Bhumsuk Keam Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea , Seock-Ah Im Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea , Hee-Jun Kim Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea , Do-Youn Oh Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea , Jee Hyun Kim Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea , Se-Hoon Lee Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea , Eui Kyu Chie Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea , Wonshik Han Department of Surgery, Seoul National University College of Medicine, Seoul, Korea , Dong-Wan Kim Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea , Woo Kyung Moon Department of Radiology, Seoul National University College of Medicine, Seoul, Korea, , Tae-You Kim Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea , In Ae Park Department of Pathology, Seoul National University College of Medicine, Seoul, Korea , Dong-Young Noh Department of Surgery, Seoul National University College of Medicine, Seoul, Korea , Dae Seog Heo Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea , Sung Whan Ha Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea , Yung-Jue Bang Department of Internal Medicine and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea

Pathologic Examination and Immunohistochemistry

The pretreatment formalin-fixed, paraffin-embedded tissue blocks were used for immunohistochemistry. The pathological tumor stage assessed according to the criteria established by the 6th edition of AJCC cancer staging manual [18], the grade of the tumor according to the Scarff-Bloom-Richardson classification modified by Elston and Ellis [19]. The pathologic complete response (pCR) was defined as complete disappearance of invasive carcinoma in both breast and axillary lymph nodes after three cycles of chemotherapy. Residual ductal carcinoma in-situ was included in the pCR category.

ER, PR, c-erbB2, p53, bcl-2, and Ki-67 expressions were evaluated by the avidin-biotin complex immunohistochemical technique [20]. Tissue sections (4-μm thickness) from paraffin-embedded tissue blocks were cut, deparaffinized in xylene, rehydrated with graded ethanol, and immersed in Tris-buffered saline. After an antigen-retrieval process, primary antibodies were used as previously described [21]. The companies that supplied the primary antibodies and the dilution factors used were; ER (Dako Corporation, Carpinteria, CA, USA; 1:50), PR (Dako Corporation; 1:50), c-erbB2 (Novocastra Laboratories Ltd., New Castle-Upon-Tyne, U.K.; 1:200), p53 (Dako Corporation; 1:1200), bcl-2 (Dako Corporation; 1:50), and Ki-67 (Dako Corporation; 1:800). All primary antibodies were mouse monoclonal antibodies. Biotinylated anti-mouse antibody was used as secondary antibody and streptavidin horseradish peroxidase (Zymed laboratories, San Francisco, CA, USA) methods were used.

A cut-off value of 10% or more positively stained nuclei in ten high-power fields was used to define ER and PR positivity. C-erbB2 scores of 0, 1 and 2 were considered negative, and a score of 3 was considered positive [22]. In the current study, we did not have FISH information available on the majority of c-erbB2 positive patients. Ki-67 with ≤ 5% and p53 with <25% were considered as low expression. Triple negative subtype was defined as ER negative, PR negative, and c-erbB2 negative, regardless of the expression of EGFR or basal cytokeratins.

Statistical analysis

The significance of the difference in the response rate among different groups was calculated using the Chi-squared test and Fisher's exact test, where appropriate. Multivariate analyses were carried out using the Cox proportional hazard regression models. Relapse free survival (RFS) was determined as the interval between the initiation of neoadjuvant chemotherapy and the date when disease relapse or progression was first documented or the date of death from any cause. Overall survival (OS) was measured from the date of neoadjuvant chemotherapy initiation to the date of death. Survival comparisons between different groups were made using the log-rank tests. All values were two sided and statistical significance was defined as p < 0.05. SPSS version 12.0 software (SPSS, Inc., Chicago, IL, USA) was used for all statistical analyses.

Results

Patient Characteristics and efficacy

A total of 145 patients with a median age of 45 (range 25–69) were evaluated in this study. The clinical characteristics of the patients are summarized in Table 1. Most of the patients (84.1%) were clinical stage III at the time of initial diagnosis and eighteen patients (12.4%) had inflammatory breast cancers. The median tumor size was 5 cm which is relatively large for Asian woman who have small breast. The breast conserving surgery rate was 35.9%. The overall radiologic response rate (RR) was 68.9% including 7 complete response (4.8%) and 93 partial response (64.1%) (Table 2). All 7 radiologic complete responder showed pCR and four patients who showed radiologic residual lesion were turned out to pCR. Consequently, eleven patients (7.6%) achieved a pCR (Table 2).

Of 145 patients, 138 patients including patients with pCR received three more cycles of docetaxel and doxorubicin as planned adjuvant chemotherapy. Three patients who showed progressive disease and 4 patients who were unacceptable to docetaxel received different adjuvant chemotherapy using FAC (5-fluorouracil, doxorubicin, cyclophosphamide), AC (doxorubicin, cyclophosphamide) or CMF (cyclophosphamide, methotrexate, 5-fluorouracil) after curative surgery.

Median follow-up duration was 18.6 months. Estimated one and three year relapse free survival rates were 88.7% and 56.5%, respectively. Estimated one and three year overall survival rates were 97.5% and 71.6% respectively.