In 2018, the global incidence of cancer is estimated to have risen to 18.1 million new cases, resulting in 9.6 million deaths. The total number of individuals diagnosed with cancer worldwide is estimated at 43.8 million, as reported by the (W.H.O., 2018). In Indonesia, data from the Riskesdas survey spanning 2013 to 2018 reveals an increase in the prevalence of cancer patients from 1.4% to 1.49% (Pangribowo, 2019)

Receiving a cancer diagnosis constitutes a significant life stressor with profound effects on an individual's physiological, psychological, and physical well-being. The trajectory of cancer may involve challenges such as pain, weakness, sleep disruptions, and fatigue, ultimately resulting in limitations in daily functioning. Individuals with cancer often contend with symptoms associated with both their treatment and the specific type and stage of their disease. Among these symptoms, sleep disturbance emerges as a prevalent and distressing issue, significantly impacting the overall quality of life (Wu & Harden, 2015). Insomnia, in particular, is a common sleep disorder experienced by many patients diagnosed with cancer. This disruption in sleep patterns is frequently observed from the initial diagnosis and can persist throughout the patient's life (Al Maqbali, 2020).

Evidence suggests that sleep disturbances among cancer patients can detrimentally impact the quality of life, covering both the physical and mental aspects of well-being. These sleep disruptions have been associated with potential cancer recurrence, hindered healing processes, diminished cognitive function, and decreased work activity. Recognizing the importance of self-care in managing chronic diseases, individuals adopt it as a crucial behavior to preserve health, control diseases, and minimize associated complications (Wong et al., 2018) Practicing self-care effectively can greatly relieve symptoms and complications, decrease hospitalizations, and improve both the quality of life and the sense of control over chronic diseases. (Butler et al., 2019) conducted research categorizing self- care into six domains based on Abraham Maslow's (1943) framework: (1) Physical Domain, (2) Professional Domain, (3) Relational Domain, (4) Emotional Domain, (5) Psychological Domain, and (6) Spiritual Domain.

Several evidence bases related to self-care to treat sleep disorders or improve sleep quality have been applied. A study by Ghavami on post-artery bypass patients showed that self-care interventions could improve the patient's sleep quality (p=0.001). In addition, other self-care interventions, such as physical activity such as walking every day, can improve sleep disturbances, sleep quality, and sleep duration (Wu & Harden, 2015). Other interventions, such as mindfulness meditation, can improve sleep quality in adults with sleep disorders (Butler et al., 2019). Progressive muscle relaxation can improve adolescents' sleep quality. This article was written for several reasons. First, to find out how the effects of some appropriate and valid self-care in overcoming sleep disorders, especially in cancer patients. Additionally, the findings may be robust evidence supporting the implementation of standardized sleep-promoting policies and procedures in cancer care settings.

In this literature review, the author uses Preferred Reporting Items for Literature Review and Meta-Analysis (PRISMA) as a reference in collecting related articles. In addition, this systematic review is carried out by adjusting to the PICO model that has been created. This search retrieved data from 2017 to 2022 using ProQuest, Clinical Key Nursing, and Scopus databases. Search terms use free text words just as search terms use both free text words. and the title of the medical subject, that is, the term MeSH, to search for papers in reviews, i.e.,("Sleep") OR (" Insomnia") OR ("sleep disturbances") OR ("sleep disorder") or ("self-care") or ("exercise") or ("yoga") or ("self-care intervention") Furthermore, a compilation of references is curated from the examination of studies and review articles to identify additional relevant research.

A filtration process was applied following a database search that yielded 620 results. Inclusion criteria for this study encompassed: 1) articles employing a research design of Randomized Controlled Trials (RCT) and 2) those involving experimental research. Exclusion criteria involved 1) articles published more than five years ago or before 2017 and 2) articles categorized as literature reviews, systematic reviews, or meta-analyses. Of these, 405 papers were excluded based on criteria such as exceeding the five-year timeframe, not being a research article, or lacking full-text availability. Consequently, 8 studies met the eligibility criteria and were identified for inclusion in the literature review; see Figure 1 for a detailed process.

A total of 8 articles have been reviewed. Some of the findings in the reviewed article show several self- care interventions to manage pain, such as mindfulness, exercise, yoga, and dance. and the effects of personal psychotherapy. All self-care interventions administered were performed on adult patients with cancer. As a large result, research shows that self-care interventions provided are significantly able to help reduce sleep disorders and other symptoms caused by cancer. The review results are described in the synthesis Table 1 and Table 2:

Of the eight articles discussed by the authors related to the effect of giving self-care interventions related to sleep disturbances in cancer patients, most of them showed a decrease in sleep disturbances in cancer patients. Still, there was one article that did not show significant results related to sleep disturbances. Of all the articles found, all were forms of intervention from self-care. There are three articles related to insomnia, one related to sleep quality, and four others related to sleep disturbance.

Numerous previous studies have highlighted the frequent occurrence of sleep disturbances among cancer patients. These disturbances encompass a broad spectrum, ranging from the disease's physical impact to the effects of various treatments, including surgery, chemotherapy, radiotherapy, and medications. Additionally, psychosocial stressors such as anxiety, depression, and concerns related to family or financial situations also contribute to sleep disturbances in cancer patients (Al Maqbali, 2020); (Strik et al., 2021)Pinpointing the exact etiology of sleep disorders in this context proves challenging. However, certain demographic factors, including being female, older age, lower levels of education, and reduced physical activity, have been consistently associated with an increased likelihood of experiencing sleep disorders (Al Maqbali, 2020)

Certain studies indicate that exercise can affect various physiological functions during sleep, including body temperature regulation, heart function, endocrine activity, metabolism, and immune function (Chennaoui et al., 2015). Additionally, the quality of life of individuals significantly impacts the prevalence of sleep disorders, as demonstrated in a study conducted by (Lee et al., 2011). Individuals reporting sleep disorders often exhibit a considerably poorer quality of life.

Poor sleep quality has been associated with unfavorable emotional consequences, linking unhealthy coping to poor sleep and healthy coping to good sleep quality. Neurobiological level, sleep deprivation, and subpar sleep quality can result in Connectivity within the medial prefrontal cortex and ventral anterior cingulate. This indicates possible challenges in overseeing and restraining emotional regulation (Talley & Shelley-Tremblay, 2020) . Self-care interventions, which universally aim to induce a relaxed state in individuals, play a crucial role. Creating a relaxed bodily state enhances attention, providing control over the autonomic nervous system, ultimately reducing the impact of worries and promoting a calm mood, thereby alleviating mood disorders. An efficient and secure approach model, such as self-care, strives to enhance sleep comfort, overall comfort levels, and the quality of life for the individuals involved. Traditionally, physicians often prescribe drugs to address poor sleep issues, but these medications may carry specific side effects such as memory impairment, resistance, dependency, and the risk of addiction.

These results suggest that self-care interventions are highly effective in mitigating sleep disorders for cancer patients. From this, it can be concluded that sleep disorders can be influenced by physical and psychological conditions, so the a need to manage both physical and emotional problems of cancer patients.

Based on several journals that have been reviewed, it can be concluded that self-care is very beneficial in reducing sleep disorders in cancer patients. Some of these self-care interventions can be used to support interventions or holistic interventions for cancer patients in overcoming disorders due to the course of the disease and treatment, such as sleep disorders.