Off-label use of oxaliplatin in patients with metastatic breast cancer

Oxaliplatin is an anticancer agent only approved for treatment of colorectal cancer, but that has shown some activity in metastatic breast cancer in phase II studies. Herein, we examine the off-label use of oxaliplatin in unselected patients with metastatic breast cancer.

A retrospective review was performed of all patients with metastatic breast cancer treated with oxaliplatin at our hospital between February 2003 and November 2009. Data concerning patterns of use, safety and activity were collected from patient charts.

The cohort comprised 30 female patients with a median age of 49 (range, 34-68 years) and a median of two involved organs (range, 1-4). All patients had been pretreated for metastatic breast cancer (median number of previous lines: 3; range:1-6). Oxaliplatin was only given in association either with fluorouracil and folinic acid (n=23) or with gemcitabine (n=7). The most commonly used dose was 100 mg/m(2) given every other week or every 3 weeks. As of December 15, 2009, the median duration of treatment was 4 (range, 0.75-11) months. Most of the discontinuations occured due to disease progression (n=11) and adverse effects or worsening condition (n=8). Twelve (40%) patients presented side-effects related to oxaliplatin use including hematotoxicity (n=8), gastrointestinal disorders (n=4) and neuropathies (n=2). Among patients evaluable for antitumoral activity (n=15), one patient achieved a complete response and one patient demonstrated a partial response. Most of the patients (57%) continued to be treated by chemotherapy after oxaliplatin. Median overall survival for the evaluable patients was 10 (range, 1-51) months.

In our population of heavily pretreated women with metastatic breast cancer, off-label use of oxaliplatin was of little worth. This off-label treatment was not the last therapeutic option for most of these patients.