Summary

This randomized phase III trial studies how well doxorubicin hydrochloride and cyclophosphamide followed by paclitaxel with or without carboplatin work in treating patients with triple-negative breast cancer. Drugs used in chemotherapy, such as doxorubicin hydrochloride, cyclophosphamide, paclitaxel, and carboplatin, work in different ways to stop the growth of tumor cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. It is not yet known whether doxorubicin hydrochloride and cyclophosphamide is more effective when followed by paclitaxel alone or paclitaxel and carboplatin in treating triple-negative breast cancer.

Objectives

PRIMARY OBJECTIVES:
I. To determine whether the addition of carboplatin to an adjuvant chemotherapy regimen of doxorubicin (doxorubicin hydrochloride)/cyclophosphamide followed by paclitaxel will improve the invasive disease-free survival (IDFS) compared to doxorubicin/cyclophosphamide followed by paclitaxel when administered to patients with operable node-positive or high-risk node-negative triple-negative breast cancer.

SECONDARY OBJECTIVES:
I. To determine whether the addition of carboplatin to an adjuvant chemotherapy regimen of doxorubicin/cyclophosphamide followed by paclitaxel will improve the overall survival (OS) compared to doxorubicin/cyclophosphamide followed by paclitaxel when administered to patients with operable node-positive or high-risk node-negative triple-negative breast cancer.
II. To determine whether the addition of carboplatin to an adjuvant chemotherapy regimen of doxorubicin/cyclophosphamide followed by paclitaxel will improve the breast cancer-free survival (BCFS) compared to doxorubicin/cyclophosphamide followed by paclitaxel when administered to patients with operable node-positive or high-risk node-negative triple-negative breast cancer.
III. To determine whether the addition of carboplatin to an adjuvant chemotherapy regimen of doxorubicin/cyclophosphamide followed by paclitaxel will improve the recurrence-free interval (RFI) compared to doxorubicin/cyclophosphamide followed by paclitaxel when administered to patients with operable node-positive or high-risk node-negative triple-negative breast cancer.
IV. To determine whether the addition of carboplatin to an adjuvant chemotherapy regimen of doxorubicin/cyclophosphamide followed by paclitaxel will improve the distant recurrence-free interval (DRFI) compared to doxorubicin/cyclophosphamide followed by paclitaxel when administered to patients with operable node-positive or high-risk node-negative triple-negative breast cancer.
V. To determine the toxicity of doxorubicin/cyclophosphamide followed by paclitaxel administered concurrently with carboplatin compared to the toxicity of doxorubicin/cyclophosphamide followed by paclitaxel alone.
VI. To determine if germline BRCA status is associated with benefit in IDFS or OS from the addition of carboplatin to an adjuvant chemotherapy regimen of doxorubicin/cyclophosphamide followed by paclitaxel in patients with operable node-positive or high-risk node-negative triple-negative breast cancer.
VII. To determine if the addition of carboplatin will improve the RFI among the homologous recombination (HR) deficient patients as determined by the homologous recombination deficiency (HRD) score.
VIII. To determine whether the efficacy of carboplatin on RFI in HR-deficient patients differs from that in patients who are not HR-deficient.
IX. To collect tissue and blood samples at several occasions for future biomarkers development in predicting risk of breast cancer recurrence in patients with operable node-positive or high-risk node-negative triple-negative breast cancer treated with doxorubicin/cyclophosphamide followed by paclitaxel with or without carboplatin and predicting benefit from the addition of carboplatin among these patients.

OUTLINE: Patients are randomized to 1 of 2 treatment arms.

ARM I (DOXORUBICIN HYDROCHLORIDE [A] CYCLOPHOSPHAMIDE [C]-->WEEKLY PACLITAXEL [WP]): Patients receive doxorubicin hydrochloride intravenously (IV) over 15 minutes and cyclophosphamide IV over 30 minutes on day 1. Treatment repeats every 2 weeks for 4 cycles in the absence of disease progression or unacceptable toxicity. Patients then receive paclitaxel IV over 60 minutes on day 1. Treatment repeats weekly for 12 cycles in the absence of disease progression or unacceptable toxicity.

ARM II (AC-->WP + CARBOPLATIN): Patients receive doxorubicin hydrochloride and cyclophosphamide as in Arm I. Patients then receive paclitaxel IV over 60 minutes on days 1, 8, and 15 and carboplatin IV over 30-60 minutes on day 1. Treatment repeats every 3 weeks for 4 cycles in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed up every 6 months for 5 years and then every 12 months for 5 years.