Pattern of failure in patients with inflammatory breast cancer treated by alternating radiotherapy and chemotherapy

Patients with inflammatory breast cancer have a high risk of developing a local recurrence and/or distant metastases. Treatment with combined chemotherapy and locoregional radiotherapy contributes to a decrease in both risks. This study presents treatment results and evaluates the pattern of failure when an alternating chemoradiotherapy schedule is used.

One hundred twenty-five patients with nonmetastatic inflammatory breast cancer were treated with an alternating schedule of radiotherapy and chemotherapy. All women recruited were younger than 70 years of age and had a T4d, histologically proven infiltrating carcinoma with N0 to N2 axillary disease. The protocol consisted of three cycles of induction chemotherapy with doxorubicin, vincristine, cyclophosphamide, methotrexate, and 5-fluorouracil followed by three series of locoregional radiotherapy, delivering a total dose of 65-75 Gy to the breast tumor. Five additional cycles of chemotherapy with 5-fluorouracil/doxorubicin/cyclophosphamide were to be administered in between the first two and after the third radiotherapy course. A 1-week gap was respected between each course of chemotherapy and each series of radiotherapy.

Toxicity was moderate and this strategy proved feasible although most of the patients only received six instead of the eight planned cycles of chemotherapy. Eighty-two percent of the patients achieved a complete response at the end of the treatment. The cumulative 5-year local failure and distant metastasis rates were 27% and 53%, respectively. Assuming competing events, local failures, contralateral recurrences, and distant metastases were the first site of failure in 18%, 5%, and 38% of patients, respectively. The 5-year overall and disease free survival rates were 50% and 38%, respectively. The main prognostic factor was tumor size.

Alternating high doses of radiotherapy and chemotherapy is a feasible treatment schedule and permits breast conservation. Disease free survival is comparable to that of recently published series. As the main causes of failure are distant metastases, higher dose chemotherapy should be evaluated, in an attempt to further improve overall survival.