Clinical characteristics of colorectal cancer in Southern Iran, 2005

Background: Colorectal cancer is the second leading cause of cancer-related mortality and represents a major public health problem in developed countries. The objective of present investigation was to determine the epidemiologic aspects and clinical characteristics of colorectal cancer in Shiraz, southern Iran. Methods: This was a retrospective study carried out during 2000-2005, and comprised 491 subjects with pathologically documented colorectal cancer. They were registered in Fars Cancer Registry, affiliated to Shiraz University of Medical Sciences, southern Iran. A questionnaire including data on demographic information, histological types of cancer, site of primary cancer and metastasis were completed by trained interviewers. Results: Among 491 subjects, 57.2% were male and the most common age was 65-75 years. Patients under 45 years of age represented 22.8% of all colorectal cancer cases while 32% were over 65 years old. Those with a history of cancer in their first-degree relatives included 26.9% of the patients. Adenocarcinoma was the most common reported histological type of cancer (96.1%). Among all subjects, 60.7% suffered from abdominal pain, 28.4% abdominal distention and 28.0% rectal bleeding. Other symptoms included diarrhea/ constipation, nausea/vomiting, urogenital problems and mass sensation. The most common sites of metastasis were lung, brain and ovary. Conclusion: The incidence of colorectal cancer showed a remarkable increase in our region that might be due to changes in life style, decreased physical activity, heavy smoking habits, dietary changes and increased prevalence of obesity. Considering the elderly as the most vulnerable and the growing trend towards involvement of younger subjects, more studies and screening seems to be essential.