Prognostic Factors in Patients with Breast Cancer Using Decision Tree

Background & objectives: Breast cancer is the second leading cause of cancer mortality for women, behind lung cancer in Iran. Given the high prevalence of breast cancer, it is crucial to determine the reproductive risk factors of breast cancer. Methods: A total of 139 female patients with breast cancer (the case group) and 279 healthy females (the control group) that were age-matched participated in the study from March 2018 to March 2019. Demographic and reproductive variables, including the number of pregnancies, breastfeeding, history of oral contraceptive use, abortion, age at first menstruation, and age at first childbirth, were all collected using a questionnaire. Conditional Logistic regression was utilized to calculate OR (CI: 95%), and the classification tree model was used to classify the patients. Results: The mean age of breast cancer patients was 50.8 ± 8.3. Positive first-degree family history, intake of oral contraceptive use, and delaying first pregnancy increased the chance of breast cancer. In contrast, breastfeeding and menstruation after age 14 played a protective role in the development of breast cancer. Conclusion: The findings of this study reveal that the age at first birth, use of oral contraceptives, first-degree family history, and lack of breastfeeding has a significant relationship with breast cancer. Thus, women who have experienced such factors are susceptible to breast cancer and must be prioritized for preventive treatments and screening.