The Assessment of the Hypothalamic-Pituitary-Adrenal Axis After Oncological Treatment in Pediatric Patients with Acute Lymphoblastic Leukemia

OBJECTIVE: Oncologic treatment can affect the adrenal glands, which in stressful situations may lead to life threatening adrenal crisis. The aim of the study was to assess adrenal function in pediatric acute lymphoblastic leukemia (ALL) survivors and to identify the best markers for this assessment. METHODS: Forty-three ALL survivors, mean age 8.5±3.6 years and 45 age and sex-matched healthy controls were recruited to the study. ALL patients were assessed once within five years following oncological treatment completion. Fasting blood samples were collected from all participants to measure: fasting blood glucose (FBG); cortisol; aldosterone; plasma renin activity (PRA); dehydroepiandrostendione-sulfate (DHEA-S); and adrenocorticotropic hormone (ACTH). Moreover, diurnal profile of cortisol levels and 24-hour urinary free cortisol (UFC) were assessed. ALL survivors underwent a test with 1 ug of synthetic ACTH. RESULTS: The study revealed lower level of PRA (1.94±0.98 ng/mL/h vs 3.61±4.85 ng/mL/h, p=0.029) and higher FBG (4.6±0.38 mmol/L vs 4.41±0.39 mmol/L, p=0.018) in the ALL group compared to controls. UFC correlated with evening cortisol (p=0.015, r=0.26), midnight cortisol (p=0.002, r=0.33), and DHEA-S (p=0.004, r=0.32). UFC also correlated with systolic and diastolic blood pressure (p=0.033, r=0.23 and p=0.005, r=0.31, respectively). The ACTH test confirmed impaired adrenal function in 4/43 ALL survivors (9%). Two of the patients who needed permanent hydrocortisone replacement had low UFC, midnight cortisol and DHEA-S levels. CONCLUSION: These results highlight the importance of reviewing adrenal gland functionality after chemo/radiotherapy in ALL survivors. DHEA-S proved to be a good marker to assess the adrenal glands after oncological therapy. Post-treatment disturbances of the adrenal axis could be associated with metabolic complications.