Influencing factors of the recurrence after neoadjuvant therapy in HER2-positive breast cancer.

person Serafin Morales Murillo Hospital Universitario Arnau de Vilanova, Geicam Spanish Breast Cancer Group, Lleida, Spain info_outline Serafin Morales Murillo, Ariadna Gasol Cud"S, Noemí Tuset Der-abrain, Alvaro Rodriguez, Ana Velasco Sanchez, Felip Vilardell, Douglas Sanchez Guzman, Carles Canosa Morales, Jordi Melé Olivé

Authors person Serafin Morales Murillo Hospital Universitario Arnau de Vilanova, Geicam Spanish Breast Cancer Group, Lleida, Spain info_outline Serafin Morales Murillo, Ariadna Gasol Cud"S, Noemí Tuset Der-abrain, Alvaro Rodriguez, Ana Velasco Sanchez, Felip Vilardell, Douglas Sanchez Guzman, Carles Canosa Morales, Jordi Melé Olivé Organizations Hospital Universitario Arnau de Vilanova, Geicam Spanish Breast Cancer Group, Lleida, Spain, Hospital Universitari Arnau de Vilanova de Lleida, Lleida, Spain, Hospital Universitari Arnau de Vilanova, Lleida, Spain, Hospital Arnau de Vilanova, Lérida, Spain Abstract Disclosures Research Funding No funding received Background: HER2-positive breast cancer is the more suitable subtype to perform a neoadjuvant therapy with chemotherapy and antiHER2 therapy because a high pathologic response and significance survival. However, despite this high percentage of pathological responses, there are still recurrences that can affect survival. Methods: We analyze a cohort of 287 HER-2 positive breast cancer treated with neoadjuvant chemotherapy and antiHER2 therapy according to current guidelines, to find the factors that could induce a recurrence. Results: Median age was of 56 (28-89), median tumor size of 37 mm (12-140), 145 (50%) had nodal involvement, estrogen receptor positive in 152 patients (53%) and median ki67 expression of 41% (3-95). HER2 expression by inmunohistochemistry was 2+ in 83 patients (29%) and 3+ in 204 (71%). A total of 50% complete pathological response (pCR) rate was detected and 54 (18,8%) relapsed. 17 patients with pCR (12%) and 37 patients without pCR (25%) had a recurrence (OR 4,31, p: 0,003). The factors that most influenced the relapse in the group of patients with pCR were: the initial size (greater than 5 cm) 30% of relapses, the initial axillary involvement (19%) and the cases with HER2 +3 expression and estrogen receptor negative (17%). In the group without pCR, the relapse was more frequent in patients with HER2 +2 expression and estrogen receptor negative (40%), HER2 +3 expression and estrogen receptor negative (43%), initial tumor size greater than 5 cm (38%) and axillary involvement (38%). Conclusions: Although pCR continues to be the most important factor to avoid relapse, there are other factors that must be considered as determinants of relapse despite achieving a pCR. Initial size greater than 5 cm is a poor prognostic factor despite reaching a pCR with up to 30% relapses, so other adjuvant interventions should be considered after initial neoadjuvant treatment.