Pathological responses and long-term outcome analysis after neoadjuvant chemotheraphy in breast cancer patients from Kuwait over a period of 15 years

BACKGROUND AND OBJECTIVES: The attainment of pathological complete response (pCR) after neoadjuvant chemotherapy has been taken as a surrogate marker for disease-free survival and overall survival. This is however dependent on various other parameters such as stage, grade, and biologic markers. DESIGN AND SETTINGS: This is a retrospective study of 365 patients with histologically confirmed non-metastatic breast cancer patients treated with neoadjuvant chemotherapy at the Kuwait Cancer Control Centre between 1998 and 2009. PATIENTS AND METHODS: A total of 365 breast cancer patients who had received neoadjuvant chemotherapy from 1998-2009 were analyzed for the relationship of pCR with hormone status, Her2 status, histopathological subtype. Survival analysis was also conducted. RESULTS: Hormone receptor (HR) negative tumors had a higher pCR as against HR positive tumors, and the highest pCR in our analysis of pathological subtypes were seen in the HR+, Her2neu + and HR-, Her2neu + group. In our study, we could make out the paradoxes that well differentiated, and HR positive tumors had a better survival in spite of having lower pCR. The luminal A subtype also had a better overall survival than the triple negative subtype in spite of having lower pCR with neoadjuvant chemotherapy. CONCLUSION: Though the achievement of pCR retains its significance, it is more prognostic in HR negative tumors. The importance of HR receptor status, grade, and histopathological subtype in the long-term survival has been emphasized.