Background Breast conserving surgery (BCS) has been established as a safe and effective alternative way of total (modified radical) mastectomy for achieving loco regional control of female invasive breast cancer. There are still obstacles on generalizing neoadjuvant chemotherapy as a primary treatment of breast cancer even on early tumors, including large presenting tumors size relative to breast size especially on small breast sizes. Introducing preoperative (neoadjuvant) chemotherapy (NACT) has been argued to increase rates of neoadjuvant chemotherapy because of decreasing the overall tumor’s size.

Aim of this study The aim of this work is to evaluate the efficacy of neoadjuvant chemotherapy on rates of breast conserving surgery on different molecular subgroups of breast cancer.

Patients and methods Record of total of 44 patients with pathologically proven invasive breast cancer, who received neoadjuvant chemotherapy were included in this study. Eligibility of patients for breast conserving surgery before and after receiving neoadjuvant chemotherapy was measured in different molecular subtypes of breast cancer.

Results Neoadjuvant chemotherapy increased eligibility for breast conserving surgery from 29% pre neoadjuvant chemotherapy to 77% post neoadjuvant chemotherapy. Highest rates of eligibility to neoadjuvant chemotherapy post neoadjuvant chemotherapy were achieved in HER-2 positive and Luminal A patients. Downstaging of the whole TNM disease stage decreased secondary to neoadjuvant chemotherapy in 89% of total study population. Luminal B patients showed the highest rates of downstaging. The average decrease in tumor size was 65.8% in response to neoadjuvant chemotherapy. HER-2 positive and triple negative patients showed the highest complete pathological response rates at 60.0% and 54.5% (p = 0.008).

Conclusion Neoadjuvant chemotherapy increased the rate of breast conserving surgery with variation in response depending on the molecular subtype of the tumor. Her2+ tumors were the most sensitive subtypes to neoadjuvant chemotherapy with the highest breast conserving surgery eligibility following neoadjuvant chemotherapy.

The authors have declared no competing interest.

This study did not receive any funding

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Ethics committees of Faculty of medicine for girls, Al-Azhar university, Cairo, Egypt gave ethical approval for this work

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All data produced in the present study are available upon reasonable request to the authors