PARIS, France--Radiation therapy is a reasonable alternative to mastectomy in women with stage IIIA and IIIB breast cancer who respond to aggressive chemohormonal therapy, a prospective trial conducted at the University of Michigan has found.
The 91 women enrolled in this study received nine cycles of a hormonal synchronization regimen consisting of cyclophosphamide(Drug information on cyclophosphamide), doxorubicin(Drug information on doxorubicin), methotrexate(Drug information on methotrexate), and fluorouracil(Drug information on fluorouracil) with conjugated estrogens(Drug information on estrogens) and tamoxifen(Drug information on tamoxifen) (Nolvadex).
The nearly 30% of patients evaluated who showed a complete pathologic response to induction therapy went on to receive radiation therapy to the breast (median dose, 5,000 cGy), tumor bed (6,400 cGy), supraclavicular fossa (4,500 cGy), and axilla (4,500 cGy), with concomitant chemotherapy followed by eight additional rounds of maintenance chemotherapy, Lori Pierce, MD, said at the American Radium Society meeting.
Women who exhibited residual tumor on surgical biopsy underwent modified radical mastectomy followed by irradiation to the chest wall (median dose, 5,000 cGy), scar (6,000 cGy), and supraclavicular fossa (4,500 cGy), and nine cycles of maintenance chemotherapy.
Both groups of women were comparable in terms of primary tumor size, nodal status, stage at presentation, age, and menopausal status, Dr. Pierce said.
The 5-year local-regional control rate of 82% in women treated with breast-conserving therapy was similar to the 5-year control rate of 75% among the surgically treated patients, said Dr. Pierce, of the Department of Radiation Oncol-ogy, University of Michigan Medical Center, Ann Arbor.
"When we did a multivariate analysis we found no factors that would independently predict for local failure, but we did find that survival was significantly worse in patients with stage IIIB disease than in those with IIIA disease," she said.