Immunomarker Studies of Fine-Needle Cytopuncture Cell Blocks for Tumor Response Prediction After Preoperative Chemotherapy and Prognosis in Operable Nonmetastatic Primary Breast Carcinoma

:  Neo-adjuvant chemotherapy of breast cancer provides an opportunity to evaluate predictive factors at initial tumor biopsy. We evaluated these factors on cell blocks obtained by diagnostic fine-needle cytopuncture (FNC), with respect to tumor regression and outcome. A prospective study (1996–2003, median follow-up 82 months) involved 163 patients with breast carcinoma (T2 ≥3 cm, T3, T4 noninflammatory) diagnosed by means of FNC. Malignancy, cytologic grade, and the presence of lymphocytes were determined on cytologic smears. Ki67, estrogen receptor (ER), progesterone receptor (PgR), HER2, and p53 expression was assessed on cell blocks by means of immunohistochemistry. All the patients received anthracycline-based chemotherapy. A combined clinical and pathologic tumor regression score was calculated. Twelve cases (7.5%) showed a complete regression, 72 cases (44%) a partial regression and 79 cases (48.5%) no regression. Factors predictive of regression were high grade, presence of lymphocytes, pN0, high Ki67 expression, hormone receptor negativity, and the “triple negative” phenotype. In univariate analysis 5-year metastasis-free survival rate (MFS) correlated with cytologic grade, pN, ER, and p53 status, while overall survival (OS) correlated with cytologic grade, type of surgery, pN, and ER status. In multivariate analysis, MFS was significantly influenced by the regression score, Ki67, age, ER status, pN, HER2, and initial tumor size. Except for age, the same parameters correlated with OS. FNC with the cell block technique is a rapid, minimally invasive, reliable, and inexpensive method for analyzing predictive biomarkers, and may thus be useful in the management of breast cancer patients requiring neo-adjuvant chemotherapy.