Pertuzumab (P) has been approved in neoadjuvant setting for HER2-positive early breast cancer patients (pts) in association with Trastuzumab (T) and chemotherapy. Diverse studies support this treatment. The pathologic complete response (pCR) showed achieve percentages from 45.8 % to 66.6% depending on chemotherapy combination.
This is a retrospective and multicentric study. We have collected all HER2-positive early breast cancer pts treated with P in neoadjuvant setting in our hospitals between 2015 and 2018. The effect of adding P on pCR was analyzed, as well as other predictive factors of response using logistic regression analyses. Kaplan Meier analysis has been used for survival analysis.
A total of 310 pts met the selection criteria. The median age was 51 years (22-88 years), 54,5% were premenopausal. 4 pts were stage I, 204 pts stage II, 101 pts were stage III. The majority of the patient received anthracyclines and taxanes with P and T regimen (77,1%), 16,5% received carboplatin-docetaxel-P-T combination and 6,5% received taxane-P-T. 307 pts were analysed for response. pCR was seen in 62,2 % of the pts, dividing by hormonal receptor (HR) status, pCR was 53,8% in HR-positive and 71,1% in HR-negative. Treatment was well tolerated with only 14.8 % G3-4 adverse events related to chemotherapy and 1.9% related to antiHER2 therapy. Different adjuvant treatments patterns were seen between hospitals. After a follow-up of 7,5 years, 43 pts (13,9%) had a distant relapse, 16 of them (37,2%) had achieved a previous pCR. 38,5% had CNS recurrence and 61,5% non-CNS recurrence. In multivariate analysis non-pCR pts have 3.9 relative risk of experience disease relapse event (p 0.0001; 1.84-8.88), and patients with stage III at diagnosis have 4.3 relative risk (p 0.00004; 2.15-8.75). Disease free-survival (DFS) rates at 7.5 years is 86.4 %. After separating between pCR outcomes, results were statistical significative (p < 0.0001) with DFS rates of 89.4% in pCR pts and 70.6% in non-pCR pts.
In our knowledge, this is the first real-world study that shows survival results for adding Pertuzumab in the neoadjuvant setting of HER2-positive breast cancer patients. Our results are consistent with those previously published.
The authors.
Has not received any funding.
A. Falcon Gonzalez: Non-Financial Interests, Personal, Speaker’s Bureau: Daiichi Sankyo, Roche, Novartis, Seagen, Pfizer, Eisai; Non-Financial Interests, Personal, Advisory Board: Medtronic, Pfizer, Seagen. J. Cruz Jurado: Financial Interests, Personal, Advisory Board: PharmaMar, Roche, Lilly, Pfizer, Novartis, Gilead, AstraZeneca, Daiichi, Seagen, GSK, Bayer; Financial Interests, Personal, Invited Speaker: PharmaMar, Roche, Lilly, Pfizer, Novartis, Eisai, Gilead, AstraZeneca, Daiichi, Seagen, Esteve, Roche. All other authors have declared no conflicts of interest.