High-dose chemotherapy with peripheral blood stem cell transplantation as adjuvant therapy for primary breast cancer with extensive lymph node involvement

Eighteen patients with breast cancer involving more than 10 regional lymph nodes were treated by high-dose chemotherapy (HDCT) supported by peripheral blood stem cell plantation (PBSCT) as adjuvant therapy. After radical mastectomy, the combination chemotherapy with adriamycin 50 mg/m², cyclophosphamide 1,000 mg/m², vincristine 1.0 mg/m² and methotrexate 200 mg/m² with leucovorin rescue was started, and repeated every 3 weeks for 3 courses. G-CSF was also given. After the 2nd and 3rd courses, PBSCs were collected and cryopreserved. Tamoxifen was also given to patients with breast cancer containing a high concentration of estrogen receptor, and radiation therapy for supra-clavicular and parasternal lymph nodes was also combined. Finally, HD-CT with thio-TEPA 200 mg/m²/day, etoposide 300 mg/m²/day, and CPA 2,000 mg/m²/day were administered for 3 consecutive days, and after 72 hours of final doses, frozen-thawed PBSC were administered. HD-CT with PBSCT was well tolerated, and recovery from myelosuppression of the HD-CT was rather quick and no serious side effects were observed. Fifteen patients remained in remission with a median follow-up of 33 months after mastectomy, and three relapsed at 13, 19 and 21 months after surgery. According to Kaplan-Meyer analysis, the probability of disease-free survival was significantly higher in patients treated by HDCT with PBSCT as compared with those treated by conventional chemotherapy in our division, showing 75.7 % and 24.6 % respectively, at 5 years after mastectomy. HD-CT with PBSCT as adjuvant therapy for primary breast cancer with extensive lymph node involvement may improve the supposed poor prognosis of such patients.