Autologous stem cell transplantation (also called autogenous, autogeneic, or autogenic stem-cell transplantation and abbreviated auto-SCT) is autologous transplantation of stem cells—that is, transplantation in which stem cells (undifferentiated cells from which other cell types develop) are removed from a person, stored, and later given back to that same person. Although it is most frequently performed with hematopoietic stem cells (precursors of blood-forming cells) in hematopoietic stem cell transplantation, cardiac cells have also been used successfully to repair damage caused by heart attacks.
Autologous stem-cell transplantation is distinguished from allogenic stem cell transplantation where the donor and the recipient of the stem cells are different people.
The number of studies examining the use of tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) to treat high-risk or recurrent brain tumors is increasing.
Lee et al., retrospectively reviewed the medical records of 30 patients with High Grade Gliomas (HGGs) (16 glioblastomas, 7 anaplastic astrocytomas, and 7 other HGGs) between 2006 and 2015. Gross total resection or near total resection was possible in 11 patients. Front-line treatment after surgery was radiotherapy (RT) in 14 patients and chemotherapy in the remaining 16 patients including 3 patients less than 3 years of age. Eight of 12 patients who remained progression free and 5 of the remaining 18 patients who experienced progression during induction treatment underwent the first high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) with carboplatin + thiotepa + etoposide (CTE) regimen and 11 of them proceeded to the second HDCT/auto-SCT with cyclophosphamide + melphalan (CyM) regimen. One patient died from hepatic veno-occlusive disease (VOD) during the second HDCT/auto-SCT; otherwise, toxicities were manageable. Four patients in complete response (CR) and 3 of 7 patients in partial response (PR) or second PR at the first HDCT/auto-SCT remained event free: however, 2 patients with progressive tumor experienced progression again. The probabilities of 3-year overall survival (OS) after the first HDCT/auto-SCT in 11 patients in CR, PR, or second PR was 58.2% ± 16.9%. Tumor status at the first HDCT/auto-SCT was the only significant factor for outcome after HDCT/auto-SCT. There was no difference in survival between glioblastoma and other HGGs. This study suggests that the outcome of HGGs in children and adolescents after HDCT/auto-SCT is encouraging if the patient could achieve CR or PR before HDCT/auto-SCT 1).
Sung et al., prospectively evaluated the effectiveness of tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) in improving the survival of patients with Atypical teratoid rhabdoid tumors while reducing the risks of late adverse effects from radiotherapy (RT).
For young children (< 3 years old), tandem HDCT/auto-SCT was administered after six cycles of induction chemotherapy. RT was deferred until after 3 years of age unless the tumor showed relapse or progression. For older patients (> 3 years old), RT including reduced-dose craniospinal RT (23.4 or 30.6 Gy) was administered either after two cycles of induction chemotherapy or after surgery, and tandem HDCT/auto-SCT was administered after six cycles of induction chemotherapy.
A total of 13 patients (five young and eight older) were enrolled from November 2004 to June 2012. Eight patients, including all five young patients, had metastatic disease at diagnosis. Six patients (four young and two older) experienced progression before initiation of RT, and seven were able to proceed to HDCT/auto-SCT without progression during induction treatment. Three of six patients who experienced progression during induction treatment underwent HDCT/auto-SCT as salvage treatment. All five young patients died from disease progression. However, four of the eight older patients remain progression-freewith a median follow-up period of 64 months (range, 39 to 108 months). Treatment-related late toxicities were acceptable.
The required dose of craniospinal RT might be reduced in older patients if the intensity of chemotherapy is increased. However, early administration of RT should be considered to prevent early progression in young patients 2).
Choi et al., retrospectively analyzed infectious complications during tandem high-dose chemotherapy and autologous stem cell transplantation (HDCT/auto-SCT) in children and adolescents with high-risk or recurrent solid tumors. A total of 324 patients underwent their first HDCT/auto-SCT between October 2004 and September 2014, and 283 of them proceeded to their second HDCT/auto-SCT (a total of 607 HDCT/auto-SCTs). During the early transplant period of 607 HDCT/auto-SCTs (from the beginning of HDCT to day 30 post-transplant), bacteremia, urinary tract infection (UTI), respiratory virus infection, and varicella zoster virus (VZV) reactivation occurred in 7.1%, 2.3%, 13.0%, and 2.5% of HDCT/auto-SCTs, respectively. The early transplant period of the second HDCT/auto-SCT had infectious complications similar to the first HDCT/auto-SCT. During the late transplant period of HDCT/auto-SCT (from day 31 to 1 year post-transplant), bacteremia, UTI, and VZV reactivation occurred in 7.5%, 2.5%, and 3.9% of patients, respectively. Most infectious complications in the late transplant period occurred during the first 6 months post-transplant. There were no invasive fungal infections during the study period. Six patients died from infectious complications (4 from bacterial sepsis and 2 from respiratory virus infection).This study suggests that infectious complications are similar following second and first HDCT/auto-SCT in children 3).
Lee et al., retrospectively evaluated the toxicity of tandem HDCT/auto-SCT with carboplatin-thiotepa-etoposide (CTE) and cyclophosphamide-melphalan (CM) regimens when used to treat high-risk or recurrent brain tumors. A total of 109 patients who received a first HDCT/auto-SCT and 100 who proceeded to a second HDCT/auto-SCT between May 2005 and December 2013 were included. Hematologic recovery was rapid during both the first and second HDCT/auto-SCT. In the first HDCT/auto-SCT, mucositis-related gastrointestinal toxicity was frequent, and two (1.8 %) patients died from toxicity [one hepatic veno-occlusive disease (VOD) and one sepsis]. In the second HDCT/auto-SCT, mucositis-related toxicity was milder than in the first round. However, hepatic VOD frequency was high (20.0 %), and six (6.0 %) patients died from toxicity (four hepatic VODs, one asphyxia, and one sepsis). Multivariate analysis indicated that age younger than 8 years was the only significant predictor for hepatic VOD. All six patients who died from toxicity during the second HDCT/auto-SCT were younger than 9 years of age. This study demonstrates that tandem HDCT/auto-SCT using CTE/CM regimens was generally feasible. However, dose reduction during the second HDCT/auto-SCT in young children might be needed to decrease the death rate from toxicity 4).
From January 2004 to December 2008, 50 consecutive patients with high-risk neuroblastoma were assigned to receive tandem HDCT (high-dose chemotherapy)/auto-SCT after nine cycles of induction chemotherapy. CEC (carboplatin + etoposide + cyclophosphamide) regimen and TM (thiotepa + melphalan)-TBI regimen (or TM regimen for stage 3 patients) were the first and second HDCT regimens. Local radiotherapy, differentiation therapy with 13-cis-retinoid acid and immunotherapy with interleukin-2 were given after tandem HDCT/auto-SCT. Of the 50 patients, 49 underwent a first HDCT/auto-SCT and 47 underwent a second HDCT/auto-SCT. The tumor relapsed or progressed in 14 patients, secondary malignancy developed in one patient and one patient died from chronic lung disease. Therefore, 34 patients remained event free with a median follow-up of 54.5 months (range, 14-94 months) from diagnosis. The probabilities of 5-year OS and EFS for all 50 patients were 77.0% (95% confidence interval (CI), 63.7-90.3) and 71.4% (95% CI, 58.7-84.1), respectively. However, all patients who remained event free for >3 years after tandem HDCT/auto-SCT experienced late adverse effects. Chemotherapeutic dose-escalation strategy using tandem HDCT/auto-SCT was very encouraging for survival. However, further studies incorporating newer treatment modalities are needed to reduce late adverse effects without jeopardizing the survival rate 5).