Leukemia is a group of malignant diseases of the bone marrow and lymphatic system. It involves the unrestricted proliferation of immature white blood cells in the blood-forming tissues of the body and invades normal cells that do not form solid tumor masses (Hockenberry & Wilson, 2018; Marcdante & Kliegman, 2019). Worldwide, leukemia is the most common malignant neoplasm in childhood, accounting for about one-fourth (25%) of all malignancies that arise in children under 20 years old (Al-Shamahy et al., 2021). Globally, it represents nearly 80% of all cancer diagnoses accounting for almost one out of three cancers (Siegel et al., 2019). In Egypt, according to the National Cancer Institute (NCI) at Cairo University, it accounts for almost one-third of newly diagnosed pediatric cancer cases with approximately four cases per 100.000 children annually (Rasekh et al., 2020).There are four main types of childhood leukemia. Acute lymphocytic leukemia (ALL) is the most prevalent type in children accounting for nearly three-quarters of leukemia cases and almost 26% of malignancies in children. It is primarily diagnosed in males rather than females (3:1 ratio), with a prevalent age of incidence between two to five years (Inaba & Pui, 2021; Malczewska et al., 2022). The hematopoietic tissue in the bone marrow is characterized by the overproduction of immature lymphocytes (Al-Shamahy et al., 2021). The specific etiology of leukemia has not yet been determined. However, many risk factors, mainly genetics, epigenetic lesions, ionizing radiation, other chemical and occupational factors, smoking, and some viral agents, have been implicated in the progression of leukemia. Unfortunately, the impact of leukemia in high-income countries is massive, leading to premature death in children, and high medical costs that affect the economic, social, and health well-being of the population (Inaba & Pui, 2021; Malczewska et al., 2022).

Treatment of leukemia involves the use of chemotherapy, radiotherapy, immune therapy, and surgery. The therapy can be single or combined (Yuliar et al., 2019). Chemotherapy is a crucial treatment for children with leukemia that is used to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing, while causing harmful side effect (Mohamed et al., 2022). Chemotherapy-Induced Nausea and Vomiting (CINV) are the most common catastrophic adverse effects of chemotherapy which hurt the quality of life of children and may even lead to refusal of the treatment regimen, ultimately resulting in death (Rajendran, 2016). It occurs shortly after the administration of chemotherapy with a prevalence between 54%-96% among children. Chemotherapy-induced nausea and vomiting are related to the stimulation of the chemo-receptor trigger zone, autonomic nervous system, peripheral and atrial mechanisms, and psychosocial factors (Miladinia et al., 2015).

Hence, CINV is classified as anticipatory, acute, and delayed nausea and vomiting based on the time of occurrence (Rajendran, 2016). Anticipatory CINV depicts nausea and vomiting happening before chemotherapy treatment as a conditioned response due to the incidence of CINV in previous cycles. Acute CINV happens within 24 hrs. of chemotherapy administration and acute vomiting is predominantly mediated by 5-HT3. Delayed CINV happens 24 hrs. to five days after chemotherapy administration and is primarily mediated by substance P binding to neurokinin 1 (NK1) receptors in the central nervous system (CNS) (Gupta et al., 2021).

Chemotherapy-induced nausea and vomiting can be managed by pharmacological and non-pharmacological methods. Nausea and vomiting remain a problem for children with leukemia undergoing chemotherapy despite receiving new antiemetic drugs (Lou et al., 2014). Additionally, there is clinical evidence showing that common chemotherapy treatment, even when supplemented with effective antiemetic medications, may still trigger nausea and vomiting. So, to limit CINV, it is necessary to combine non-pharmacological therapies with pharmacological methods for those children from the onset of treatment (Semerci et al., 2022).

Inhalation of high-quality natural essential oils such as peppermint may empirically be useful in controlling CINV through their effect on the central nervous system including the amygdala and hippocampus (Evans et al., 2018; Johnson et al., 2016). It is a safe, non-invasive, and affordable treatment that is inhaled through essential oils obtained from aromatic herbs. In peppermint inhalation therapy, the aromatic essence stimulates the olfactory receptor cells and then transmits them to the limbic system, causing a positive effect (Farahani et al., 2019; Hockenberry & Wilson, 2018). Additionally, Swedish massage is one of the common non-pharmacological nursing interventions that is considered an easy-to-apply, non-invasive, and cost-effective method to decrease the level of CINV and prevent further complications (Rajendran, 2016). It is performed by demonstrating specific techniques which include effleurage, petrissage, tapotement, friction, and vibration using facilitating oil on the skin (Miranda Ayers & Olowe., 2015).

A pediatric oncology nurse works as a dedicated member within a multidisciplinary team of health professionals for the management of children with leukemia. Therefore, pediatric oncology nurses have an integral role in the management of CINV for those children. They regularly assess, monitor, prevent, treat, and evaluate children's conditions associated with CINV (Hockenberry & Wilson, 2018). Hence, this study was conducted to help in controlling CINV, which is concomitant with higher accordance for chemotherapy treatment and fewer complications thus improving children's quality of life and their health status outcomes. Therefore, they need to integrate simple non-pharmacological nursing measures such as Swedish massage and peppermint inhalation to control the side effects of chemotherapy.