• breast cancer;
  • invasive lobular carcinoma;
  • neo-adjuvant chemotherapy;
  • pathology;
  • tumor response

Abstract:  Neo-adjuvant chemotherapy is used for locally advanced breast cancer patients with significant variation in tumor response. Our objective is to determine the clinicopathologic effect of neo-adjuvant chemotherapy on invasive lobular carcinoma. A review of a single-institution data base of women diagnosed with breast cancer identified 30 patients from 1999 to 2009 with operable invasive lobular carcinoma who received neo-adjuvant chemotherapy. Patient demographics and clinicopathologic data were reviewed. Cases were reviewed by a single pathologist (NNE). Residual cancer burden class was determined for each case. Median patient age was 50 years (range 25–79). All tumors were hormone receptor positive and clinical stage II or III carcinomas. Most patients (53.3%) had combination anthracycline- and taxane-based chemotherapy. Therapy-related changes were noted within the tumor bed in 25 (83.3%) patients. Six (30%) of 20 patients with residual axillary disease had therapy-related nodal changes. There were 11 patients with moderate residual disease (class II) and 18 (60%) with extensive (class III); there were no complete pathologic responses (class 0). Only one patient (3.3%) converted from mastectomy to breast-conserving surgery. Four (13.3%) patients developed distant metastases; all had pleomorphic-type, clinical stage III tumors with residual cancer burden III classification and developed distant disease in the 2 years after surgery (range 0–26 months). Median follow-up time was 29.5 months (range 7–132). Patients with locally advanced pleomorphic-type lobular carcinoma appear to develop early post-treatment metastatic disease. Neo-adjuvant chemotherapy did not appear to have significant impact on the surgical treatment of patients with invasive lobular carcinoma.