Endocrine Abstracts

Somatotropin is essential not only for linear growth but also for important metabolic functions. Its deficiency is usually the first and most common endocrinopathy induced by cancer disease and its treatments, mainly cranial irradiation. Although somatotropin replacement therapy is safe and effective in promoting a better linear growth, studies of final height in childhood cancer survivors treated with somatotropin are limited. This study was performed to examine growth outcomes in these patients. A retrospective analysis was performed, through consultation of the clinical processes. We included all childhood cancer survivors treated with somatotropin in a pediatric endocrinology department, between 1988 and 2016. Statistical analysis was performed using SPSS v24. Were included 28 cancer survivors, 64.3% male. The median age at cancer diagnosis was 5.6 years and 60.7% had central nervous system tumors; 60.7% undertook surgery, 71.4% radiotherapy and 67.9% chemotherapy. Only 42.9% had IGF1 more than 2 SDS below the mean, being the most frequent criteria to investigate somatotropin deficiency the height velocity more than 3 SDS below the mean. There were concomitant endocrinopathies in 50% of patients. Somatotropin treatment was started at a median of 11.3 years. The initial height was −2.14 SDS and increased to −1.81 SDS by 1 year, −1.68 SDS by 2 years, and −1.56 SDS by 3 years with somatotropin treatment. There were differences between the initial height and by 1 year (P<0.001), by 1 and 2 years (P=0.006) and between initial and final height (P=0.025). Despite that, this patients’ adult height was significantly lower than the midparental height (P=0.006). The body mass index decreased, significantly in the first year of treatment (P=0.002). The initial IGF1 concentration was −2.02 SDS and increased significantly to 0.93 SDS by 1 year (P<0.001). The differences between chronological and bone age decreased throughout the treatment with a significant difference between the beginning and the third year of treatment (P=0.047). Median treatment duration was 4.0 years (min 6 months, max 11 years). Difference between adult height and midparental height was not associated with gender, group of tumor, concomitant endocrinopathies, age or puberty stage at beginning. We concluded that the improvement of linear growth was significant, mainly in the first year of treatment, but these patients did not achieve their genetic potential for height. The physicians must be aware and search for this endocrinopathy in this group of patients and treatment should be started as soon as possible.