Final height and puberty in 40 patients after antileukaemic treatment during childhood

Height deficit during and many years after treatment for acute lymphoblastic leukemia in children: a review

There are conflicting data on the incidence and severity of height deficits in children with acute lymphoblastic leukemia (ALL). This is probably due to: (1) collection of data in different phases of treatment; (2) differences in chemotherapeutic regimens; (3) inclusion or not of children who had received cranial irradiation (CRT); (4) limited numbers of patients; (5) relative numbers of prepubertal and pubertal children; (6) different ways of measuring growth deficits. Twenty-five papers published between 1987 and 2006 were reviewed. These reveal that (1) chemotherapy always causes some height reduction during treatment regardless of whether additional CRT is given; (2) catch-up growth occurs immediately after cessation of treatment; (3) intensive chemotherapy alone significantly decreases height in the long-term but to a lesser extent than with additional CRT; (4) young children develop more severe height loss; (5) girls are reported to have greater height deficits but confounding factors have not been adequately considered; (6) late growth hormone (GH) deficiency has been detected in many children, mostly in those who had CRT; (7) GH replacement therapy seems to be effective. ALL relapse in GH-treated children is not more common than in those not treated with GH.

Leptin assessment in acute lymphocytic leukemia survivors: role of cranial radiotherapy?

Leptin has been hypothesized to play a role in the development of obesity in leukemia survivors, particularly those who have received cranial radiotherapy. This cross-sectional study evaluated the relationship between leptin levels and body mass index (BMI) in a sample of 26 acute lymphocytic leukemia survivors of both sexes, treated with and without cranial irradiation, aged 7.6 to 17 years, at a mean 3.4+/-2.0 years off treatment. There were significantly more males among the irradiated group (P<0.001), even though no differences were encountered in pubertal stage (P=1.000), BMI standard deviation score (mean+/-SD) (0.68+/-1.00 vs. 1.19+/-0.78; P=0.164), or leptin concentrations (17.01+/-17.04 vs. 23.3+/-13.4; P=0.309). Nonetheless, there was a positive correlation between the natural logarithm of leptin and BMI standard deviation score [t(22)=2.348, P=0.028], however, no differences were recorded among irradiated and nonirradiated patients [F(2,22)=0.384, P=0.685]. When this relationship was compared between sexes, a significant difference was encountered [F(2,22)=4.907, P=0.017], with males having the strongest association (R(2)males=65.5%, R(2)females=34.7%). Leptin is a reliable adiposity index as it strongly correlates with BMI. Overall, the current data suggest that cranial irradiation did not play a role upon this relationship; however, sex differences influenced positively this correlation.

Longitudinal growth and risk factors for growth deficiency in children treated for acute lymphoblastic leukemia

BACKGROUND

Growth deficit has been reported as a frequent complication of the treatment of acute lymphoblastic leukemia (ALL).

PROCEDURE

Longitudinal analysis of the growth of 129 children, from a total of 351 cases diagnosed between 1987 and 1994 in Brazil, was determined. Height data were converted into standard deviation Z scores. Only girls younger than 10 and boys younger than 12 years old at diagnosis were included. Patients were treated according to a German BFM-83 based protocol. Fifty-eight children received 18 Gy cranial irradiation, four 12 Gy, and two 24 Gy. Patients were aggregated into five non-excluding groups according to availability of height data at diagnosis, during the treatment, at the end of it, and several years after; 35 children reached their final height.

RESULTS

Height deficit at the end of the therapeutic treatment was evident (P < 0.0001). Catch-up occurred 1 year after stopping treatment (P = 0.016). At the last follow-up, over 5 years after the end of treatment (n = 83) or at final height (n = 35), impressive height deficits were recorded (P < 0.0001 for both end points). Multivariate analysis demonstrated that growth impairment was more severe in children younger than 4 years at diagnosis and in those who received cranial irradiation. No significant effect of gender was observed. Children who were treated solely with chemotherapy also had significant height loss.

CONCLUSIONS

Treatment of ALL in children is associated with growth deficit during the treatment and several years after it, affecting the final height negatively, particularly in patients younger than 4 and in those who received cranial irradiation.

Effects of chemotherapy on bone metabolism and skeletal growth

In recent years there has been a significant increase in both acute and chronic toxicity associated with the more successful but now highly intensive chemotherapy (CT) regimens used to treat childhood cancers. The incidence of childhood cancers coincides with periods of rapid skeletal development. Consequently, short stature and osteoporosis are important long-term effects in adult survivors. Clinical data indicate that the effects of CT, including glucocorticoids, on final height are due to direct effects of these drugs on the skeleton. The multiple modes of action of CT drugs suggest a complex and diverse influence on chondrocytes, extracellular matrix and bone cells. However, only limited data demonstrate these direct effects on the proliferative capacity of growth plate chondrocytes and on key steps of endochondral ossification, the multistep process that determines rate and extent of long bone growth. Endochondral ossification requires coordinated maturation, proliferation and differentiation of growth plate chondrocytes leading to hypertrophic cells which eventually undergo apoptosis to leave a cartilaginous scaffold that is mineralized prior to the laying down of new bone. Disruption of the physiological cellular activity of growth plate chondrocytes and/or bone cells result in skeletal growth disturbances. Thus, CT drugs which disrupt normal cell division may manifest their effects on the growth plate as either a reduction in cell number and/or the loss of functional integrity of extracellular matrix. Histological and cell kinetic studies, using in vivo and in vitro models of long bone growth, are essential to increase our understanding of the cellular mechanisms involved and to finally determine how the individual growth potential might be maintained during treatment for childhood cancers.

Disturbance of pubertal development after cancer treatment

Chemotherapy and irradiation to the hypothalamic-pituitary-gonadal axis given for childhood cancer carry with them a risk of endocrine late effects. These treatment modalities are part of the treatment of common oncological diseases in childhood such as acute lymphoblastic leukaemia, brain tumours, Hodgkins lymphoma and solid tumours outside the central nervous system. Cranial irradiation of a prepubertal child can induce early or even precocious puberty, particularly in girls. Hypogonadotrophic hypogonadism may develop at a later stage. Irradiation of the gonads, as e.g. part of total body irradiation before bone marrow transplantation, will most likely cause gonadal failure and late, incomplete or absent puberty in girls. Many boys will experience a normal pubertal development except for small testes. Alkylating agents given for a variety of childhood cancers, are gonadotoxic. After high doses of these drugs, girls are at great risk of developing ovarian failure, whereas boys will usually go through puberty normally. Many children receive a combination of several treatment modalities, which complicates the prediction of pubertal development. Control and management of children with cancer at risk of having a disturbance of puberty is difficult and requires detailed knowledge of endocrinology as well as oncology. This chapter reviews the common treatments for the most frequent childhood cancers, the known effects of the therapy on pubertal development and provides outlines of control and management.

Adult height and age at menarche in childhood cancer survivors

The aim of this study was to assess the long-term effects of cancer treatments on adult height and age at menarche in survivors of various types of childhood cancer. 285 childhood cancer survivors (161 men and 124 women), at least 18 years old and having been off treatment for at least 5 years, were examined. The effects of cranial (CrRT) and craniospinal irradiation (CrSpRT), other treatments and age at diagnosis on adult height and age at menarche were investigated. Patients who did not receive CrRT or CrSpRT, reached normal adult heights. However, a significant reduction in adult height was observed in men and women treated with CrRT or CrSpRT, especially if the treatment was given at the age of 8 years or younger. In girls, CrRT resulted in a significantly earlier menarche, compared with the Dutch population. Chemotherapy, radiation dose and age at menarche did not affect adult height. The relative risk (RR) of attaining an adult height below the 3rd percentile (20% 49/244) of the study population) was 6 times increased (RR=6.4; 95% confidence interval (CI) 1.46-28.52) after CrSpRT, 4 times (RR=4.2; 95% CI 1.81-9.63) after Crth and 5 times (RR=51; 95% CI 2.23-11.59) when irradiation was administered at the age of 8 years or younger. CrRT and CrSpRT and age at treatment are the main determinants of short stature in male and female childhood cancer survivors.

Bone turnover and growth during and after continuing chemotherapy in children with acute lymphoblastic leukemia

Children treated for acute lymphoblastic leukemia may develop reduced bone mineral density during treatment, but there is little information on the mechanisms involved. In a prospective, longitudinal study on 15 children with ALL, we undertook serial measurements of markers of bone and collagen turnover, insulin-like growth factor (IGF)-I and its binding proteins (IGFBPs)-3 and -2 during the second year of continuing chemotherapy. In eight patients we also measured lower leg length by knemometry. Height SD scores, lower leg length velocity, IGF-I, and markers of bone collagen turnover did not differ significantly from healthy children. However, bone alkaline phosphatase, a marker of the differentiated osteoblast, was lower (mean SD score, -0.64; p < 0.0001), whereas procollagen type III N-terminal propeptide (P3NP, a marker of soft tissue collagen turnover; mean SD score, +0.93, p < 0.05), IGFBP-3 (mean SD score, +0.76; p < 0.01), and IGFBP-2 (mean SD score, +1.24, p = 0.01) were all higher than in healthy children. IGFBP-3 decreased during episodes of afebrile neutropenia (p < 0.05). Within 3 mo after completion of treatment, bone ALP increased in all eight patients, but collagen markers showed little change. IGFBP-2 returned to normal posttreatment, but P3NP and IGFBP-3 remained significantly elevated compared with healthy children (mean SD scores, +1.51 and +1.36, respectively; p < 0.01). We conclude that continuing chemotherapy was associated with normal growth and bone collagen turnover but enhanced soft tissue collagen turnover. Bone bone alkaline phosphatase was low throughout treatment, which suggests impaired osteoblast differentiation resulting from a direct effect of chemotherapy on bone. Although the effect was reversible, the long-term implications for bone health in survivors remain uncertain.

Cranial irradiation of female rats causes dose-dependent and age-dependent activation or inhibition of pubertal development

Cranial irradiation in prepubertal children with leukemia or brain tumors can lead to precocious or in high doses to late puberty. To unravel the underlying mechanisms, we developed a rat model with selective cranial Co60-irradiation technique. Infantile (12-16 d old) or juvenile (21-23 d old) female Sprague-Dawley rats received a single dose of 4, 5, 6, 9 or 2 x 9 Gy (at days 21 and 23). Each group consisted of 7-20 animals. High radiation doses (9 Gy and more) caused retardation of sexual development, whereas low radiation doses (5 or 6 Gy) led to accelerated onset of puberty in 20% of infantile irradiated rats animals as determined by vaginal opening. Interestingly, at peripubertal age (postnatal day 32-34), 5 or 6 Gy infantile irradiated rats had significantly higher serum LH levels stimulated by GnRH and estradiol levels (p < 0.05). 2 x 9 Gy irradiated rats had at the age of 3 mo a marked growth retardation and significantly lower GH levels than the controls (p < 0.05) whereas prolactin, FSH, TSH, T4, and corticosterone levels were comparable with controls. These studies demonstrate that the GnRH-pulse generator is very radiosensitive as precocious activation occurred after low dose irradiation (5 or 6 Gy) of infantile rats without any other endocrine disorder. High radiation doses (9 or 2 x 9 Gy) induced retardation of sexual maturation and later on growth hormone deficiency. Moreover this model of cranial irradiation seems to be suitable to study the molecular mechanisms of radiation induced pubertal changes.

Effects of a third intensification block of chemotherapy on bone and collagen turnover, insulin-like growth factor I, its binding proteins and short-term growth in children with acute lymphoblastic leukaemia

Children with acute lymphoblastic leukaemia (ALL) have reduced bone turnover caused by the disease itself and early intensive chemotherapy, but the effects of later chemotherapy using different drug combinations are uncertain. We report here a longitudinal study on 9 children with ALL randomised to receive an additional third intensification block of chemotherapy, compared with 9 children receiving continuing chemotherapy over the same period. During third intensification, bone alkaline phosphatase, procollagen type I C-terminal propeptide, the carboxyterminal propeptide of type I collagen, procollagen type III N-terminal propeptide and lower leg length all decreased in response to dexamethasone, then returned to (but not beyond) baseline levels after dexamethasone was stopped and other drugs started. These changes were unrelated to circulating insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3 or IGFBP-2. In all children, bone alkaline phosphatase remained below the population mean throughout. We conclude that dexamethasone decreased bone and soft tissue turnover, probably through direct effects on target tissues. The postdexamethasone phase of third intensification and continuing chemotherapy had no major deleterious effect on collagen turnover, but there was evidence of continuing suboptimal bone mineralisation.