Prognostic factors and survival of colorectal cancer in Kurdistan province, Iran: A population-based study (2009-2014)

Survival rate of colorectal cancer in China: A systematic review and meta-analysis

Background

This study aims to comprehensively summarize the colorectal survival rate in China. Method: In PubMed and Web of Science, keywords such as "colorectal cancer", "survival" and "China" were used to search literatures in the past 10 years. Random effect models were selected to summarize 1-year, 3-year, and 5-year survival rates, and meta-regression and subgroup analyses were performed on the included studies.

Results

A total of 16 retrospective and prospective studies providing survival rates for colorectal cancer in China were included. The 1-year, 3-year, and 5-year survival rates of colorectal cancer in China were 0.79, 0.72 and 0.62, respectively. In the included studies, the 5-year survival rates of stage I (5474 cases), stage II (9215 cases), stage III (8048 cases), and stage IV (4199 cases) colorectal cancer patients were 0.85, 0.81, 0.57 and 0.30, respectively. Among them, the 5-year survival rates of colorectal cancer were 0.82, 0.76, 0.71, 0.67, 0.66, 0.65 and 0.63 in Tianjin, Beijing, Guangdong, Shandong, Liaoning, Zhejiang and Shanghai, respectively.

Conclusion

The 5-year survival rate in China is close to that of most European countries, but still lower than Japan and South Korea, and the gap is gradually narrowing. Region, stage, differentiation, pathological type, and surgical approach can affect 5-year survival in colorectal cancer.

Systematic review registration

https://www.crd.york.ac.uk/prospero/ identifier, CRD42022357789.

Advanced stage presentation and its determinant factors among colorectal cancer patients in Amhara regional state Referral Hospitals, Northwest Ethiopia

INTRODUCTION

Nowadays, the burden of colorectal cancer (CRC) has been increasing in the world, particularly in developing nations. This could be related to the poor prognosis of the disease due to late presentation at diagnosis and poor treatment outcomes. In Ethiopia, studies related to the stage of colorectal cancer at diagnosis and its determinants are limited. Therefore, the study was intended to assess advanced stage presentation and its associated factors among colorectal cancer patients in northwest Ethiopia.

METHODS

An institution-based retrospective study was conducted among 367 CRC patients at two oncologic centers (the University of Gondar and Felege Hiwot comprehensive specialized hospitals) from January 1, 2017, to December 31, 2020. Data were entered into EPi-data 4.2.0.0 and transferred to STATA version 14 statistical software for analysis. Binary logistic regression was used to identify factors associated with the outcome variable. All variables with P-value < 0.2 during bi-variable analysis were considered for multivariable logistic regression. The level of statistical significance was declared at P-value <0.05.

RESULTS

The magnitude of advanced stage presentation of colorectal cancer was 83.1%. Being rural dwellers (Adjusted odds ratio (AOR) = 3.6; 95% CI: 1.8,7.2), not medically insured (AOR = 3.9; 95% CI: 1.9,7.8), patients delay (AOR = 6.5; 95% CI:3.2, 13.3), recurrence of the disease (AOR = 2.3; 95% CI: 1.1,4.7), and no comorbidity illness (AOR = 4.4; 95% CI: 2.1, 9.1) were predictors of advanced stage presentation of CRC.

CONCLUSION

The current study revealed that the advanced-stage presentation of colorectal cancer patients was high. It is recommended that the community shall be aware of the signs and symptoms of the disease using different media, giving more emphasis to the rural community, expanding health insurance, and educating patients about the recurrence chance of the disease. Moreover, expansion of colorectal treatment centers and screening of colorectal cancer should be given emphasis.

Prognostic Factors for Survival of Colorectal Adenocarcinoma Patients in Uganda

Background

In Uganda, similar to other countries in East Africa, the incidence of colorectal cancer (CRC) has been steadily increasing. This increase in incidence is accompanied by a poor prognosis. There is limited knowledge on factors responsible for the poor outcome of patients with CRC in Uganda. Cancer survival analysis is one way of determining some of these prognostic factors. The aim of this study was to determine prognostic factors associated with CRC survival in Ugandan patients.

Methods

This was a retroprospective cohort study involving patients with linked data in the Kampala cancer registry and medical records from hospitals in Uganda. Participants with a diagnosis of colorectal adenocarcinoma between 1st January 2008 and 31st December 2018 were included. Variables included patients’ demographic data, grade, stage and location of CRC, data on whether a patient was operated on, type of operation, treatment modalities and date of diagnosis. Our outcome variable was time to death after diagnosis. We computed and compared survival using the Log rank test and used Cox proportional hazards regression to determine factors associated with survival.

Results

A total of 247 patients were included in the study with a mean (SD) age of 53.3 (15.7) years and a female: male ratio of 1.14:1. The proportions of patients surviving at 1, 2 and 3 years were 65.2% (95% CI: 58.8–70.9), 42.0% (95% CI:35.6–48.3) and 33.3% (95% CI:27.3–39.4) respectively. In multivariate analysis, factors associated with increased mortality included clinical stage II (aHR = 2.44, 95% CI: 1.10–5.41, p=0.028), stage III (aHR=2.65, 95% CI: 1.31–5.39, p=0.007) and stage IV (aHR=5.47, 95% CI: 2.40–12.48, p<0.001). Curative surgery alone (aHR=0.63, 95% CI: 0.39–1.01, p=0.057) and curative surgery with chemotherapy (aHR=0.53, 95% CI: 0.32–0.88, p=0.015) were associated with a better survival.

Conclusion

The survival rate among CRC patients in Uganda is low. Advanced stage CRC accelerates mortality, while surgery alone or in combination with chemotherapy improves survival. Implementation of national screening programmes for early diagnosis of CRC and increasing surgery and oncology infrastructure is recommended to improve the CRC survival rate in the Ugandan population.

Overall survival and prognostic factors prostate cancer in Kurdistan Province-Iran: a population-based study (2011-2018)

Background

The population-based survival rate is affected by the quality and effectiveness of health care systems. Overall, the survival of prostate cancer (PC) patients has improved over the past two decades worldwide. This study aimed to determine the overall survival rate and correlate it with the prognostic factors in patients with PC diagnosed in Kurdistan province.

Methods

In a retrospective cohort study, 410 PC patients registered in Kurdistan province population-based cancer registry from March 2011 to 2018 were recruited. Kaplan–Meier method and log-rank test were used to analyze the overall survival rates of PC patients. A Multivariate Cox regression model was used to determine adjusted hazard ratios for different variables.

Results

Of 410 patients with PC, 263 (64.1%) died within seven years due to the disease. The 1, 3, and 5 years survival rates were 93, 64.1, and 40.7%, respectively. According to the results of multiple Cox regression, the following factors were significantly related to PC survival: age at diagnosis (≥81-years old) (HR=2.23, 95% CI: 1.23-4.42) and 71-80 years old was (HR=1.26, 95% CI: 1.12-2.31), occupation (employee) (HR=0.42, 95% CI: 0.20–0.87), educational level: academic (HR=0.78, 95% CI: 0.64–0.91), AJCC stage of disease (HR=2.18, 95% CI: 1.9–3.68), Gleason score ≥ 9 (HR=7.12, 95% CI: 5.35–10.28), and Gleason score= 8 (HR=4.16, 95% CI: 2.50–6.93). There was less mortality rate among the patients who had received active care, radical prostatectomy, radiotherapy, combined treatment, and orchiectomy had a lower mortality rate than those who received no treatment (P<0.05).

Conclusions

This study demonstrated that factors such as age at diagnosis, level of education, occupation, AJCC stage of disease, Gleason score, and type of treatments were influential factors in the survival of PC patients in Kurdistan province and needed more attention.

The combined effect of dichloroacetate and 3-bromopyruvate on glucose metabolism in colorectal cancer cell line, HT-29; the mitochondrial pathway apoptosis

Background

5-Fluorouracil (5-FU) is regarded as the first line treatment for colorectal cancer; however, its effectiveness is limited by drug resistance. The ultimate goal of cancer therapy is induction of cancer cell death to achieve an effective outcome with minimal side effects. The present work aimed to assess the anti-cancer activities of mitocans which can be considered as an effective anticancer drug due to high specificity in targeting cancer cells.

Methods

MTT (3–4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) assay was performed to determine the effects of our mitocans on cell viability and cell death. Apoptosis and necrosis, caspase 3 activity, mitochondrial membrane potential and ROS production in HT29 cell lines were analyzed by ApopNexin™ FITC/PI Kit, Caspase- 3 Assay Kit, MitoTracker Green and DCFH-DA, respectively. Moreover, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression level of pro-apoptotic (Bax) and anti-apoptotic (Bcl-2) genes in HT29 cell lines.

Results

Treatment with mitocans (3Br-P + DCA) inhibited the growth of HT29. Moreover, 3Br-P + DCA significantly induced apoptosis and necrosis, activation of caspase 3 activity, depolarize the mitochondrial membrane potential, and ROS production. At a molecular level, 3Br-P + DCA treatment remarkably down-regulated the expression of Bcl-2, while up-regulated the expression of Bax.

Conclusion

Mitocans, in particular the combined drug, 3Br-P + DCA, could be regarded and more evaluated as a safe and effective compound for CRC treatment. Targeting hexokinase and pyruvate dehydrogenase kinase enzymes may be an option to overcome 5-FU -mediated chemo-resistant in colorectal cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08564-3.

Histological characteristics, survival pattern and prognostic determinants among colorectal cancer patients in Ethiopia: A retrospective cohort study

Background

The incidence of colorectal cancer (CRC) and associated mortality are rising in low- and middle-income countries. In Ethiopia, colorectal cancer is among the leading causes of cancer morbidity and mortality in both sexes. Although some studies provided estimations on the national burden and regional distribution, the histological characteristics, survival pattern and determinants among colorectal cancer patients are not well-documented.

Aim

This study aimed to describe the histological characteristics, to determine the patterns of survival, and identify factors that determine mortality rate among CRC patients in Ethiopia.

Methods

A retrospective cohort study was conducted among CRC patients registered at cancer treatment center of Tikur Anbessa Specialized Hospital, from January 2012 to December 2016. Data were extracted from a total of 161 patient medical records using a pretested abstraction form and supplemented by phone calls with the patients/caregivers. To determine colorectal cancer specific survival overtime, we performed a Kaplan-Meier survival analysis and significance of variation in survival across covariates and treatment categories was tested using log-rank test. A multivariable Cox proportional-hazards model was performed to identify determinants of survival after diagnosis with colorectal cancer.

Results

Overall, the median survival time was 21 months [95%CI: 16-35], with two-, three- and five-year CRC-specific survival rates of 46.8%, 39.5% and 28.7% respectively. In the multivariable Cox regression model, the rate of death due to CRC is significantly higher for patients with elevated baseline carcinoembryonic antigen (CEA) level (Adjusted Hazard Ratio (AHR) = 2.31, 95%CI: 1.27-4.19), stage IV at diagnosis (AHR = 2.66, 95%CI: 1.44-4.91), and mucinous or signet-ring cell carcinoma histology type (AHR = 4.92, 95%CI: 1.75-13.80). Moreover, patients who underwent surgery showed a better survival than those who did not (AHR = 0.35, 95%CI: 0.14-0.88).

Conclusion

In Ethiopia, patients diagnosed with CRC showed a low rate of cancer-specific survival. Histology type, stage of cancer and CEA level at diagnosis, and the type of treatment a patient received significantly determine mortality rate. Hence, cancer screening programs could help to detect the disease at an earlier stage and to initiate available treatments timely so as to extend the lifespan of CRC patients.

Associated Factors of Survival Rate and Screening for Colorectal Cancer in Iran: a Systematic Review

PURPOSE

Colorectal cancer (CRC) is one of the most important cancers, which has various patterns in the world. The aim of this study was to determine the factor associated to survival and looking for screening in Iran.

METHODS

A literature search was conducted using PubMed, Web of Science, Scopus, SID, and Magiran on June 30, 2018. Studies that performed survival analysis and the barrier of screening for colorectal cancer were included in this review.

RESULTS

Fifty-three articles for survival and 11 for screening were included and examined. The important factors of survival are the age, cancer stage, tumor grade, ethnicity, marital status, family history of cancer, smoking, metastasis, and obesity. For barrier of screening, the cost, shame, fear of diagnosis the cancer, absence of clinical symptoms, and time limit were determined.

CONCLUSION

Remarkably, knowledge, attitude, and behaviors about CRC screening in Iran are very moderate to poor. According to diversity of survival rates and low tendency to screening, we need to further and deepen studies of barrier and facilitators of screening.

Prognosis of colorectal cancer in Tikur Anbessa Specialized Hospital, the only oncology center in Ethiopia

Introduction

Colorectal cancer is the third most commonly diagnosed cancer in males and the second in females worldwide. According to the Addis Ababa cancer registry, it is the first in male and fourth in female in Ethiopia. However, there have not been studies on prognostic factors and survival of colorectal cancer. Hence, this study aimed to estimate survival time and identify prognostic factors.

Methods

In this institution based retrospective study, medical records review of 422 colorectal cancer patients and telephone interview was used as sources of data. Survival time was estimated using Kaplan-Meier estimator. Prognostic factors were identified using the multivariable Cox regression model.

Results

Patients diagnosed with rectal cancer had 76% (HR: 1.761, 95% CI: 1.173–2.644) increased risk of dying compared to colon cancer patients. Node positive patients were 3.146 (95% CI: 1.626–6.078) times likely to die compared to node-negative and metastatic cancer were 4.221 (95% CI: 2.788–6.392) times likely to die compared to non-metastatic patients. Receiving adjuvant therapy reduced the risk of death by 36.1% (HR: 0.639 (95% CI: 0.418–0.977)) compared to patients who had an only surgical resection. The median survival time was 39 months and the overall five years survival rate was 33%.

Conclusions

The overall survival rate was low and a majority of the patients were young at presentation. Patient’s survival is largely influenced by the advanced cancer stage at presentation and delays in the administration of adjuvant therapy. Receiving adjuvant therapy was among the good prognostic factors.

A nomogram based on pretreatment levels of serum bilirubin and total bile acid levels predicts survival in colorectal cancer patients

Background

Serum bilirubin and total bile acid (TBA) levels have been reported to be strongly associated with the risk and prognosis of certain cancers. Here, we aimed to investigate the effects of pretreatment levels of serum bilirubin and bile acids on the prognosis of patients with colorectal cancer (CRC).

Methods

A retrospective cohort of 1474 patients with CRC who underwent surgical resection between January 2015 and December 2017 was included in the study. Survival analysis was used to evaluate the predictive value of pretreatment levels of bilirubin and bile acids. X-Tile software was used to identify optimal cut-off values for total bilirubin (TBIL), direct bilirubin (DBIL) and TBA in terms of overall survival (OS) and disease-free survival (DFS).

Results

DBIL, TBIL, and TBA were validated as significant prognostic factors by univariate Cox regression analysis for both 3-year OS and DFS. Multivariate Cox regression analyses confirmed that high DBIL, TBIL and TBA levels were independent prognostic factors for both OS (HR: 0.435, 95% CI: 0.299–0.637, P < 0.001; HR: 0.436, 95% CI: 0.329–0.578, P < 0.001; HR: 0.206, 95% CI: 0.124–0.341, P < 0.001, respectively) and DFS (HR: 0.583, 95% CI: 0.391–0.871, P = 0.008; HR:0.437,95% CI: 0.292–0.655, P <0.001; HR: 0.634, 95% CI: 0.465–0.865, P = 0.004, respectively). In addition, nomograms for OS and DFS were established according to all significant factors, and the c-indexes were 0.819 (95% CI: 0.806–0.832) and 0.835 (95% CI: 0.822–0.849), respectively.

Conclusions

TBIL, DBIL and TBA levels are independent prognostic factors in colorectal cancer patients. The nomograms based on OS and DFS can be used as a practical model for evaluating the prognosis of CRC patients.

Prognostic Factors of Rectal Cancer in Southern Iran

BACKGROUND

Rectal cancer accounts for one-third of all colorectal cancer (CRC) cases. Due to physiological and anatomical differences, some researchers consider rectal cancer as a separate organ malignancy during the recent decades. However, limited studies have been conducted in this regard in Iran. Therefore, the aim of this study is to determine survival of rectal cancer and its^, affecting factors in Fars province, southern Iran.

METHODS

In this cohort study, we used the data of 387 patients with rectal cancer gathered by the Colorectal Research Center of Shiraz University of Medical Sciences between 2007 and 2015. The impact of 35 explanatory factors including demographic information, medical history, pathologic data, and imaging findings was evaluated using Cox regression analysis.

RESULTS

Out of all patients, 111 ones (29%) died. The median follow-up period was 36 months. The patients' mean age at diagnosis was 56.72 ± 13.89 years. Their 5-year survival was 65% (95% CI: 58-69%). The results of multiple Cox regression analysis showed that sex (male/female; HR = 1.73, 95% CI: 1.15-2.67), vascular invasion (yes/no; HR = 2.40, 95% CI: 1.45-3.99), and lymph node ratio (> 0.2 vs ≤ 0.2; HR = 2.19, 95% CI: 1.41-3.40) were significantly correlated to survival.

CONCLUSION

Various geographical parts of Iran show different rates regarding rectal cancer survival. A better 5-year survival rate was detected by this study for the patients with rectal cancer in Fars province, southern Iran, compared to many parts of the country. Moreover, gender, vascular invasion, and nodal status played an important role in survival of rectal cancer.

Factors associated with the survival of colorectal cancer in Mexico

BACKGROUND/AIMS

Colorectal cancer (CRC) is a public health problem. In Mexico, there have been no recent studies conducted on survival in terms of this pathology or on the influence of prognostic factors. The study aims to determine the probability of survival in patients with CRC presence of low levels of schooling and a rural population, adjusted for clinical stage and type of treatment.

METHODS

A retrospective study was conducted in a cohort of 305 patients with CRC treated at State Cancer Center, located in Veracruz-Mexico; the follow-up period of 60 months (2012-2016). The survival probability was calculated using the Kaplan-Meier estimator and the log-rank test with 95% confidence intervals (CIs). Prognostic factors were determined using hazard ratio (HR) multivariate Cox regression analysis.

RESULTS

Overall survival was 40% at 60 months. Subjects in the age group ≥ 65 years had a low survival rate of 28% (P= 0.026) and an advanced clinical stage of 22% (P< 0.001). Of the patients with bone metastasis, none survived longer than 5 years (P= 0.008). With respect to the unfavorable prognostic factors identified in the multivariate analysis, a decreased level of schooling was associated with an HR of 7.6 (95% CI, 1.1-54.7), advanced clinical stage was associated with an HR of 2.1 (95% CI, 1.2-4.0), and the presence of metastasis had an HR of 1.8 (95% CI, 1.1-2.9).

CONCLUSIONS

Poor prognostic factors include an advanced clinical stage, the presence of metastasis and a low level of schooling. These findings confirm the importance of screening for early diagnosis, diminishing the barriers to accessing treatment and prospectively monitoring the population.

Survival Status and Predictors of Mortality Among Colorectal Cancer Patients in Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia: A Retrospective Followup Study

Colorectal cancer is one of the commonest cancer types that has a great public health impact both in developed and developing countries. However, in Ethiopia, the survival status of colorectal cancer patients was not well understood. Therefore, the aim of this study was to determine the survival status and predictors of mortality among colorectal cancer patients in Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia in 2019. The institution-based retrospective follow-up study was conducted with 621 subjects who were selected from patients registered between January 1, 2013 and December 30, 2017 with follow-up until December 30th, 2018. Data were collected from patient record review charts. A Kaplan-Meier analysis with a log-rank test, and bivariate and multivariable analysis using the Cox proportional hazard model were used. Of the 621 colorectal cancer patients who were included in the analysis, 202 (32.5%) died. The overall mortality rate was 20.3% per year (95% CI: 17.7-23.3). The overall survival was 18.1% with median survival time of 34.8 months (95% CI: 30.4-36.8). Comorbidity (adjusted hazard ratio [AHR] = 1.8, 95% CI: 1.3-2.5); stage (II [AHR = 3.8, 95% CI: 1.3-11.1], III [AHR = 8.0, 95% CI: 2.8-23.3], IV [AHR = 17.6, 95% CI: 6.1-50.7]); smoking (AHR = 1.6, 95% CI: 1.1-2.3); alcohol consumption (AHR = 1.5, 95% CI: 1.07-2.2); age ≥ 70 (AHR = 1.7, 95% CI: 1.02-2.9); and marital status (married [AHR = 2.4, 95% CI: 1.5-3.8], widowed [AHR = 2.4, 95% CI: 1.2-4.6], divorced [AHR = 2.0, 95% CI: 1.1-3.7]) were significant predictors of colorectal cancer mortality. It is crucial to implement early detection and screening, giving priority to rural dweller, comorbid patients and advanced stage diagnosed patients.

Survival Rate of Colorectal Cancer in Eastern Mediterranean Region Countries: A Systematic Review and Meta-Analysis

Colorectal cancer (CRC) is the second most common cause of cancer-related deaths worldwide. Survival rates are among the most important factors in quality control and assessment of treatment protocols. This study was aimed to assess the survival rate of colorectal cancer in Eastern Mediterranean Region Countries. In the present study we comprehensively searched 6 international databases including PubMed/Medline, ProQuest, Scopus, Embase, Web of Knowledge and Google Scholar for published articles until November 2018. The Newcastle-Ottawa Quality Assessment Form for Cohort Studies was applied to evaluate the quality of included studies. The heterogeneity of papers was assessed with the Cochran Test and I-Square statistics. Meta-regression test was performed based on publication year, sample size and Human Development Index (HDI) of each study. Among the total of 1023 titles found in the systematic search, 43 studies were eligible to be included in the present meta-analysis. According to the results, the 1-year, 3-year and 5-year survival rate of patients with Colorectal Cancer was 88.07% (95% CI, 83.22-92.92), 70.67% (95% CI, 66.40-74.93) and, 57.26% (95% CI, 50.43-64.10); respectively. Furthermore, Meta-regressions did not show significant correlations between survival rate and year, sample size or Human Development Index. Survival rates, especially the 5-year survival rate in the EMRO were less than European countries and the USA. Documented and comprehensive evidence-based findings of the present meta-analysis can be used to enhance policies and outcomes of different medical areas including prophylaxis, treatment and health related objectives in colorectal cancer.

Familial and non-familial risk factors associated with colorectal cancer survival in young and middle-aged patients

BACKGROUND

Survival following colorectal cancer (CRC) survival may be influenced by a number of factors including family history, individual medical history, and comorbidities. The impact of these factors may vary based on the patient's age.

METHODS

The study cohort consisted of individuals born in Western Australia between 1945 and 1996, who had been diagnosed with CRC prior to 2015 (n = 3220). Hospital, cancer, and mortality data were extracted for each patient from state health records and were used to identify potential risk factors associated with CRC survival. Family linkage data, in combination with cancer registry data, were used to identify first-degree family members with a history of CRC. The association between survival following CRC diagnosis and identified risk factors was examined using Cox proportional hazard models.

RESULTS

Age and sex were not significantly associated with survival in young patients. However, in middle-aged patients increasing age (HR 1.03, 95% CI 1.01-1.05, p = 0.003) and being male (HR 0.72, 95% CI 0.60-0.87, p < 0.001) were associated with reduced survival. Being diagnosed with polyps and having a colonoscopy prior to CRC diagnosis were associated with improved survival in both young and middle-aged patients, while a history of non-CRC and liver disease was associated with reduced survival. In middle-aged patients, having diabetes-related hospital admissions (HR 1.53, 95% CI 1.15-2.03, p = 0.004) was associated with reduced survival.

CONCLUSIONS

In both young and middle-aged patients with CRC, factors associated with early screening and detection were associated with increased CRC survival while a history of liver disease and non-CRC was associated with decreased CRC survival.

Survival Rate of Colorectal Cancer in Iran: A Systematic Review and Meta-Analysis

Background: Different studies have been conducted to estimate the survival rate of colorectal cancer in Iran but there is no overall estimate of the survival rate. The aim of this study was to calculate the pooled 1, 3, and 5-year survival rate of the patients with colorectal cancer in Iran. Methods: To retrieve relevant studies, we conducted a systematic search in Iranian databases, including Iran Medex, Magiran, SID, and international databases such as Medlin/PubMed, Scopus, and Google scholar using “Colorectal Neoplasms” and “Survival Rate” as keywords up to December 1st, 2017. We used random effect model to estimate pooled 1, 3, and 5-year survival rates of the patients with colorectal cancer in Iran. To assess the heterogeneity, we used Chi-squared test at the 5 % significance level (p <0.05) and I2 Index. We used meta-regression and subgroup analysis to find a potential source of heterogeneity. Results: After a systematic search, 196 articles were found, of the 38 studies met the eligibility criteria and are included in our meta-analysis. The pooled 1, 3, and 5-year survival rates in patient with colorectal cancer were 0.84 (95% CI: 0.81-0.87), 0.64 (95%CI: 0.59-0.70), and 0.54 (95%CI: 0.49-0.58) respectively. The 5-year survival rate in the subgroup of women was 0.5 (0.44-0.56) and in male subgroup was 0.44 (0.40-0.48). In a subgroup of the tumor site, the 5-year survival rate in colon cancer was 0.6 (0.49-0.75) and rectum cancer was 0.54 (0.36-0.69). In multivariable models, there was a significant association between years of study and 5-year survival rate as a source of heterogeneity (β = 18.9, P=0.01). Conclusion: According to the results of this study, women had a better survival rate than men, and according to the tumor site, the 5-year survival rate in colon cancer was better than the rectum cancer.

Mixture cure model for estimating short-term and long-term colorectal cancer survival

AIM

We used mixture cure mode to separately investigate the risk factors for long-term and short-term survival of colorectal cancer patients.

BACKGROUND

Colorectal cancer (CRC) is the second most common cancer worldwide. In cancer studies, patients' survival is the most important indicator of patients' status. Classical methods in analyzing the survival data usually apply Cox proportional hazard regression.

METHODS

The study was performed on 1121 patients diagnosed with colorectal cancer. Mixture cure model with Weibull distribution and logit link function was fitted to data.

RESULTS

Odds of long-term survival for rectum cancer patients were lower than for colon cancer patients (OR=0.29(0.09, 0.9)). Also, patients with the advanced stage of the disease had lower odds of long-term survival compared to early-stage patients (OR=0.24(0.06, 0.86)).In the short-term, the hazard of death for people with normal BMI was lower than the underweight group (HR=0.4(0.21, 0.76)). The short-term hazard of death for rectum cancer was about half of the short-term hazard for colon cancer (HR=0.49(0.29, 0.81)). Further, people with moderately (HR=2.11(1.26, 3.55)) and poorly (HR=4.04(2.03, 8.03)) differentiated tumor grade had a higher short-term hazard of death compared to people with well-differentiated grade.

CONCLUSION

Predictive variables of colorectal cancer survival showed different effects in short- and long -terms. Site topography was a prognosis for both long-term and short-term survival; BMI and tumor grade were short-term predictors of survival while stage was a long-term predictor of survival.

A Spatial Survival Model in Presence of Competing Risks for Iranian Gastrointestinal Cancer Patients

Background:

Gastrointestinal cancer is one of the common causes of death from cancer in Iran. Survival analysis is usually used to detect prognostic factors of time to death from gastrointestinal cancers. The use of ordinary survival models, in the presence of competing risks and/or when data is collected within geographic areas, may lead to distorting the results. Therefore, the aim of this study is to use the spatial survival models in the presence of competing risks to assess the risk factors affecting the survival time of gastrointestinal cancer patients.

Methods:

The data in this study was collected from 602 patients who were diagnosed with gastrointestinal cancer in Golestan and Mazandaran provinces registered in Iran’s National Institute of Health Research from 2002 through 2007 and were followed up to July 2017. The data was analyzed using the cause-specific hazard frailty model with multivariate conditional autoregressive distribution for frailties in the presence of competing risks (death from gastrointestinal cancer, heart disease, and other causes) via OpenBUGS software.

Results:

The hazard of death from gastrointestinal cancer in men patients, patients who lived in rural areas, patients whose relatives did not have a history of cancer, patients who did not undergo surgery, and patients with gastric cancer was significantly higher than others. Based on the deviance information criterion (DIC), frailty models and spatial frailty models seemed better than no-frailty model and non-spatial frailty model, respectively.

Conclusions:

This study showed that the use of the spatial frailty term in the model helps better fit the model. Also, the spatial pattern in the figures suggests the necessity of presence of some still missing, spatially varying covariates relevant for time to death from gastrointestinal cancer, heart disease, or other causes.

Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran

OBJECTIVES

Colorectal cancer (CRC) patients are considered to have been cured when the mortality rate of individuals with the disease returns to the same level as expected in the general population. This study aimed to assess the impact of various risk factors on the cure fraction of CRC patients using a real dataset of Iranian CRC patients with a non-mixture non-parametric cure model.

METHODS

This study was conducted on the medical records of 512 patients who were definitively diagnosed with CRC at Taleghani Hospital, Tehran, Iran from 2001 to 2007. A non-mixture non-parametric cure rate model was applied to the data after using stepwise selection to identify the risk factors of CRC.

RESULTS

For non-cured cases, the mean survival time was 1,243.83 days (95% confidence interval [CI], 1,174.65 to 1,313.00) and the median survival time was 1,493.00 days (95% CI, 1,398.67 to 1,587.33). The 1- and 3-year survival rates were 92.9% (95% CI, 91.0 to 95.0) and 73.4% (95% CI, 68.0 to 79.0), respectively. Pathologic stage T1 of the primary tumor (estimate=0.58; p=0.013), a poorly differentiated tumor (estimate=1.17; p<0.001), a body mass index (BMI) between 18.6 and 24.9 kg/m² (estimate=−0.60; p=0.04), and a BMI between 25.0 and 29.9 kg/m² (estimate=−1.43; p<0.001) had significant impacts on the cure fraction of CRC in the multivariate analysis. The proportion of cured patients was 64.1% (95% CI, 56.7 to 72.4).

CONCLUSIONS

This study found that the pathologic stage of the primary tumor, tumor grade, and BMI were potential risk factors that had an impact on the cure fraction. A non-mixture non-parametric cure rate model provides a flexible framework for accurately determining the impact of risk factors on the long-term survival of patients with CRC.

Tackling socioeconomic inequalities and non-communicable diseases in low-income and middle-income countries under the Sustainable Development agenda

Five Sustainable Development Goals (SDGs) set targets that relate to the reduction of health inequalities nationally and worldwide. These targets are poverty reduction, health and wellbeing for all, equitable education, gender equality, and reduction of inequalities within and between countries. The interaction between inequalities and health is complex: better economic and educational outcomes for households enhance health, low socioeconomic status leads to chronic ill health, and non-communicable diseases (NCDs) reduce income status of households. NCDs account for most causes of early death and disability worldwide, so it is alarming that strong scientific evidence suggests an increase in the clustering of non-communicable conditions with low socioeconomic status in low-income and middle-income countries since 2000, as previously seen in high-income settings. These conditions include tobacco use, obesity, hypertension, cancer, and diabetes. Strong evidence from 283 studies overwhelmingly supports a positive association between low-income, low socioeconomic status, or low educational status and NCDs. The associations have been differentiated by sex in only four studies. Health is a key driver in the SDGs, and reduction of health inequalities and NCDs should become key in the promotion of the overall SDG agenda. A sustained reduction of general inequalities in income status, education, and gender within and between countries would enhance worldwide equality in health. To end poverty through elimination of its causes, NCD programmes should be included in the development agenda. National programmes should mitigate social and health shocks to protect the poor from events that worsen their frail socioeconomic condition and health status. Programmes related to universal health coverage of NCDs should specifically target susceptible populations, such as elderly people, who are most at risk. Growing inequalities in access to resources for prevention and treatment need to be addressed through improved international regulations across jurisdictions that eliminate the legal and practical barriers in the implementation of non-communicable disease control.

Lifestyle after Colorectal Cancer Diagnosis in Relation to Survival and Recurrence: A Review of the Literature

PURPOSE OF REVIEW

This review summarizes the evidence regarding diet, physical activity, smoking, and body composition after colorectal cancer (CRC) diagnosis in relation to all-cause and CRC-specific mortality and disease recurrence and gives suggestions for future research directions.

RECENT FINDINGS

Overall, this review suggests that some, albeit not all, of the well-known modifiable risk factors for cancer incidence might also be associated with CRC survival. CRC prognosis appears to be worse with increased physical inactivity, smoking, or being underweight after CRC diagnosis. Emerging evidence suggests that diets associated with a positive energy balance, e.g., high consumption of sugar-sweetened beverages, may negatively impact survival in CRC survivors. In contrast, there is currently little evidence to support the recommendation to limit red and processed meat or alcohol intake after CRC diagnosis. Whether being overweight and obese after CRC diagnosis improves or worsens CRC prognosis remains controversial and may depend on the measure used to assess body fatness.

SUMMARY

Further research on post-diagnosis lifestyle patterns is needed to understand the multifactorial influence on CRC prognosis. Disease recurrence and the development of comorbidities should be included as key outcomes in future studies and lifestyle should preferably be repeatedly measured.