Relationship of growth hormone deficiency and leukemia

[Safety aspects of treatments with hrGH]

Recombinant human growth hormone (hrGH) has been used for treatment of growth hormone deficient children over 20 years and it can be considered to have an excellent safety profile. The main international surveys show few adverse drug reactions reported, specially in idiopathic growth hormone deficiency and in idiopathic short stature. With regard to cancer risk or tumor recurrence, it seems that there is no greater risk with hrGH treatment in comparison to general population. The idiopathic intracranial hypertension is a rare condition, but its incidence is higher in patients with chronic renal failure. The adverse events are rare in patients treated with hrGH, but these patients should be carefully monitored, specially those with pharmacologycal doses or with another clinical condition of greater risk.

Growth hormone treatment and cancer risk

Increasing numbers of children receive growth hormone (GH) to treat a range of growth disorders, including those rendered GH deficient (GHD) by tumors or their treatment. Young persons with persistent growth hormone deficiency (GHD) and adults with severe GHD are also eligible to receive GH treatment. As in vitro and in vivo studies and epidemiologic observations provide some evidence that the GH--insulin like growth factor-I (IGF-I) axis is associated with tumorigenesis, it is important to assess, in practice, the incidence of tumors related to GH treatment. Reassuringly, surveillance studies in large cohorts of children and in smaller cohorts of adults indicate that GH is not associated with an increased incidence of tumor occurrence or recurrence. Nevertheless, all children who have received GH, in particular cancer survivors and those receiving GH in adulthood, should be in surveillance programs to assess whether an increased rate od late-onset and rare tumours may occur.

Hormones and Supplements: Do They Work?: Use of Growth Hormone for Prevention or Treatment of Effects of Aging

Decreases in growth hormone (GH) and insulin-like growth factor-I, estrogen deficiency in women, diminished testosterone in men, and loss of lean body mass, increased fat, and other changes consistent with hormone deficiencies occur during aging. Treatment of nonelderly GH-deficient adults with recombinant human GH (rhGH) improves body composition, muscle strength, physical function, and bone density, and reduces blood cholesterol and cardiovascular disease risk, but is often accompanied by carpal tunnel syndrome, peripheral edema, joint pain and swelling, gynecomastia, glucose intolerance, and possibly increased cancer risk. Reports that rhGH augments lean body mass and reduces body fat in aged individuals increased use of rhGH to delay aging effects. However, clinically significant functional benefits, prolongation of youth, and life extension have not been demonstrated. Moreover, marketing of rhGH and other hormone supplements largely ignores adverse effects. Until more research has better defined the risk/benefit relationships, treatment of elderly individuals with rhGH should be confined to controlled research studies.

Growth hormone deficiency and related disorders: insights into causation, diagnosis, and treatment

Advances in molecular biology have led to the identification of mutations within several novel genes associated with the phenotype of isolated growth hormone deficiency, combined pituitary hormone deficiency, and syndromes such as septo-optic dysplasia. Progress has also been made in terms of the optimum diagnosis of disorders of stature and their treatment. The use of growth hormone for the treatment of adults with growth hormone deficiency and conditions such as Turner's syndrome, Prader-Willi syndrome, intrauterine growth restriction, and chronic renal failure has changed the practice of endocrinology, although cost-benefit implications remain to be established.

Endocrine complications in pediatric patients with acute lymphoblastic leukemia

Endocrine complications of therapy for acute lymphoblastic leukemia (ALL) are common and are potentially debilitating both during and after therapy. Growth velocity slows during therapy for ALL, especially during the first year; however, children who do not receive cranial irradiation usually reach normal adult height. While growth hormone deficiency generally occurs in patients who have received 24Gy of cranial irradiation, it may also develop in those treated with lower doses (18Gy) of cranial radiation or with only high-dose methotrexate. Obesity commonly occurs during therapy and persists after completion of therapy. Osteopenia can occur early during therapy for ALL and can persist for many years. Adrenal insufficiency should be suspected in any child who has recently received glucocorticoid therapy, and stress doses of steroid should be administered in the event of metabolic stress. Screening of urine is useful for early detection of hyperglycemia during therapy with glucocorticoids and L-asparaginase. The syndrome of inappropriate secretion of anti-diuretic hormone is usually associated with vincristine therapy and may be aggravated by concurrent use of azole antifungals. Finally, patients who have received 18 or 24Gy of cranial irradiation may have clinical or subclinical deficiencies of thyroid hormones.

Late effects of childhood cancer therapy

This study reviews the common long-term sequalae of childhood cancer and its therapy. It discusses the clinical and research challenges posed by such late effects. The authors address related topics of late effects research and clinical care, methodological issues, barriers and directions for the future.

Leukemia in children treated with growth hormone

An association between treatment with growth hormone (GH) and the development of leukemia was described in 1988. This perceived association is best explained by the fact that there are more children with GH deficiency (GHD) with risk factors predisposing them to leukemia than in the general population. These factors include previous cancers and their treatment, as well as co-existing conditions such as Down, Bloom and Fanconi syndromes. Examination of large databases of GH-treated individuals shows that GH-treated patients without these risk factors do not have an increased incidence of leukemia.

Increased incidence of neoplasia in patients with pituitary adenomas. The Pituitary Study Group

OBJECTIVE

The goal of our study was to determine the rate of neoplasms in patients with other pituitary adenomas (non-functioning and prolactinomas) in comparison with acromegaly which is known to favour the development of neoplasia.

DESIGN AND PATIENTS

We reviewed clinical records for 220 patients with acromegaly, 151 patients with non-functioning pituitary adenoma (NF) and 98 patients with prolactinomas. Incidence rates of cancer for patients with pituitary tumours were calculated per person-years of follow-up study. These rates were then compared with sex and age adjusted incidence rates reported by National Tumour Registry. An internal control group of 163 subjects with a non-neoplastic condition, i.e. Graves' disease followed chronically in the same clinic was also studied. The ratios observed to expected were expressed as standardized incidence rates (SIR). The only significant difference between the acromegalic and other pituitary tumours patients was in hypopituitarism, present in 18.2% (acromegaly) 47% (NF) and 18.6% (prolactinomas).

RESULTS

Twenty-three malignant tumours were registered in 19 acromegalics (1 Hodgkin disease, 1 myelogenous leukaemia, 1 lymphocytic leukaemia, 3 papillary thyroid carcinomas, 1 ovarian carcinoma, 2 colorectal carcinoma, 1 renal cell carcinoma, 4 cervical carcinoma, 2 skin cancers, 2 pancreatic carcinoma, 4 breast carcinoma, 1 bladder carcinoma). Three acromegalics harboured two malignancies. Patients with acromegaly had a 3.39-fold increased rate of malignant tumours compared with the general population and a 3.21-fold increased rate compared with our internal control group. Eleven malignant tumours were found in patients with NF-pituitary adenomas and 2 in prolactinoma patients (1 lymphoma, 1 multiple myeloma, 1 colonic cancer, 1 renal cell cancer, 1 stomach cancer, 2 lung cancers, 1 cervix carcinoma, 1 breast cancer, 1 testicular carcinoma and 3 melanoma). Patients with NF pituitary adenomas had a 3.91-fold increased rate of malignant tumours compared with the general population and 4.07-fold increase compared with the internal control group. Patients harbouring prolactinomas did not have an increased incidence rate of malignancy compared with the general population or our internal controls. Female patients with acromegaly and male patients with NF-pituitary adenoma had higher incidences of neoplasia.

CONCLUSION

We have demonstrated that the overall incidence of malignant tumours in patients with non-functioning pituitary adenomas and acromegaly is significantly higher than expected for general population and for our internal control group.