Prospective Validation of a 21-Gene Expression Assay in Breast Cancer

Prior studies with the use of a prospective–retrospective design including archival tumor samples have shown that gene-expression assays provide clinically useful prognostic information. However, a prospectively conducted study in a uniformly treated population provides the highest level of evidence supporting the clinical validity and usefulness of a biomarker

Treatment with tamoxifen affects the histology of the rat mammary gland

<p><b>Copyright information:</b></p><p>Taken from "Transforming growth factors-β are not good biomarkers of chemopreventive efficacy in a preclinical breast cancer model system"</p><p>Breast Cancer Research 2000;3(1):66-75.</p><p>Published online 8 Nov 2000</p><p>PMCID:PMC13902.</p><p>Copyright © 2000 BioMed Central Ltd on behalf of the copyright holder</p> Representative hematoxylin and eosin stained sections of the first thoracic gland of 15-week-old rats that had undergone the following treatments: No treatment; moderate numbers of mammary gland lobules are present containing primary, secondary and tertiary ductules, as well as developing alveoli. Initiation with NMU at 8 weeks of age; no significant histologic differences are noted in mammary gland development from that in untreated control animals. Initiation with NMU at 8 weeks, followed by treatment with tamoxifen from 9 to 15 weeks of age; scant numbers of atrophic primary and secondary mammary gland ductules are noted, with no alveolar bud development evident. (a, c, e) Shot at 100×; and (b, d, f) shot at 400× original magnification

Selection of local therapy after neoadjuvant chemotherapy in patients with stage IIIA,B breast cancer

Background: Stage IIIA,B breast cancer is commonly treated with neoadjuvant chemotherapy because of high objective response rates and improved operability. Criteria for subsequent selection of local therapy—mastectomy, radiotherapy, or both—are not well defined. We adopted a policy of selective local therapy based on rebiopsy of the breast and clinical axillary lymph node status at the time of best response to chemotherapy. Methods: Between 1980 and 1993, 126 patients with stage IIIA,B breast cancer were treated with neoadjuvant chemotherapy and definitive local therapy. The long-term incidence of locoregional failure (in-breast, chest wall, axilla, supraclavicular, neck), relapse-free survival, and overall survival was determined. Results: The overall clinical objective response rate to chemotherapy was 95.2%. Eighty-three patients underwent mastectomy, with negative margins achieved in 91.6%. Forty-two patients had breast preservation; the overall in-breast recurrence rate was 19.0% (8 of 42 patients). The overall locoregional recurrence rate by site was: chest wall—8.7% (11 of 126 patients), axilla—8.7% (11 of 126 patients), supraclavicular—5.6% (7 of 126 patients), and neck—4.0% (5 of 126 patients). The axillary recurrence rate was 6.6% (5 of 76 patients) for clinically negative axilla treated with radiotherapy only, and 12.0% (6 of 50 patients) for clinically positive axilla treated with surgery only. The overall long-term survival probabilities (6 years) according to stage were: stage IIIA—58.0%, stage IIIBnoninflam—58.0%, stage IIIBinflam—36.0%. Conclusions: These findings support a selective approach to local therapy in patients with stage IIIA,B breast cancer. This approach provides local control in most patients, and allows for breast preservation and elimination of axillary dissection in selected patients