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The epidemiology and clinical findings of colorectal cancer in Iran.

BACKGROUND
This study was performed to evaluate the prevalence, clinical features and management of patients with colorectal cancer (CRC) in Iran.


METHODS
All cases of CRC presented to a principal referral University hospital (SGH) for cancers in Teheran, Iran between June 20, 2000 and January 3, 2003 were retrospectively reviewed.


RESULTS
A total of 200 patients were included. 114 patients (57%) were male and 86 were female (43%). Age ranged from 13-90 years with a mean of 55.15 +/- 14.5. Among these patients, 16.5% were less than 40 years of age. The tumors were categorized according to their distribution as appendix (n=4), cecum ( n=7), right colon (n=1), hepatic flexure (n=2), transverse colon (n=19), splenic flexure (n=3), left colon (n=6), sigmoid ( n=16), rectum (n=117), rectosigmoid and rectal lesions (n=16), and colorectal lesions without known locations (n=9). Non-mucinous adenocarcinoma (AC) was the most common histological type (n=181, 90%), followed by mucinous AC (n=15), squamous cell carcinoma (n=1), carcinoid (n=1), melanoma (n=1) and signet ring carcinoma (n=1). The most common presenting symptom was rectal bleeding (n=68, 34.5%). Younger patients had a greater preponderance of mucinous AC (p=0.008) and generally underwent more extensive chemotherapy as seen with more usage of 5-Fluorouracil (p=0.05).


CONCLUSIONS
We have had few reports with reference to the epidemiology of CRC in Iran since 1977. The current data suggest a younger age distribution for CRC. We found no significant difference between age, gender and type of cancer with subsite distribution. Distal CRC was more prevalent. Among patients, 30.5% were diagnosed by screening studies.