[High-dosage chemotherapy and the autologous transplantation of peripheral hematopoietic progenitor cells in breast cancer: the initial results, analysis of toxicity and the necessary support means].

Background: In the last years high dose chemotherapy (HDC) schedules have been developed with autologous bone marrow transplantation (ABMT) which are very effective in breast cancer. Expectation has been raised concerning the cure of a subgroup of patients with metastatic breast cancer and the improvement of prognosis in high risk stages II and III.

Methods: CTCb (cyclophosphamide 6 g/m2, thiotepa 500 mg/m2 and carboplatin 800 mg/m2) was administered with autologous peripheral hematopoietic progenitor cells transplantation (TACPHP) and granulocytic colony stimulating factor (G-CSF) 5 micrograms/kg/day to 27 patients with breast cancer: 9 in stage IV in complete remission, 12 in stage II with > or = 10 affected lymph nodes and 6 in stage III.

Results: No toxic deaths were reported. The median time to achieve > or = 0.5 x 10(9) neutrophils/l was 8 days, to > or = 20 x 10(9) platelets/l 9 days and to > or = 50 x 10(9) platelets/l 12 days. Fever was observed in 85% of the patients although its median duration was of only one day. Extrahematologic toxicity was moderate with grade III nausea/vomiting in 48% of patients, grade III mucositis in 22%, grade III hepatitis in 19%, and grade III diarrhea in 4%. No grade IV toxicity was observed. The median follow-up is still short (10 months, range: 2-25). All the patients maintain normal hematologic peripheral blood counts and only 4 (in stage IV) have relapsed.

Conclusions: The slight extrahematologic toxicity observed in the high dose chemotherapy with cyclophosphamide, thiotepa and carboplatin, and the rapid hematologic recovery provided by the TACPHP and G-CSF allow the above schedule to be administered with moderate toxicity and no mortality. This low toxic profile leads to the possibility of future trials with this chemotherapy schedule in other subgroups of patients with breast cancer.