Hypothalamic-pituitary function of children with acute lymphocytic leukemia after three forms of central nervous system prophylaxis. A retrospective study

Central Endocrine Complications Among Childhood Cancer Survivors Treated With Radiation Therapy: A PENTEC Comprehensive Review

PURPOSE

Children who receive cranial radiation therapy (RT) as a component of treatment for malignancy are often at risk of long-term central endocrine toxicity secondary to radiation to the hypothalamic-pituitary axis (HPA). A comprehensive analysis was performed of central endocrine late effects in survivors of childhood cancer treated with RT as part of the Pediatric Normal Tissue Effects in the Clinic (PENTEC) consortium.

METHODS AND MATERIALS

A systematic review of the risk of RT-related central endocrine effects was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A total of 4629 publications were identified, of which 16 met criteria for inclusion in dose modeling analysis, with a total of 570 patients in 19 cohorts. Eighteen cohorts reported outcomes for growth hormone deficiency (GHD), 7 reported outcomes for central hypothyroidism (HT), and 6 reported outcomes for adrenocorticotropic hormone (ACTH) deficiency.

RESULTS

Normal tissue complication probability modeling for GHD (18 cohorts, 545 patients) yielded D50 = 24.9 Gy (95% CI, 20.9-28.0) and γ50 = 0.5 (95% CI, 0.27-0.78). The normal tissue complication probability model fit for whole brain irradiation in children with a median age of >5 years indicated a 20% risk of GHD for patients who receive a mean dose of 21 Gy in 2-Gy fractions to the HPA. For HT, among 7 cohorts (250 patients), D50 = 39 Gy (95% CI, 34.1-53.2) and γ50 = 0.81 (95% CI, 0.46-1.35), with a 20% risk of HT in children who receive a mean dose of 22 Gy in 2-Gy fractions to the HPA. For ACTH deficiency (6 cohorts, 230 patients), D50 = 61 Gy (95% CI, 44.7-119.4) and γ50 = 0.76 (95% CI, 0.5-1.19); there is a 20% risk of ACTH deficiency in children who receive a mean dose of 34 Gy in 2-Gy fractions to the HPA.

CONCLUSIONS

RT dose to the HPA increases the risk of central endocrine toxicity, including GHD, HT, and ACTH deficiency. In some clinical situations, these toxicities may be difficult to avoid, and counseling of patients and families with respect to anticipated outcomes is important.

DNLC: differential network local consistency analysis

BACKGROUND

The biological network is highly dynamic. Functional relations between genes can be activated or deactivated depending on the biological conditions. On the genome-scale network, subnetworks that gain or lose local expression consistency may shed light on the regulatory mechanisms related to the changing biological conditions, such as disease status or tissue developmental stages.

RESULTS

In this study, we develop a new method to select genes and modules on the existing biological network, in which local expression consistency changes significantly between clinical conditions. The method is called DNLC: Differential Network Local Consistency. In simulations, our algorithm detected artificially created local consistency changes effectively. We applied the method on two publicly available datasets, and the method detected novel genes and network modules that were biologically plausible.

CONCLUSIONS

The new method is effective in finding modules in which the gene expression consistency change between clinical conditions. It is a useful tool that complements traditional differential expression analyses to make discoveries from gene expression data. The R package is available at https://cran.r-project.org/web/packages/DNLC.

Hypothalamic-Pituitary Disorders in Childhood Cancer Survivors: Prevalence, Risk Factors and Long-Term Health Outcomes

CONTEXT

Data on hypothalamic-pituitary (HP) disorders in systematically evaluated childhood cancer survivors are limited.

OBJECTIVE

To describe prevalence, risk factors, and associated adverse health outcomes of deficiencies in GH deficiency (GHD), TSH deficiency (TSHD), LH/FSH deficiency (LH/FSHD), and ACTH deficiency (ACTHD), and central precocious puberty (CPP).

DESIGN

Retrospective with cross-sectional health outcomes analysis.

SETTING

Established cohort; tertiary care center.

PATIENTS

Participants (N = 3141; median age, 31.7 years) were followed for a median 24.1 years.

MAIN OUTCOME MEASURE

Multivariable logistic regression was used to calculate ORs and 95% CIs for associations among HP disorders, tumor- and treatment-related risk factors, and health outcomes.

RESULTS

The estimated prevalence was 40.2% for GHD, 11.1% for TSHD, 10.6% for LH/FSHD, 3.2% for ACTHD, and 0.9% for CPP among participants treated with HP radiotherapy (n = 1089), and 6.2% for GHD, and <1% for other HP disorders without HP radiotherapy. Clinical factors independently associated with HP disorders included HP radiotherapy (at any dose for GHD, TSHD, LH/FSHD, >30 Gy for ACTHD), alkylating agents (GHD, LH/FSHD), intrathecal chemotherapy (GHD), hydrocephalus with shunt placement (GHD, LH/FSHD), seizures (TSHD, ACTHD), and stroke (GHD, TSHD, LH/FSHD, ACTHD). Adverse health outcomes independently associated with HP disorders included short stature (GHD, TSHD), severe bone mineral density deficit (GHD, LH/FSHD), obesity (LH/FSHD), frailty (GHD), impaired physical health-related quality of life (TSHD), sexual dysfunction (LH/FSHD), impaired memory, and processing speed (GHD, TSHD).

CONCLUSION

HP radiotherapy, central nervous system injury, and, to a lesser extent, chemotherapy are associated with HP disorders, which are associated with adverse health outcomes.

Isolated late testicular relapse of B-cell acute lymphoblastic leukemia treated with intensive systemic chemotherapy and response-based testicular radiation: A Children's Oncology Group study

BACKGROUND

The incidence of isolated testicular relapse (ITR) of acute lymphoblastic leukemia (ALL) has decreased with contemporary treatment strategies, but outcomes are suboptimal with a 58% 5-year overall survival (OS). This study aimed to improve outcome in patients with ITR of B-cell ALL (B-ALL) occurring after 18 months of first clinical remission using intensive systemic chemotherapy and to decrease long-term sequelae by limiting use of testicular radiation.

PROCEDURE

Forty patients in first ITR of B-ALL were enrolled. Induction (dexamethasone, vincristine, daunorubicin, and intrathecal triple therapy) was preceded by one dose of high-dose methotrexate (MTX, 5 g/m² ). Following induction, 25 of 26 patients who had persistent testicular enlargement underwent testicular biopsy. Eleven had biopsy-proven disease and received bilateral testicular radiation (24 Gy), whereas twenty-nine did not.

RESULTS

Overall 5-year event-free survival (EFS)/OS was 65.0 ± 8.8%/73.1 ± 8.3%, with 5-year EFS 62.1 ± 11.0% vs. 72.7 ± 14.4% for patients who did not receive radiation therapy (XRT) (n = 29) compared with those who did (n = 11), respectively (P = 0.64). There were six second bone marrow relapses and six second ITRs. The proportion of second relapses was similar in the patients that received testicular radiation and those who did not. However, the 5-year OS was similar for patients who did not receive XRT (72.6 ± 10.2%) compared with those who did (72.7 ± 14.4%) (P = 0.85).

CONCLUSIONS

A 5-year OS rate of 73.1 ± 8.3% was obtained in children with first ITR of B-ALL occurring after 18 months of CR1 (length of first clinical remission) using intensive chemotherapy and limiting testicular radiation.

Late thyroid complications in survivors of childhood acute leukemia. An L.E.A. study

Thyroid complications are known side effects of irradiation. However, the risk of such complications in childhood acute leukemia survivors who received either central nervous system irradiation or hematopoietic stem cell transplantation is less described. We prospectively evaluated the incidence and risk factors for thyroid dysfunction and tumors in survivors of childhood acute myeloid or lymphoid leukemia. A total of 588 patients were evaluated for thyroid function, and 502 individuals were assessed for thyroid tumors (median follow-up duration: 12.6 and 12.5 years, respectively). The cumulative incidence of hypothyroidism was 17.3% (95% CI: 14.1-21.1) and 24.6% (95% CI: 20.4-29.6) at 10 and 20 years from leukemia diagnosis, respectively. Patients who received total body irradiation (with or without prior central nervous system irradiation) were at higher risk of hypothyroidism (adjusted HR: 2.87; P=0.04 and 2.79, P=0.01, respectively) as compared with transplanted patients who never received any irradiation. Patients transplanted without total body irradiation who received central nervous system irradiation were also at higher risk (adjusted HR: 3.39; P=0.02). Patients irradiated or transplanted at older than 10 years of age had a lower risk (adjusted HR: 0.61; P=0.02). Thyroid malignancy was found in 26 patients (5.2%). Among them, two patients had never received any type of irradiation: alkylating agents could also promote thyroid cancer. The cumulative incidence of thyroid malignancy was 9.6% (95% CI: 6.0-15.0) at 20 years. Women were at higher risk than men (adjusted HR: 4.74; P=0.002). In conclusion, thyroid complications are frequent among patients who undergo transplantation after total body irradiation and those who received prior central nervous system irradiation. Close monitoring is thus warranted for these patients. Clinicaltrials.gov identifier: NCT 01756599.

Effect of cancer treatment on hypothalamic-pituitary function

The past 30 years have seen a great improvement in survival of children and young adults treated for cancer. Cancer treatment can put patients at risk of health problems that can develop many years later, most commonly affecting the endocrine system. Patients treated with cranial radiotherapy often develop dysfunction of the hypothalamic-pituitary axis. A characteristic pattern of hormone deficiencies develops over several years. Growth hormone is disrupted most often, followed by gonadal, adrenal, and thyroid hormones, leading to abnormal growth and puberty in children, and affecting general wellbeing and fertility in adults. The severity and rate of development of hypopituitarism is determined by the dose of radiotherapy delivered to the hypothalamic-pituitary axis. Individual growth hormone deficiencies can develop after a dose as low as 10 Gy, whereas multiple hormone deficiencies are common after 60 Gy. New techniques in radiotherapy aim to reduce the effect on the hypothalamic-pituitary axis by minimising the dose received. Patients taking cytotoxic drugs do not often develop overt hypopituitarism, although the effect of radiotherapy might be enhanced. The exception is adrenal insufficiency caused by glucocorticosteroids which, although transient, can be life-threatening. New biological drugs to treat cancer can cause autoimmune hypophysitis and hypopituitarism; therefore, oncologists and endocrinologists should be vigilant and work together to optimise patient outcomes.

Secondary adrenal insufficiency in an infant after intrathecal triple chemotherapy

Intrathecal triple chemotherapy (ITT) with hydrocortisone, methotrexate, and cytarabine is commonly used in treatment of pediatric acute leukemias. While prolonged systemic administration of corticosteroids is known to suppress the hypothalamic-pituitary-adrenal axis, there have been no reports describing this effect following administration of ITT. We present an infant with relapsed acute myelogenous leukemia who developed clinically significant central adrenal axis suppression following six doses of ITT over 3 weeks, proven by corticorelin stimulation test. As multiple pediatric leukemia protocols incorporate ITT, particularly in infants, we feel that ITT should be considered as a potential source of adrenal axis suppression.

Prevalence and risk factors of radiation-induced growth hormone deficiency in childhood cancer survivors: a systematic review

BACKGROUND

Growth hormone deficiency (GHD) is usually the first and most frequent endocrine problem occurring after cranial radiotherapy (CRT). The aim of this systematic review was to evaluate the existing evidence of the prevalence and risk factors of radiation-induced GHD in childhood cancer survivors.

METHODS

MEDLINE, EMBASE and CENTRAL were searched for studies reporting on radiation-induced GHD in childhood cancer survivors. Information about study characteristics, prevalence and risk factors was abstracted and the quality of each study was assessed. A meta-regression analysis was performed.

RESULTS

The prevalence of radiation-induced GHD was estimated in 33 studies. Most studies had methodological limitations. The prevalence varied considerably between 0% and 90.9%. Selecting only the studies with adequate peak GH cut-off limits (<5 microg/L) resulted in 3 studies. In these studies the prevalence ranged from 29.0% to 39.1%, with a pooled prevalence of 35.6%. Higher CRT dose and longer follow-up time have been suggested to be the main risk factors of GHD by studies included in this review. The meta-regression analysis showed that the wide variation in the prevalence of GHD could be explained by differences in maximal CRT dose.

CONCLUSIONS

GHD is a frequent consequence after CRT in childhood cancer survivors. The prevalence of radiation-induced GHD ranged from 29.0% to 39.1% when selecting only studies with adequate peak GH cut-off limits. Higher CRT dose and longer follow-up time are the main risk factors. More well-designed studies are needed to accurately estimate the prevalence of GHD and to define the exact CRT threshold dose.

Fertility of female survivors of childhood cancer: a report from the childhood cancer survivor study

PURPOSE

This study was undertaken to determine the effect, if any, of treatment for cancer diagnosed during childhood or adolescence on fertility.

PATIENTS AND METHODS

We reviewed the fertility of female participants in the Childhood Cancer Survivor Study (CCSS), which consisted of 5-year survivors, and a cohort of randomly selected siblings who responded to a questionnaire. Medical records of all members of the cohort were abstracted to obtain chemotherapeutic agents administered; the cumulative dose of drug administered for several drugs of interest; and the doses, volumes, and dates of administration of all radiation therapy.

RESULTS

There were 5,149 female CCSS participants, and there were 1,441 female siblings of CCSS participants who were age 15 to 44 years. The relative risk (RR) for survivors of ever being pregnant was 0.81 (95% CI, 0.73 to 0.90; P < .001) compared with female siblings. In multivariate models among survivors only, those who received a hypothalamic/pituitary radiation dose > or = 30 Gy (RR, 0.61; 95% CI, 0.44 to 0.83) or an ovarian/uterine radiation dose greater than 5 Gy were less likely to have ever been pregnant (RR, 0.56 for 5 to 10 Gy; 95% CI, 0.37 to 0.85; RR, 0.18 for > 10 Gy; 95% CI, 0.13 to 0.26). Those with a summed alkylating agent dose (AAD) score of three or four or who were treated with lomustine or cyclophosphamide were less likely to have ever been pregnant.

CONCLUSION

This large study demonstrated that fertility is decreased among female CCSS participants. The risk factors identified may be utilized for pretreatment counseling of patients and their parents.

Leptomeningeal cancer in the pediatric patient

The treatment and prophylaxis of leptomeningeal leukemia and lymphoma in children has dramatically improved disease control and long-term survival. However, the treatment of other leptomeningeal cancers has been less successful and the neurologic morbidity associated with central nervous system-directed therapy has a significant long-term impact on quality of life. Further research is critical to identify new therapeutic strategies for children with or at high risk for leptomeningeal cancer.

Long-term effects of radiation therapy on cognitive and endocrine function in children with leukemia and brain tumors

BACKGROUND

As the number of long-term survivors of childhood cancer has grown, it has become increasingly clear that central nervous system therapy may have serious long-term effects on cognition and endocrine function. These complications have been studied most extensively in children with brain tumors and leukemia.

REVIEW SUMMARY

Children with acute lymphoblastic leukemia previously treated with cranial irradiation are at risk for cognitive decline. Chemotherapy-only regimens, which rely on high-dose frequently administered methotrexate, are also associated with producing cognitive dysfunction. Children irradiated for brain tumors are even more vulnerable. Risk factors include perioperative morbidity, young age, large-volume high-dose cranial irradiation, supra-tentorial location of tumor, moyamoya syndrome, and leukoencephalopathy. Cognitive decline is progressive over at least a decade. The most common radiation-induced endocrinopathies are hypothyroidism and growth hormone deficiency. Treatment effects on growth are multifactorial and include growth hormone deficiency,spinal shortening, precocious puberty, undetected hypothyroidism,and poor nutrition. Fifty percent to 80% of children treated with craniospinal radiation for brain tumors will experience growth failure. In hopes of reducing neurotoxicity, current treatments limit the dose and volume of radiation while adding chemotherapy. Results have not been uniformly positive, however, and may increase toxicity in some cases.

CONCLUSIONS

The standard of care in 2004 is that children who have been treated for brain tumors and leukemia should be monitored for cognitive and endocrine dysfunction. Until effective non-neurotoxic treatment is identified, long-term effects assessments are essential to maximize the quality of life of survivors of childhood cancer.

Hypopituitarism as a consequence of brain tumours and radiotherapy

Radiation-induced damage to the hypothalamic-pituitary (h-p) axis is associated with a wide spectrum of subtle and frank abnormalities in anterior pituitary hormones secretion. The frequency, rapidity of onset and the severity of these abnormalities correlate with the total radiation dose delivered to the h-p axis, as well as the fraction size, younger age at irradiation, prior pituitary compromise by tumour and/or surgery and the length of follow up. Whilst, the hypothalamus is the primary site of radiation-induced damage, secondary pituitary atrophy evolves with time due to impaired secretion of hypothalamic trophic factors and/or time-dependent direct radiation-induced damage. Selective radiosensitivity in the neuroendocrine axes with the GH axis being the most vulnerable to radiation damage accounts for the high frequency of GH deficiency, which usually occurs in isolation following irradiation of the h-p axis with doses less than 30 Gy. With higher radiation doses (30-50 Gy), however, the frequency of GH insufficiency substantially increases and can be as high as 50-100%, and TSH and ACTH deficiency start to occur with a long-term cumulative frequency of 3-6%. Abnormalities in gonadotrophin secretion are dose-dependent; precocious puberty can occur after radiation dose less than 30 Gy in girls only, and in both sexes equally with a radiation dose of 30-50 Gy. Gonadotrophin deficiency occurs infrequently and is usually a long-term complication following a minimum radiation dose of 30 Gy. Hyperprolactinemia, due to hypothalamic damage leading to reduced dopamine release, has been described in both sexes and all ages but is mostly seen in young women after intensive irradiation and is usually subclinical. A much higher incidence of gonadotrophin, ACTH and TSH deficiencies (30-60% after 10 years) occur after more intensive irradiation (>70 Gy) used for nasopharyngeal carcinomas and tumours of the skull base and following conventional irradiation (30-50 Gy) for pituitary tumours. Radiation-induced anterior pituitary hormone deficiencies are irreversible and progressive. Regular testing is mandatory to ensure timely diagnosis and early hormone replacement therapy to improve linear growth and prevent short stature in children cured from cancer, and in adults preserve sexual function, prevent ill health and osteoporosis and improve the quality of life.

Thyroid function in survivors of childhood acute lymphoblastic leukaemia: the significance of prophylactic cranial irradiation

OBJECTIVE

Focus on long-term side-effects after cancer therapy in childhood has become of the utmost importance. The hypothalamic-pituitary thyroid (HPT) axis is exposed to irradiation when some children are treated for acute lymphoblastic leukaemia (ALL) with prophylactic cranial irradiation (CIR). Whether this treatment causes hypofunction of the HPT axis remains controversial.

DESIGN

We measured plasma levels of total T3 (T3), total T4 (T4) and TSH before stimulation with TRH and plasma levels of TSH, 30 and 150 minutes after stimulation with TRH in 95 patients in first continuous remission of childhood ALL.

PATIENTS

Patients diagnosed with ALL before the age of 15 years between 1970 and 1991 and who were in first continuous remission and off treatment for at least one year were studied. The children were aged between 0.5 and 14.8 years (median: 3.9) at diagnosis of ALL. Thyroid function was assessed between 1.2 and 18.3 years (median: 7.6) after completion of therapy.

MEASUREMENTS

We measured T4 levels before, and compared TSH levels before and after, stimulation with TRH in patients who were treated with prophylactic CIR (15-24 Gy) (n = 38) (CIR group) with patients who were treated with chemotherapy only (n = 57) (non-CIR group).

RESULTS

We found that T3 and T4 levels were normal in all individuals (excluding the women who were on oral contraceptives). The median time from end of treatment to time at follow-up was 9.1 years in the non-CIR group vs. 4.2 years in the CIR group (P < 0.001), and the effect on follow-up time was significant (P = 0.04). It was estimated that just after irradiation, the TSH levels before and 30 and 150 minutes after TRH stimulation was 49% lower in the CIR group; however, after 4.0 years, TSH levels were not significantly different between the two groups. Although within normal limits, the T4 levels were significantly higher in the CIR group compared to the non-CIR group (P = 0.003). It was estimated that, just after the end of treatment, T4 was 19.9% higher in the CIR group. However, in the CIR group, the T4 level decreased significantly over time with -1.5% per year (P = 0.025), while the difference in the non-CIR group was not significant. There was no correlation between T4 and TSH levels and sex, age at diagnosis, age at the end of treatment or age at follow-up.

CONCLUSIONS

We conclude that, in our cohort of survivors of childhood ALL, prophylactic cranial irradiation of the central nervous system did not have an adverse effect on hypothalamo-pituitary-thyroid function within a median follow-up time of 8 years.

Neoplastic meningitis: diagnosis and treatment considerations

Neoplastic meningitis is an increasingly recognized complication of advanced metastatic cancer and, if left undiagnosed or untreated, is characterized by rapid neurologic deterioration and death. Thus, the diagnosis and treatment of neoplastic meningitis present challenges for the clinical oncologist. The diagnosis of neoplastic meningitis is based on clinical signs and symptoms, laboratory analysis of cerebrospinal fluid to determine cell count and cytology, and analysis of neuroimaging studies for evidence of leptomeningeal or cranial nerve enhancement. Once diagnosed, conventional treatment regimens may include radiotherapy combined with systemic or intrathecal chemotherapy, often with the antimetabolites cytarabine and/or methotrexate. However, the prognosis for neoplastic meningitis secondary to an underlying solid tumor or recurrent leukemia is poor with conventional treatment regimens. Therefore, novel agents for intrathecal administration, including DepoCyttrade mark, mafosfamide, and topotecan, or novel therapeutic approaches, including conjugated monoclonal antibodies and immunotoxins or gene therapy, are currently under investigation. Such new agents and therapeutic approaches will facilitate the development of effective treatment strategies and will ultimately improve the outcome for patients with this devastating disease. This article provides an overview of the approaches to the diagnosis, evaluation, and treatment of neoplastic meningitis.

Growth and growth hormone secretion in children with cancer treated with chemotherapy

OBJECTIVE

To evaluate the effect of chemotherapy on growth and growth hormone (GH) secretion.

METHODS

We analyzed growth and GH secretion in 60 children in complete remission after treatment by chemotherapy and surgery for malignant solid tumors. None of them received cranial radiotherapy. Growth hormone reserve was assessed by at least two stimulation tests (clonidine, L-dopa, growth hormone-releasing hormone). In 12 children the reserve of GH pretreatment was also evaluated.

RESULTS

Growth hormone deficiency (GHD) was observed in 27 of 60 patients (45%). At diagnosis, mean standing height was +0.23 +/- 0.11 standard deviation score (SDS) in the GHD group and +0.16 +/- 0.10 SDS in the non-GHD group. After chemotherapy, mean standing height in the GHD group was -0.28 +/- 0.15 SDS and -0.14 +/- 0.11 in the non-GHD group (p < 0.05), and the growth rate was +0.13 +/- 0.07 SDS in the GHD group and +0.22 +/- 0.18 SDS in the non-GHD group. For a mean follow-up of 30 months, the mean standing height was -0.46 +/- 0.29 SDS in the GHD group and -0.24 +/- 0.16 SDS for the non-GHD group (p < 0.05), and the growth rate was -0.27 +/- 0.19 SDS in the GHD group and -0.16 +/- 0.12 SDS in the non-GHD group (p < 0.05). The GH response to clonidine was significantly less than that found with the other stimuli. There was correlation between the dose intensity of some drugs and the subsequent GH response to stimulation tests. The GHD group was found to have received significantly higher doses of actinomycin D than the non-GHD group (p < 0.05). Growth impairment and GHD were not found to be correlated with duration of treatment and follow-up, tumor type, sex, or age.

CONCLUSIONS

Chemotherapy as the sole form of treatment in children with cancer interferes with growth. The observed impairment of growth depends, at least in part, on a GHD related to chemotherapy. The growth rate in conjunction with the GH response to clonidine provides a sensitive measure of GHD associated with chemotherapy.

Thyroid function in children treated for acute lymphoblastic leukemia

To determine the late effects of treatment on thyroid function in children who survive acute lymphoblastic leukemia, we assessed plasma levels of thyroid hormones in 24 children (15 girls and 9 boys) who had received combination of chemotherapy along with 18-24 Gy of irradiation to the cranium. The children were aged between 1 and 10.5 years (mean 3.1) at diagnosis and thyroid status was investigated between 1.3 and 13 years (mean 6.8) after completion of therapy. Six children showed a low peak of plasma thyroid stimulating hormone (TSH), after stimulation with thyrotrophin-releasing hormone (TRH). Three children showed a low basal plasma TSH concentration. Serum levels of thyroxine (T4, fT4) and triiodothyronine (T3, fT3) were normal in all patients. The frequency of thyroid hypofunction (low peak response of TSH to TRH) was more common in children receiving 24 compared to 18 Gy cranial irradiation (50% vs 14%; odds ratio = 7) and those who had completed therapy more than 5 years ago (31.3% vs 12.5%, odds ratio 3.18) although no significant association could be found (95% IC: 0.27-65.8 and 0.24-90 respectively). Because of the low mean age at diagnosis of our population no significant association could be found between children younger than 3 years of age at diagnosis and thyroid hypofunction (odds ratio = 0.14; 95% IC: 0.01-1.48). We conclude that treatment for acute lymphoblastic leukemia including cranial irradiation may lead to TRH/TSH dysfunction and therefore long term survivors should be followed for a long period after completion of therapy.

Prevalence of obesity in young adults with acute lymphoblastic leukemia

We studied the hormonal pattern of nine patients with acute lymphoblastic leukemia. The patients were treated with standard therapeutic regimens. They were overweight by a mean of 52% at the end of the consolidation treatment, and this persisted after a follow-up of 2 years. The only endocrine alteration observed was a moderate decrease in serum testosterone levels in male patients. The other parameters studied were in the normal range. We conclude that prolonged treatment with high doses of corticosteroids, which have a depressive effect on metabolism, was responsible for the obesity.

The effects of adjuvant chemotherapy on growth in children with medulloblastoma

BACKGROUND

Current therapy for children with medulloblastoma includes craniospinal radiation therapy (CSRT) with or without adjuvant chemotherapy. The difference in growth of children after the two different therapeutic modalities is unknown.

METHODS

The growth of 38 prepubertal children who survived medulloblastoma was reviewed retrospectively. Fifteen of these patients received CSRT alone; 23 received chemotherapy in addition to the radiation therapy.

RESULTS

The average growth velocity of all patients with medulloblastoma during the 4 years of the study was below the mean for age and sex in all patients except one. Most patients grew at velocities more than two standard deviations below the mean. The overall growth of children who received chemotherapy in conjunction with CSRT was significantly worse than the growth of those who received only CSRT. The children who received chemotherapy showed little or no improvement in growth velocity by year 4; those who did not receive chemotherapy had some improvement.

CONCLUSIONS

These findings suggest that chemotherapy potentiates the deleterious effects of radiation on growth.

Changes in the approach to central nervous system tumors in childhood

Current approaches to children with brain tumors are in a state of evolution. Currently, 50% of children with all types of brain tumors may be expected to survive 5 years. Therefore, the goals of neuro-oncology have broadened to include improved survival and improved quality of life. This article reviews changes in therapy that have altered survival as well as changes in therapy as a consequence of increasing recognition of complications and toxicity of treatment.

Impaired pubertal growth in acute lymphoblastic leukaemia

The growth of 182 patients who were long term survivors of childhood acute lymphoblastic leukaemia was retrospectively analysed. All remained in first remission and were treated with either 1800 or 2400 cGy of cranial irradiation. None had been treated with either testicular or spinal irradiation. Ninety three (51 boys, 42 girls) were treated with 2400 cGy and 89 (42 boys, 47 girls) were treated with 1800 cGy cranial irradiation. All patients were treated with standard chemotherapy including intrathecal methotrexate in similar dose regimens in either group. Mean age (SD) at diagnosis in the group treated with 2400 cGy was 4.8 (2.6) years and mean age in the group treated with 1800 cGy was 6.5 (3.3) years. Mean height SD score at diagnosis in the 2400 cGy group was +0.29 and final height achieved was -0.63. Mean height SD score at the start of treatment in the group treated with 1800 cGy was +0.40 and mean final height was -0.53. There was a similar reduction in height SD score in both groups during the pubertal growth spurt. The decrement in height SD score was greater when treatment was administered at less than 7 years of age in either dose regimen, both in prepubertal and pubertal growth. However, the decrease in height SD score was found to be greater in girls than boys. There was a trend in both sexes for the onset of puberty to be at a younger age with a lower treatment dose of radiotherapy. However, in girls treated with the lower dose regimen there was a significant reduction in the mean age of onset of puberty which was 9.9 years. Our data suggest that girls treated at less than 7 years of age have a severe impairment of pubertal growth, which is probably a combination of the dual endocrinopathy of premature puberty and growth hormone insufficiency.

Extramedullary relapse in childhood leukemia

As long-term survival of children with leukemia is increasing, the prophylaxis of extramedullary leukemia has become a more important part of treatment. We studied the pattern of occurrence of extramedullary leukemia in a retrospective review. This review included a total of 2,317 childhood leukemia patients aged 15 years or less who had been treated at 38 institutes in Japan between 1976 and 1985. Extramedullary leukemia developed in 386 of 1,724 ALL patients (22.4%) and 63 of 544 patients with ANLL (16.3%). Among the ALL patients, CNS-L was the most common form and was observed in 315 cases (81.6%), followed by testicular leukemia in 89 (23.0%). In the case of ANLL, the most common form of extramedullary leukemia was CNS-L (45 cases, 71.4%), followed by cutaneous leukemia in 10 cases (15.9%). In addition, leukemia of the lymph nodes, ovaries, bones, kidneys and eyes was observed in 7, 5, 5, 4 and 4 cases, respectively. The survival rate of ALL patients with CNS-L was 40.1% for isolated relapse and 2.7% for bone marrow relapse, and no more deaths occurred after 6 years from relapse. The survival rate of patients with testicular leukemia was 40.1% for isolated relapse and 5.9% for complicating bone marrow relapse, and no deaths occurred after 7 years from relapse. Cutaneous leukemia tended to occur late in older children with ALL and early in infants with ANLL, and all these patients died. Infiltration into the kidney was observed in 4 patients, all of whom died. More than 75% of patients died after isolated relapse of leukemia of the bones, ovaries, lymph nodes and eyes.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term consequences of CNS treatment for childhood cancer, Part II: Clinical consequences

Survival of children with brain tumors has improved over the past 20 years due in part to advances in surgery, radiation, and most recently chemotherapy. The long-term adverse effects of radiation and chemotherapy on these children is the subject of this report. In Part I, we reviewed the pathologic consequences of radiation, including leukoencephalopathy, radiation necrosis, and radiation myelopathy as well as the oncogenic effects of both radiation and chemotherapy. Part II addresses the long-term consequences of radiation and chemotherapy on intellectual and endocrine function. Risk factors for the development of both endocrinopathies and intellectual dysfunction include age at the time of radiation, volume and dose of radiation, site of tumor, and use of adjuvant chemotherapy, in particular methotrexate. Early recognition of these complications and treatment, where indicated, will measurably improve the quality-of-life of children treated for brain tumors. The national cancer groups are currently attempting to limit these long-term adverse effects by taking risk factors into account when formulating new treatment regimens.

Diabetes insipidus 9 years after cessation of therapy for acute lymphoblastic leukemia

A case of a 16-year-old who developed diabetes insipidus (DI) 9 years after cessation of therapy for ALL is reported. Because hereditary and traumatic factors are excluded as a cause of DI in this patient, possible explanations may be leukemic CNS relapse, secondary brain tumor, primitive idiopathic DI, and late sequelae of CNS radiochemotherapy.

Long-term endocrine toxicity of myeloablative treatment followed by autologous bone marrow/blood derived stem cell transplantation in patients with malignant lymphohematopoietic disorders

The effect of myeloablative treatment with autologous bone marrow transplantation (ABMT)/autologous blood derived stem cell transplantation (ABSCT) in patients with acute leukemias or lymphomas was studied in 32 adult patients with a mean observation time of 15.8 months after transplantation. The conditioning regimen consisted of hyperfractionated total-body irradiation (TBI) and high-dose cyclophosphamide or the cyclophosphamide, carmustine, and etoposid (CBV) regimen. In all of the female patients, we observed primary ovarian failure requiring estradiol replacement therapy. In all of the male patients, testosterone levels were normal but follicle stimulating hormone (FSH) levels were increased, suggestive of germinal aplasia which was proved by semen analysis in several patients. In contrast to the reports of other groups, we did not find any abnormalities in thyroid function, most likely because TBI was hyperfractionated. Moderate toxicity to the adrenal cortex was noticed and was more pronounced in women than in men. Our results are similar to findings reported after allogeneic bone marrow transplantation, with the exception of normal thyroid function in our patients. These results should be taken into consideration when counseling patients about the long-term consequences of myeloablative treatment. Cryopreservation of semen should be offered to men before myeloablative treatment. Estrogen replacement should be initiated after transplantation in women to prevent adverse effects of long-term ovarian failure.

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.

Height of children off therapy after acute lymphoblastic leukemia

A total of 290 children off therapy after acute lymphoblastic leukemia, in continuous complete remission for at least 2 years, were evaluated for height at the onset of the disease and at the most recent clinical visit (median time after suspension of treatment 4 years 4 months, range 2 years-11 years 3 months). All patients had been treated with multidrug schedules; intrathecal drugs had been given to 84% of the patients for prevention of CNS involvement, associated with radiotherapy. The height percentiles at the most recent examination were shifted downward significantly compared with the expected pattern (p less than 0.001). The effect on stature was much more marked in girls, with a reduction of height percentiles at most recent examination from expected and from diagnosis; in males there was a reduction from diagnosis to latest follow-up, but the values were within the limits of normal. The short stature was mostly observed in pubertal girls and in patients who had undergone radiotherapy.

Thyroid function in children after cytostatic treatment for acute leukemia

Sixty-one children were examined for thyroid dysfunction as an adverse late effect after cessation of antileukemic treatment. The aim of the study was to contribute to clarifying which types of therapy can cause this endocrine disorder. Our treatment protocols do not include cranial irradiation as CNS prophylaxis, but we give relatively intensive intrathecal methotrexate treatment. The results indicate that this cytostatic regimen alone does not cause thyroid dysfunction as an adverse late effect.

Long-term sequelae of cancer treatment on the central nervous system in childhood

Increasing numbers of children with cancer, including those with acute lymphocytic leukemia and medulloblastoma, are experiencing long-term disease control. As survival increases, so does the recognition that the treatment used to prolong survival may have significant detrimental effects on the central nervous system (CNS). Because of the slow replication rate of most constituents of the CNS, these effects tend to be delayed. Radiotherapy, and to a lesser extent, chemotherapy (primarily methotrexate) have been implicated in the causation of such sequelae. The pathogenesis of CNS damage is only partially understood and evidence suggests that direct effects on intracranial endothelial cells and brain white matter and immunologic mechanism play a role. A spectrum of clinical syndromes may occur, including radionecrosis, necrotizing leukoencephalopathy, mineralizing microangiopathy with dystrophic calcification, cerebellar sclerosis and spinal cord dysfunction. The two most common forms of sequelae are neuropsychological and neuroendocrinologic damage. The frequency, degree of and etiology of neurocognitive dysfunction is less than completely elucidated. Radiotherapy has been implicated as the major cause of damage, but the relationship between radiotherapy and the type of damage caused and the volume and dose of radiotherapy and degree of cognitive damage is unclear. Cognitive deficits are progressive in nature. Younger children are more likely to suffer the severest damage; but no patient of any age is free of risk of damage. Growth hormone impairment is the most common form of neuroendocrinologic dysfunction. There is increasing evidence that children with cancer who are long-term survivors are at increased risk for the development of secondary CNS tumors; possibly due, in part, to previous treatment. Much work needs to be done to characterize the sequelae which may occur, develop means of earlier detection, investigate ways to ameliorate sequelae and devise less toxic treatment.

Intermediate dose methotrexate in childhood acute lymphoblastic leukemia resulting in decreased incidence of testicular relapse

Six hundred thirty-four children with acute lymphoblastic leukemia (ALL) were randomized to receive sanctuary therapy consisting of either cranial irradiation (CRT) plus intrathecal (IT) methotrexate (MTX) or three courses of intermediate-dose methotrexate (IDM) plus intrathecal methotrexate. Two hundred sixty-six male patients achieved a complete response and were evaluable for the effects of prophylactic therapy on the duration of remission. There was one isolated testicular relapse (0.8%) in the IDM group compared with 14 (10%) in the CRT group. The incidence of testicular relapse was significantly lower in the patients treated with IDM (P less than 0.001). High plasma levels of MTX achieved during the 24-hour infusions may result in increased penetration of MTX into the interstitium of the testes, thus allowing for the eradication of sequestered leukemic cells and preventing the emergence of drug resistance resulting from exposure to sublethal concentration of MTX.