Introduction
In patients suffering from breast cancer, adjuvant radiation, chemotherapy, or immunotherapy, which immediately follow the surgery as the first line therapy, greatly improve overall (OS) and disease-free survival (DFS). Various regimens of adjuvant therapy for these patients have been tested contingent upon the clinical staging. Inclusion of adjuvant immunotherapy is particularly promising.
Specific aim
The aim of this study was to assess efficacy of trastuzumab (Herceptin) - comprising adjuvant immunotherapy in terms of overall and disease-free survival as compared to other adjuvant therapies.
Patients
All patients were presented with the Patient Bill of Rights and have provided the Patient Informed Consent to participate in this study. Eligible patients include those with primary tumors initially staged at the clinical stages: I-T1c N0, II-T0-2, N0-1, or IIIA-T3 N1, or patients for whom neoadjuvant chemotherapy provides the possibility to remove surgically a tumor at the stage IIIA T0-3 N2.
Of 9,058 patients enrolled in the Breast Cancer Treatment Program between 2008 and 2015, 6,832 fulfilled the inclusion criteria.
Statistical Analysis
The effects of clinical and demographic factors on overall survival (OS) and disease-free survival (DFS) were assessed using Cox’s proportional hazards regression models. OS and DFS were evaluated with Kaplan-Meier calculations. The study was meeting the criteria for a controlled, open-access clinical trial.
Results
OS rates for years 1-7 were, respectively, 99.42%, 97.26%, 94.57%, 92.41%, 90.48%,
88.63%, and 88.23%; thus with the 5-year survival at 90.48%. The corresponding data for DFS were 96.17%, 84.07%, 77.26%, 72.57%, 68.59%, 65.04%, and 63.05%, respectively; thus with the 5-year DFS at 68.59%.
Adverse effects, with the exception of cardiac complications, occurred in 1194 (17%), while causing withdrawal of 421 (6%) patients. Most of other adverse events were related to hepatotoxicity 1755 (25%) and fatigue 681 (9.7%).
Conclusion
These results demonstrate the great benefits of inclusion of immunotherapy as the adjuvant component as currently the best overall therapeutic strategy for the patients suffering breast cancers. As this strategy greatly exceeds any other therapeutic options available for practicing oncologists at the present time, it definitely justifies allocation of all needed public resources, while assuring highest quality health service for the patients in Poland.
Adjuvant therapy in stage I carcinoma of the breast