[en] Objectives To evaluate the efficacy, cardiotoxicity profile and long-term benefits of neoadjuvant therapy in HER2-positive operable breast cancer patients. Methods A total of 142 patients diagnosed from 2005–2016 were included in the study. The treatment consisted of a sequential regimen of taxanes and anthracyclines plus trastuzumab. The clinical and pathologic responses were evaluated and correlated with clinical and biological factors. The cardiotoxicity profile and long-term benefits were analyzed. Results The median age was 49 years and 4%, 68% and 28% of patients had stage I, II and III breast cancer, respectively, while 10% had inflammatory breast cancer at diagnosis. Hormone receptor (HR) status was negative in 43%, and 62% had grade III breast cancer. The clinical complete response rate, was 49% and 63%, as assessed using ultrasound and MRI, respectively, and this allowed a high rate of conservative surgery (66%). The pathologic complete response (pCR) rate was 51%, and it was higher in HRnegative (64%) than in HR-positive (41%) patients. High HER2/FISH Ratio and high average HER2 copy number were correlated with higher pCR rates. Patients who achieved pCR had longer disease-free survival and a trend towards improved overall survival. A total of 2% of patients showed a 10% decrease in left ventricular ejection fraction to below 50% during treatment. All patients except one recovered after discontinuation of trastuzumab. Conclusion A sequential regimen of taxanes and anthracyclines plus trastuzumab was effective, with high pCR rates and long-term benefit, and a very good cardiotoxicity profile.

[gl] Obxectivos Avaliar a eficacia, cardiotoxicidade e beneficio a longo prazo do tratamento neoadxuvante nas pacientes con cancro de mama HER2 positivo en estadio precoz. Métodos Incluíronse 142 pacientes diagnosticadas entre os anos 2005-2016. O tratamento consistiu nunha secuencia de taxanos e antraciclinas con trastuzumab. Avaliouse a resposta clínica e patolóxica e correlacionouse con factores clínicos e biolóxicos. Analizouse a cardiotoxicidade e o seu beneficio na supervivencia. Resultados A mediana de idade foi 49 anos. O 6%, 68% e 28% das pacientes tiñan un estadio I, II e III respectivamente, mentres que o 10% presentaban un cancro inflamatorio ó diagnóstico. O receptor hormonal (RH) foi negativo no 43% e 62% dos tumores eran grao III. A taxa de resposta completa clínica medida por ecografía e resonancia foi do 49% e do 63% respectivamente e isto permitiu unha elevada taxa de cirurxía conservadora (66%). A taxa de resposta completa patolóxica (pCR) foi do 51% e esta resultou maior en pacientes con RH negativo (64%) que en RH positivo (41%). Elevados niveis do cociente HER2/CEN ou do número de copias do xene HER2 correlacionáronse cunha maior taxa de RCp. As pacientes que alcanzaron RCp tiveron unha mellor supervivencia libre de enfermidade e unha tendencia para mellorar a supervivencia global. O 2% das pacientes sufriu un descenso da fracción de exección do ventrículo esquerdo por baixo do 50% durante o tratamento. Todas as pacientes agás unha recuperaron a mesma tras suspender o trastuzumab. Conclusións A administración secuencial de taxanos e antraciclinas con trastuzumab foi efectiva, cunha elevada taxa de RCp, beneficio a longo prazo e un bo perfil de cardiotoxicidade