(1) Background: Fecal occult blood test (FOBT) is the modality of choice in most countries for colorectal cancer (CRC) screening. We aimed to investigate the risk factors for CRC among patients with a positive FOBT in real life. (2) Methods: This was a retrospective study that included patients who tested positive for FOBT. Data regarding the comorbidities and laboratories were collected and compared between CRC and non-CRC groups. (3) Results: Positive FOBT was found among 45,500 (5.36%) subjects and CRC was found in 1502 (3.3%). CRC patients were older, age 62.7 ± 7.15 years compared with 59.33 ± 7.3 years (p < 0.001), and had significantly higher rates of hypertension (48.4% vs. 44.7%, p = 0.002), iron-deficiency anemia (20.6% vs. 16.4, p < 0.001), family history of CRC (7.3% vs. 5.1%, p < 0.001), and previous CRC (6.5% vs. 0.3%, p < 0.001). Lower levels of hemoglobin, iron, and ferritin were found in the CRC group. Age, family history of CRC, and previous CRC were found to be significant risk factors for diagnosis of CRC after positive FOBT with OR of 1.057, 1.4, and 15.9, respectively. (4) Conclusions: Iron-deficiency anemia, family history of CRC, previous colorectal cancer, and low hemoglobin, iron, and ferritin levels should direct physicians to give high priority to colonoscopy scheduling.
Keywords: colorectal cancer; fecal testing; risk factor; screening.