As early detection and treatment improve, increasingly many breast cancer patients in Korea are being diagnosed at younger ages [1]. This often coincides with the prime child-bearing and working stages of life [2]. Substantial evidence indicates that cancer survivors are more likely to be unemployed than the general population [2], making the decision to return to work (RTW) and its management a significant concern in survivorship. RTW affects cancer survivors not only in terms of physical and mental health but also impacts their financial burden, quality of life (QoL), and more. Additionally, these impacts vary according to different healthcare systems, cultural models, and socioeconomic factors [2-4]. Research on the RTW of breast cancer survivors (BCS) in Korea is relatively new. Cultural differences specific to the RTW of Asian cancer survivors have been noted, such as the influence of Confucian values, higher levels of self-stigma, and self-consciousness about disclosing a cancer diagnosis [2]. More research is needed on the RTW experiences and challenges of non-Western populations in order to enable the development of more effective and inclusive RTW and overall breast cancer survivorship programs and resources [2-3,5].

Cancer-related fatigue (CRF) occurs in 60% to 90% of cancer survivors during treatment [6]. CRF does not resolve immediately after treatment ends and is challenging to diagnose and manage, leading many survivors to experience ongoing fatigue even after recovery [7,8]. Additionally, posttreatment CRF is often more complex due to its potential association with long-term psychological adverse events, including hormonal changes, pain, sleep disturbances, anxiety, and depression [6-7,9]. Furthermore, CRF has been found to be negatively associated with RTW during breast cancer treatment and is linked to cognitive impairments, work limitations, and work burdens [10]. Persistent CRF can significantly hinder the ability of BCS to return to and maintain employment, thereby affecting their QoL, financial stability, and social reintegration [7,11]. This ongoing fatigue underscores the need for tailored nursing approaches that provide both physical support and psychosocial interventions to manage fatigue effectively [12]. However, research on CRF among Korean BCS, particularly concerning RTW, remains insufficient. A recent study explored the fatigue-depression-anxiety symptom cluster within a Korean BCS cohort, finding that increased fatigue correlates with greater psychological distress [13]. While existing research on similar symptom clusters has demonstrated a negative impact on QoL, many studies have not simultaneously addressed critical factors such as sleep quality and work-related challenges [14]. Additionally, mental health factors and coping skills are critical concerns that should be included in both research and subsequent interventions [15,16].

Therefore, this study aimed to identify the impact of fatigue, sleep quality, physical activity, ability to adjust to cancer, depression, cognitive function, and quality of working life on the RTW of Korean BCS. It also examined the sociodemographic and clinical context influencing these factors.

The most common reasons given by our BCS participants for change in work status align with those reported in prior research—namely, marital status [29-31], time since breast cancer diagnosis [29,30], anxiety [10,30], and quality of working life [4,31-33]. The aforementioned variables were found to be significant risk factors for one another and were found to be closely related to unemployment/job anxiety in prior research [34]. Consistent with previous research on RTW in BCS [29-31], most participants in this study were young (<50 years old) and married with children. Married BCS, including those who were divorced, separated, and widowed frequently encountered greater difficulties in RTW compared to their single counterparts. Married BCS may have caregiving and household responsibilities that can make it more challenging to manage both work and daily life at home while recovering [35,36]. Married BCS may face greater emotional and psychological burdens related to their roles within the family, and their increased responsibilities can exacerbate feelings of stress about RTW, which can be compounded by the ongoing physical challenges of cancer recovery [37]. In terms of clinical characteristics, most of the BCS in this study were in the early stages of cancer survivorship. In this study, RTW was more frequent 2 years after breast cancer diagnosis and when treatments were complete or not received, reinforcing the evidence from previous research [5,38]. There are challenges in balancing work life and therapy during the acute treatment period, which includes surgery, chemotherapy, radiation therapy, and targeted therapy. Prior research indicates that a more advanced disease stage and extensive surgery can reduce RTW, especially within 3 years of diagnosis [10]. During the treatment phase, within 2 years of a breast cancer diagnosis, BCS may face obstacles in physical recovery, psychological adjustment, and fatigue, all of which can restrict their RTW [37,38]. Thus, to facilitate RTW for BCS, it is essential to provide comprehensive support and counseling to address the physical-psychological challenges with fatigue associated with caregiving or household responsibilities [37].

Regarding mental adjustment to cancer, this study identified high scores of helplessness-hopelessness, anxious preoccupation, and fatalism. Previous research has highlighted the importance of finding individual coping mechanisms [2,15], and the findings from this study can help us better understand the mindset of Korean BCS to tailor more effective RTW interventions. In particular, traditional health beliefs such as fatalism about cancer diagnosis are deeply entrenched among women in many Asian countries, leading to negative mental health outcomes and feelings of helplessness [16]. A high prevalence of depression among Korean BCS has been reported [32], and negative psychosocial factors such as anxiety, anxious preoccupation, fatalism, and depression are associated with fatigue, which can hinder RTW [3,39,40]. This study found that BCS who returned to work had lower levels of anxious preoccupation compared to those who did not. The findings support previous research indicating that BCS who did not return to work experience higher levels of depression, anxiety, and distress [16]. Therefore, returning to work may be associated with improved mental health factors for cancer survivors. To establish causality, however, further research is needed to explore a broader range of psychological factors and intervention strategies.

Quality of work life in our study was lower than that reported in a previous study of BCS in Europe [41]. The moderate quality of working life observed among our participants, along with a lower RTW rate, suggests significant room for improvement in RTW conditions in Korea. In our research, quality of working life emerged as a significant predictor of RTW. BCS who reported a higher quality of working life were more likely to successfully return to and sustain their employment. Consistent with earlier research, our findings highlight the critical role of accessible physical, social, emotional, and informational support [42-44].

Our finding of medium levels of fatigue is consistent with previous research in Western BCS populations [3,9]. Previous Korean research has found fatigue and fitness to be the most frequent physical difficulties impeding RTW among BCS [10]. In comparison to a recent study on BCS with moderate or greater fatigue [34], this study also found low levels of total physical activity. This is particularly noteworthy considering that more than half of the participants were within 2 years of their diagnosis, and physical activity for CRF management and planning for RTW can be helpful after active treatment is completed. Indeed, the variable that showed the most prominent between-group difference in RTW was fatigue. This study showed that both subjective fatigue and physical fatigability were associated with RTW, confirming the findings of previous studies that demonstrated associations between CRF and RTW [2,10,31]. Additionally, given the established positive correlation between exercise and RTW, we recommend providing educational support for regular exercise management and fatigue monitoring at all stages of survivorship to facilitate RTW for BCS [10].

Furthermore, sleep is an important factor for cancer survivors, as sleep disturbances have been found to significantly increase healthcare expenditures and absenteeism in the United States [45]. Previous studies have indicated that insomnia is twice as prevalent among BCS, with concurrent and heightened symptoms of sleep disturbance linked to greater cancer-related uncertainty and fatigue, particularly in younger BCS (<50 years) [9]. As our study population also exhibited borderline poor sleep quality, efforts to emphasize the importance of sleep are critical in interventions and support programs for Korean BCS [2].

In order to increase RTW, some Western countries provide a wide range of detailed information through online sources [46]. Improving the availability of RTW information online and in the workplace for Korean BCS may help normalize RTW and provide opportunities for colleagues, supervisors, and employers to understand and support their colleagues who are cancer survivors [42]. We advocate for a dual emphasis on both physical and psychosocial rehabilitation—including physical therapy, exercise programs for fatigue management, psychoeducation, and sleep support—in RTW programs, alongside vocational resources such as occupational counseling and the involvement of vocational experts in creating tailored RTW plans [2,46]. In Korea, the development and implementation of such multidisciplinary interventions will necessitate comprehensive coordination among oncologists, clinical psychologists, social workers, occupational experts, and workplace managers and employers [46]. As nurses are at the frontline of treatment for BCS, they are well-positioned to assess issues like fatigue, sleep disturbances, and anxiety, and to utilize study findings to educate and support RTW, particularly in roles as liaisons and resource providers.

The strengths of this study included the analysis of understudied RTW parameters and its focus on an understudied population of BCS regarding RTW. A limitation of this study was the inability to infer causality due to the cross-sectional design. More longitudinal and intervention-based studies are needed to examine RTW in Korean BCS. Additionally, the small sample size of this study may limit the generalizability of its findings. Future studies on RTW would benefit from a more detailed focus on specific types of employment, including professional and managerial roles, positions requiring significant physical effort, self-employment, and jobs that involve night shifts or temporary work.

In conclusion, this study of Korean BCS found both subjective fatigue and physical fatigability to be strongly negatively associated with RTW, while high-quality sleep appeared to have a positive association. Anxious preoccupation also showed a significant relationship with RTW, highlighting the importance of including a variety of psychological factors in future RTW analyses. Previous studies in Korea have primarily focused on the clinical aspects of recovery and the prevention of cancer recurrence. However, there is a growing need to shift attention towards cancer survivorship. Future initiatives should aim to enhance physical and psychosocial support resources and develop RTW interventions tailored to Korean BCS. These interventions should focus on alleviating CRF, reducing anxious preoccupation, and improving the quality of working life.