Clinical and epidemiological factors associated with suicide in colorectal cancer

Suicide after colorectal cancer-a national population-based study

AIM

A cancer diagnosis is often associated with physical as well as emotional distress. Previous studies indicate a higher risk for suicide in patients diagnosed with cancer. The aim of this study was to investigate the prevalence of death by suicide in a national cohort of patients with newly diagnosed colorectal cancer compared with a matched control group to determine if patients with colorectal cancer had an increased incidence of death by suicide.

METHOD

This national Swedish cohort was retrieved from the register-based research database CRCBaSe, which includes all patients diagnosed with colorectal cancer between 1997-2006 (rectal) and 2008-2016 (colon) and six controls for each patient matched by age, sex, and county. Cause specific mortality due to suicide was modelled using Cox proportional hazards model and adjusted for known risk factors.

RESULTS

The main analysis included patients operated for colorectal cancer, 55 578 patients compared with 307 888 controls. The first year after diagnosis the hazard ratio (HR) for suicide among patients operated for colorectal cancer was 1.86 (CI: 1.18-2.95) compared to controls. Suicide was more common among men than women (HR 2.08; 1.26-3.42 vs. 1.09; 0.32-3.75). A subgroup analysis of the 9198 patients who did not undergo surgery after diagnoses found a seven-fold increase of suicide (HR 7.03; 3.10-15.91).

CONCLUSION

Suicide after surgery for colorectal cancer was almost twice as high as in the control group, mainly driven by excess mortality among men. Although the cases were few in the subgroup of nonoperated patients, the considerably higher risk of suicide indicates that more resources might be needed in this group. Evaluation of risk factors for suicide among patients with colorectal cancer should be performed for early identification of individuals at risk.

Suicide among Cancer Patients: Current Knowledge and Directions for Observational Research

Cancer is a major public health concern associated with an increased risk of psychosocial distress and suicide. The reasons for this increased risk are still being characterized. The purpose of this study is to highlight existing observational studies on cancer-related suicides in the United States and identify gaps for future research. This work helps inform clinical and policy decision-making on suicide prevention interventions and ongoing research on the detection and quantification of suicide risk among cancer patients. We identified 73 peer-reviewed studies (2010-2022) that examined the intersection of cancer and suicide using searches of PubMed and Embase. Overall, the reviewed studies showed that cancer patients have an elevated risk of suicide when compared to the general population. In general, the risk was higher among White, male, and older cancer patients, as well as among patients living in rural areas and with lower socioeconomic status. Future studies should further investigate the psychosocial aspects of receiving a diagnosis of cancer on patients' mental health as well as the impact of new treatments and their availability on suicide risk and disparities among cancer patients to better inform policies.

Suicide risk among female breast cancer survivors: A population-based study

Background

Breast cancer is the most common cancer type for females and has the highest relative number of suicide cases among female-specific cancers. This study aimed to demonstrate suicide rates and changing trends and to identify risk factors for suicide among female breast cancer survivors.

Methods

Data were derived from the surveillance, epidemiology, and end results database for women diagnosed with breast cancer from 2000 to 2017. Mortality rate and standardized mortality ratios (SMRs) were calculated to describe the incidence rate and trend of suicide among female breast cancer survivors. Gray's test and cumulative incidence function (CIF) curves were used to assess difference of cumulative suicide incidence in subgroups. Multivariate Fine-Gray competing risk model was used to identify risk factors for individual survivors and nomogram model was used to estimate the probability of suicide.

Result

There were 414 suicide cases among 638,547 female breast cancer survivors observed for 5,079,194 person-years, and the suicide rate and SMRs gradually increased with the year of diagnosis. Female breast cancer survivors had a higher risk of suicide than the general population (SMR = 1.19; 95% CI (1.08-1.31)). Based on the result of Fine-Gray competing risk models, age group (50-70 vs <50: HR=0.65, 95% CI:0.52-0.80; >70 vs <50: HR=0.22, 95% CI:0.15-0.32), race/ethnicity (black vs white: HR= 0.20, 95% CI: 0.11-0.36; other race vs white: HR= 0.67, 95% CI: 0.46-0.97), marital status (separated vs married: HR= 1.50, 95% CI: 1.16-1.94; single vs married: HR= 1.70, 95% CI: 1.31-2.20), stage (distant vs regional: HR= 0.30, 95% CI: 0.14-0.63), radiotherapy (Yes vs No/Unknown: HR= 0.62, 95% CI: 0.49-0.77), and molecular subtypes (HER-2 vs Luminal B (HR= 2.53, 95% CI: 1.10-5.82), TNBC vs Luminal B (HR= 2.11, 95% CI: 1.01-4.42)) were independent predictors of suicide among female breast cancer patients. A nomogram was constructed to predict the suicide probability for individual survivors with a C-index of 0.62 (95%CI: 0.59-0.66).

Conclusion

Female breast cancer survivors with younger age (less than 50 years old), white race, unmarried status, regional stage, HER-2 or TNBC subtype, and no radiotherapy performed were more likely to commit suicide. The clinicians and family members should pay more attention to patients with high risk factors of suicide to decrease the mortality rate.

Analysis of suicide risk in adult US patients with squamous cell carcinoma: a retrospective study based on the Surveillance, Epidemiology and End Results database

OBJECTIVES

The purpose of this study was to determine the risk factors for suicide in patients with squamous cell carcinoma (SCC) in the USA.

SETTING

Patients with SCC diagnosed between 1975 and 2017 from the Surveillance, Epidemiology and End Results (SEER) database were selected for this study.

PARTICIPANTS

This study included patients with SCC older than 20 years who were diagnosed between 1975 and 2017.

PRIMARY AND SECONDARY OUTCOME MEASURES

The general population included in data from the US Centers for Disease Control and Prevention were used to calculate the suicide rate and standardised mortality rate (SMR) of SCC patients. Univariate and multivariate Cox regression analyses were used to identify risk factors for suicide in patients with SCC.

RESULTS

There were 415 268 SCC patients registered in the SEER database, among which 1157 cases of suicide were found, comprising a total of 2 289 772 person-years. The suicide rate for patients with SCC was 50.53 per 100 000 person-years, and the SMR was 4.13 (95% CI 3.90 to 4.38). The Cox regression analyses showed that the factors related to a high risk of suicide among patients with SCC included being male (vs female: HR 5.36, 95% CI 4.51 to 6.38, p<0.001), older at the diagnosis (70-79 vs ≤39 years: HR 1.46, 95% CI 1.09 to 2.08, p=0.012; ≥80 vs ≤39 years: HR 1.48, 95% CI 1.05 to 2.08, p=0.025) and white (vs black, HR 2.97, 95% CI 2.20 to 4.02, p<0.001) and surgery (vs not performed: HR 0.65, 95% CI 0.57 to 0.74, p<0.001).

CONCLUSIONS

Compared with the general population, patients with SCC in the USA have a higher risk of suicide. Being male, older at the diagnosis, white and having a higher histological grade are risk factors for suicide in patients.

Incidence, trend and risk factors associated with suicide among patients with malignant intracranial tumors: a surveillance, epidemiology, and end results analysis

BACKGROUND

Cancer patients are associated with an elevated risk of suicide. This study aims to investigate the suicide rates and identify risk factors for suicide among patients with malignant intracranial tumors (MITs).

METHODS

Patients diagnosed with MITs during the years of 1975-2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) program. Suicide rates and standardized mortality ratios (SMR) were calculated. Cox regression analyses were used to identified risk factors for suicide among MIT patients.

RESULTS

Among 115,668 patients with MITs collected from the SEER program, 99 committed suicide. The rate of suicide was 23.02 per 100,000 person-years, and SMR of suicide was 1.90. Diagnosis in recent era (years 2000-2015, SMR = 2.01), male gender (SMR = 1.78), older age (60-79 years, SMR = 3.54), white race (SMR = 1.86), married persons (SMR = 2.31), living in rural areas (SMR = 2.50), history of other malignancy (SMR = 3.81), diagnosis of glioblastoma (SMR = 4.05) and supratentorial location (SMR = 2.45) were associated with an increased incidence of suicide. In addition, the risk of suicide increased significantly within the first year after diagnosis (SMR = 13.04). Multivariate Cox regressions showed that older age, male sex, and supratentorial location were independent risk factors for suicide.

CONCLUSIONS

The suicide mortality among patients with MITs steadily elevated in the past decades. Male sex, older age, and supratentorial location were significantly associated with risk of suicide, especially within the first year following diagnosis. Healthcare providers should early identify and effectively intervene with MIT patients at risk.

Diagnostic Performance of Diffusion-Weighted Imaging for Colorectal Cancer Detection: An Updated Systematic Review and Meta-Analysis

Background

Magnetic resonance imaging (MRI), which uses strong magnetic fields and radio waves (radiofrequency energy) to make images, is one of the best imaging methods for soft tissues and can clearly display unique anatomical structures. Diffusion-weighted imaging (DWI) has been developed for identifying various malignant tumors.

Aim

To investigate the diagnostic value of DWI-MRI quantitative analysis in colorectal cancer detection.

Methods

The PubMed, Cochrane Library, and Embase databases were searched from inception to May 29, 2020. Studies published in English that used DWI-MRI for diagnosing colorectal cancer were included. Case reports, letters, reviews, and studies conducted in non-humans or in-vitro experiments were excluded. The pooled diagnostic odds ratio (DOR) and hierarchical summary receiver operating characteristic (HSROC) curves were computed for DWI, and the area under the curve (AUC) and associated standard error (SE) and 95% confidence intervals (CIs) were also used.

Results

In total, 15 studies with 1,655 participants were finally included in this meta-analysis. There were four prospective studies and 11 retrospective studies. Eight studies focused on rectal cancer, six on colorectal cancer, and one on colonic cancer. The performance of DWI-MRI for diagnosing colorectal cancer was accurate, with pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 0.88 (95% CI = 0.85–0.91), 0.92 (95% CI = 0.91–0.94), 30.36 (95% CI = 11.05–83.43), and 0.44 (95% CI = 0.30–0.64), respectively. The DOR and HSROC curves were 121 (95% CI = 56–261) and 0.92 (λ: 4.79), respectively.

Conclusion

DWI showed high diagnostic accuracy for colorectal cancer detection. Further studies with large sample sizes and prospective design are needed to confirm these results.

Prevalence and risk factors for suicidality in cancer patients and oncology healthcare professionals strategies in identifying suicide risk in cancer patients

PURPOSE OF REVIEW

The aim of this study was to summarize the literature on prevalence and risk factors for suicidality in cancer patients and to document the research on oncology healthcare professionals' strategies in identifying this risk.

RECENT FINDINGS

Cancer patients exhibit increased risk of suicidality compared with the general population. Various risk factors have been identified including sociodemographic factors such as poverty, being male and elderly as well as disease-related attributes such as cancer type and stage. The literature on how healthcare professionals identify suicide risk is sparse. Ten articles were found that focused on two main themes. These included information on systematic strategies in identifying suicide risk and factors that affect healthcare professionals' ability to identify risk in their patients.

SUMMARY

Although there is an immense amount of literature documenting the problem of suicidality among patients, the research on how healthcare professionals identify and respond to these indications in patients is nearly nonexistent. Cancer centres should implement standardized and systematic screening of cancer patients for suicidality and research on this patient population should collect and report these data. Ongoing training and education for healthcare professionals who work in the oncology setting on how to identify and respond to suicide risk among cancer patients is urgently needed.

Treatment response prediction using MRI-based pre-, post-, and delta-radiomic features and machine learning algorithms in colorectal cancer

OBJECTIVES

We evaluate the feasibility of treatment response prediction using MRI-based pre-, post-, and delta-radiomic features for locally advanced rectal cancer (LARC) patients treated by neoadjuvant chemoradiation therapy (nCRT).

MATERIALS AND METHODS

This retrospective study included 53 LARC patients divided into a training set (Center#1, n = 36) and external validation set (Center#2, n = 17). T2-weighted (T2W) MRI was acquired for all patients, 2 weeks before and 4 weeks after nCRT. Ninety-six radiomic features, including intensity, morphological and second- and high-order texture features were extracted from segmented 3D volumes from T2W MRI. All features were harmonized using ComBat algorithm. Max-Relevance-Min-Redundancy (MRMR) algorithm was used as feature selector and k-nearest neighbors (KNN), Naïve Bayes (NB), Random forests (RF), and eXtreme Gradient Boosting (XGB) algorithms were used as classifiers. The evaluation was performed using the area under the receiver operator characteristic (ROC) curve (AUC), sensitivity, specificity and accuracy.

RESULTS

In univariate analysis, the highest AUC in pre-, post-, and delta-radiomic features were 0.78, 0.70, and 0.71, for GLCM_IMC1, shape (surface area and volume) and GLSZM_GLNU features, respectively. In multivariate analysis, RF and KNN achieved the highest AUC (0.85 ± 0.04 and 0.81 ± 0.14, respectively) among pre- and post-treatment features. The highest AUC was achieved for the delta-radiomic-based RF model (0.96 ± 0.01) followed by NB (0.96 ± 0.04). Overall. Delta-radiomics model, outperformed both pre- and post-treatment features (P-value <0.05).

CONCLUSION

Multivariate analysis of delta-radiomic T2W MRI features using machine learning algorithms could potentially be used for response prediction in LARC patients undergoing nCRT. We also observed that multivariate analysis of delta-radiomic features using RF classifiers can be used as powerful biomarkers for response prediction in LARC.

Transcriptome profiling unveils GAP43 regulates ABC transporters and EIF2 signaling in colorectal cancer cells

Background

The growth- and plasticity-associated protein-43 (GAP43) is biasedly expressed in indigestive system and nervous system. Recent study has shown that GAP43 is responsible for the development of neuronal growth and axonal regeneration in normal nervous tissue, while serves as a specific biomarker of relapsed or refractory neuroblastoma. However, its expression pattern and function in digestive system cancer remains to be clarified.

Methods

In this study, we examined the GAP43 status with qRT-PCR and bisulfite genomic sequencing in colorectal cancer (CRC). We investigated the effect of overexpressed GAP43 in CRC cells with RNA-seq. The RNA-seq data was analyzed with DAVID and IPA.

Results

GAP43 was downregulated in CRC compared to the adjacent tissues. DNA methylase inhibitor 5-Aza-CdR treatment could significantly induce GAP43, indicated that the silencing of GAP43 gene in CRC is closely related to DNA methylation. Bisulfite genomic sequencing confirmed the promoter methylation of GAP43 in CRC. To explore the transcriptional alterations by overexpressed GAP43 in CRC, we performed RNA-seq and found that upregulated genes were significantly enriched in the signaling pathways of ABC transporters and ECM-receptor interaction, while downregulated genes were significantly enriched in Ribosome signaling pathway. Further Ingenuity Pathway Analysis (IPA) showed that EIF2 signaling pathway was significantly repressed by overexpression of GAP43.

Conclusion

Our findings provide a novel mechanistic insight of GAP43 in CRC. Transcriptome profiling of overexpressed GAP43 in CRC uncovered the functional roles of GAP43 in the development of human CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-020-07728-x.

Incidence of suicide death in patients with cancer: A systematic review and meta-analysis

BACKGROUND

Growing evidence indicated the higher risk of suicide in cancer survivors compared with general population. Our aim is to systematically quantify the extent of suicide death and identify risk factors associated with the incidence of suicide in cancer patients.

METHODS

We conducted a meta-analysis of relevant studies published in English or Chinese before May 20, 2020. Suicide rate and the number of suicide death were extracted. Our main outcome was suicide rate per 100,000 person-years with 95% CIs using random-effects model.

RESULTS

The pooled incidence of suicide death was 39.72 per 100,000 person-years (95%CI, 33.91-46.52, I ²= 99.6%, P <0 .001). The suicide rate for cancer patients was higher in men (57.78, 95%CI, 47.31-70.56) than in women (14.47, 95%CI, 11.27-18.57). For both sexes combined, esophagus cancer had the highest rate of suicide (87.71, 95%CI, 27.42-280.54). By sex, suicide rates ranked first in males and females were pancreas cancer (195.70, 95%CI, 129.55-295.61) and esophagus cancer (18.34, 95%CI, 5.92-56.84), respectively. The highest suicide rate was 61.02(95%CI, 53.66-69.40) in Asia, and Oceania (24.07, 95%CI, 20.78-27.88) had lowest suicide rate. Suicide rate had a downward trend by years after diagnosis, with the first six months after cancer diagnosis clearly standing out (89.33, 95%CI, 50.64-157.58).

LIMITATIONS

Included studies came from high-income countries and our results might not represent the suicide rate among cancer patients in low- and middle-income countries.

CONCLUSIONS

The incidence of suicide among cancer patients was high despite the declined trend recent years, which emphasized psychological health aspects of interventions and perfecting suicide prevention programs.

Marital status, an independent predictor for survival of gastric neuroendocrine neoplasm patients: a SEER database analysis

BACKGROUND

Marital status proves to be an independent prognostic factor in a variety of cancers. However, its prognostic impact on gastric neuroendocrine neoplasms (G-NEN) has not been investigated.

METHODS

We identified 3947 G-NEN patients from the Surveillance, Epidemiology, and End Results (SEER) database. Meanwhile, propensity scores for marital status were used to match 506 unmarried patients with 506 married patients. We used Kaplan-Meier method and multivariate Cox regression to analyse the association between marital status and the overall survival (OS) and G-NEN cause-specific survival (CSS) before matching and after matching.

RESULTS

Married patients enjoyed better OS and CSS, compared with divorced/separated, single, and widowed patients. Multivariate Cox regression analysis indicated that unmarried status was associated with higher mortality hazards for both OS and CSS among G-NEN patients. Additionally, widowed individuals had the highest risks of overall (adjusted hazard ratio (HR): 1.56, 95% confidence interval (CI): 1.35-1.81, P < 0.001) and cancer-specific mortality (adjusted HR: 1.33, 95% CI: 1.05-1.68, P = 0.02) compared to other unmarried groups in both males and females. Furthermore, unmarried status remained an independent prognostic and risk factor for both OS (HR 1.51, 95% CI 1.19-1.90, P = 0.001) and CSS (HR 1.50, 95% CI 1.10-2.05, P = 0.01) in 1:1 propensity score-matched analysis.

CONCLUSION

Marital status was an independent prognostic factor for G-NEN. Meanwhile, widowed patients with G-NEN had the highest risk of death compared with single, married, and divorced/separated patients.

The Role and Mechanism of S1PR5 in Colon Cancer

Purpose

To investigate the role and mechanism of S1PR5 in colon cancer.

Materials and Methods

Lentiviral infection and drug screening helped to establish colon cancer cell lines with stable overexpression and knockdown of S1PR5. Effects of S1PR5 expression on cell growth, proliferation, migration, and invasion were analyzed using a subcutaneous xenograft model in nude mice. Western blot (WB) was used to detect the effects of S1PR5 expression on p-AKT, STAT3, NF-κB, and p-JNK. The distribution of p65 was evaluated in nuclear and cytoplasmic fractions using WB. CCK-8, Transwell migration, and Transwell invasion assays analyzed cell growth, proliferation, migration, and invasion. qRT-PCR analysis revealed that S1PR5 expression was associated with altered expression levels of NF-κB downstream target genes, such as IL-6, TNF-α, and indoleamine 2, 3-dioxygenase 1 (IDO1).

Results

qRT-PCR and WB analysis showed that the S1PR5 level in colon cancer cell lines-SW480, SW620, HCT116, and LoVo-was significantly higher than in NCM460, a healthy colonic epithelial cell line. SW620 and SW480, with high and low expression of S1PR5, respectively, were selected as model cell lines. S1PR5 knockdown in SW620 caused the growth rate, proliferation, migration, invasion, and subcutaneous tumor formation rate to decrease in mice, whereas S1PR5 overexpression in SW480 caused all of these parameters to increase. WB analysis showed an increase in phospho-p65 and its nuclear translocation. S1PR5 knockdown caused a decrease in phospho-p65 levels and its nuclear import, thereby inhibiting its activity. In S1PR5 knockdown and overexpressing cells, p65 was overexpressed and knocked down, respectively. qRT-PCR and WB showed that S1PR5 over-expression up-regulates IDO1, and S1PR5 knockdown inhibits IDO1. CCK-8 and Transwell assays showed that p65 and IDO1 overexpression antagonizes the antitumor effect of S1PR5 knockdown, and that p65 and IDO1 knockdown antagonizes the tumorigenic effect of S1PR5 overexpression.

Conclusion

S1PR5 overexpression promotes the growth, migration, and invasion of cancer by activating the NF-κB/IDO1 signaling pathway.

Suicide among cancer patients: adolescents and young adult (AYA) versus all-age patients

Background

Many researchers have studied suicide risk factors of patients with one specific cancer. But there is no comprehensive study to compare suicide issues between adolescents and young adult (AYA) group and all-age groups in a pan-cancer view.

Methods

Patients diagnosed with 20 solid malignancies were identified from SEER database. Multivariable logistic regression was operated to find out risk factors of suicide.

Results

Male sex has less impact on AYA than all-age patients (OR 2.72, 95% CI: 2.23-3.31, P<0.001 vs. OR 4.64, 95% CI: 4.37-4.94, P<0.001), while white race (OR 3.28, 95% CI: 2.02-5.77, P<0.001 vs. OR 3.40, 95% CI: 3.02-3.84, P<0.001) and unmarried status (OR 1.51, 95% CI: 1.24-1.83, P<0.001 vs. OR 1.39, 95% CI: 1.33-1.46, P<0.001) have similar impact on AYA and all-age groups. Localized cancer stage may have stronger impact on AYA than all-age (OR 2.90, 95% CI: 1.83-4.84; P<0.001 vs. OR 1.76, 95% CI: 1.61-1.92; P<0.001), while surgery only influence all-age (OR 1.14, P=0.451 vs. 1.24, P<0.001). Within 5 years from cancer diagnosis, longer survival time is associated with higher suicide risk of both all-age and AYA patients.

Conclusions

Male sex, white race and unmarried status, earlier cancer stage and longer survival time within 5 years are similar prevalent risk factors for both AYA group patients and all-age patients. It is not necessary to pick AYA cancer patients out when considering suicide risk of cancer patients.

Risk factors associated with suicide among kidney cancer patients: A Surveillance, Epidemiology, and End Results analysis

Background

The suicide risk was higher in kidney cancer patients than in the general population. The purpose of this study was to characterize the suicide rates among kidney cancer patients and to identify the potential risk factors associated with suicide from the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

Kidney cancer patients were identified from the SEER database during 1973‐2015. Suicide rates and standardized mortality ratios (SMRs) of this population were calculated, and the US general population during 1981‐2015 was chosen as a reference. Univariable and multivariable Cox regression were performed to find out potential risk factors of suicide.

Results

There were 207 suicides identified among 171 819 individuals with kidney cancer observed for 948 272 person‐years. The suicide rate was 21.83 per 100 000 person‐years, and SMR was 1.83 (95% CI: 1.59‐2.10). On Cox regression, diagnosis in early years (1973‐1982 vs 2003‐2015, HR: 2.03, 95% CI: 1.01‐4.11, P = 0.048; 1983‐1992 vs 2003‐2015, HR: 1.99, 95% CI: 1.18‐3.35, P = 0.010), male sex (vs female sex, HR: 4.43, 95% CI: 2.95‐6.65, P < 0.001), unmarried status (vs married status, HR: 2.54, 95% CI: 1.91‐3.38, P < 0.001), non‐black race (white race vs black race, HR: 4.47, 95% CI: 2.09‐9.58, P < 0.001; other races vs black race, HR: 3.01, 95% CI: 1.08‐8.37, P = 0.035), higher histologic grade (grade IV vs grade I, HR: 3.27, 95% CI: 1.50‐7.13, P = 0.003; grade III vs grade I, HR: 2.13, 95% CI: 1.19‐3.81, P = 0.011) and cancer‐directed surgery not performed (vs performed, HR: 2.78, 95% CI: 1.52‐5.11, P < 0.001) were independent risk factors of suicide among kidney cancer patients.

Conclusions

Diagnosis in early years, male sex, unmarried status, non‐black race, higher histologic grade, and cancer‐directed surgery not performed were significantly associated with suicide among kidney cancer patients. In order to prevent suicidal death, clinicians should pay more attention to patients with high‐risk factors of suicide.

Suicide risk among colorectal cancer patients in Lithuania

PURPOSE

We aimed to estimate suicide risk among colorectal cancer patients in the country showing the highest suicide rates among developed countries.

METHODS

Patients with colorectal cancer diagnosed between 1998 and 2012 were identified from the Lithuanian Cancer Registry. Standardised mortality ratios (SMRs) for suicide were calculated for patients diagnosed with cancer in Lithuania, relative to suicide rates in the general population.

RESULTS

Twenty thousand seven hundred sixty-five primary colorectal cancer cases diagnosed between 1998 and 2012 were extracted from the database. Among 19,409 first primary colorectal cancer patients, we identified 67 suicides and the expected number of suicides calculated from general population was 41.4 in this cohort, resulting in an SMR of 1.62 for both sexes (95% CI, 1.27-2.06). A higher suicide risk was found for women (SMR 2.15; 95% CI 1.35-3.41), than for men (SMR 1.48; 95% CI 1.12-1.96). The suicide risk was almost twice higher in patients 60 and older, with highest increase in the oldest patients (SMR 2.12, 95% CI 1.01-4.46). The risk of suicide was not significantly elevated in colorectal cancer patients with localised tumours, but there was a fourfold increase in risk in patients with stage IV tumours. Compared with the general population, the risk of suicide among colorectal cancer patients was four times higher during the first 3 months after diagnosis and decreased thereafter.

CONCLUSIONS

The patients with colorectal cancer have a higher rate of suicide compared with the general Lithuanian population. Sex, age, advanced rectal cancer and distant spread of disease were the main predictors of suicide among colorectal cancer patients.