Evaluation of bone minerals density in children treated for acute lymphoblastic leukemia

Introduction and purpose: Acute lymphoblastic leukemia (ALL) is the most common malignancy of childhood. Survival rates from leukemia have increased tremendously in recent years. As survival increased, the incidence of long-term side effects increased as well. Decrease in bone mineral density (BMD) is a common effect, leading to bone pain and pathological fractures. Dual energy x-ray absorptiometry (DEXA) is used in patient follow-up, since the effects of chemotherapeutics used in the treatment on bone density cannot be evaluated in direct X-rays. In this study; The aim of this study was to evaluate the bone mineral density of patients whose leukemia treatment was completed. Materials and Methods: The study included 50 patients in the pediatric age group who were diagnosed with leukemia in Dicle University Faculty of Medicine, Department of Pediatric Hematology and Oncology between January 1, 2010 and December 31, 2020 and whose active chemotherapy treatment was completed within the last year. The complaints of the patients at admission to the hospital, laboratory values at the time of diagnosis, risk group of the patients, laboratory values after treatment and bone mineral densities were evaluated with DEXA. Results: Fifty patients (26 boys, 24 girls) who finished ALL treatment at least one year ago were included in the study. The mean age at diagnosis of the patients was found to be 70.94 ± 38.84 months. Fatigue (n=14 patients, 28%) was the first among the complaints at admission to the hospital, and osteoarthralgia (n=10 patients, 20%) was the second. Ninety percent (n=9 patients) of the patients with osteoarthralgia were female. Patients were considered to have osteopenia below -1 according to the Z score (n= 24). The duration of treatment for patients with osteopenia was 25.94 ± 2.5 months, and the duration of treatment for 26 patients without osteopenia was 26.26 ± 2.83 months, and no significant difference was observed (p: 0.700). Our patients included in the study; They were classified as low, medium and high risk groups according to the laboratory parameters at the time of diagnosis, the percentage of blasts in the peripheral smear on the 8th day, and the bone marrow blast rate on the 15th and 33rd days. The highest patient density was found in the MRI group, with a rate of 58% (n=29). When the Z score in DEXA was compared according to the risk group of the patients, no significant difference was found between SRG-MRI and HRG (p=.239). Biochemical parameters Ca, Phosphorus, Mg, PTH, ALP, BMI, and DEXA Z scores after treatment were compared between patients who applied with the complaint of osteoarthralgia and those who applied with other complaints. Complaining of osteoarthralgia at the time of diagnosis A significant difference was found in the PTH values of the patients who did not have osteoarthralgia complaints after the treatment (p=.020). In addition, post-treatment calcium significant difference was found in the values (p=,036). However, no difference was found between the bone mineral densities measured after the treatment (p= ,497). Vitamin D deficiency was detected in 80% of the patients (n=40 patients). The mean vitamin D value was determined as 18.91 µg/L. Among the treatment risk groups, vit. D levels were compared, vitamin D levels were lower in patients in the HRG group and a significant difference was found (p=.001). Discussion and Conclusion: In some studies, it has been reported that patients with ALL have low bone mineral density (BMD) after treatment and an increased risk of fracture. In our study, we did not observe a decrease in fractures and BMD at the end of the treatment in our patients. However, it is very important to follow the patients closely in terms of long-term side effects of the drugs used in the treatment and vitamin D deficiency. Patients should be offered vitamin D support and a calcium-rich diet. Evaluation in terms of bone mineral density after treatment will prevent the morbidity of the patients.