Comparing three adjuvant chemotherapy regimes after modified radical mastectomy in breast cancer patients using log-logistic model

Introduction: Chemotherapy after surgery is one of the adjuvant therapy components in breast cancer patients. In the current study, Taxane-based and Anthracycline-based regimes were compared to Cyclophosphamide, Methotrexate and 5-Fluorouracil (CMF) chemotherapy after modified radical mastectomy (MRM) surgery in terms of disease-free survival (DFS). Materials and Methods: Sixty-two patients with confirmed breast cancer that underwent MRM surgery at no metastasis stage (M0) enrolled. These patients were received one of the three types of adjuvant chemotherapies that mentioned above and the relapse/metastasis in 8-year follow-up was recorded. In addition, some paraclinical and demographical factors were recorded and the efficacy of the different chemotherapy regimes was compared using log-logistic survival model. Results: The mean age (SD) of patients was 49 (1.31). More than 40% of patients had tumors with grade 3. The median time of follow-up was 20.0 months and the rate of 5-year DFS was 48%. Survival analysis indicated that type of chemotherapy (OR(Taxane/CMF) =3.676 OR (Anthracycline/CMF) =3.185), histological grade (OR=2.528), tumor size (OR=5.598) and number of lymph nodes (OR=1.112) affect the DFS. Conclusion: The results of the current study indicated that the efficacy of Taxane-based and Anthracycline-based is more than CMF. This study also showed that early detection of tumor was an important factor for a successful treatment in terms of DFS, and so, it declares the roll of screening and public education.