weight of animals with acute irradiation was still significantly lower than the control group; no significant difference though was observed for those fractionatedly exposed mice compared to the control group. Behavioral tests indicated that acute irradiation at 5Gy induced deficits in learning and memory in the contextual fear conditioning test. The memory for novel object recognition was also impaired. Similar changes were not observed in mice with fractionated irradiation. Immunohistochemical study demonstrated clearly that acute and fractionated irradiations induced impairment of neurogenesis in the subgranular zone (SGZ) of the dentate gyrus although fractionated exposure induced much lesser loss of newly generated neurons. Ursolic acid administered at 25mg/kg/daily for 30days after irradiation greatly improved acute irradiation-induced deficits in contextual learning and memory and in novel object recognition memory although it exacerbated radiation-induced reduction of neurogenesis in SGZ.

Postnatal irradiation-induced hippocampal neuropathology, cognitive impairment and aging

Irradiation of the brain in early human life may set abnormal developmental events into motion that last a lifetime, leading to a poor quality of life for affected individuals. While the effect of irradiation at different early developmental stages on the late human life has not been investigated systematically, animal experimental studies suggest that acute postnatal irradiation with ⩾0.1Gy may significantly reduce neurogenesis in the dentate gyrus and endotheliogenesis in cerebral vessels and induce cognitive impairment and aging. Fractionated irradiation also reduces neurogenesis. Furthermore, irradiation induces hippocampal neuronal loss in CA1 and CA3 areas, neuroinflammation and reduces gliogenesis. The hippocampal neurovascular niche and the total number of microvessels are also changed after radiation exposures. Each or combination of these pathological changes may cause cognitive impairment and aging. Interestingly, acute irradiation of aged brain with a certain amount of radiation has also been reported to induce brain hormesis or neurogenesis. At molecular levels, inflammatory cytokines, chemokines, neural growth factors, neurotransmitters, their receptors and signal transduction systems, reactive oxygen species are involved in radiation-induced adverse effect on brain development and functions. Further study at different omics levels after low dose/dose rate irradiation may not only unravel the mechanisms of radiation-induced adverse brain effect or hormesis, but also provide clues for detection or diagnosis of radiation exposure and for therapeutic approaches to effectively prevent radiation-induced cognitive impairment and aging. Investigation focusing on radiation-induced changes of critical brain development events may reveal many previously unknown adverse effects.

Executive Dysfunction 25 Years after Treatment with Cranial Radiotherapy for Pediatric Lymphoid Malignancies

The first cohorts to survive childhood lymphoid malignancies treated with cranial irradiation are now aging into adulthood, and concerns are growing about the development of radiotherapy-induced cognitive deficits in the aging brain. These deficits are hypothesized to increase over time. Their impact on daily functioning of older survivors, and the accompanying need for interventions, should be anticipated. By describing a detailed profile of executive function deficits and their associations with age, specific targets for neuropsychological intervention can be identified. Fifty survivors of childhood lymphoid malignancies and 58 related controls were assessed with the Amsterdam Neuropsychological Tasks program. The survivors were on average 31.1 (4.9) years old, treated with 22.5 (6.8) Gy cranial irradiation, and examined on average 25.5 (3.1) years after diagnosis. The survivors showed significantly decreased response speed, irrespective of the task at hand. Furthermore, we found deficits in working memory capacity, inhibition, cognitive flexibility, executive visuomotor control, attentional fluctuations, and sustained attention. Older age was associated with poorer performance on executive visuomotor control and inhibition. On executive visuomotor control, 50% of female survivors performed more than 1.5 SD below average, versus 15.4% of male survivors. The combination of visuospatial working memory problems and decreasing executive visuomotor control could result in difficulty with learning new motor skills at older ages, like walking with a cane. Deterioration of executive control and inhibition may result in decreased behavioral and emotional regulation in aging survivors. Especially the deficiency in executive visuomotor control in female survivors should be considered for (prophylactic) intervention.

Neurocognitive outcomes in long-term survivors of childhood acute lymphoblastic leukemia treated on contemporary treatment protocols: A systematic review

The intensified administration of chemotherapeutic drugs has gradually replaced cranial radiation therapy (CRT) for the treatment of childhood acute lymphoblastic leukemia (ALL). While CRT is often implicated in neurocognitive impairment in ALL survivors, there is a paucity of the literature that evaluates the persistence of neurocognitive deficits in long-term survivors of pediatric ALL who were treated with contemporary chemotherapy-only protocols. Results from this systematic review concurred to the probable cognitive-sparing effect of chemotherapy-based protocols over CRT in long-term survivors. However, coupled with multiple intrinsic and extrinsic factors, survivors who received chemotherapy treatment still suffered from apparent cognitive impairment, particularly in the attention and executive function domains. Notably, there is evidence to suggest that the late neurotoxic effect of methotrexate on survivors' neurocognitive performance may be dose-related. This review also recommends future pharmacokinetic, neuroimaging and genetic studies to illuminate the multifactorial nature of this subject matter and discusses the potential value of neurochemical, physiological, inflammatory and genetic markers for the prediction of susceptibility to neurocognitive impairment in long-term survivors of childhood ALL.

Potential toxicities of prophylactic cranial irradiation

Prophylactic cranial irradiation (PCI) with total doses of 20-30 Gy reduces the incidence of brain metastasis (BM) and increases survival of patients with limited and extensive-disease small-cell lung cancer (SCLC) that showed any response to chemotherapy. PCI is currently not applied in non-small-cell lung cancer (NSCLC) since it has not proven to significantly improve OS rates in stage IIIA/B, although novel data suggest that subgroups that could benefit may exist. Here we briefly review potential toxicities of PCI which have to be considered before prescribing PCI. They are mostly difficult to delineate from pre-existing risk factors which include preceding chemotherapy, patient age, paraneoplasia, as well as smoking or atherosclerosis. On the long run, this will force radiation oncologists to evaluate each patient separately and to estimate the individual risk. Where PCI is then considered to be of benefit, novel concepts, such as intensity-modulated radiotherapy and/or neuroprotective drugs with potential to lower the rates of side effects will eventually be superior to conventional therapy. This in turn will lead to a re-evaluation whether benefits might then outweigh the (lowered) risks.

What are the long-term effects of treatment on survivors of childhood leukaemia? A review of the literature

Purpose

Key advances in cancer treatment have led to an increasing number of long-term cancer survivors. Knowledge of the long-term effects of cancer treatment on leukaemia survivors is to some degree limited. This article investigates the effects of the treatment of childhood leukaemia on the quality of life (QOL), the physical and the psychological wellbeing and general development of survivors. This article reviews current literature to examine existing gaps in knowledge and identify a potential focus of future research and clinical practice.

Materials and methods

Online systematic searching, along with historical searching took place in order to retrieve relevant primary research papers for the review. Strict inclusion and exclusion criteria were applied to the literature, to create a manageable amount of research papers.

Results

The extent of intellectual impairment among radiotherapy patients was significantly greater than those treated with chemotherapy only. Body composition, including endocrine function, is readily affected by cancer treatment. Early identification and interventions can greatly improve the QOL of survivors.

Conclusion

Further research into the effect of treatment modality on the extent of chronic effects, along with investigations into the needs of the whole family unit, is required. Future practice must take into account long-term implications while ensuring effective holistic care.

Perforin- and granulysin-mediated cytotoxicity and interleukin 15 play roles in neurocognitive impairment in patients with acute lymphoblastic leukaemia

Acute lymphoblastic leukaemia (ALL) is an aggressive disease. The course of disease is regulated by pro-inflammatory agents, and malignant cell infiltration of tissues plays a deleterious role in disease progression, greatly impacting quality of life, especially in the cognitive domains. Our hypothesis is that significant serum concentrations of interleukin 15 (IL-15) are responsible for higher expression of adhesion molecules on endothelial cells of blood-brain barrier (BBB) which allow leukaemia cells and/or normal lymphocytes the infiltration into the brain. In brain tissue these cells could be stimulated to release perforin and granulysin causing induction of apoptosis in brain cells that are involved in complex neural signalling mediated by neurotransmitters, and consequent fine cognitive impairment. Such changes could be detected early, even before notable clinical psycho-neurological or radiological changes in patients with ALL. To evaluate this hypothesis we propose measuring cognitive function using Complex Reactiometer Drenovac (CRD) scores in patients with ALL. The expression of different adhesion molecules on BBB as well as presence and distribution of different lymphocytes in brain tissue will be analyzed. We will then correlate CRD scores with levels of IL-15 and the percentages of T cells, natural killer T cells, and natural killer cells expressing perforin and/or granulysin proteins. CRD is a scientifically recognised and highly sensitive psychometric laboratory test based on the complex chronometric mathematical measuring of speed of reaction to various stimuli. It provides an objective assessment of cognitive functions from the most complex mental activities to the simplest reaction reflexes. Early recognition of cognitive dysfunction might be important when selecting the most appropriate chemotherapy and/or radiotherapy regimens, and could allow for the implementation of preventive measures against further deterioration in cognitive function and quality of life in patients with ALL.

Assessment of neuropsychological late effects in survivors of childhood leukemia

The neurologic dysfunctions caused by treatment may affect health and quality of life in survivors of childhood leukemia. The objective of this study was to identify the neuropsychological late effects of leukemia treatment to provide an assessment about the degree and incidence of these late effects. Neurological and ophtalmological examination, cranial magnetic resonance imaging (MRI), auditory and neurocognitive tests, and questionnaires of quality of life were performed to 44 acute leukemia survivors at least 5 years after diagnosis. Median time since completion of chemotherapy was 7.5 years (2-18) and median age at the time of the study was 16.4 years (8-31). At least one or more late effects detected by physical examination (PE), neurological tests, or neurocognitive tests encountered in 80% of the patients, and 64% of the patients specified at least one complaint in the quality of life questionnaire. MRI revealed pathological findings in 18% and electroencephalogram (EEG) abnormalities were present in 9% of the patients. Evaluation of total intelligence scores revealed that 30% of patients' IQ scores were <80 and 70% of the patients' scores demonstrated neurocognitive dysfunctions. The patients >6 years at the time of diagnosis were found to have more psychological problems and higher rates of smoking and alcohol consumption. The most frequent complaint was headache and the most common problem in school was denoted as difficulty in concentration. Our study demonstrated that most of the survivors of childhood leukemia are at risk of developing neuropsycological late effects.

Accelerated aging, decreased white matter integrity, and associated neuropsychological dysfunction 25 years after pediatric lymphoid malignancies

PURPOSE

CNS-directed chemotherapy (CT) and cranial radiotherapy (CRT) for childhood acute lymphoblastic leukemia or lymphoma have various neurotoxic properties. This study aimed to assess their impact on the maturing brain 20 to 30 years after diagnosis, providing a much stronger perspective on long-term quality of life than previous studies.

PATIENTS AND METHODS

Ninety-three patients treated between 1978 and 1990 at various intensities, with and without CRT, and 49 healthy controls were assessed with magnetic resonance diffusion tensor imaging (DTI) and neuropsychological tests. Differences in fractional anisotropy (FA)-a DTI measure describing white matter (WM) microstructure-were analyzed by using whole brain voxel-based analysis.

RESULTS

CRT-treated survivors demonstrated significantly decreased FA compared with controls in frontal, parietal, and temporal WM tracts. Trends for lower FA were seen in the CT-treated survivors. Decreases in FA correlated well with neuropsychological dysfunction. In contrast to the CT group and controls, the CRT group showed a steep decline of FA with age at assessment. Younger age at cranial irradiation and higher dosage were associated with worse outcome of WM integrity.

CONCLUSION

CRT-treated survivors show decreased WM integrity reflected by significantly decreased FA and associated neuropsychological dysfunction 25 years after treatment, although effects of CT alone seem mild. Accelerated aging of the brain and increased risk of early onset dementia are suspected after CRT, but not after CT.