Refining Risk Factors for Colorectal Cancer in Patients Presenting with Gastrointestinal Complaints: A Cross-Sectional Study

Colorectal cancer (CRC) is a colon or rectum gastrointestinal malignancy. The colon and rectum cancers usually merge due to their common characteristics (1). Colorectal cancer is the third most frequent malignancy and the fourth cause of death due to cancer (2). Colorectal cancer usually originates from the glandular epithelial cells of the large bowel. A series of genetic or epigenetic mutations cause the hyper-proliferation of specific epithelium cells, leading to benign adenomas, which may sometimes progress to carcinomas (3). The main risk factors for CRC include increasing age, positive family history, pre-cancerous conditions, insufficient physical activity, obesity, and alcohol consumption (1, 4). Inflammatory bowel disease (IBD) is also associated with a two-fold risk of affliction by CRC (3). Colorectal cancer may present with rectal bleeding, abdominal lump, abdominal pain, altered bowel habits, unexplained weight reduction, and iron deficiency anemia (5). However, these symptoms are not specific to CRC, and endoscopy remains the main method for diagnosing CRC (5, 6). Different factors should be considered to choose the best treatment method for CRC. Nevertheless, the most frequent therapeutic option is surgery (7). Despite the improvements in the treatment strategies, the survival rate during five years remains at 14% in patients with distant stages of CRC (4). Information on the epidemiological characteristics and factors associated with this malignancy among the Persian population is scarce.

Due to the significance of CRC and the uncertainty of its causes, we decided to conduct a study to determine the prevalence of CRC and its risk factors in patients referring to Shahid Rahimi and Shohada-ye Ashayer hospitals of Khorramabad from 2017 to 2020.

In this study, 600 patients with gastrointestinal disorders were included, of whom 303 cases (50.5%) were male, and 297 patients (49.5%) were female. The mean age of patients was 55.06 ± 20.62 years. Two-hundred and sixty-five patients (44.1%) were elderly. A total of 28 patients (13 females and 15 males) were diagnosed with CRC. Other data are listed in Table 1.

Of 15 men (2.5%) and 13 women (2.2%) had been diagnosed with CRC. There was no significant relationship between gender and CRC (P = 0.84) (Table 2). Regarding the age group, 5 out of 28 patients with CRC (0.9%) were young, 12 cases (2%) were middle-aged, and 11 cases (1.8 %) were elderly. There was no significant relationship between age and CRC (P = 0.13). Regarding a history of IBD, 24 patients (4%) had no history of IBD, and four cases (0.7%) reported a history of IBD. There was no considerable relationship between IBD and CRC (P = 0.522). Regarding family history, 26 patients (4.3%) had no family history of CRC, and two cases (0.3%) mentioned a history of CRC in their first-grade relatives. Family history and CRC had no significant link (P = 0.682). In terms of marital status, 23 patients (3.8%) were married, 1 case (0.2%) was single, 3 cases (0.5%) were widows/widowers, and 1 case (0.2%) was divorced. Marital status and CRC had a significant relationship (P = 0.049). In terms of educational levels, 19 patients (4.2%) had education less than 12th grade, 3 cases (0.7%) had a high school diploma, and three cases (0.7%) had a college or university degree. There was no significant link between educational level and CRC (P = 0.37). Regarding smoking history, 23 cases (3.8%) were non-smokers, and 5 cases (0.8%) were smokers. Smoking and CRC had no remarkable relationship (P = 0.815). Also, 25 patients (4.2%) had no history of drug abuse, and three cases (0.5%) were drug abusers. Drug abuse and CRC had no significant association (P = 0.99). Further information is listed in Table 2.

In the present study, 600 patients with gastrointestinal disorders were included. A total of 28 individuals (13 women and 15 men) had been diagnosed with CRC. However, there was no statistically significant relationship between CRC and gender. Gao et al., in a study on 313,350 new cases of CRC, found that more men were diagnosed with CRC (162,741 men versus 150,609 women). They reported that the age-adjusted incidence of CRC was higher in men than women (8). Also, de Kok et al. reported that the age-standardized incidence rate of CRC was 40.1 per 100,000 person-years in males and 29.4 per 100,000 person-years in females (9). Abotchie et al. showed that the incidence rate ratio for CRC between males and females was 1.38 (10). Overall, it has been suggested that the lifetime risk of CRC is similar in males and females; however, the incidence rate is higher in men due to a longer life expectancy in women (4). We found no statistically significant relationship between CRC and age. Inconsistent with our findings, it has been reported that the incidence rate of CRC increases rapidly with age (4). Siegel et al. found that 60% of CRC cases occurred in individuals aged ≥ 65 years (11). However, the proportion of cases diagnosed with CRC before the age of 50 years has increased in recent decades (12). In our study sample, 17 out of 28 patients with CRC were young and middle-aged, which may indicate that the age at diagnosis is lower in the Persian population than in other populations. In the present study, there was no considerable relationship between CRC and the history of IBD. The relationship between IBD and CRC has been described in several studies. Gillen et al. found an 18-fold rise in the risk of developing CRC in patients with Crohn's colitis and a 19-fold rise in patients with ulcerative colitis compared to the general population (13). However, Jess et al. reported that the overall risk of CRC among individuals with ulcerative colitis was similar to that of the general population (14). We found no remarkable relationship between CRC and a family history of CRC. In contrast to our study, Weigl et al. found a strong association between family history and CRC risk (15). Roos et al., in a meta-analysis, reported a relative risk of 1.92 for CRC in patients with 1 first-degree relative in case-control studies and 1.37 in cohort studies (16). Savijärvi et al. reported that colon cancer incidence was higher among individuals with high educational levels (17). However, the present study had no statistically significant association between CRC and educational levels. We found no significant relationship between CRC and smoking. In contrast to our study, Botteri et al., in a meta-analysis, concluded that cigarette smoking was considerably associated with CRC incidence (18). Also, Liang et al. reported a 17% higher risk of developing CRC in smokers than those who never smoked (19). There was no significant relationship between CRC and a history of drug use. However, Naghibzadeh-Tahami et al., in a case-control study, concluded that opioid use could increase CRC risk (20). Furthermore, Bidary et al. reported an increased risk of colon cancer in opium consumers compared to non-consumers (21). In the present study, 23 out of 28 patients with CRC were married. There was a significant relationship between CRC and marital status. Li et al. reported that 55.20% of CRC patients were married and had a survival advantage (22). The differences observed between our findings and previous studies' findings may reflect the presence of latent genetic disorders and unknown environmental risk factors among our population. This may indicate the need for designing screening programs according to the epidemiological features of this population. Currently, several screening programs have been recommended for CRC. Based on the U.S. Multi-Society Task Force on Colorectal Cancer, screening should be suggested to all average-risk people aged 45 to 49. If they have not begun screening before 50, they should be suggested to initiate screening at 50. A colonoscopy every 10 years or an annual fecal immunochemical test (FIT) are the first-line options for screening (23).