Weekly paclitaxel improves pathologic complete remission in operable breast cancer when compared with paclitaxel once every 3 weeks.

PURPOSE: To determine the impact a change in schedule of paclitaxel administration from once every 3 weeks to frequent administration would have on the pathologic complete response (pCR) rate in the breast and lymph nodes for patients with invasive breast cancer treated with primary systemic chemotherapy (PST). PATIENTS AND METHODS: Patients with clinical stage I-IIIA breast cancer were randomly assigned to receive PST of paclitaxel doses administered either weekly (for a total of 12 doses of paclitaxel) or once every 3 weeks (four cycles), followed by four cycles of fluorouracil/doxorubicin/cyclophosphamide (FAC) in standard doses every 3 weeks. Two different doses of paclitaxel were used based on lymph node status defined by ultrasound and fine needle aspiration. Clinical response and extent of residual disease in the breast and lymph nodes was assessed after completion of all chemotherapy. RESULTS: A total of 258 patients were randomly assigned to receive doses of paclitaxel administered either weekly or once every 3 weeks, followed by FAC. Of these 258 patients, 110 patients had histologic lymph node involvement and 148 patients had clinical N0 disease. Weekly paclitaxel followed by FAC was administered to 127 patients and once-every-3-weeks paclitaxel followed by FAC was administered to 131 patients. Clinical response to treatment was similar between groups (P = .25). Patients receiving weekly paclitaxel had a higher pCR rate (28.2%) than patients treated with once-every-3-weeks paclitaxel (15.7%; P = .02), with improved breast conservation rates (P = .05). CONCLUSION: The change in schedule of paclitaxel from once every 3 weeks to a more frequent administration significantly improved the ability to eradicate invasive cancer in the breast and lymph nodes.

A detailed evaluation of cardiac toxicity: a phase II study of doxorubicin and one- or three-hour-infusion paclitaxel in patients with metastatic breast cancer.

PURPOSE: This Phase II study was designed to determine the efficacy and toxicity of combination doxorubicin and paclitaxel as front-line treatment for metastatic breast cancer. EXPERIMENTAL DESIGN: Eligible patients had no prior anthracycline or taxane therapy and normal cardiac function. They were treated with bolus doxorubicin 60 mg/m2, followed by paclitaxel 200 mg/m2, as either 1- or 3-h infusions for six to seven cycles. Single-agent paclitaxel was continued thereafter. Serial multiple gated acquisition scans were performed, and endomyocardial biopsies were performed for consenting patients. RESULTS: Eighty-two patients were enrolled with a median age of 53 years (range, 32-78 years). Of 79 evaluable patients, 58.2% had an objective response (3.8% complete response + 54.4% partial response), 34.2% had stable disease, and 7.6% had progressive disease. With median follow-up of 37.5 months, median time to progression was 7 months; median survival was 31 months. Multiple gated acquisition scans were performed in 82 of 82 patients at baseline, 75 of 82 patients at a total doxorubicin dose of 60-180 mg/m2, 62 of 68 patients at 200-300 mg/m2, 18 of 52 patients at 310-360 mg/m2, and 4 of 8 patients at 420 mg/m2. Median ejection fractions were 62.5, 60, 57.5, 52.5, and 32%, respectively. Fifteen of 82 (18.3%) patients had a decrease in ejection fraction > or = 15% to an absolute ejection fraction < or = 50%. Eight of these 15 patients (53%) developed clinical congestive heart failure: 4 of 8 (50%) who received a total doxorubicin dose of 420 mg/m2 versus 4 of 74 (5.4%) who received a dose < or = 360 mg/m2 (P = 0.002). CONCLUSIONS: When the doxorubicin dose exceeds 360 mg/m2, the combination of bolus doxorubicin and paclitaxel presents unacceptable cardiac risk.

Total RNA yield and microarray gene expression profiles from fine-needle aspiration biopsy and core-needle biopsy samples of breast carcinoma.

BACKGROUND: Gene expression profiling should be applicable to needle biopsy samples if microarray technology is to become practically useful for clinical research or management of breast carcinoma. This study compared gene expression profiles derived from fine-needle aspiration biopsy (FNAB) and from core needle biopsy (CBX). METHODS: Total RNA was extracted from single FNAB and CBX samples. Corresponding pairs of FNAB and CBX were analyzed for similarity of gene expression profiles using cDNA microarrays that contain 30721 human sequences. A subset of genes that distinguished CBX samples from FNAB samples was evaluated in a larger group of needle biopsy samples and in a published genomic database derived from 78 sporadic breast carcinomas with known clinical outcome. RESULTS: Sixty-eight patients with newly diagnosed breast carcinoma were included in the current study. Sixty-five patients underwent FNAB (17 had both FNAB and CBX) and 3 underwent CBX only. Extracted RNA was of suitable quality for hybridization in 46 (71%) FNABs and 15 (75%) CBXs. Total RNA yield in those samples was similar for single-pass FNAB (mean = 3.6 microg and median = 2.2 microg; n = 46) and CBX (mean = 2.8 microg and median = 2.0 microg; n = 15), with 1 microg or more of total RNA in all cases. Transcriptional profiling was performed successfully in all cases when it was attempted, in a total of 50 samples (38 FNABs and 12 CBXs), including matched FNAB and CBX samples from 10 patients. There were differences in gene expression profiles in 10 matched FNAB and CBX sample pairs. Genes that were expressed differently in CBX samples, compared with FNAB samples, were recognized as being predominantly from the endothelium, fibroblasts, myofibroblasts or smooth muscle, and histiocytes. Corresponding microscopic cell counts from FNABs demonstrated means of 80% tumor cells, 15% lymphocytes, and 5% stromal cells, whereas CBXs contained 50% tumor cells, 20% lymphocytes, and 30% stromal cells. Considering that CBXs are approximately six-fold richer in nonlymphoid stromal cells than FNABs and that CBXs differentially express a set of recognized stromal genes, the authors used these biopsies to define a transcriptional profile of breast carcinoma stroma. A set of 120 genes differentially expressed in CBXs was assessed independently in a published breast carcinoma genomic database to classify breast carcinomas based on stromal gene expression. Subgroups of tumors with low or high stromal signal were identified, but there was no correlation with the development of systemic metastases within 5 years. CONCLUSIONS: Both FNAB and CBX yield a similar quality and quantity of total RNA and are suitable for cDNA microarray analyses in approximately 70-75% of single-pass samples. Transcriptional profiles from FNAB and CBX of the same tumor generally are similar and are driven by the tumor cell population. The authors concluded that each technique has relative advantages. The FNABs provide transcriptional profiles that are a purer representation of the tumor cell population, whereas transcriptional profiles from CBXs include more representation from nonlymphoid stromal elements. Selection of the preferred needle biopsy sampling technique for genomic studies of breast carcinomas should depend on whether variable stromal gene expression is desirable in the samples.