RESUMO
<p><b>OBJECTIVE</b>To investigate whether apollon immunoexpression in breast cancer tissues helps to predict pathological complete response (pCR) after neoadjuvant chemotherapy (NAC).</p><p><b>METHODS</b>The expressions of Apollon, Her-2, estrogen receptor (ER) and progesterone receptor (PR) were detected immunohistochemically in biopsy tissues from 124 breast cancer patients. The clinical responses to NAC were evaluated in line with the response evaluation criteria in solid tumors (RECIST). The pCR rate was analyzed for different types of breast cancer. The correlations between Apollon status with Her-2, ER, PR, lymph node status and tumor size were analyzed. Immunohistochemistry was used to compared the changes in Apollon expression in the breast cancer tissues before and after NAC.</p><p><b>RESULTS</b>The pCR rate was 18.5% (23/124) in these patients. Negative expressions of apollon, ER and PR were all associated with a higher pCR rate after NAC. Apollon was significantly correlated with Her-2, ER, PR and lymph node involvement. Chemotherapy significantly down-regulated apollon expression in the tumor cells.</p><p><b>CONCLUSION</b>A negative apollon expression might be a predictor of pCR in patients with breast cancer.</p>