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The fecal occult blood test (FOBT) is a diagnostic modality for detecting microscopic blood in stool, primarily employed in colorectal cancer (CRC) screening. CRC ranks among the most prevalent malignancies in men and women worldwide, and early detection significantly reduces associated morbidity and mortality.[1] The fecal immunochemical test (FIT), a newer method, utilizes antibodies to detect human hemoglobin and has largely supplanted FOBT due to superior specificity, enhanced sensitivity, and lower cost.[2] Blood entering the upper gastrointestinal tract undergoes complete digestion of the globin portion of hemoglobin by proteolytic enzymes. Heme is converted by bacterial action into porphyrins. Hemoglobin reaching the lower intestine is largely undigested. In healthy individuals, gastrointestinal blood loss typically ranges from 0.5 to 1.5 mL per day, below the detection threshold of standard FOBTs.[3] Detection methods are based on the identification of hemoglobin or its degradation products.[4] Fecal blood may also be identified via macroscopic examination for erythrocytes or hematin crystals or spectroscopic analysis of hemoglobin and its derivatives.[5]