HL is an oncological emergency in pediatric patients with acute leukemia. It has been shown that the risk of mortality increases when neurological/pulmonary leukostasis develops (2, 3). LP is recommended in leukostasis or when the WBC is elevated, but there is no definite consensus on the management of these patients. It has been suggested that LP should be performed when the WBC exceeds 400,000 cells/mm3 (2). However, other authors suggested that LP could not be applied to any patient, regardless of the WBC, since it could not be performed in this particular center and no patient loss was experienced, despite the inability to use LP (14). In the present study, the WBC of patients who underwent LP was > 300,000 cells/mm3 with one exception. In the exception, who had dyspnea, the WBC was 168,000 cells/mm3 when they underwent LP. When the patients who did not have LP were examined, the WBC was > 300,000 cells/mm3 in only two patients. When both the LP and non-LP groups were examined, no death was observed in the first month of follow-up and there were 32 (78.05%) patients in the non-LP group. In addition, after LP, the WBC decreased from a mean of 510,000 cells/mm3 to 65,000 cells/mm3, an decrease in the mean WBC of 87.3%, demonstrating the efficacy of LP. Although LP treatment appears effective and safe, treatment of HL is possible with only hydration support, administration of allopurinol/rasburicase, early initiation of treatment for the disease within the first 24 hours, and close clinical follow-up.
There are studies reporting that LP does not delay the duration of CT (1, 6). This is supported by the results of the present study, as there was no difference in the initiation time of CT, in patients who received LP versus those who did not.
Increasing age, male gender, and T-cell ALL phenotype are reported to be predictors for LP (2, 3, 8, 15). In our study, age, male gender, and T-cell ALL phenotype were associated with an increased probability of LP, in keeping with the literature.
The clinical symptoms of leukostasis increase the likelihood of requiring LP (3, 16). In our study, no neurological leukostasis was observed and LP was used in one patient with pulmonary leukostasis, but not to another patient. Both patients survived, but the patient who did not undergo LP required a 55-day stay in the PICU, while the patient who underwent LP only required a seven day stay in PICU. The WBC in these two patients was 202,000 cells/mm3 and 168,000 cells/mm3, respectively. It should be noted that the patient who did not undergo LP was an infant and was diagnosed with AML, which may also have had an effect on the prolongation of the length of stay in PICU.
Complications related to LP use have been reported, such as hemodynamic changes, electrolyte irregularities, bleeding due to anticoagulation use, and risks associated with central lines (4, 6). However, no significant complications were reported in the present study, as in similar previous studies (1, 6, 17).
A summary of the literature regarding LP results in children with HL who are admitted to the hospital with acute leukemia in Table 3. The common feature of all these studies is that the case group consisted of new diagnosis cancer patients in the pediatric age group. In these reports, LP results were investigated. According to the study results, LP is generally indicated as an effective and safe option.
Table 3
Literature review of LP results in childhood acute leukemia
Study- Year Number of cases Number of LP cases | Study Characteristics (diagnosis, reason for hospitalization) | Conclusion |
14 Gelen et al. 2022 61 case 0 LP | Childhood, Acute Leukemia, Hyperleukocytosis | LPh may be performed in patients with leukostasis, if it is not possible to start induction CT early. |
18Christakopoulos et al 2023 49 case 16 LP | Childhood, Acute Miyeloid Leukemia, Hyperleukocytosis | Compared with patients who received LP, the percentage decrease in leukocyte counts was greater among those who received CT (p = .02). No early deaths occurred. |
15 Nguyen et al. 2016. 53 case None | Childhood, Acute Lymphoblastic Leukemia, Hyperleukocytosis | The early morbidity and mortality commonly associated with hyperleukocytosis in children with newly diagnosed ALL can be avoided with contemporary supportive care and conservative management possibly obviating the need for costly and potentially dangerous leukapheresis. |
19Cuttner et al 1983 22 case 22 LP | Childhood, Acute Miyeloid Leukemia, Hyperleukocytosis | Greater than a 30% decrease in initial WBC was found to be an important predictor of response. |
20Greze et al 2014 7 case 7 LP | Childhood, Acute Leukemia, Hyperleukocytosis | LK is a well-tolerated procedure that can be safely performed with an experienced pediatric team even on the smallest children. |
21Yılmaz et al 2014 12 case 12 LP | Childhood, Acute Leukemia, Hyperleukocytosis | No patients developed any other problem related to the procedure. Our results showed that leukapheresis is a safe and effective procedure if performed by experienced staff. |
22Bruserud et al 2013 16 case 16 LP | Childhood, Acute Miyeloid Leukemia, Hyperleukocytosis | Previous studies in AML also support the conclusion that this is a safe and effective procedure for the treatment of a potentially life-threatening complication, but apheresis should always be combined with early chemotherapy. |
7Creutzig et al 2016 238 case None | Childhood, Acute Miyeloid Leukemia, Hyperleukocytosis | Our data confirm the high risk of bleeding/leukostasis in patients with hyperleukocytosis. LP shows a trend toward reduced early death rate due to bleeding/leukostasis |
LP: Leukapheresis.
In the management of patients with HL, prompt and coordinated intervention is required to assess the patient's risk and prevent complications. The effectiveness of LP treatment is usually temporary. The number of blasts in the peripheral circulation may increase rapidly shortly after the procedure. The standard treatment for patients with acute leukemia with HL is supportive therapy and induction CT, in addition to LP. To prevent rebound leukocytes and blasts, cytoreductive therapy, such as the use of hydroxyurea and/or induction CT, should be initiated rapidly.
The limitations of our study are the small cohort size and its retrospective design. Future works should consider looking prospectively at the role of leukapheresis in hyperleukocytic acute leukemia.