Correlation of Serum CA242, CA724, and TPA Levels with Clinicopathological Features and Prognosis in Patients with Inflammatory Bowel Disease Complicated with Rectal Cancer

OBJECTIVE: To investigate the correlation of serum cancer antigen 242 (CA242), cancer antigen 72-4 (CA724), and tissue polypeptide antigen (TPA) levels with clinicopathological features and prognosis in patients with inflammatory bowel disease (IBD) complicated with rectal cancer. METHODS: The data of 120 patients with IBD were retrospectively analyzed. Patients were divided into the IBD group (without rectal cancer, n = 60) and the rectal cancer group (with rectal cancer, n = 60), and 60 healthy individuals receiving medical examination during the same period were selected as the healthy group. Serum CA242, CA724, and TPA levels of research subjects were measured by enzyme-linked immunosorbent assay (ELISA). Meanwhile, the clinical data of the patients were collected. The patients were followed up for 3 years and divided into the survival group and the dead group. The relationship between the levels of CA242, CA724, TPA, and prognosis was tested. RESULTS: Significant differences were found in the serum CA242, CA724, and TPA levels among three groups (P < 0.001). CA242 was related to tumor size, histological stage, growth mode, and TNM stage in patients with IBD and rectal cancer. CA724 was related to histological stage, growth mode, depth of tumor invasion (T stage), lymph node metastasis (N stage), distant metastasis (M stage), and TNM stage in patients with IBD and rectal cancer. TPA was related to histological stage, T stage, M stage, and TNM stage in patients with IBD and rectal cancer. Serum CA242, CA724, and TPA levels in the survival group were significantly lower than those in the dead group after 3 years (P < 0.001). As for the combined prediction of serum CA242, CA724, and TPA for patients' prognosis, the confidence interval was 0.000-1.000, AUC was 0.875, standard error was 0.093, and sensitivity was 0.750. CONCLUSION: Serum CA242, CA724, and TPA levels are closely related to the clinicopathological features such as location, stage, and metastasis of rectal cancer. The combined detection of serum CA242, CA724, and TPA levels has a significant correlation with the prognosis of patients with rectal cancer, which can be used in monitoring the disease progression.