Treatment of locally recurrent or high-risk carcinoma of the breast with radiation therapy and weekly docetaxel given as a radiosensitizer

Abstract

11538 Background: Uncontrolled breast cancer involving the chest wall continues to be a major source of morbidity. Docetaxel has proven to be a good radiation sensitizer, causing cells to arrest during the most radiation sensitive phase of the cell cycle, G2/M. The goal of this trial is to determine the feasibility of delivering docetaxel during radiation therapy (XRT). Methods: Post-mastectomy patients at high risk of local failure because of tumor size, poor response to induction chemotherapy, extensive nodal involvement, inflammatory breast cancer (IBC) or recurrent disease were eligible. Conventional XRT (1.8 to 2.0 Gy/day, 5 days/week to 50.4 Gy to chest wall/supraclavicular areas), followed by an optional boost to 10 to 12.0 Gy. Docetaxel, 20 mg/M2 was given intravenously weekly. The primary objective was toxicity as defined using Common Toxicity Criteria. Secondary objectives included time to progression (TTP), and response rate. Results: Four centers enrolled 33 women. One patient was excluded after an allergic reaction to docetaxel. Eight patients had measurable disease, nine had recurrent disease, twenty-three were newly diagnosed, and three had IBC. One patient received less than 50 Gy. Five patients received less then 6 cycles of docetaxel. All patients had radiation dermatitis. Four patients (8%) had grade 3 desquamation; none had grade 4 or 5. Chest wall/axillary or arm pain occurred in eleven patients. Grade 1–2 or grade 3 hematologic toxicity occurred in six and two patients respectively. Grade 1 neuropathy in three patients. Grade 1–2 nausea/vomiting occurred in eight patients. Grade 1–2 diarrhea occurred in three patients. Of eight patients with measurable disease all responded, four achieved complete response. Mean TTP was 19.16 months. Five local failures occurred at 13–28 months. Conclusions: The administration of low-dose weekly docetaxel during radiotherapy to the chest wall for is feasible. Further studies are needed to evaluate ideal dosing and impact on PFS. No significant financial relationships to disclose.