Hyperleukocytosis and extreme hyperleukocytosis, defined as initial white blood cell counts greater than 100 × 10⁹/L and 200 × 10⁹/L, respectively, have been associated with unfavorable outcomes. This study aimed to determine the early complications and survival outcomes of childhood leukemia patients with hyperleukocytosis. The medical records of 690 children newly diagnosed with acute leukemia between January 1998 and December 2017 were retrospectively reviewed. The Kaplan–Meier method and log-rank test were used to assess and compare the survival outcomes. Multivariate Cox proportional hazards regression was used to determine associated risk factors for overall survival. We found that 16.6% of 483 childhood acute lymphoblastic leukemia (ALL) patients and 20.3% of 207 childhood acute myeloid leukemia (AML) patients had hyperleukocytosis at diagnosis. ALL patients with hyperleukocytosis had more early complications than those without hyperleukocytosis (p < 0.05). Among the ALL group, the 5-year overall survival rate for those with hyperleukocytosis was significantly lower than for those without hyperleukocytosis (37.2% vs. 67.8%, p < 0.0001), while the difference was not statistically significant in the AML group (19.0% vs. 30.2%, respectively, p = 0.26). Hyperleukocytosis (hazard ratio [HR]: 2.04), extreme hyperleukocytosis (HR: 2.71), age less than 1 year (HR: 3.05), age greater than 10 years (HR: 1.64), and male sex (HR: 1.37) were independently associated with poorer overall survival in childhood ALL patients. Extreme hyperleukocytosis (HR: 2.63) and age less than 1 year (HR: 1.82) were independently associated with poorer overall survival in AML patients. Hyperleukocytosis was associated with adverse survival outcomes in childhood leukemia.

There is limited information on vitamin D deficiency among childhood cancer survivors (CSS), especially in tropical countries. The aims of this study are to determine the prevalence and risk factors for vitamin D deficiency in CCSs. This study was conducted at the long-term follow-up clinic for CCSs at Prince of Songkla University, Songkhla, Thailand. All CCSs who were followed up between January 2021 and March 2022 were enrolled. Demographic data, dietary dairy intake, average weekly duration of outdoor activities, total 25-hydroxyvitamin D [25(OH)D] levels, parathyroid hormone levels, and blood chemistry were collected. A total of 206 CCSs with a mean age at follow-up of 10.8 ± 4.7 years were included. The prevalence of vitamin D deficiency was 35.9%. Female gender (odds ratio (OR): 2.11, 95% CI: 1.08–4.13), obesity (OR: 2.01, 95% CI: 1.00–4.04), lack of outdoor activities (OR: 4.14, 95% CI: 2.08–8.21), and lower dietary dairy intake (OR: 0.59, 95% CI: 0.44–0.80) were independent risk factors for vitamin D deficiency. Vitamin D deficiency was common in CCSs and associated with female gender, obesity, lack of outdoor activities, and lower dietary dairy intake. Regular 25(OH)D screening should be established in long-term care to identify those who require vitamin D supplements.

Although there have been advances in treating pediatric patients with acute myeloid leukemia (AML) in developed countries, outcomes in low- to middle-income countries remain poor. The goal of this study was to investigate the outcomes in children with AML who were treated at a tertiary care center in Thailand. We divided the study into 4 research periods based on the chemotherapy protocols employed. The 5-year probabilities of event-free survival (pEFS) rates for periods 1-4 were 19.0%, 20.6%, 17.4%, and 37.3% (p value = 0.32), while the 5-year probabilities of overall survival (pOS) rates were 19.0%, 24.7%, 18.7%, and 42.5% (p value = 0.18), respectively. The multivariable model indicated an improvement in 5-year pOS between periods 1 and 4 (p value = 0.04). Age, white blood cell count, and study period were significant predictors of survival outcomes. The pOS of AML patients improved over time, increasing from 19.0% to 42.5%.

Tumor lysis syndrome (TLS) in childhood leukemia was assessed retrospectively in 252 patients in a single tertiary center in Thailand during 2009-2019. Fifty-one (20.2%) developed TLS during their induction chemotherapy; 60.7% (31/51) were spontaneous TLS and 47% (24/51) developed clinical TLS. The predictive score model consisted of white blood cell (WBC) count more than 50,000 cells/mm3, glomerular filtration rate less than 90, and aspartate transaminase more than 44 units/L. The TLS development rates were 11.1%, 46.2%, and 78.5% in the low, intermediate, and high-risk groups, respectively. Death during the first induction phase in patients with TLS was significantly higher than in the patients without TLS. However, the 5-year overall survival rates for the children with and without TLS were not significantly different.

Aims: Von Willebrand disease (VWD) is an inherited haemostatic disorder with a wide range of bleeding phenotypes based on von Willebrand factor (VWF) levels. Multiple assays including VWF gene analysis are employed to correctly diagnose VWD and its subtypes. However, data on VWF mutations among Southeast Asian populations are lacking. We, therefore, aimed to explore genetic variations in Thai patients with type 2 and type 3 VWD by whole exome sequencing (WES). Methods: In this multicentre study, Thai patients with type 2 and type 3 VWD, according to the definitions and VWF levels recommended by the international guidelines, were recruited. WES was performed using DNA extracted from peripheral blood in all cases. The novel variants were verified by Sanger sequencing. Results: Fifteen patients (73% females; median age at diagnosis 3.0 years) with type 2 (n=12) and type 3 VWD (n=3) from 14 families were enrolled. All patients harboured at least one VWF variant. Six missense (p.Arg1374Cys, p.Arg1374His, p.Arg1399Cys, p.Arg1597Trp, p.Ser1613Pro, p.Pro1648Arg) and one splice-site (c.3379+1G>A) variants in the VWF gene were formerly described. Notably, six VWF variants, including three missense (p.Met814Ile, p.Trp856Cys, p.Pro2032Leu), one deletion (c.2251delG) and two splice-site (c.7729+4A>C, c.8115+2delT) mutations were novelly identified. Compound heterozygosity contributed to type 2 and type 3 VWD phenotypes in two and one patients, respectively. Conclusions: Type 2 and type 3 VWD in Thailand demonstrate the mutational variations among VWF exons/introns with several unique variants. The WES-based approach potentially provides helpful information to verify VWD diagnosis and facilitate genetic counselling in clinical practice.

Studies on the long-term treatment outcomes of childhood acute lymphoblastic leukemia (ALL) in resource-limited countries are scarce. The purpose of this study was to assess the evolution of survival outcomes of pediatric ALL in a tertiary care center in Thailand over a 40-year period. We retrospectively reviewed the medical records of pediatric patients who were diagnosed with ALL and treated at our center between June 1979 and December 2019. We classified the patients into 4 study periods depending on the therapy protocol used to treat the patients (period 1: 1979–1986, period 2: 1987–2005, period 3: 2006–2013, and period 4: 2014–2019). The Kaplan–Meier method was used to determine overall and event-free survival (EFS) for each group. The log-rank test was used to identify statistical differences. Over the study period, 726 patients with ALL were identified, 428 boys (59%) and 298 girls (41%), with a median age at diagnosis of 4.7 years (range: 0.2–15 years). The study periods 1, 2, 3, and 4 had 5-year EFS rates of 27.6%, 41.6%, 55.9%, and 66.4%, and 5-year overall survival (OS) rates of 32.8%, 47.8%, 61.5%, and 69.3%, respectively. From periods 1 to 4, both the EFS and OS rates increased significantly (p <. 0001). Age, study period, and white blood cell (WBC) count were all significant prognostic indicators for survival outcomes. The OS of patients with ALL treated in our center improved significantly over time from 32.8% in period 1 to 69.3% in period 4.