A Systematic Review Over the Incidence of Colorectal Cancer in Iran

Report of 13-year survival of patients with colon and rectal cancers; lessons from Shiraz colorectal cancer surgery registry system of a level three medical center

Background

Colorectal cancer (CRC) is the second most common cancer in women and the third most common cancer in men worldwide, with an increasing trend in its incidence in Asian countries. In the present study, we aimed to describe the 13-year results of patients with CRC based on the Shiraz Colorectal Cancer Surgery (SCORCS) registry system in patients with a pathologically confirmed diagnosis of colon cancer (CC) and rectal cancer (RC) undergoing surgery.

Methods

Between 2007 and 2020, 811 patients, including 280 patients with CC and 531 patients with RC, registered in SCORCS, were included in the present study. The information collected for this study included demographic characteristics of the patients, primary clinical presentations, laboratory findings before surgery, radiologic and colonoscopy results, and surgical procedures. Death was confirmed by the physician as “CRC-related”. The data were analyzed by SPSS software version 21; life table and Kaplan-Meier curve were used for evaluating the overall survival, recurrence, and metastasis rates and Log-Rank test or Breslow test to check significant differences between the subgroups. The Cox proportional regression model was fitted to evaluate the prognostic factors of survival recurrence and metastasis.

Results

Laparoscopy was performed in 60% of patients (66% in RC and 51% in CC), laparotomy in 32% (27% in RC and 41% in CC), and 7% required conversion. The median time of follow-up was 29 months in all patients; 28 months in patients with RC, and 33 months in patients with CC; 1, 3, and 5 years’ survival rate was 90, 70, and 63% for all the patients, 89%, 67%, and 58% for RC and 90%, 74%, and 71% for CC, respectively (P = 0.009). The Cox regression analysis revealed tumor stages II, (P = 0.003, HR:2.45, 95% CI;1.34–4.49), III, (P ≤ 0.001, HR:3.46, 95% CI;1.88–6.36) and IV, (P ≤ 0.001, HR:6.28, 95% CI;2.73–14.42) in RC and stage IV, (P = 0.03, HR:9.33, 95% CI;1.1-76.37) in CC were the significant survival prognostic factors. The metastasis and recurrence of the tumors occurred earlier in patients with RC than CC (P = 0.001 and 0.03, respectively).

Conclusions

Long-term follow-up of patients with CRC in an Iranian population indicated the significance of screening for diagnosis of early stages and improved survival of the patients.

Participation Rate, Risk Factors, and Incidence of Colorectal Cancer in the Screening Program Among the Population Covered by the Health Centers in Arak, Iran

Background: Colorectal cancer (CRC) is among the most common and preventable cancers, the incidence and risk factors of which are different in various populations. Objectives: The present study aims at assessing incidence rate, risk factors, and symptoms of CRC among the populations aged 50 to 70 years old covered by the health centers in Arak, as well as evaluating participation rate in the CRC screening program. Methods: The present cross-sectional study was conducted from 2016 to 2019 among all of the individuals aged 50 to 70 years old, who were referred to rural, urban, and suburban health centers in Arak for CRC screening, and their data were recorded in the Sib system. The participation rate, risk factors (family and individual history of CRC, colorectal adenoma, and inflammatory bowel disease), symptoms (lower gastrointestinal bleeding, constipation with or without diarrhea, and weight loss), and crude incidence rate of CRC were calculated in the age range. Results: The mean (SD) age of the CRC was 59.72 (5.56) years. In addition, the individuals’ participation rate in the program was about 44.2%, which was more among women (55.5%) and villagers (93.7%). Most subjects complained of constipation in the last month and CRC family history. The CRC crude incidence rates were 35.93 (95% CI: 25.55 - 50.54), 40.96 (95% CI: 29.81 - 56.29), 43.76 (95% CI: 32.22 - 59.43), and 52.84 (95% CI: 40.05 - 69.71) per 100000 individuals during 2016, 2017, 2018, and 2019, respectively. Conclusions: The participation rate in the CRC screening program was low, and the trend of the cancer crude incidence rate increased among the populations aged 50 to 70 years. Finally, informing about the recognition of the risk factors and symptoms of cancer, as well as the timely referral for screening was considered essential.

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.

Spatio-temporal analysis of colorectal cancer using a geographic information system in the Iranian military community during the period 2007-2016

INTRODUCTION

Colorectal cancer (CRC) is one of the most prevalent cancers among Iranian people. The study of spatio-temporal distribution of disease has an important role in the design of disease prevention programmes. The purpose of the current study was to describe the spatio-temporal distribution of CRC in the Iranian military community as a sample of the Iranian population.

METHODS

In the current ecological study, all registered cancer cases in the Iranian military community during the period 2007-2016 were considered. To identify hotspots, Getis-Ord Gi statistics were used. All analyses were performed using ArcGIS 10.5 and Excel 2010.

RESULTS

The highest incidences of CRC in 2007-2008, 2009-2010 and 2011-2012 were recorded in Kermanshah province. The highest incidences of CRC in 2013-2014 were seen in Kermanshah, Ghilan, Tehran and North Khorasan. In 2007-2008 and 2009-2010, hotspots were detected in West Azarbayjan. In 2011-2012, hotspots were detected in Zanjan and Qazvin. In 2013-2014, a hotspot was detected in Qazvin. Finally, West Azerbaijan was the hotspot for CRC in 2015-2016.

CONCLUSIONS

The incidence of CRC in men was higher than in women. Also it appeared that North and North West Iran were risk areas for this disease, and so these areas should be considered in the design of disease prevention programme for this cancer type. Additionally, the determination of individual risk factors in the aforementioned geographical areas can play an important role in the prevention of this type of cancer.

Positive correlation between vitamin D receptor gene FokI polymorphism and colorectal cancer susceptibility in South-Khorasan of Iran

Colorectal cancer (CRC) is a global public health problem. Despite the major milestone in early diagnosis and treatment of colorectal cancer, the prevalence of CRC rates is still rising. The etiology of CRC is still unknown but we know CRC is influenced by both of environment and genetic factors. In this study, we aimed to elucidate the role of vitamin D receptor gene polymorphic regions; FokI and TaqI single nucleotide polymorphisms, in increasing the risk of colorectal cancer in Birjand population. One hundred patients with CRC and 100 healthy controls recruited to the study. Genotyping was performed by PCR-RFLP (restriction fragment length polymorphism) method technique for all individuals. There were statistically significant differences between ff genotype and f allele of FokI SNP in case and control groups. Our results manifested positive correlation between ff genotype and f allele of FokI SNP with colorectal cancer predisposition (P = 0.035, P = 0.0001 respectively) in South Khorasan population. The present study showed that FokI polymorphism but not TaqI polymorphism may contribute to CRC susceptibility. In addition, ff genotype of FokI polymorphism was associated with CRC risk.

Colorectal cancer incidence and clinicopathological features in northern Tunisia 2007–2009

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. The aim of this study was to determine CRC incidence and to describe clinicopathological features in north Tunisia for the period 2007–2009. The North Tunisia Cancer Registry was the source of data for the identification of patients. The age-standardized incidence rates (ASRs) were respectively 13.6 cases (7.5/100,000 for colon cancer and 6.2 for rectal cancer) and 11.1 cases (6.5/100,000 for colon cancer and 4.4 for rectal cancer) per 100,000 among male and female. The ASR varied widely by regions in northern Tunisia.  The most common site in colon cancer was the distal colon comparing to the proximal one (49.0 and 29.9% respectively). Adenocarcinoma was the most common histological type. CRC screening should be strengthened in Tunisia to achieve a reduction of CRC incidence and mortality.

Low Level of Microsatellite Instability Correlates with Poor Clinical Prognosis in Stage II Colorectal Cancer Patients

The influence of microsatellite instability (MSI) on the prognosis of colorectal cancer (CRC) requires more investigation. We assessed the role of MSI status in survival of individuals diagnosed with primary colorectal cancer. In this retrospective cross-sectional study the MSI status was determined in 158 formalin-fixed paraffin-embedded tumors and their matched normal tissues from patients who underwent curative surgery. Cox proportional hazard modeling was performed to assess the clinical prognostic significance. In this study we found that MSI-H tumors were predominantly located in the colon versus rectum (p = 0.03), associated with poorer differentiation (p = 0.003) and TNM stage II/III of tumors (p = 0.02). In CRC patients with stage II, MSI-L cases showed significantly poorer survival compared with patients who had MSI-H or MSS tumors (p = 0.04). This study indicates that MSI-L tumors correlate with poorer clinical outcome in patients with stage II tumors (p = 0.04) or in tumors located in the colon (p = 0.02). MSI-L characterizes a distinct subgroup of CRC patients who have a poorer outcome. This study suggests that MSI status in CRC, as a clinical prognostic marker, is dependent on other factors, such as tumor stage and location.