Myeloablative chemotherapy with autologous peripheral blood stem cell transplantation in patients with poor-prognosis solid tumors - Bulgarian experience.

To assess the outcome of patients with refractory or relapsed solid tumors treated with myeloablative chemotherapy followed by autologous peripheral blood stem cell transplantation. From October 1997 to March 2006, 38 transplantations were performed in 32 patients (19 children and 13 adults, 20 men and 12 women, median age 18.5 years, range 3 - 59). Six patients underwent 2 transplantations. The diagnoses were: rhabdomyosarcoma-4; Ewing's sarcoma -7; lymphoepithelioma epipharyngis -7; germ-cell tumors -6; neuroblastoma -4; pulmonary blastoma -1; breast cancer -3. The indication for high-dose chemotherapy was sensitive relapse in 17 and refractory disease in 15 patients. At the time of transplantation the state of remission was: complete remission (CR) in 10 patients; partial remission (PR) in 16 and disease progression in 6. The median number of transplanted CD34+ cells was 4.49 x 10(6)/kg of patient's body weight. High-dose chemotherapy regimens were: thiotepa, carboplatin - 1; thiotepa, cyclophosphamide - 5; ifosfamide, carboplatin, etoposide (ICE) - 18; etoposide, carboplatin - 2; etoposide, cyclophosphamide, melphalan - 2; melphalan, fludarabine - 1; melphalan, busulfan - 3; etoposide, carboplatin, ifosfamide/thiotepa, cyclophosphamide (EBDIS) - 4. Twenty-nine patients were engrafted and 3 died from graft failure. Transplantation-related mortality was 9%. The most important transplantation-related toxicities included mucositis (90% of the patients), fever (85%) and diarrhea (75%). With a median follow-up of 32 months (range 1-95), the median overall survival (OS) and the event-free survival (EFS) were 62 and 36 months, respectively. High-dose chemotherapy with autologous stem cell transplantation was curative for many of our patients with poor-prognosis solid tumors.