Objective: To determine the Carcinoembryonic Antigen Levels among patients with epithelial carcinoma presenting at a tertiary care hospital.

Study Design: Prospective longitudinal study. Place and Duration of Study: Department of Medical Oncology, Jinnah Postgraduate Medical Centre, Karachi Pakistan, from May 2019 to May 2020.

Methodology: Two hundred six patients presenting with a confirmed diagnosis of epithelial carcinoma, aged more than 15 years and of either gender were enrolled in the study. The CEA levels in all the patients were measured using an ELISA kit. The CEA levels were classified as 0-3.0 ng/mL, 3.1-5.0 ng/mL, 5.1-10 ng/mL and >10ng/mL.

Results: The mean age of the cancer patients was estimated as 47.30±14.10 years. Most patients had rectum carcinoma 28(13.59%), followed by CA sigmoid 25(12.14%), respectively. The median CEA level was estimated as 5.80ng/mL ranging from 0.82 to 1000 ng/mL. About 76 patients had CEA level >10ng/mL (36.9%), 55 had CEA level 0-3.0 ng/mL (26.7%), 43 had CEA level 3.1-5.0ng/mL (20.9%), and 32 had CEA level 5.1-10.0ng/mL (15.5%). A statistically significant difference in proportions of CEA levels was found for histological type (p=0.001), type of cancer (p=0.001) and number of Mets (p=0.003).

Conclusion: Rectal cancer profoundly expressed carcinoembryonic antigen levels, followed by sigmoid, colon, and ovarian cancer. Moreover, there is a significant association among carcinoembryonic antigen levels, histology, type and metastasis of cancer.