P3-14-20: Concomitant Taxane-Anthracyclin Regimen for Neoadjuvant Chemotherapy of Primary Breast Cancer: Experience from a Cohort of 223 Patients Treated in a Single Institution.

Abstract

Abstract Background: Neoadjuvant chemotherapy (NAC) may be an alternative to mastectomy for localized breast cancer ineligible for breast conservation. The optimal schedule (sequential versus concomitant) remains controversial. Based on encouraging results of a phase 2 study (Luporsi E. et al, ASCO 2000) a concomitant docetaxel (D) and epirubicin (E) neoadjuvant combination is applied in neoadjuvant setting in our institution since 2001 for HER2−negative patients (pts). The results of this combination are presented, with a particular focus on pathological complete response (pCR) and conservation rate. Methods: Between 2001 and 2010, 223 pts received NAC for a T2-T3 breast cancer initially ineligible for conservative surgery, but with hope of breast conservation in case of downstaging by pre-operative medical treatment. Six cycles of D (75mg/m2) and E (75mg/m2) were administered every 3 weeks before surgery, with prophylactic support of G-CSF in order to reduce the risk of febrile neutropenia and to maintain the dose-intensity of the NAC. All patients eligible for breast conservation after NAC underwent lumpectomy, the others were treated by mastectomy. In all cases, an axillary dissection was performed. After lumpectomy all patients received radiation therapy, after mastectomy RT was limited to high risk of loco-regional relapse. Patients with positive hormonal receptors (HR+) received hormonal therapy. Results were analyzed in term of breast conservation rate (BCR), pathologic response rate (pCR defined as no residual invasive tumour in breast and axilla, according to Sataloff's classification) and safety. Results: Mean age of patients was 49,6 years (range: 26–71). Median clinical tumor size was 40mm (range 20–110). Histological subtypes were:78,0 % ductal, 15,3 lobular, 1,8 % ductal/lobular and 4,9 % other types. SBR grading was: grade I: 14,3 %, grade II: 46,2 %, grade III: 33,2 % and 6,3 % unspecified. 77,3 % were HR+, 19,7 % of tumours were triple negative (HER2 unknown for 38 cases). A breast conservation was achievable for 73,5% of patients, the pCR rate was 20,6%. At a median follow up of 48 months, 31 pts relapsed: 9 pts (4%) experienced a local relapse, 5 regional and 28 distant recurrences occured. Additional data about safety and survival will be provided for the meeting. Conclusions: For HER2−negative tumours, 6 cycles of a concomitant taxane-anthracyclin pre-operative combination allowed a 20,6% pCR rate, slightly lower than obtained with 8 cycles of a sequential regimen in several published trials. However breast conservation rate was similar with a low risk of local recurrence. According to these results, concomitant cytotoxic combination is an acceptable option for neoadjuvant treatment of breast cancer. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-14-20.