Clinical and epidemiological characteristics of colorectal cancer patients in a hospital-based series from Iran, 2009-2019.

BACKGROUND: Cancer remains a leading cause of mortality worldwide. Investigating the prevalence of its risk factors is essential for improving our understanding and clinical management of the disease. Cancers of the gastrointestinal tract are among the most common and lethal malignancies, frequently diagnosed at advanced stages when therapeutic options are limited. This study aimed to determine the hospital-based proportion and clinicopathological features of colorectal cancer (CRC) among patients presenting to a gastroenterology clinic. METHODS: This retrospective, hospital-based cross-sectional study reviewed all medical records of patients who underwent endoscopic and colonoscopic evaluations at the Gastroenterology Clinic between 2009 and 2019 using a total census approach. Patients were included if they had a histopathologically confirmed CRC diagnosis and complete records for target demographic and clinical variables. Patients with incomplete data, non-colorectal gastrointestinal (GI) malignancies, diagnoses outside the study period, or residency outside the province were excluded. RESULTS: Among 6223 total endoscopic and colonoscopic examinations performed over the 10 years, 34 CRC cases were identified, representing a hospital-based proportion of 0.55%. The mean age of affected patients was 57.2 ± 15.5 years (range: 25-88 years). The 55-69 age group was the most frequently represented (32.4%), while patients under 40 years accounted for 17.6% of cases. Males comprised 47.1% of cases and females 52.9%, with 85.3% of patients residing in urban areas. The most common presenting symptom was rectal bleeding/melena (44.1%), followed by abdominal pain (32.4%) and hematochezia (17.6%). Anatomically, tumors were located in the rectum (32.4%), sigmoid colon (29.4%), descending colon (17.6%), ascending colon (11.8%), and transverse colon (8.8%). All cases were histologically confirmed adenocarcinomas, categorized into poorly differentiated (38.2%), moderately differentiated (44.1%), and well-differentiated (17.6%) subtypes. A positive family history of CRC was reported in 23.5% of patients, whereas 73.5% had no documented specific risk factors. CONCLUSION: Colorectal cancer accounted for a hospital-based proportion of 0.55% among patients undergoing endoscopic evaluation at our center. While these clinical and pathological patterns provide valuable descriptive data for our clinic, they reflect a single-center hospital sample and cannot be generalized to population-level prevalence. Targeted hospital screening initiatives and close clinical follow-up for high-risk patients are recommended, alongside larger multi-center studies.