ABSTRACT
This study was conducted to determine the prognostic effect hormone receptor [HR] status in early HER2 positive [HER2+] breast cancer patients, since it has not yet been established whether HR status can be used in the prognosis of patients with [HER2+] breast cancer. We obtained data from 299 patients with early HER2+ breast cancer who underwent surgery and received standard adjuvant chemotherapy, hormonal therapy and/or radiation between 2000 and 2002 at the Instituto Nacional de Enfermedaldes Neoplasticas, Peru. Clinical and pathological features were compared. Endpoints analyzed were disease free survival [DFS] and overall survival [OS]. Overall, 155 patients were HR-positive [HR+] and 144 were negative [HR-]. The two groups had similar characteristics except for histologic grade and extracapsular extension. With a median follow-up of 93 months, 5-year DFS was statistically different between the two groups: 65.0% for [HER2+/HR-] and 74.6% for the [HER2+/HR+] patients [P=.045]. OS at 5 years was not statistically different between the two groups with 75.5% for [HER2+/HR-] patients and 82.4% for the [HER2+/HR+] [P=.140]. Patients with [HER2+/HR-] breast cancers treated with surgery and standard adjuvant chemotherapy exhibited a statistically worse DFS compared to those with [HER2+/HR+] tumors. However, OS was similar in both groups