Objective: The survival rate of childhood leukemia has reached 80% with evolving treatment modalities over the last 30 years, which is followed by an increased incidence of treatment-related long-term side effects. This study, it was aimed to evaluate the endocrine late effects of chemoradiotherapy in childhood acute lymphoblastic leukemia (ALL).

Methods: Forty-eight patients with ALL treated at the University of Health Sciences Türkiye, İstanbul Kanuni Sultan Süleyman Training and Research Hospital, Clinic of Pediatric Hematology and Oncology between 1997 and 2007 with at least 5-year follow-up after the chemotherapy, were included.

Results: Endocrine side effects were detected in 48% (n=23) of the cases. The most common endocrine side effect was short stature in the group treated with cranial radiotherapy (CRT), and obesity in the group that did not receive CRT. The median height standard deviation score (SDS) of the subjects who reached the final height (FH) was significantly lower [-1.44 (-2.1)-(-0.53)] compared with the median height SDS of the subjects who did not reach the FH [-0.24 (-1.23)-(0.6)]. There was a positive correlation between height SDS and IGF1 SDS, IGFBP3 SDS, body mass index SDS, and advanced bone age in subjects who did not reach FH (r=0.511, p=0.018, r=0.530, p=0.014, r=0.499, p=0.021, r=0.599, p=0.08, respectively). Precocious puberty was found in one patient who received CRT, and hypergonadotropic hypogonadism was found in one patient who did not receive CRT. Twenty-three percent of the group received CRT and 35% of the group who did not receive CRT had overweight/obesity. Central hypothyroidism was detected in one case and subclinical hypothyroidism was detected in two cases.

Conclusion: Long-term endocrine side effects were observed in approximately half of the cases with childhood ALL. Children treated with chemoradiotherapy should have regular endocrine system evaluation and growth monitoring starting from the diagnosis until the growth is completed.

Keywords: Acute lymphoblastic leukemia, growth, late effects, puberty, obesity