Background: In the treatment of locally advanced breast cancer, neoadjuvant chemotherapy approach has several objectives, including downsizing of irresectable tumor into operable disease.
     ILC is known to be less responsive to NAC. The reported proportions of ILC patients with a pathologic complete response (pCR) range from 1 to 3 % compared with 9 to 15 % for IDC patients
Objectives: To assess surgical decision after using neoadjuvant systemic therapy for locally advanced breast cancer patients with invasive ductal carcinoma (IDC) versus whom with invasive lobular carcinoma (ILC). To determine the impact of neoadjuvant chemotherapy (NAC) on different pathological types of locally advanced breast cancer cases.
Patients and Methods: This retrospective study included 50 patients in the period from Jun 2018 to Jun 2019 who were diagnosed as invasive ductal and invasive lobular Carcinoma classified into two equal groups. Each group had received neoadjuvant systemic therapy, at Department of Clinical Oncology and Nuclear Medicine, while surgical treatment, in form of modified radical mastectomy (MRM) or breast conserving surgery (BCS), was done between June 2019 and Mar 2020, at the Surgical Oncology Department in Al-Azhar university hospitals.
Results: In our study, we observed a reduction in T stage after NAC in 6 cases (24%) of ILC patients compared to clinical down staging in 20 cases (80%) of IDC group.
Conclusion: ILC patients were less responsive to neoadjuvant chemotherapy compared with IDC patients. BCS is less frequently achieved after NAC in patients with lobular histology compared with ductal histology.