Background: ACTH deficiency (ACTHD) is a potentially life-threatening condition observed in many childhood survivors of intracranial. Time from tumor diagnosis and therapy to development of ACTHD cannot be ascertained from previous studies. This lack of knowledge has led to annual surveillance using low-dose ACTH stimulation testing (LDST) for 1015 years following completion of therapy.
Objective and hypotheses: To identify the incidence and timing to ACTHD onset to allow development of an effective screening strategy among brain tumor survivors.
Method: We performed a retrospective chart review of 77 children diagnosed with primary brain tumor in the optic (OP) or suprasellar (SS) regions, between 2002 and 2012. The outcome of interest was ACTHD, defined as peak serum cortisol <18 μg/dl 20 min after 1 μg/m2 i.v. ACTH. Peak cortisol >20 μg/dl was defined as normal while 1820 μg/dl was indeterminate. For random cortisol levels, ACTHD was defined as cortisol ≤12.9 μg/dl drawn at 07000900 h. A level ≥13 at any time of the day was considered normal.
Results: Among this subset of 77 patients (52% female, mean age (±S.D.) 6.1±4.5 years), 69% (53) had OP (mean age 4.8±3.9 years) and 31% (24) had SS (mean age 9.0±4.4 years). ACTHD was present in 6 (14.3% of those who had any ACTH testing, 7.8% of all patients), however 43% (33) have not had any testing. Two additional patients had indeterminate results. Of those with ACTHD, 33% (2/6) had OP. Among the 25% (19/77) who underwent cranial irradiation, 2 (11%) developed ACTHD. The time to onset of ACTHD from tumor diagnosis was 1.3 years (range: −0.02, 4.26) (n=6), and from irradiation −0.2 and 0.75 years (n=2). Among those who underwent LDST, n=36, the time from diagnosis to initial test was 2.2 years (−0.1 to 8.2) and from therapy was 1.4 years (−3.3 to 6.1). Concurrent endocrinopathies were found in 83% of those with ACTHD vs 61% of those without ACTHD.
Conclusion: For patients with optic pathway or suprasellar tumors, monitoring for ACTHD should be done at the time of diagnosis, then annually thereafter. A follow up screening for ACTHD should be done 46 months after completion of cranial irradiation therapy.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology