study of tissue samples from women treated with paclitaxel for breast cancer on clinical trial calgb-9344 or calgb-9741

Conditions: Breast Cancer

Summary: rationale: studying the genes expressed in samples of tumor tissue from patients with cancer may help doctors identify biomarkers related to cancer. purpose: this research study is looking at tissue samples from women treated with paclitaxel for breast cancer on clinical trial calgb 9344 or calgb 9741.

objectives: primary * to determine whether subtype-specific treatment effects correlate with disease-free survival (dfs), as determined by a significant interaction between pam50-based intrinsic subtypes, and (a) paclitaxel benefit in clb-9344 and (b) dose density in calgb-9741. * to determine whether subtype-specific treatment effects correlate with dfs for the her2-negative subsets in calgb-9344 and calgb-9741, as determined by analysis of tissue microarray (tma) and slides. * to determine the relationship between pam50-defined risk of relapse (ror) score and dfs in calgb-9344 and calgb-9741. * to evaluate the relationship between pam50-defined ror score and dfs in the her2-negative subsets in calgb-9344 and calgb-9741, as determined by analysis of tma and slides. * to examine the relationship between pam50-defined proliferation score and dfs in calgb-9344 and calgb-9741 in multivariate cox-proportional hazards models including the following covariates: (a) number of positive lymph nodes, square root transformation; (b) menopausal status (pre versus peri/post); calgb-9344 only; c) dose of doxorubicin hydrochloride (60/75/90 mg/m\^2); and calgb-9741 only; and (d) sequence of treatment. secondary * to evaluate overall survival (os) in a cox-proportional hazards-regression model for testing the interaction between ror with (a) paclitaxel benefit in calgb-9344 and (b) dose density in calgb-9741. * to test for a significant interaction between ror and paclitaxel benefit at 5-year and 10-year dfs. * to test whether 5-year and 10-year dfs rates can be associated to a significant interaction between the proliferation score with (a) paclitaxel benefit in calgb-9344 and (b) dose density in calgb-9741. outline: tissue blocks from calgb-9344 and calgb-9741 are utilized to purify rna to be tested in the pam50 assay (a 50-gene quantitative pcr assay, that provides an intrinsic breast cancer subtype diagnosis) and generate risk of relapse (ror) scores. the assay identifies five subtypes with the following characteristics: * luminal a: this subtype expresses estrogen receptor (er) accompanied by high levels of er-associated gene expression. genes associated with cell cycle activation are not highly expressed and this tumor type is only very rarely her2+. this subgroup has the most favorable prognosis and is enriched for endocrine therapy responsive tumors. * luminal b: this subtype expresses er and er-associated gene expression but to a lower extent. genes associated with cell cycle activation are highly expressed and this tumor type can be her2+ (\~20%) or her2- thus, from the clinical perspective, luminal b tumors are at least two further subtypes defined by the presence or absence of her2-gene amplification. the prognosis is unfavorable (despite er expression) and endocrine therapy responsiveness is generally diminished. * basal-like: this subtype is er-, is almost always clinically her2- and expresses a suite of "basal" biomarkers. genes associated with cell cycle activation are highly expressed. * her2-enriched: this subtype is er- and is her2+ in the majority of cases. genes associated with cell cycle activation are highly expressed and these tumors have a poor outcome. tumors within this classification that are clinically her2- fall into a class previously described as double-negative non-basal. * normal-like: a tumor subtype diagnosis cannot be provided from samples that exhibit a normal-like profile. since this profile was trained on samples without cancer, "normal-like" implies there are too few tumor cells in the sample to make a true tumor subtype diagnosis. projected accrual: a total of 2,245 tissue blocks from calgb-9544 and 1,432 tissue blocks from calgb-9741 will be accrued for this study.

Eligibility criteria:
disease characteristics: * diagnosis of stage ii or iiia breast cancer * received treatment with paclitaxel on clinical trial calgb-9344 or calgb-9741 * tissue blocks available patient characteristics: * see disease characteristics * pre-, peri-, or postmenopausal prior concurrent therapy: * see disease characteristics

Keywords: stage ii breast cancer stage iiia breast cancer