Prevalence and Correlates of Suicidal Ideation among Psycho-Oncology Outpatients
As a leading cause of death worldwide, cancer claimed about 9.6 million lives in 2018. Among the various psychiatric symptoms experienced by cancer patients, a grave condition that necessitates immediate intervention is the presence of suicidal ideation. Considering its high prevalence among cancer patients compared to the general population and the possibility of its progression to death by suicide, health professionals caring for cancer patients should be able to detect suicidal ideation in a timely manner and provide appropriate interventions. Untreated psychiatric disorders result in adverse consequences on cancer treatment. Therefore, in response to the increasing number of cancer patients, the field of psycho-oncology, addressing psychological, social, and spiritual aspects of cancer, emerged and now occupies an essential position in the integrated care of cancer patients experiencing various psychiatric issues, including suicidal ideation. Until now, most studies on the prevalence and risk factors of suicidal ideation among those diagnosed with cancer were performed on cancer patients with active disease in cancer treatment units. They are a unique group to which the knowledge of the common risk factors of suicidal ideation would not be easily applicable. Likewise, patients in a psycho-oncology outpatient clinic may have their own characteristics regarding suicidal ideation. To our knowledge, few studies addressed the risk factors of suicidal ideation among general psycho-oncology outpatients; however, they either evaluated only limited aspects of clinical factors (depression and hopelessness) or included patients with major depressive disorder. Importantly, the results from our study would be clinically helpful for psycho-oncologists when screening for suicidal ideators. The anticipated increase of cancer patients led to an increased emphasis on their health-related quality of life (HRQOL). The HRQOL is a multidimensional concept that encompasses physical, social, emotional, and cognitive functioning. Patients with cancer usually experience a lowered quality of life, which was reported to increase the risk of suicidal ideation in chronic non-cancer patients. Therefore, as potential correlates of suicidal ideation among cancer patients, it appears to be essential to address their HRQOL and common psychopathologies, such as depression and anxiety. The current study determined the prevalence of suicidal ideation and identified the contributing factors among patients in a psycho-oncology outpatient clinic. We hypothesized that poor HRQOL in certain dimensions would increase the risk of suicidal ideation, besides other psychiatric symptoms.   Participants and procedure This study was performed in a psycho-oncology clinic in the Asan Medical Center, Seoul, Korea, a tertiary hospital providing all fields of specialties throughout the country. Patients aged 18 years or above with psychiatric problems previously diagnosed with cancer are treated at the clinic irrespective of their current cancer treatment status. A routine symptom survey is used as part of clinical practice. A consecutive series of medical records of the first visits to the clinic by those diagnosed clinically according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, during the study period (from May 21, 2019 to May 20, 2020) were reviewed by the authors (CHKP, HK, and YK). The exclusion criteria were patients who refused to answer the survey, were medically markedly unstable, were aged 80 years or above, or had difficulty understanding the Korean language. The Asan Medical Center Institutional Review Board approved this study (2020-0898). Since this was a retrospective chart review, informed consent was waived. Measures Demographic and cancer-related factors Demographic factors included sex and age. The European Network of Cancer Registries was used to determine the date of cancer diagnoses. The 5th edition of the World Health Organization Classification of Tumors categorized the cancer types. In the case of multiple primary cancers, the type that dominated the recent treatment was chosen for the analysis. Disease status and cancer treatment status were decided based on the definition developed for an earlier study and modified by the authors. Disease status was categorized into disease-free or active disease. We added radiofrequency ablation as an alternative modality to surgery for one of the original disease-free conditions: “metastatic cancer that had been surgically removed, and no documentation of recurrence.” Cancer treatment status was grouped into no cancer treatment or cancer treatment (surgery, chemotherapy, radiotherapy, or other therapy—hormone therapy, immunotherapy, and targeted therapy) given during the 2 months before the assessment date. This duration was adopted from the aforementioned study. Brain malignancy refers to brain cancer, brain metastasis of primary cancer, and brain involvement by hematolymphoid tumors. Suicidal ideation The presence or absence of suicidal ideation was determined using Item 9 of the Patient Health Questionnaire-9 (PHQ-9). Evidence endorsing its use as a general screening tool for identifying suicidal ideators continues to accumulate. Item 9 is scored based on the symptom frequency. For the current study, the patients who experienced suicidal ideation at least several days during the past 2 weeks were designated as suicidal ideators and others as control patients, following the convention of previous studies to ensure comparability. Functional and emotional status The functional status was assessed using the Functional Assessment of the Cancer Therapy–General (FACT-G), a 27-item self-report questionnaire evaluating multiple aspects of the HRQOL during the past week. It has four subscales: “physical well-being,” “social/family well-being,” “emotional well-being,” and “functional well-being.” A higher score indicates a higher HRQOL. The emotional status was evaluated using the Hospital Anxiety and Depression Scale (HADS) for depressive and anxiety symptoms and the distress thermometer (DT) for psychological distress. The HADS is a 14-item self-report scale consisting of two subscales with seven items, each measuring the severity of depressive and anxiety symptoms during the past week in a universal medical setting. A higher score means a higher level of depressive and anxiety symptoms. The DT is a 1-item self-report scale measuring psychological distress during the past week in cancer patients, ranging from 0 (no distress) to 10 (extreme distress). Statistical analysis The patients who responded to the PHQ-9 Item 9 and those who did not or were excluded from the survey were defined as “responders” and “non-responders,” respectively. The characteristics between the former and the latter were compared to assess the representativeness of our study sample using two-sample t-tests for continuous variables and chi-squared tests for categorical variables. The 2-week prevalence of suicidal ideation among the responders was obtained. Then, among the responders, each demographic, cancer-related and psychiatric-related factors, and functional and emotional status was compared between non-suicidal controls and suicidal ideators using the aforementioned tests. Logistic regression was performed to investigate the relationship between suicidal ideation and demographic, cancer-related and psychiatric-related factors, and functional and emotional status. First, univariable logistic regression was conducted using the presence or absence of suicidal ideation as the outcome values and each potential explanatory variable. Based on the results of the univariable logistic regression and considering the multicollinearity among the potential explanatory variables and clinical knowledge, we built a multivariable logistic regression model after adjusting for sex and age. We performed multiple imputation with 10 datasets for all the variables except for the outcome variable to handle the missing data. The results of the analysis on 10 completed datasets were combined using Rubin’s rule. Descriptive analyses were conducted using SPSS for Windows version 21.0 for PC (IBM Corp., Armonk, NY, USA), and multiple imputation and logistic regression were performed with R Statistical Software version 3.6.1 (R Foundation for Statistical Computing, Vienna, Austria). For multiple comparisons in and , the Bonferroni correction was employed to determine the p value cut-offs for statistical significance. For , a two-tailed p value less than 0.050 was accepted as statistically significant.   This study was performed in a psycho-oncology clinic in the Asan Medical Center, Seoul, Korea, a tertiary hospital providing all fields of specialties throughout the country. Patients aged 18 years or above with psychiatric problems previously diagnosed with cancer are treated at the clinic irrespective of their current cancer treatment status. A routine symptom survey is used as part of clinical practice. A consecutive series of medical records of the first visits to the clinic by those diagnosed clinically according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, during the study period (from May 21, 2019 to May 20, 2020) were reviewed by the authors (CHKP, HK, and YK). The exclusion criteria were patients who refused to answer the survey, were medically markedly unstable, were aged 80 years or above, or had difficulty understanding the Korean language. The Asan Medical Center Institutional Review Board approved this study (2020-0898). Since this was a retrospective chart review, informed consent was waived.   Demographic and cancer-related factors Demographic factors included sex and age. The European Network of Cancer Registries was used to determine the date of cancer diagnoses. The 5th edition of the World Health Organization Classification of Tumors categorized the cancer types. In the case of multiple primary cancers, the type that dominated the recent treatment was chosen for the analysis. Disease status and cancer treatment status were decided based on the definition developed for an earlier study and modified by the authors. Disease status was categorized into disease-free or active disease. We added radiofrequency ablation as an alternative modality to surgery for one of the original disease-free conditions: “metastatic cancer that had been surgically removed, and no documentation of recurrence.” Cancer treatment status was grouped into no cancer treatment or cancer treatment (surgery, chemotherapy, radiotherapy, or other therapy—hormone therapy, immunotherapy, and targeted therapy) given during the 2 months before the assessment date. This duration was adopted from the aforementioned study. Brain malignancy refers to brain cancer, brain metastasis of primary cancer, and brain involvement by hematolymphoid tumors. Suicidal ideation The presence or absence of suicidal ideation was determined using Item 9 of the Patient Health Questionnaire-9 (PHQ-9). Evidence endorsing its use as a general screening tool for identifying suicidal ideators continues to accumulate. Item 9 is scored based on the symptom frequency. For the current study, the patients who experienced suicidal ideation at least several days during the past 2 weeks were designated as suicidal ideators and others as control patients, following the convention of previous studies to ensure comparability. Functional and emotional status The functional status was assessed using the Functional Assessment of the Cancer Therapy–General (FACT-G), a 27-item self-report questionnaire evaluating multiple aspects of the HRQOL during the past week. It has four subscales: “physical well-being,” “social/family well-being,” “emotional well-being,” and “functional well-being.” A higher score indicates a higher HRQOL. The emotional status was evaluated using the Hospital Anxiety and Depression Scale (HADS) for depressive and anxiety symptoms and the distress thermometer (DT) for psychological distress. The HADS is a 14-item self-report scale consisting of two subscales with seven items, each measuring the severity of depressive and anxiety symptoms during the past week in a universal medical setting. A higher score means a higher level of depressive and anxiety symptoms. The DT is a 1-item self-report scale measuring psychological distress during the past week in cancer patients, ranging from 0 (no distress) to 10 (extreme distress).   Demographic factors included sex and age. The European Network of Cancer Registries was used to determine the date of cancer diagnoses. The 5th edition of the World Health Organization Classification of Tumors categorized the cancer types. In the case of multiple primary cancers, the type that dominated the recent treatment was chosen for the analysis. Disease status and cancer treatment status were decided based on the definition developed for an earlier study and modified by the authors. Disease status was categorized into disease-free or active disease. We added radiofrequency ablation as an alternative modality to surgery for one of the original disease-free conditions: “metastatic cancer that had been surgically removed, and no documentation of recurrence.” Cancer treatment status was grouped into no cancer treatment or cancer treatment (surgery, chemotherapy, radiotherapy, or other therapy—hormone therapy, immunotherapy, and targeted therapy) given during the 2 months before the assessment date. This duration was adopted from the aforementioned study. Brain malignancy refers to brain cancer, brain metastasis of primary cancer, and brain involvement by hematolymphoid tumors.   The presence or absence of suicidal ideation was determined using Item 9 of the Patient Health Questionnaire-9 (PHQ-9). Evidence endorsing its use as a general screening tool for identifying suicidal ideators continues to accumulate. Item 9 is scored based on the symptom frequency. For the current study, the patients who experienced suicidal ideation at least several days during the past 2 weeks were designated as suicidal ideators and others as control patients, following the convention of previous studies to ensure comparability.   The functional status was assessed using the Functional Assessment of the Cancer Therapy–General (FACT-G), a 27-item self-report questionnaire evaluating multiple aspects of the HRQOL during the past week. It has four subscales: “physical well-being,” “social/family well-being,” “emotional well-being,” and “functional well-being.” A higher score indicates a higher HRQOL. The emotional status was evaluated using the Hospital Anxiety and Depression Scale (HADS) for depressive and anxiety symptoms and the distress thermometer (DT) for psychological distress. The HADS is a 14-item self-report scale consisting of two subscales with seven items, each measuring the severity of depressive and anxiety symptoms during the past week in a universal medical setting. A higher score means a higher level of depressive and anxiety symptoms. The DT is a 1-item self-report scale measuring psychological distress during the past week in cancer patients, ranging from 0 (no distress) to 10 (extreme distress).   The patients who responded to the PHQ-9 Item 9 and those who did not or were excluded from the survey were defined as “responders” and “non-responders,” respectively. The characteristics between the former and the latter were compared to assess the representativeness of our study sample using two-sample t-tests for continuous variables and chi-squared tests for categorical variables. The 2-week prevalence of suicidal ideation among the responders was obtained. Then, among the responders, each demographic, cancer-related and psychiatric-related factors, and functional and emotional status was compared between non-suicidal controls and suicidal ideators using the aforementioned tests. Logistic regression was performed to investigate the relationship between suicidal ideation and demographic, cancer-related and psychiatric-related factors, and functional and emotional status. First, univariable logistic regression was conducted using the presence or absence of suicidal ideation as the outcome values and each potential explanatory variable. Based on the results of the univariable logistic regression and considering the multicollinearity among the potential explanatory variables and clinical knowledge, we built a multivariable logistic regression model after adjusting for sex and age. We performed multiple imputation with 10 datasets for all the variables except for the outcome variable to handle the missing data. The results of the analysis on 10 completed datasets were combined using Rubin’s rule. Descriptive analyses were conducted using SPSS for Windows version 21.0 for PC (IBM Corp., Armonk, NY, USA), and multiple imputation and logistic regression were performed with R Statistical Software version 3.6.1 (R Foundation for Statistical Computing, Vienna, Austria). For multiple comparisons in and , the Bonferroni correction was employed to determine the p value cut-offs for statistical significance. For , a two-tailed p value less than 0.050 was accepted as statistically significant.   Baseline characteristics of the sample In total, 740 patients visited the psycho-oncology clinic during the study period, of whom 545 (73.7%) responded. presents the demographic and cancer-related characteristics of the non-responders (n=195) and responders (n=545). Significant differences between the groups were observed reflecting the difficulty in screening male patients, older patients, patients diagnosed with malignancy other than breast cancer, patients who had not received any anticancer therapy during the recent 2 months, and patients with a depressive disorder or delirium with the Bonferroni-corrected p value threshold of 0.0038 (0.050/13). Prevalence of suicidal ideation Among the patients, 252 (46.2%) reported suicidal ideation, among whom 178 (70.63%), 35 (13.88%), and 39 (15.48%) patients checked “several days,” “more than half the days,” and “nearly every day,” respectively. Comparisons between non-suicidal controls and suicidal ideators With the Bonferroni-corrected p value threshold of 0.0025 (0.050/20), patients were more likely to be suicidal ideators if they had an active disease ( p <0.001) or had a depressive disorder ( p <0.001) . Regarding the functional status, non-suicidal controls showed significantly higher levels in each and every dimension of the HRQOL, including physical ( p <0.001), emotional ( p <0.001), and functional ( p <0.001) well-being. Concerning the emotional status, suicidal ideators were more likely to have a higher severity of depressive symptoms ( p < 0.001), anxiety symptoms ( p <0.001), and psychological distress ( p <0.001). In an additional analysis on all three groups using analysis of variance—non-responders, non-suicidal controls, and suicidal ideators—there were significant differences in sex ( p =0.001), age ( p <0.001), index cancer site ( p =0.002), disease status ( p <0.001), any anticancer therapy ( p <0.001), psychiatric diagnosis ( p <0.001), all the HRQOL dimensions except for social/family well-being ( p <0.001 for each), and emotional status ( p <0.001 for each) using a Bonferroni-adjusted significant threshold of 0.0025 (0.050/20) ( , only online). Correlates of suicidal ideation presents the results of univariable and multivariable logistic regression. Social/family well-being, functional well-being, and HADS anxiety was removed from the final model due to multicollinearity issues with emotional well-being, physical well-being, and HADS depression, respectively. After adjusting for sex and age, active disease status ( p =0.031), lower levels of physical ( p =0.038) and emotional well-being ( p =0.011), and higher degrees of depressive symptoms ( p =0.001), and psychological distress ( p =0.001) were found to be significantly associated with the presence of suicidal ideation.   In total, 740 patients visited the psycho-oncology clinic during the study period, of whom 545 (73.7%) responded. presents the demographic and cancer-related characteristics of the non-responders (n=195) and responders (n=545). Significant differences between the groups were observed reflecting the difficulty in screening male patients, older patients, patients diagnosed with malignancy other than breast cancer, patients who had not received any anticancer therapy during the recent 2 months, and patients with a depressive disorder or delirium with the Bonferroni-corrected p value threshold of 0.0038 (0.050/13).   Among the patients, 252 (46.2%) reported suicidal ideation, among whom 178 (70.63%), 35 (13.88%), and 39 (15.48%) patients checked “several days,” “more than half the days,” and “nearly every day,” respectively.   With the Bonferroni-corrected p value threshold of 0.0025 (0.050/20), patients were more likely to be suicidal ideators if they had an active disease ( p <0.001) or had a depressive disorder ( p <0.001) . Regarding the functional status, non-suicidal controls showed significantly higher levels in each and every dimension of the HRQOL, including physical ( p <0.001), emotional ( p <0.001), and functional ( p <0.001) well-being. Concerning the emotional status, suicidal ideators were more likely to have a higher severity of depressive symptoms ( p < 0.001), anxiety symptoms ( p <0.001), and psychological distress ( p <0.001). In an additional analysis on all three groups using analysis of variance—non-responders, non-suicidal controls, and suicidal ideators—there were significant differences in sex ( p =0.001), age ( p <0.001), index cancer site ( p =0.002), disease status ( p <0.001), any anticancer therapy ( p <0.001), psychiatric diagnosis ( p <0.001), all the HRQOL dimensions except for social/family well-being ( p <0.001 for each), and emotional status ( p <0.001 for each) using a Bonferroni-adjusted significant threshold of 0.0025 (0.050/20) ( , only online).   presents the results of univariable and multivariable logistic regression. Social/family well-being, functional well-being, and HADS anxiety was removed from the final model due to multicollinearity issues with emotional well-being, physical well-being, and HADS depression, respectively. After adjusting for sex and age, active disease status ( p =0.031), lower levels of physical ( p =0.038) and emotional well-being ( p =0.011), and higher degrees of depressive symptoms ( p =0.001), and psychological distress ( p =0.001) were found to be significantly associated with the presence of suicidal ideation.   The present study determined the prevalence and correlates of suicidal ideation among patients visiting a psycho-oncology clinic. Approximately half of the patients reported suicidal ideation during the previous 2 weeks. Active disease status, physical and emotional well-being in the functional status, and depressive symptoms and psychological distress in the emotional status were independent contributors to suicidal ideation. The prevalence of suicidal ideation in our study (46.2%) was considerably higher than that among the patients in cancer treatment units. Our finding was similar to that of an earlier work on cancer patients with major depression referred to a psychiatry service, 51.4%. The high percentages in the previous study and the present study could be due to the high similarity of the study samples in terms that, like the previous study, the majority (71.9%) of our sample had also been referred to the psycho-oncology clinic and almost all (98.0%) had been diagnosed with a psychiatric disorder (data not shown). The current result was consistent with that of a previous study reporting that suicidal ideation is more prevalent in psychiatric patients than in the general population. The prevalence in our study sample was substantially higher than that of the general population, ranging from 1.1% to 19.8%. Particularly, considering a large-scale study using the PHQ-9 Item 9 that reported a 2.6% prevalence of suicidal ideation, our result suggests that the patients in a psycho-oncology clinic had over 17 times the risk of suicidal ideation than the general population. Suicide is not a momentary event, rather an endpoint of a course called the suicidal process. To prevent catastrophic consequences, such as suicide attempt and death by suicide, individuals at high risk must be identified as early as possible, namely at the stage of suicidal ideation, and should be provided with timely interventions. The high prevalence of suicidal ideation among patients in a psycho-oncology clinic indicates the importance of identifying and understanding the correlates of suicidal ideation specific to this group. Psycho-oncology outpatients are a heterogeneous group comprising individuals who have active disease, whether undergoing treatment or not, and disease-free individuals, whether receiving follow-up care or not. Among these, only patients with active disease are considered cancer patients. The risk of recent suicidal ideation among cancer patients compared with disease-free cancer survivors has not been addressed. This study is the first to report that irrespective of the treatment status, HRQOL, and psychopathology, having active disease increases the risk of suicidal ideation independently among those with a history of a cancer diagnosis. Successful treatment of cancer could reduce suicidal ideation. Among HRQOL aspects, only lower physical and emotional well-being were risk factors for suicidal ideation among our study sample. First, physical well-being addresses somatic pain or discomfort and limitations in physical activity. The current finding was in close agreement with those of previous studies on head and neck cancer patients and advanced cancer patients. From this result, reducing physical distress originating from cancer pain or side effects of cancer treatment could effectively reduce suicidal ideation. Chronic pain, often underreported, underdiagnosed, and undertreated, is a common complication caused by residual tissue damage from cancer and its treatment. Among three types of chronic pain, including somatic, visceral, and neuropathic, neuropathic pain is usually more responsive to a combination of opioids and anti-neuropathic drugs, such as antidepressants or anticonvulsants. Psychiatrists, generally experienced in psychotropics and psychosocial interventions, could contribute to the management of chronic pain and cancer-related symptoms. Next, emotional well-being addresses hopelessness, anxiety, and sadness. Hopelessness and anxiety are risk factors of suicidal ideation among cancer patients. Concurrently, they are associated with an increased risk of depression, and sadness is a core symptom of depression. Therefore, although this dimension of the HRQOL appears to encompass a broad range of emotional responses to illness, it might partly reflect a degree of depression. In fact, a previous study showed that emotional well-being score has high sensitivity and specificity for major depression in cancer patients, and depression itself is a well-known risk factor of suicidal ideation among cancer patients. Based on the current finding, improving emotional well-being could aid in reducing suicidal ideation. Various psychosocial approaches with the potential to increase the well-being of cancer patients have been examined. Physical exercise-based interventions have short- (less than 3–8 months) and long-term effects, while cognitive behavioral therapy and mindfulness-based stress reduction show particularly short-term benefits for overall well-being. Some studies specifically addressed the improvement of dimensions of our concern—physical and emotional well-being. For example, a study on prostate cancer patients receiving radiotherapy showed that aerobic exercise is particularly effective in improving physical well-being. Cognitive behavioral therapy focusing on strengthening the coping strategies to manage stress promoted emotional well-being for breast cancer patients. Moreover, routine assessment of HRQOL is another promising strategy to improve well-being. A prospective study showed that emotional well-being and overall well-being, measured using the FACT-G, are better among cancer patients who conduct routine self-report measurements of the HRQOL and receive feedback during consultations. The authors of the study concluded that the routine use of the evaluation materials impacts doctor-patient communication. The participation of a psychiatrist as a multidisciplinary team member, evaluating and discussing the HRQOL issues, may be a potentially efficient way to not only improve well-being but also reduce suicidal ideation by extension. Depressive symptoms among cancer patients may emerge from the process of adapting to the disease along the cancer trajectory or by cancer itself, including cancer-related symptoms and treatment. The prevalence of depression among cancer patients was 8% to 24%, differing by the type of assessment tool, type of cancer, and treatment stage. We showed that greater severity of depressive symptoms was associated with the presence of suicidal ideation among psycho-oncology outpatients. Several studies have confirmed the positive association between depression and suicidal ideation among patients with various types of cancer from various settings. Psychological distress is defined as “a multifactorial unpleasant experience of a psychological (i.e., cognitive, behavioral, emotional), social, spiritual, and/or physical nature that may interfere with one’s ability to cope effectively with cancer, its physical symptoms, and its treatment.” Distress commonly occurs across the cancer trajectory, beginning at diagnosis and treatment and occurring in the post-treatment stage, and over the long term. Distress encompasses not only common psychological problems related to depression or anxiety but also other impairing conditions, such as panic attacks, social isolation, and existential and spiritual crises. We found psychological distress to be a significant contributor to the presence of suicidal ideation. This result corresponds with that of an earlier study reporting that psychological distress is a risk factor for suicidal ideation among cancer patients. Psychological distress contributes to suicidal ideation via direct and indirect pathways; for the latter, depression and demoralization mediate the relationship. Thus, the identification and treatment of both depressive symptoms and psychological distress would not only improve emotional status but also decrease the risk of suicidal ideation. Our findings regarding emotional status indicate that particularly managing depression among psychological difficulties is essential to reduce suicidal ideation as it simultaneously relates to psychological distress. Both pharmacotherapy and psychotherapy are used widely for treating depression in cancer patients. A recent meta-analysis showed that the prevalence of antidepressant prescription for cancer patients is 15.6%, somewhat higher than that of the general population in the United States. Concerning psychosocial approaches, cognitive behavioral therapy has been shown to be effective in reducing depressive symptoms among cancer patients. This study has several limitations. First, due to the cross-sectional study design, the possibility of reverse causality cannot be excluded. Second, as the PHQ-9 Item 9 does not address multifaceted aspects of suicidal ideation except for its frequency, the details such as a suicide plan could not be included in the analysis. Third, information on a history of suicide attempts was not available. Fourth, the PHQ-9 Item 9 and DT would be more suitable for screening than identifying true suicidal ideation and emotional status, respectively. Thus, we also used the HADS for an in-depth evaluation of emotional status. Fifth, as approximately half of the sample had breast cancer, the present findings may considerably reflect the characteristics of patients with breast cancer. However, given that the main purpose of this study was to examine the overall characteristics related to suicidal ideation of general psycho-oncology patients, differences seem inevitable regarding the prevalence of each cancer type within the study sample. Sixth, the study sample exclusively consisted of patients from a tertiary hospital, which suggests that generalizing the findings should be approached with caution. Despite the limitations, the strength of our study lies in the analysis of a consecutive series of medical records, providing results that reflect real-world clinical practice settings. In conclusion, this cross-sectional study revealed that approximately half of the patients in a psycho-oncology clinic experienced suicidal ideation in the previous 2 weeks. For psycho-oncology outpatients who are under active cancer treatment, show poorer physical and emotional well-being, and report more severe depressive symptoms and psychological distress, a thorough evaluation of suicidal ideation needs to be performed. Future studies with a longitudinal design should determine whether intervention on the identified risk factors can reduce suicidal ideation.   