Feasibility and low toxicity of early radiotherapy after high-dose chemotherapy and autologous stem cell transplantation for patients with high-risk stage II-III and locally advanced breast carcinoma

BACKGROUND, This prospective trial examined the feasibility toxicity, and e ffectiveness of early locoregional radiotherapy after high-dose chemotherap y and autologous stem cell transplantation in patients with high-risk Ameri can Joint Committee on Cancer WCC) Stage II-III and locally advanced breast carcinoma. METHODS, One hundred forty-seven consecutive patients with high-risk and lo cally advanced breast carcinoma were included in the current study. All pat ients received induction chemotherapy with a doxorubicin-based therapy, whi ch was consolidated with high-dose cyclophosphamide, carboplatin, and thiot epa followed by autologous stem cell support. Within 50 days of the transpl ant, the patients were treated with locoregional radiotherapy that included the chest wall or breast, the axilla and supraclavicular area, and the int ernal mammary chain. The volume of lung included in the treatment volume wa s kept to a minimum. The central lung distance of the tangential fields ran ged from 0.6-2.0 cm (mean, 1.1 cm). Tamoxifen was given based on receptor s tatus. RESULTS, One hundred forty-six of 147 patients received the planned treatme nt. Only six patients had a delay in the initiation of radiotherapy, and an other 16 patients had delays during radiotherapy. Leukocyte and platelet to xicities during radiotherapy were not life-threatening and blood counts the reafter returned to normal. Grade 2 (according to National Cancer Institute Common Toxicity Criteria) skin toxicity occurred in 22% of patients and Gr ade 3 skin toxicity occurred in 6% of patients. Radiation pneumonitis was r eported to occur in 5 patients (< 4%). After a median follow-up of 36 month s from diagnosis (range, 6 - 64 months), there were no long-term organ toxi city and no secondary malignancy reported. No treatment-related deaths were reported. Three patients (< 3%) developed locoregional recurrence. CONCLUSIONS. Locoregional radiotherapy after high-dose chemotherapy and aut ologous stem cell transplantation appears to be feasible and can be deliver ed safely within 10 weeks of transplantation. The short-term and long-term toxicity are reported to be low, with good local control. Cancer 2001;91:19 83-91, (C) 2001 American Cancer Society.