[Complications after high dose therapy and autologous stem cell transplantation. Retrospective study of an unselected patient sample].

BACKGROUND: High-dose therapy (HDT) with autologous blood stem cell transplantation (ASCT) has become the therapy of choice for patients with specific hematologic neoplasms. Although pancytopenia after HDT with stem cell support is of relatively short duration, complications may be severe and life-threatening. In unselected patients with hematologic and solid tumor malignancies, only few data have been published regarding complications. We therefore analyzed the rate of infection and toxicity in patients with different neoplasms undergoing HDT and ASCT.

PATIENTS AND METHODS: From 6/96 to 12/99 42 patients received 54 HDT and ASCT (nine tandem transplants and one triple transplant). The median age was 55 years (range 25-74 years) with equal sex distribution. 30 patients suffered from hematologic malignancies and twelve from solid tumors.

RESULTS: Infections were the major cause for complications followed by mucositis, pain and diarrhea. In four patients a positive cytomegalovirus polymerase chain reaction (CMV-PCR) was detected. In two patients this positive test result was accompanied by clinical symptoms of CMV infection. One patient developed lung fibrosis due to busulfan (WHO 4 degrees) and additionally a veno-occlusive disease (VOD) of the liver (WHO 4 degrees). Two patients (4%) died due to CMV pneumonia and multiple organ failure after idiopathic pneumonia, respectively. Four patients developed secondary neoplasms (two patients myelodysplastic syndromes, two patients solid tumors). Three of them had been heavily pretreated. We further analyzed whether the following parameters had an influence on the rate of complications: tumor diagnosis (hematologic vs. solid), number of pretreatment protocols (< 2 vs. > or = 2), CD34+ cell count (< median CD34+ cell count vs. > or = median CD34+ cell count), age (< or = 55 years vs. > 55 years), mucositis (WHO 1-2 degrees vs. 3-4 degrees) and conditioning regimen (myeloablative vs. myelosuppressive). The infection rate was higher in patients receiving myeloablative therapy compared to patients with myelosuppressive conditioning and the platelet count recovery was slower. In patients receiving a higher CD34+ cell count, time until platelets reached > 50/nl was shorter than in patients with a lower CD34+ cell count. Patients with > or = 2 pretreatment protocols had a higher infection rate than patients with < 2 pretreatments. Patients suffering from severe mucositis (WHO 3-4 degrees) exhibited a slower platelet recovery and a higher infection rate. No difference was noted in the complication rate for the other parameters (tumor diagnosis, age).

CONCLUSION: Complication rate and mortality in this heterogeneous patient group were not different from the data of other authors describing selected patients receiving a uniform conditioning regimen or having a distinct disease. The complication rate is influenced by the number of pretreatment protocols, conditioning regimens and the number of transplanted CD34+ cells.