Objectives This is a observational study with the aim to evaluate predictive factors of response to NAT in patients with breast cancer.

Methods It is a retrospective study included 21 patients t who received neaoadjuvant chemotherapy between 2015 and 2019 at salah azaiez institute Tunisia., we collected, socociodemographics (age, gender, and marital status); tumor: localization, staging.

Results Our study included 21 patients who achieved breast pCR, between 2015 and 2019, 21 patients were included. The median age was 48 years (ranging 30–68). All patients had breast cancer and received neoadjuvant chemotherapy. Two patients were diabetic, 3 patients had high blood pressure and 2 had dyslipidemia. The majority of the tumor had a hign grad nuclear (14). The majority of molecular profile was tripe negative (6cases). The evaluation of the response based on imaging firstly and histological examination. Clinically all patient had a complete response. 17 patients underwent radical surgery and 4 conservative surgery. The evaluation of these patients showed that 16 of theme developed recurrence.We concluded that age, nuclear grad, histological type did not effected the response of chemotherapy but this results is insufficient because of the shortage of the serie.

Conclusions To date, no tumour biological factor is available for clinical use in the prediction of chemotherapy response in advanced breast cancer other than oestrogen receptor status, which predicts response to hormonal therapy