Background Neoadjuvant chemotherapy is the treatment of choice in locally advanced breast carcinoma. Pertuzumab is approved in combination with trastuzumab and chemotherapy for the neoadjuvant treatment of patients with HER2 positive breast cancer.

Purpose To evaluate the complete pathological response rate (pRC) obtained after therapy in combination with pertuzumab in our hospital.

Material and methods Retrospective descriptive study of patients with confirmed diagnosis of HER2 positive breast cancer in treatment with pertuzumab in combination with trastuzumab and taxanes as neoadjuvant treatment (March 2017 to September 2018). Efficacy endpoint was the complete pathological response (pCR) that was related to efficacy and with a longer long-term survival. Adverse effects (AE) were collected for safety profile assessment.

Results Twenty-eight patients were analysed. The median age was 50 years (31–74). All patients had an initial ECOG 0–1. Sixty-three per cent had positive hormone receptors. The mean LVEF of patients at the beginning of the treatment with pertuzumab was 61%. Of the total, n=25 received chemotherapy treatment with AC at dense doses for four cycles prior to the taxane sequence, two patients received TCH and one patient received FEC. Dose reduction was performed in 18% of patients. Paclitaxel weekly for 12 cycles was the taxane level administered in combination with pertuzumab and trastuzumab in 93% of the cases. Radiotherapy and hormone therapy were used when necessary. In general terms, pertuzumab in combination with trastuzumab and taxanes was well tolerated, with AE grade 1–2 such as neurotoxicity, nausea and diarrhoea. No adverse events in grade 3–4 were recorded. Currently, 17 patients have been operated on: in 13 cases with pRC, in three patients there was a Miller and Payner grade 4 response and in one patient grade 3. The rest of the patients will have surgery soon.

Conclusion The data obtained so far are quite encouraging because of the good pRC rate obtained. However, we must treat them with caution due to the low number of patients who have received treatment up to now. But this treatment is going to improve the prognosis of the disease with a tolerable toxicity profile.

Reference and/or acknowledgements Lancet Oncol 2016;17:791–800.

No conflict of interest.