Final height and growth hormone secretion after bone marrow transplantation in children

Total body irradiation as part of conditioning regimens in childhood leukemia-long-term outcome, toxicity, and secondary malignancies

Background

Total body irradiation (TBI) is an established part of conditioning regimens prior to stem cell transplantation in childhood leukemia but is associated with long-term toxicity. We retrospectively analyzed survival, long-term toxicity, and secondary malignancies in a pooled cohort of pediatric patients (pts.) treated with the same TBI regimen.

Methods

Analyzed were 109 pts. treated between September 1996 and November 2015. Conditioning treatment according to EBMT guidelines and the ALL SCTped 2012 FORUM trial consisted of chemotherapy (CT) and TBI with 2 Gy b.i.d. on 3 consecutive days to a total dose of 12 Gy. Median follow-up was 97.9 months (2–228 months).

Results

Overall survival (OS) in our cohort at 2, 5, and 10 years was 86.1, 75.5, and 63.0%, respectively. Median survival was not reached. Long-term toxicity developed in 47 pts. After chronically abnormal liver and kidney parameters in 31 and 7 pts., respectively, growth retardation was the most frequent finding as seen in 13 pts. Secondary malignancies were rare (n = 3).

Conclusion

TBI-containing conditioning regimens in pediatric stem cell transplantation (SCT) are highly effective. Efforts to replace TBI- with CT-containing regimens have only been successful in subgroups of pts. Although we could show long-term toxicity in 43% of pts., overall survival was 63% at 10 years. Still, long-term effects such as growth retardation can permanently impact the pts.’ quality of life and functioning. Along with new substances, efforts should be undertaken to optimize TBI techniques and accompany the treatment by systematic follow-up programs beyond 5 years to improve detection of rare events.

The impact of childhood cancer and its treatment on puberty and subsequent hypothalamic pituitary and gonadal function, in both boys and girls

Childhood cancer survivors (CCS) are at an increased risk of endocrine disorders. Disorders of the hypothalamic-pituitary-gonadal (HPG) axis are a particular concern because of their impact on pubertal development and future fertility and may be of central (hypothalamic or pituitary damage) or primary (gonadal) origin. Hypogonadism may present as pubertal disorders during adolescence and subsequent infertility in adulthood but should be anticipated to ensure appropriate surveillance is in place to address these issues at an appropriate age. Those at risk of HPG axis dysfunction include those with tumours primarily affecting the hypothalamus, pituitary or gonads themselves or due to their treatment with surgery, radiotherapy and chemotherapy. CCS who have had cranial irradiation of more than 30 Gy are at risk of gonadotrophin deficiency. Those who have had gonadotoxic chemotherapy, especially alkylating agents or radiotherapy to the gonads are at risk of primary gonadal failure. HSCT survivors who have had chemotherapy and total body irradiation are at risk of primary gonadal failure but may also have gonadotrophin deficiency. Understanding those at risk is essential to appropriate counselling and long-term follow-up. This chapter gives an overview on the impact of childhood cancer and its treatment on puberty, gonadal function and fertility in childhood cancer survivors.

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.

Endocrine complications in long-term survivors after allogeneic stem cell transplant

As survival rates continue to increase after allogeneic stem cell transplant (allo-SCT), the associated long-term complications of transplant need to be taken into consideration. Here, we review the endocrine and metabolic complications associated with transplant survivors, including diabetes, dyslipidemia, hypertension, cardiovascular disease, hypogonadism, vitamin D deficiency, osteoporosis, thyroid disease, adrenal dysfunction, and pituitary disorders, and provide a brief summary of evaluation and treatment of these conditions.

High incidence of fatty liver and insulin resistance in long-term adult survivors of childhood SCT

Overweight/obesity among adult survivors of childhood SCT has been considered to be predictive of eventual development of metabolic abnormalities. Fatty liver is increasingly recognized as a major cause of liver-related morbidity and mortality in the general population. However, the real incidence of fatty liver in adult survivors of SCT has not been fully elucidated. We determined whether adult survivors are at risk for overweight/obesity, metabolic abnormalities and fatty liver and whether these risks are associated with cranial radiotherapy (CRT) before SCT. Among the 51 patients (30 males), only two male patients were overweight/obese at the last evaluation. On the other hand, 9 male (30%) and 15 female (71%) patients were underweight. Fatty liver was diagnosed in 11 male (37%) and 10 female (48%) patients during the follow-up period, although patients who had fatty liver did not tend to be overweight/obese. Significantly more patients who received CRT before SCT developed fatty liver with insulin resistance than those who did not (P<0.05). Even patients who are not overweight/obese may develop fatty liver and metabolic abnormalities. We recommend that healthcare professionals recognize these risks and give life-long attention to detecting, preventing and treating late complications after SCT.

Growth and Endocrine Function in Long-term Adult Survivors of Childhood Stem Cell Transplant

The number of long-term surviving stem cell transplant (SCT) recipients has increased steadily, and attention has now extended to the late complications of this procedure. The objective of this study was to investigate relationship among growth and endocrine functions in long-term adult survivors of childhood SCT. The inclusion criteria of this study were survival at least 5 yr after SCT and achievement of adult height. Fifty-four patients (39 males) fulfilled these criteria and were included in this study. Growth was mainly evaluated by height standard deviation score (SDS) and individual longitudinal growth curves. Among the 54 patients, those that received SCT before 10 yr of age showed significantly greater reductions in changes in height SDS (mean –1.75, range –4.80 to –0.10) compared with those that received SCT at or after 10 yr of age (mean –0.50, range –1.74 to 1.20; P<0.001). The mean loss of height for all patients who received SCT during childhood was estimated to be approximately 1 SDS/6.5 yr (r=0.517). Individual longitudinal growth curves indicated that a significant growth spurt was absent in severe short stature patients during the pubertal period without severe endocrine dysfunctions including GH deficiency. The incidence of growth disorder in long-term adult survivors depends on the age at SCT and whether they received radiation therapy. Life-long follow-up is necessary for survivors to detect, prevent and treat the late endocrine complications in SCT survivors.

Endocrinological analysis of 122 Japanese childhood cancer survivors in a single hospital

With recent improvements in the diagnosis and treatment of cancer, the number of childhood cancer survivors (CCSs) has been increasing in Japan. The importance of quality of life during the lifetime of CCSs has now been recognized, and the late effects of cancer treatments are essential and important issues. In this study we analyzed the endocrinological abnormalities of CCSs by retrospectively evaluating 122 outpatients (62 males and 60 females) who had been referred from pediatric oncologists to our follow-up clinic among 151 CCSs attending our hospital more than two years after their cancer treatment. Follow-up duration varied from 2 to 30 (median 8.0) years. Their average age was 17.3 (range 4-36, median 17.0) years, and 38 patients (31.1%) reached adulthood. Endocrinological abnormalities were found in 82 (67%) of 122 survivors. Gonadal dysfunction was observed in 60 patients (49%). Thirty-nine patients (32%) were short or grew at a slower rate. Twenty-six patients (21%) showed thyroid dysfunction. Other abnormalities were as follows: obesity in 20 patients (16%), leanness in 10 (8%), central diabetes insipidus in 11 (9%) and adrenocortical dysfunction in 9 (7%). Low bone mineral density was observed in 41 (42%) of 98 patients evaluated. These endocrinological abnormalities were caused by the combined effects of cancer itself and various treatments (chemotherapy, radiation therapy, surgery, and hematopoietic stem cell transplantation). Lifetime medical surveillance and continuous follow-up are necessary for CCSs, because treatment-related complications may occur during childhood and many years after the therapy as well. Endocrinologists should participate in long-term follow-up of these survivors in collaboration with pediatric oncologists.

Late effects after stem cell transplantation (SCT) in children--growth and hormones

Stem cell transplantation (SCT) has established itself as a very successful therapy in often otherwise unbeatable disorders. In a subset of children and adolescents there are, however, late effects, often as a combination of the underlying disorder, its primary treatment and subsequent SCT. In children and adolescents, disorders of growth and the endocrine system have been observed to occur frequently. The assurance of normal growth, puberty, fertility and thyroid function--including the prevention of secondary malignancies--is of utmost importance for the overall success of treatment and the maintenance of quality of life. This, however, requires a systematic and structured follow-up programme for patients after SCT. Patients and their families need to be made familiar with this concept early and physicians need to understand that such a system must be implemented as part of a comprehensive care.

Impact of polymorphisms of human beta-adrenergic receptor gene on changes in height during growth hormone treatment

The aim of this study was to investigate the occurrence of polymorphisms of the beta-adrenergic receptor gene in short children and to evaluate the possible influence of the polymorphisms on changes in height and obesity index in response to GH treatment. Of the 75 children enrolled in the study, 40 completed at least 5 years of GH treatment. The genotype distribution of the beta2 and 3-adrenergic receptor polymorphisms in the study population did not differ significantly from those reported in non-obese subjects. There were no significant differences in the SD score for height at any given time-point between the group with and without the Trp64Arg mutation of the beta3-adrenergic receptor gene. In relation to the Glyl6Arg polymorphism of the beta2-adrenergic receptor gene, the mean SD score for height increased significantly during GH treatment in children with Argl6Arg and Glyl6Arg. In those with Glyl6Gly, the score did not show any significant increase during all 5 years of GH treatment. In both the groups with and without the Trp64Arg mutation, the changes in obesity index did not reach statistical significance at any time-point. Only children with Glyl6Gly had a significantly higher baseline mean obesity index than those with Glyl6Arg. The index also decreased markedly from 21.9% to 5.8% in these children during the first 4 years of GH treatment. Thus, when the impact of the polymorphisms of these two receptor genes was studied simultaneously, it appeared that only the beta2-adrenergic receptor polymorphism had an important role to play in modulating the regulation of growth rate and energy expenditure in short children.