Breast cancer is the most common cancer among women worldwide [1]. In Korea, it is the second most prevalent cancer among women. The 5-year and 10-year relative survival rates are notably high, at 93.8% and 89.4% respectively, attributed to early diagnosis and advanced treatment options [1, 2]. With the rise in survival rates, patients are living longer as survivors, highlighting the need to focus on the health challenges they face [3, 4].

Cancer diagnosis induces significant psychological distress in patients [5]. Immediately following diagnosis, breast cancer patients often experience psychological problems such as anxiety, depression, worry, fear, and sadness. They may also experience physical symptoms like sleep disorders and fatigue, in addition to financial challenges [5, 6, 7]. In the initial stages post-diagnosis, breast cancer patients deal with psychological distress as they grapple with their diagnosis and confront an uncertain future with the disease [8]. Psychological distress is defined as an unpleasant emotional state that disrupts their ability to effectively respond to treatment across physical, psychological, social, and spiritual dimensions [9]. It includes a spectrum of negative emotions such as worry, anxiety, embarrassment, sadness, anger, guilt, and depression [5, 10].

The time of cancer diagnosis marks a critical juncture where patients must come to terms with their new reality and actively participate in their treatment plan [11]. Elevated levels of psychological distress can compromise decision-making abilities regarding treatment options and lead to increased unmet needs, complicating the adjustment to life as a cancer patient [12]. Specifically, high psychological distress at the time of breast cancer diagnosis adversely impacts the patients' quality of life by diminishing their satisfaction with cancer treatment and reducing their capacity to manage the sequelae or adverse effects of the treatment [13, 14, 15]. Consequently, a comprehensive examination of the factors that contribute to psychological distress in newly diagnosed breast cancer patients is essential. Identifying those at high risk and implementing interventions to reduce psychological distress are critical steps in improving patient outcomes [16].

Internationally, research efforts have consistently focused on determining the extent of psychological distress and related factors in newly diagnosed breast cancer patients, as well as developing and validating educational programs that address common psychological and social symptoms or difficulties [5, 17, 18, 19, 20, 21]. In South Korea, studies have been conducted to identify factors associated with psychological distress [22] and to validate distress management programs [3] for breast cancer patients who are currently undergoing treatment or have completed primary treatment. However, there have been few studies that specifically explore distress-related factors in newly diagnosed breast cancer patients [23]. Therefore, the purpose of this study is to explore the prevalence of psychological distress and related factors in patients with breast cancer at the time of diagnosis.

This cross-sectional study examined the prevalence of psychological distress and its associated factors in patients with breast cancer at the time of diagnosis. The average psychological distress score among participants was 5.22 points. According to the NCCN guidelines, which set a cut-off value at 4 points [9], 32.6% of participants fell into the mild distress category, while 67.4% were classified as experiencing moderate to severe distress. These findings align closely with those of Ciambella et al. [7], who reported that 66.5% of newly diagnosed breast cancer patients experienced moderate to severe stress using the same scale. However, this study's results show a higher prevalence of moderate to severe distress compared to the study of Zhao et al. [24], which found that 42.3% of patients undergoing treatment for breast cancer fell into this category, and that of Pang et al. [25], which reported that 50.8% of breast cancer survivors experienced moderate to severe distress.

Patients diagnosed with breast cancer often experience significant psychological distress due to life changes brought on by the diagnosis, anxiety about the treatment process, uncertainty about the future, and concerns regarding treatment side effects [5]. Those who suffer from severe psychological distress at the time of diagnosis tend to experience persistently high levels of distress even after survival [16]. Furthermore, psychological distress can adversely affect medical outcomes, including recovery from surgery and the experience of treatment side effects. This underscores the importance of developing practical approaches and strategies to identify psychological distress and manage high-risk patients from the outset [7, 14]. Therefore, it is essential to periodically assess the level of psychological distress from the time of cancer diagnosis and provide psychosocial support to mitigate it.

When we conducted logistic regression to identify factors influencing psychological distress in newly diagnosed breast cancer patients, we found that nervousness, fears, and financial burden were significant contributors. These factors differ from those affecting psychological distress in patients who have completed breast cancer treatment, which include age, fatigue, worry, anxiety, depression, and fear of cancer recurrence [22, 26, 27]. Following a breast cancer diagnosis, psychological distress is shaped by emotional factors such as nervousness and fear, along with financial concerns associated with accepting the diagnosis and preparing for treatment. In contrast, during or after treatment, psychological distress stems from the physical side effects of treatment, fear of cancer recurrence, and worries about resuming normal life [26, 27]. Therefore, psychological support and interventions need to be tailored to the specific needs of patients at each stage.

In this study, nervousness was identified as the strongest factor influencing psychological distress. Patients who responded "yes" to experiencing nervousness were 5.50 times more likely to be categorized within the moderate-severe distress group compared to those who answered "no." This finding aligns with research by Liu et al. [28], which also recognized nervousness as a significant factor affecting psychological distress among newly diagnosed breast cancer patients. Similarly, Ludwigson et al. [5], Mertz et al. [29], and Park et al. [16] reported that nervousness, along with worry, was the most prevalent emotional issue among patients at the time of their breast cancer diagnosis. The diagnosis of cancer is, in itself, an immensely stressful event for patients [12]. Upon diagnosis, patients are faced with the need to accept their condition and formulate treatment plans [28]. Nervousness can adversely impact a patient’s ability to manage their health or engage actively in their treatment. Therefore, it is crucial to assess and address nervousness in this group from the outset, possibly through psychological interventions designed to help patients adjust and cope, thereby mitigating negative emotional responses during treatment. Despite its significance, few studies have specifically examined nervousness in newly diagnosed breast cancer patients [28], highlighting a gap that warrants further investigation.

Next, participants who reported fears were 5.35 times more likely to fall into the moderate-severe psychological distress category compared to those who did not report such issues. Fears, along with worry and anxiety, were identified as the most significant contributors to psychological distress in a study by Ciambella et al. [7], which focused on newly diagnosed breast cancer patients. The diagnosis of cancer and subsequent treatment introduce significant changes in patients' lives [30]. Individuals newly diagnosed with cancer often harbor vague fears concerning their future treatment [31]. Fear, a distressing emotion, naturally arises following a cancer diagnosis [32]. It continues to affect psychological distress not only during treatment but also after the completion of primary treatment for breast cancer [26, 27], and it impacts patients’ adaptation to and compliance with treatment [32]. Therefore, it is crucial to assess the level of fear, information needs, and other related factors at the time of initial diagnosis and to develop management strategies that effectively support patients throughout their treatment.

Finally, participants who reported a financial burden were 4.32 times more likely to be categorized in the moderate-severe psychological distress group compared to those who reported no burden. These findings are consistent with research by Okeke et al. [17] and Liu et al. [28], which observed that breast cancer patients at diagnosis who were uninsured, unemployed, or facing financial issues experienced increased psychological distress. Patients who encounter financial difficulties prior to diagnosis or who feel burdened by the costs of treatment often suffer adverse outcomes, such as decreased compliance with treatment and delays or avoidance of necessary care [33, 34]. This financial burden continues to affect survivors, diminishing their quality of life even after treatment has ended [35]. Consequently, there is a pressing need to establish referral pathways that provide financial support to cancer patients facing economic hardships [34].

The significance of this study lies in its exploration of psychological distress and associated factors among newly diagnosed breast cancer patients, providing essential data for the development of distress management programs. However, the use of a convenience sample from a single university hospital limits the generalizability of the findings. Future research should investigate the factors related to psychological distress in newly diagnosed breast cancer patients across various regions. The NCCN psychological distress measurement scale, employed in this study, is globally recognized for its simplicity and rapid screening capabilities. However, the PL used for assessing distress factors relies on one-word answers, which constrains the precise identification of the actual problems experienced by patients [17, 22]. Subsequent research should utilize instruments that measure psychological distress with a focus on specific details, examining the relationships between psychological distress and factors such as nervousness, fears, and financial burden.

In this study, we aimed to investigate the prevalence and influencing factors of psychological distress in newly diagnosed breast cancer patients. We discovered that 67.4% of these patients experienced moderate to severe distress, primarily due to nervousness, fears, and financial burdens. Effective management of psychological distress in patients newly diagnosed with breast cancer necessitates the identification and evaluation of distress levels from the time of diagnosis. It is essential to develop psychological distress management programs that address both emotional aspects, such as nervousness and fears, and personal factors, including economic status.