Lack of association between amplification of her-2 and response to preoperative taxanes in patients with breast carcinoma

Background: The objective of the current study was to determine whether her-2 amplification was associated with a pathologic response to preoperative chemotherapy with taxanes in patients with early-stage breast carcinoma.

Methods: The authors evaluated 71 patients treated for AJCC Stage II and III breast carcinoma with preoperative taxanes whose tissue specimens were still available. Fifty-seven patients (80%) had received paclitaxel and 14 (20%) had received docetaxel (4 cycles of either drug). Amplification of the her-2 gene was determined using fluorescence in situ hybridization.

Results: The median patient age was 49 years (range, 21-70 years). Forty-eight patients (68%) had Stage II breast carcinoma and 23 (32%) had Stage III disease. her-2 gene amplification was detected in 19 tumor specimens (28%). Hormone receptors (estrogen and/or progesterone) were detected in 11 her-2-positive tumor specimens (58%) and in 31 her-2-negative tumor specimens (85%). Eight pathologic complete responses (pCR; breast and axillary lymph nodes) occurred, 3 (16%) in patients with her-2-positive tumor specimens and five (10%) in patients with her-2-negative tumor specimens (P = 0.68). Twelve patients achieved pCR in the breast, 5 (26%) in patients with her-2-positive tumors and 7 (15%) in patients with her-2-negative tumors (P = 0.3). At a median follow-up of 61 months, none of the patients with a pCR developed recurrent disease, regardless of their her-2 status. The progression-free and overall survival rates were similar in both HER-2-positive and her-2-negative groups (P = 0.45 and P = 0.14, respectively).

Conclusions: her-2 gene amplification was not found to be predictive of a pathologic response to preoperative taxanes in patients with early-stage breast carcinoma.