Amal Saki Malehi - Department of Biostatistics and Epidemiology, Faculty of Health, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Maedeh Raeiszadeh - Department of Biostatistics and Epidemiology, Faculty of Health, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Shima Younespour - National Institute for Health Research, Tehran University of Medical Sciences, Tehran, Iran
Mohammad Seghatoleslami - Environmental and Petroleum Pollutants Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Mehran Hosseinzadeh - Thalassemia and Hemoglobinopathy Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Elham Maraghi - Department of Biostatistics and Epidemiology, Faculty of Health, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran

Background: Breast cancer remains the most prevalent neoplasm in women, with more than ۴۵۰ ۰۰۰ deaths each year, worldwide. In cancer researches, several factors such as serum tumor markers have an important role in screening, treatment, and recurrence of the disease. Carcinoembryonic antigen (CEA) is one of the most widely used serum tumor markers in the clinical evaluation of patients with breast cancer. This study aimed to evaluate whether increasing serum CEA levels is an indicator of breast cancer patient’s survival or not.Materials and Methods: This retrospective study was done at Hematology Department of Shafa Hospital of Ahvaz, southwest of Iran. Only those patients who had mastectomy during ۲۰۰۶-۲۰۱۴ and regularly referred to the hospital were included. The joint survival longitudinal model was applied to analyze the data. JM package in R software was used for joint modeling analysis.Results: The five-year survival rate was ۷۳.۰%. Age and follow-up time were associated with CEA tumor marker values. Higher age is associated with higher CEA values over time (P = ۰.۰۱۵۶). There was a significant linear increasing trend in CEA values over time (P = ۰.۰۴۶۵). There was a significant difference between patients with and without nodal involvement (HR [۹۵% CI]: ۱.۸۸۰ [۱.۳۳۰-۵.۵۶۵]; P = ۰.۰۲۹۸). There was a positive correlation between CEA tumor marker levels and death (HR [۹۵% CI]: ۲.۷۷۰ [۱.۳۶۹-۵.۶۰۳]; P = ۰.۰۰۴۶).Conclusion: Higher age is associated with higher CEA values over time. The involvement of lymph nodes increases the hazard of death. Death is more likely to occur in patients with higher CEA tumor marker levels.

Breast cancer, Carcinoembryonic antigen (CEA), Joint modelling of longitudinal, Survival data