Risk factors in long-term sequelae of central nervous system prophylaxis in successfully treated children with acute lymphocytic leukemia

Pseudoprogression after high-dose busulfan-thiotepa with autologous stem cell transplantation and radiation therapy in children with brain tumors: Impact on survival

Children with a brain tumor treated with high-dose busulfan-thiotepa with autologous stem cell transplantation (ASCT) and radiation therapy (RT) often experience radiographic changes during follow-up. The purpose of the study was to identify the incidence, time course, risk factors, and clinical outcome of this complication. From May 1988 through May 2007, 110 patients (median age, 3.6 years; range, 1 month to 15.3 years) with a brain tumor had received 1 course of high-dose busulfan-thiotepa with stem cell rescue, followed or preceded by RT as part of their treatment. All MRI follow-up examinations were systematically reviewed. Twenty-three patients (21%) developed neuroradiological abnormalities at a median time of 9.2 months (range, 5.6-17.3 months) after ASCT. All contrast-enhancing lesions appeared in patients who had received RT after ASCT and were localized inside the 50-55Gy isodoses. They disappeared in 14 of 23 patients after a median time of 8 months (range, 3-17 months), leaving microcalcifications in some cases. The presence of MRI abnormalities was an independent prognostic factor for overall survival in the multivariate analysis (hazard ratio, 0.12; 95% confidence interval [CI], 0.04-0.33), with a 5-year overall survival rate of 84% among patients with MRI abnormalities (95% CI, 62-94), compared with 27% (95% CI, 19-37) among those without lesions. MRI-detectable pseudoprogression is a common early finding in children treated with high-dose busulfan-thiotepa followed by radiation therapy and is correlated with a better outcome.

Magnetic resonance imaging in childhood leukemia survivors treated with cranial radiotherapy: a cross sectional, single center study

BACKGROUND

Children treated with cranial radiotherapy (CRT) for leukemia are at risk of developing central nervous system injuries. Magnetic resonance imaging (MRI) represents the examination method of choice for evaluating radiation-induced brain complications. The purpose of this report is to describe the spectrum of MRI abnormalities detected in a group of survivors of leukemia treated with cranial irradiation.

PROCEDURES

In this cross-sectional, single center study, 56 patients (median age at follow-up 19 years) receiving CRT as cranial prophylaxis (CP) included in the leukemia protocol (total dose 1,800-2,400 cGy) and/or in the total body irradiation regimen (990-1,200 cGy) before hematopoietic stem cell transplant, were evaluated by MRI after a median interval of 11 years (range 2-27) following CRT.

RESULTS

Fifty-nine MRI abnormalities (32 cavernomas, nine focal areas of gliosis, seven dystrophic mineralizations, five cerebral atrophies, four pituitary atrophies, one diffuse radiation leukoencephalopathy, and one meningioma) were found in 43 patients. The longest interval between CRT and MRI and oldest age at follow-up represented the two risk factors that were statistically associated with MRI lesions (P = 0.032 and 0.033, respectively). Cerebral cavernomas (CC) were the most frequent MRI abnormalities (57%). All patients with CC were asymptomatic at diagnosis and during follow-up, except one who had aspecific neurological manifestations and micro hemorrhages.

CONCLUSIONS

These results confirm that total doses and modalities of fractionation dose of CRT were not significantly associated with MRI abnormalities. Moreover, in our experience none of the patients developed neurological symptoms related to MRI abnormalities, and furthermore, the CC remained substantially stable during follow-up.

White Matter Lesions Detected by Magnetic Resonance Imaging After Radiotherapy and High-Dose Chemotherapy in Children With Medulloblastoma or Primitive Neuroectodermal Tumor

Purpose

White matter lesions (WMLs) have been described as a delayed effect of cranial irradiation in children with brain tumors, or a transient subacute effect characterized by an intralesional or perilesional reaction. We report the occurrence of subacute WMLs detected by magnetic resonance imaging (MRI) in children treated for medulloblastoma or primitive neuroectodermal tumor (PNET) and document the associated clinical, radiologic, and neurocognitive findings.

Patients and Methods

Among 134 patients with medulloblastoma or supratentorial PNET treated prospectively with risk-adjusted craniospinal irradiation and conformal boost to the tumor bed, followed by four high-dose chemotherapy (HDC) cycles with stem-cell rescue, 22 developed WMLs on T1-weighted imaging with and without contrast and/or T2-weighted imaging on MRI. Patients had ≥ 12 months of follow-up. Neurocognitive assessments included intelligence quotient (IQ) tests and tests of academic achievement.

Results

Twenty-two patients developed WMLs at a median of 7.8 months after starting therapy (range, 1.9 to 13.0 months). Lesions were predominantly in the pons (n = 8) and cerebellum (n = 6). Sixteen patients (73%) had WML resolution at a median of 6.2 months (range, 1.68 to 23.5 months) after onset; two patients developed necrosis and atrophy. Three developed persistent neurologic deficits. Cumulative incidence of WMLs at 1 year was 15% ± 3%. Patients with WMLs had a significant decline in estimated IQ (−2.5 per year; P = .03) and math (−4.5 per year; P = .003) scores.

Conclusion

WMLs in medulloblastoma or PNET patients treated with conformal radiotherapy and HDC are typically transient and asymptomatic, and may mimic early tumor recurrence. A minority of patients with WMLs develop permanent neurologic deficits and imaging changes. Overall, the presence of WMLs is associated with greater neurocognitive decline.

Cognitive functions of adolescent childhood cancer survivors assessed by event-related potentials

BACKGROUND

Neurophysiological methods were applied to examine subtle central nervous system (CNS) adverse effects for adolescent childhood cancer survivors. We analyzed auditory event-related potentials (ERPs)-P300 and MMN/P3a complex-to find out whether there was impaired attention orientation in asymptomatic cancer survivors, and whether these ERP methods could be used as more objective tools in detecting those survivors who might need academic testing. Previous clinical studies of P300 have focused on leukemia survivors. MMN for cancer survivors has not been reported.

PROCEDURE

The subjects were survivors of childhood leukemia (n=11) and solid tumors (n=8), as well as healthy controls (n=10). The mean age was 15.5 years for survivors and 15.9 years for controls. Pure sine-wave tones (500 and 553 Hz, 100 ms) were used as stimuli in an oddball paradigm. The ERPs to frequency change were measured. MMN recordings were performed in a passive non-attended situation where the subject was watching a voiceless video cartoon. P300 was produced thereafter, but in an active attend situation, by the same auditory oddball paradigm as MMN.

RESULTS

A significant difference was detected between the groups for the latency of P300 at electrodes Cz (P = 0.03) and C4 (P = 0.05). The cancer survivors had prolonged P300 latencies as an indication of prolonged short-term memory processing. The area and latency parameters of MMN did not differ significantly between the study groups, but in cancer survivors, the area and the mean amplitude of the subsequent P3a wave were diminished. The results indicate that the discrimination process was not as easy for the survivors as for the controls. However, it seems that in cancer survivors the basic mechanism starting attention shift to novel stimuli is not impaired.

CONCLUSIONS

These results indicate that it is important to carefully evaluate the proper methods for the teaching of children who are survivors of malignancies. The auditory information may not always lead to the best possible learning results.

CNS late effects after ALL therapy in childhood. Part I: Neuroradiological findings in long-term survivors of childhood ALL--an evaluation of the interferences between morphology and neuropsychological performance. The German Late Effects Working Group

The effect of cranial irradiation on possible therapy-induced morphological central nervous system (CNS) side effects of children cured from acute lymphoblastic leukemia (ALL) is controversially discussed. In a retrospective multicenter study, 118 former ALL patients in first continuous remission were investigated using cranial computerised tomography (CCT) or magnetic resonance imaging (MRI) scans to evaluate CNS related impairments. Corresponding to the different kinds of CNS prophylaxis, the patient sample was divided: group A (n = 39) receiving intrathecal methotrexate (ITMTX) and systemical medium-high-dose methotrexate (SMHDMTX), group B (n = 41) cranial irradiated (in mean 16.8 Gy) and administering ITMTX and SMHDMTX, group C (n = 38) irradiated (in mean 17.1 Gy) and getting ITMTX. Pathologic scans showed atrophy, leukoencephalopathy, calcifications or grey matter changes. These findings were compared with the neuropsychological test results. Abnormal MRI or CCI scans were found in 61/118 patients (51.7%). Fifteen belonged to group A (38.5%), 23 to B (56.1%) and 23 to C (60.5%). Patients with definite CNS changes show reduced neuropsychological test results. The prevalence of brain alterations seems to appear twice increased after lengthening the posttherapeutic interval in irradiated patients as in nonirradiated patients. Irradiated patients as an age younger than 2 years at diagnosis may show a lower prevalence for developing CNS alterations. CNS alterations are not sex-related. Children treated with cranial irradiation in combination with SMHDMTX and/or ITMTX were at greater risk of developing morphological brain alterations than patients with chemotherapy alone. These alterations are partly correlated with reduced neuropsychological performances and seem to stay with a longer posttherapeutic interval.

Long-term sequelae of therapy for childhood acute lymphoblastic leukaemia

Childhood ALL has provided the model for basic therapeutic principles in the past and now provides the model for late effects studies. Common threads which run throughout the literature in this area of clinical research are the importance of young age with increased vulnerability to long-term treatment induced sequelae and the relatively large contribution of radiation as compared with chemotherapy in the pathogenesis of adverse sequelae. Previous retrospective studies of long-term childhood ALL survivors focused on neuropsychologic changes and anatomic changes in the CNS after cranial irradiation. More recent retrospective studies have made the following new observations: (i) the high frequency of significant short adult stature in those less than 6 years of age at diagnosis who received 24 Gy cranial irradiation; (ii) actuarial risk of 2.5% of developing a second malignancy with approximately one-half of secondary malignancies occurring in the CNS in children 5 years of age or less who received cranial irradiation; (iii) the association of secondary ANLL with epipodophyllo-toxin use, and (iv) delayed cardiac toxicity despite anthracycline dosage reduction. Current therapy regimens, especially in high-risk patients, are both more successful and more intensive than those used in the past. While it will be another decade before many of the long-term sequelae begin to emerge, one can anticipate, based on current experience, some of the problems that will occur.

Cranial computed tomography in children with acute lymphoblastic leukemia after prophylactic treatment with cranial radiation therapy and intrathecal methotrexate

BACKGROUND AND METHODS

Thirty-one children with acute lymphoblastic leukemia (ALL) who had received cranial radiation therapy (CrRT) and five concomitant doses of intrathecal methotrexate (IT MTX) for central nervous system prophylaxis (CNSP) and who had an event-free survival exceeding 5 years had cranial computed tomography (Cr CT) examination. The fractional dose for 21 of them was 1.5 Gy. The interval between the completion of CNSP and the time of Cr CT ranged from 5 to 8.5 years, with a median of 5 years 2 months.

RESULTS

Unlike the previous reports in the literature that 9-77% of children with ALL who had received Cr RT 18 Gy and IT MTX as CNSP had CT scan abnormalities, in this study no patient had CT scan abnormalities.

CONCLUSIONS

Our results might be attributable to the fractional dose of Cr RT being adequate, the IT chemotherapy being suitable, and the systemic chemotherapy not being intensive.

Cranial computed tomographic findings in children with newly diagnosed acute lymphoblastic leukemia: a prospective follow-up study during treatment

Cranial computed tomography (CT) was performed on 40 consecutive children with newly diagnosed acute lymphoblastic leukemia (ALL) on admission before any chemotherapy, 5 months after CNS therapy (n = 39) and after 2 to 3 years of therapy (n = 31). Changes related to leukemia were found in only 10% of the patients at the time of diagnosis (4/40). These initial changes, two intracranial hemorrhages, one dural thickening and one contrast enhancement, all disappeared during therapy. The findings which persisted unchanged in the next two CT scans were thought to be normal variations or caused by earlier disorders. CNS therapy consisted of intrathecally and intravenously administered methotrexate in 20 standard risk (SR) patients and cranial irradiation in addition to chemotherapy in 19 intermediate risk (IR) or high risk (HR) patients. Four SR patients developed changes during therapy. Three had enlarged cerebrospinal fluid (CSF) spaces and one developed a focal low density area suggesting disturbances in brain blood circulation and also experienced disturbances in level of consciousness. Of the 19 IR or HR patients, eight developed changes related to the therapy, including four with white matter hypodensity areas, of whom three also had enlarged CSF spaces, and four others who developed enlarged CSF spaces. The medians of the widths of the cortical sulci (P less than .001), insular cisterns (P less than .01), third ventricles (P less than .01), and frontal horns (P less than .05), and also of Evans' ratios (P less than .05) increased significantly after CNS therapy as compared with the findings at diagnosis in the patients who had received cranial irradiation. Most of these changes persisted during the follow-up. We conclude that the clinical value of CT scanning during therapy for ALL is restricted to patients with neurological symptoms or those who have undergone CNS irradiation.

Influence of age, sex, and concurrent intrathecal methotrexate therapy on intellectual function after cranial irradiation during childhood: a report from the Children's Cancer Study Group

Standard IQ tests were performed in 70 children and adolescents 3.5-10 years (median 5 yrs) after 24 Gy cranial irradiation, with or without concurrent intrathecal methotrexate, for central nervous system prophylaxis of acute lymphoblastic leukemia. Lower IQ scores correlated with younger age, female gender, and concomitant intrathecal methotrexate therapy. Multivariate analysis identified age as the most important determinant of the three factors. The lowest IQ scores were observed in girls who were less than 5 years old at the time of irradiation and who received concurrent intrathecal methotrexate. The observed adverse contribution of simultaneous intrathecal methotrexate therapy on IQ outcome may have significant implications for school performance, peer relationships, and occupational expectations.

Minimal neuropsychological sequelae following prophylactic treatment of the central nervous system in adult leukaemia and lymphoma

The potential long-term toxicity of central nervous system prophylaxis (CNS-P) in adult acute lymphoblastic leukaemia (ALL, n = 17) and non-Hodgkin's lymphoma (NHL, n = 7) was investigated in a multidisciplinary study. At least 4 years had elapsed from CNS-P (mean 11.5 years) for all patients. Neurological history and physical examination were unremarkable; minor signs were commoner in older patients (P less than 0.02). Psychometry yielded normal results, but individual verbal IQ generally exceeded performance IQ, with a trend to more marked differences in younger adults (P = 0.06). EEG was scored and differed significantly from that of controls, with a tendency to more marked (but still minor) abnormalities in younger patients (P = 0.06). Brainstem auditory evoked potentials demonstrated significant but generally minor abnormality in 24% of patients. CT brain scan revealed widening of cerebral hemisphere sulci to greater than 3 mm in 38% of patients; cerebral atrophy was commoner in the older group (P less than 0.02) and those with neurological signs (P less than 0.02). MRI brain scans were normal in all patients tested. Thus, following standard CNS-P for ALL at this hospital, there is a 5% primary CNS relapse rate, and only minimal, mainly subclinical, long-term neuropsychological toxicity.

Curability of third ventricular region tumours. A multidisciplinary approach to evaluate the places of operative, radiation and chemotherapy

Between 1976 and 1988, 17 patients suffering from tumours located in the third ventricular region were entered into a retrospective study. There were 11 males and 6 females aged from 2 to 30. These tumours were located in the pineal area (n = 12), in the floor of the third ventricle (n = 3), in the roof of the third ventricle (n = 1) and multiple midline tumours (n = 1). A ventriculoperitoneal shunt was performed in 13 patients. In 8 patients the tumour was operated upon directly. 2 patients did not undergo surgery. A histological examination was performed in 13 cases with identification of 9 germinomas, 2 pinealoblastomas and one astrocytoma. In one case the plasma and cerebro-spinal-fluid level of tumour markers (human béta chorionic gonadotrophin & alpha feto protein) were elevated. All patients received 45 to 60 grays by cobalt megavoltage irradiation on the tumoural volume, 8 of them receiving additional whole brain and spinal irradiation ranging from 30 to 36 grays. One patient had chemotherapy in addition to radiotherapy. The 5 years survival rate was 74% and the mean follow-up period was 5 years. Five deaths occurred: 1 during irradiation, 3 following a relapse and 1 unexplained death later on. There were no neurological sequelae related to irradiation but 7 patients (37%) had pituitary insufficiency. The irradiation dose level required to obtain local control, the methods of spinal prophylactic treatment and the role of chemotherapy are discussed.

Correlation between cranial computed tomographic scans at diagnosis in children with acute lymphoblastic leukaemia and central nervous system relapse

145 children with acute lymphoblastic leukaemia (ALL) were evaluated over a period of 3 years in a multicentre study in which serial cranial computed tomographic (CT) scans of the brain were done. All patients were symptom-free. CT scans were graded as normal, borderline (slight or moderate cerebral atrophy), or pathological (severe cerebral atrophy). 62% (90/145) of children had CT scan abnormalities at diagnosis. After a median follow-up of 24 months (range 6-36) 12 of 108 evaluable patients had central nervous system (CNS) relapses (6 isolated relapses and 6 combined with relapse at another site). All patients with CNS relapse had an abnormal CT scan at diagnosis (8 pathological and 4 borderline). No relapses were observed among the 42 patients with a normal cranial CT scan at diagnosis. A significantly higher proportion of severe cerebral atrophy, both following CNS prophylaxis and after the discontinuation of treatment, was found among patients with a borderline CT scan at diagnosis than among patients with a normal CT scan at diagnosis. Thus an abnormal cranial CT scan at diagnosis in children with ALL seems to have prognostic significance.

Late effects of antileukemic treatment

Increasing numbers of childhood ALL survivors have increased the need to assess the physical and psychosocial functioning of this group in a careful manner. This article reviews data on the frequency and types of second malignancies, structural and functional changes in the central nervous system, endocrine effects on growth and reproduction, and psychosocial aspects of development. Most long-term survivors of ALL do not have serious or life-threatening medical problems; however, medical and psychosocial problems may not be insignificant and may require coordinated management over prolonged periods.

Central nervous system leukemia

With one exception, the risk and severity of neurotoxicity is directly proportional to the number of therapeutic modalities used. Three are worse than two, and two are worse than one. Combinations of therapeutic modalities which include CNS RT appear to be the most neurotoxic. The least neurotoxic combination of two modalities appears to be the IT MTX with high-dose intravenous MTX. Thus far, high-dose MTX appear to be the safest single modality, in terms of acute, subacute, and delayed neurotoxicity. The improved outcome in intellectual and academic performance in the NCI-191/CCG-134P conjoint trial of the CCSG and the Pediatric Branch described above (see section of Presymptomatic CNS Therapy) appears to confirm this observation. Whether triple IT chemotherapy will have the same result remains to be established. If CNS RT must be combined with MTX therapy, the least neurotoxic approach appears to be to administer these modalities in sequence, IT MTX, or high-dose intravenous MTX followed by CNS RT. MTX given during or after CNS RT appears from the clinical data to be more likely to produce severe neurologic sequelae. An ultimate goal would be to avoid both ionizing RT and IT chemotherapy. To this end, the NCI/CCSG study has demonstrated that this may be possible, except for those patients who are at the highest risk for CNS relapse despite conventional CNS prophylaxis. Meanwhile, for presymptomatic therapy, either cranial RT (18 Gy total dose at 120-180 cGy per day) in conjunction with IT MTX, or frequent IT chemotherapy with MTX, cytarabine, and hydrocortisone combined and administered throughout induction, consolidation, and maintenance is eminently justified in the majority of children with ALL. On a worldwide basis, chemoradiotherapy with cranial RT and IT MTX remains the established method of preventing overt CNS leukemia. The benefits of this intervention, in terms of prevention of symptomatic CNS leukemia, prolongation of complete remission, and increased cure rates, are clearly worth the risks.

Leptomeningeal cancer in leukemia and solid tumors

Although some patients with overt leptomeningeal cancer can now be cured, the proportion of patients who survive is very small, and the cost of cure, in terms of neuropsychological and educational morbidity, is substantial. Yet the incidence of central nervous system infiltration of systemic cancer is generally increasing, in most instances because control of systemic cancer has sufficiently prolonged survival to permit leptomeningeal metastases to develop and become symptomatic or detectable. The best chance for prolongation of life and possible cure is early detection and aggressive therapy in those forms of cancer that are amenable to therapy. We review the incidence of the various forms of leptomeningeal metastases, current concepts of pathogenesis and pathophysiology, clinical and laboratory features of leptomeningeal cancer, the available therapies, and the associated toxicities. The various methods that have been used to prevent and treat leptomeningeal cancer are described with an emphasis on childhood acute lymphoblastic leukemia (ALL) because it plays a predominant role in our understanding of meningeal neoplasms in general.