Frequency and Pattern of Premalignant and Malignant Lesions among Fecal Immunochemical Test Positive Patients

Colorectal cancer is a challenging clinical entity worldwide. Adenomatous polyps are considered precursors to cancer. Detection and confirmation of mucosal healing of ulcerative colitis require a colonoscopy. For early detection of polyps or ulcers, different screening investigations like colonoscopy, Fecal Immunochemistry Test, gFOBT, CT colonography, etc. are used. Though gold standard colonoscopy has both diagnostic and therapeutic roles, Fecal Immunochemistry Test can detect advanced adenoma or established cancer or mucosal status of Ulcerative colitis. The Fecal Immunochemistry Test is a less expensive technique for the early detection of colonic pathology and is suitable for our demographic. The aim of the study was to observe the frequency and pattern of premalignant and malignant lesions among Fecal Immunochemical Test (FIT) positive patients. This observational cross-sectional study was conducted from July 2019 to June 2020 among 105 Fecal Immunochemical Test (FIT) positive patients. The observational cross-sectional study was carried out in the Department of Colorectal Surgery, Bangabandhu Sheikh Mujib Medical University and some private hospitals, Bangladesh. FIT tests were done in ICDDR`B. Among 105 Fecal immunochemical test positive study patients, colonoscopy evaluations were done. Among these, 58 cases (55.2%) revealed different types of polyps. Pedunculated polyps 42(40.0%) were predominant, present in 42(40.0%) of patients. Other than polyps, there were ulcers 14(13.3%), malignant looking growth 3(2.9%), hemorrhoid 13(12.4%) and normal findings in 15(14.3%) cases. The age range was 40-70 years. The mean age was 51.73±7.97 years. Adenomatous polyps and malignancies were 47(44.7%) and 5(4.8%). Advanced adenomas were 11(10.4%) cases. Thirty six (62.1%) polyps were in the left colon. Patients with normal findings, diverticulosis and hemorrhoids had not undergone biopsy. Fecal immunochemical test (FIT) can predominantly detect adenomas, especially advanced adenoma and precursor lesions. The study finding showed that both non-neoplastic, neoplastic polyps and ulcers had occult bleeding. So, they became FIT positive. Though colonoscopy is the gold standard in the detection of polyps, ulcers, or malignant lesions, FIT can be a good supportive tool for screening.