Double-alkylator non-total-body irradiation regimen with autologous hematopoietic stem-cell transplantation in pediatric solid tumors

Autologous hematopoietic stem cell transplantation for pediatric solid tumors

While advances in the treatment of pediatric cancers have increased cure rates, children with metastatic or recurrent solid tumors have a dismal prognosis despite initial transient responses to therapy. Autologous hematopoietic stem cell transplantation takes advantage of the steep dose-response relationship observed with many chemotherapeutic agents. While clearly demonstrated to improve outcomes in patients with metastatic neuroblastoma, autologous hematopoietic stem cell transplantation is also frequently used to treat patients with other high-risk diseases such as Ewing sarcoma, osteosarcoma, rhabdomyosarcoma, Wilms' tumor, retinoblastoma, germ cell tumors, lymphomas and brain tumors. Most published experience consists of retrospective, single-arm studies; randomized clinical trials are lacking, due in part to the rarity of pediatric cancers treatable by autologous hematopoietic stem cell transplantation. These published literature demonstrate that autologous hematopoietic stem cell transplantation results in most cases in equivalent or superior outcomes when compared with conventional therapies. However, patient heterogeneity, patient selection, graft characteristics and processing and the varied conditioning regimens are additional factors to consider. Since the inception of autologous hematopoietic stem cell transplantation, regimen-related toxicity has markedly decreased and the vast majority of treatment failures are now due to disease recurrence. Prospective clinical trials are needed to identify specific high-risk patient populations, with randomization (when possible) to compare outcomes of patients undergoing autologous hematopoietic stem cell transplantation with those receiving standard therapy. In addition, investigators need to better define the role of autologous hematopoietic stem cell transplantation in these solid tumors, particularly in combination with other therapeutic modalities such as immunotherapy and novel cell processing methodologies.

The role of high-dose therapy and autologous stem cell transplantation for pediatric bone and soft tissue sarcomas

The prognosis for children with bone and soft tissue sarcomas has significantly improved since the advent of effective multiagent chemotherapy, aggressive surgery for local disease and more precise delivery of radiotherapy doses. However, in a small proportion of patients that present with high-risk disease, long-term outcome has not substantially increased, with disease-free survival rates still in the order of 20-30%. It is therefore clear that novel therapies are needed for children with these tumors. Based on the highly chemosensitive nature of the majority of pediatric sarcomas, several small studies have been conducted to investigate the potential role of high-dose chemotherapy followed by hematopoietic stem cell reconstitution. This review will provide an overview of the current literature concerning the use of high-dose therapy with stem cell transplantation for the three main pediatric sarcomas--Ewing sarcoma, rhabdomyosarcoma and osteosarcoma.

Consolidation treatment for high risk solid tumors in children with myeloablative chemotherapy and autologous hematopoietic progenitor stem cell transplantation

Background

In childhood cancer, consolidation treatment with chemotherapy followed by autologous hematopoietic progenitor stem cell transplantation is currently an accepted treatment modality in patients with high-risk solid tumors or in patients who have relapsed after conventional treatment.

Objectives

The objective of this study was to describe the results of transplantation of a group of children who had high-risk solid tumors or relapsed after conventional chemotherapy regimens.

Methods

A retrospective analysis was conducted from January 1998 to October 2004 of all children with pathologic diagnoses of high-risk solid tumors or children that had previously relapsed after conventional chemotherapy and that were subsequently submitted to autologous hematopoietic progenitor stem cell transplantation. The analysis included overall survival rates, event-free survival rates, mortality rates and chemotherapy complications.

Results

Nineteen patients were submitted to this approach. The age range was from 27 to 196 months with a median age of 52 months. The overall survival rate at 100 days was observed in 79%, the three-year event-free survival rate was 63%. The mortality rate secondary to the myeloablative chemotherapy regimen was 21% (n = 4). Only three patients (15.8%) relapsed with tumor progression after transplant.

Conclusion

Autologous hematopoietic progenitor stem cell transplantation is still a successful procedure in patients with solid tumors refractory to conventional chemotherapy.

Clinical pharmacology of etoposide in children undergoing autologous stem cell transplantation for various solid tumours

1. The population pharmacokinetics of high-dose etoposide was studied in a group of young children and adolescents. 2. Twenty-six children and adolescent were administered high-dose etoposide as a continuous infusion over 24 h. Etoposide plasma concentration-time data was modelled using NONMEM® 7. The effect of age, weight, serum creatinine (SCr), and gender on pharmacokinetic parameters (CL and V(d)) were determined by a nonlinear mixed effect model. 3. The pharmacokinetics of etoposide based on BSA dosing was best described with a 1-compartment structural model which was parameterised in terms of clearance (CL) and volume of distribution (V(d)). An exponential error model was used to explain intersubject variability and a proportional error model was used to describe residual or intrapatient variability. The final model parameter estimates for the typical (normalised to 70 kg) values of CL and V(d) were 2.31 L/hr and 17.5 L, respectively. The CL and V(d) allometrically increased with weight with the power of 3/4 and 1, respectively. After accounting for weight dependence using the allometric scaling, age, serum creatinine, and gender did not have any influence on model parameters. 4. The results of this children and adolescent population pharmacokinetic study indicates that etoposide pharmacokinetics were influenced by body weight on an allometric basis. The pharmacokinetic parameters CL and V(d) increased with increasing weight similar to BSA.

Autologous hematopoietic stem cell transplantation following high-dose chemotherapy for non-rhabdomyosarcoma soft tissue sarcomas

BACKGROUND

Soft tissue sarcomas (STS) are a highly heterogeneous group of rare malignant solid tumors. Non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) comprise all STS except rhabdomyosarcoma. In patients with advanced local or metastatic disease, autologous hematopoietic stem cell transplantation (HSCT) applied after high-dose chemotherapy (HDCT) is a planned rescue therapy for HDCT-related severe hematologic toxicity.

OBJECTIVES

To assess the effectiveness and safety of HDCT followed by autologous HSCT for all stages of soft tissue sarcomas in children and adults.

SEARCH STRATEGY

We searched the electronic databases CENTRAL (The Cochrane Library 2010, Issue 2), MEDLINE and EMBASE (February 2010). Online trial registers, congress abstracts and reference lists of reviews were searched and expert panels and authors were contacted.

SELECTION CRITERIA

Terms representing STS and autologous HSCT were required in the title, abstract or keywords. In studies with aggregated data, participants with NRSTS and autologous HSCT had to constitute at least 80% of the data. Comparative non-randomized studies were included because randomized controlled trials (RCTs) were not expected. Case series and case reports were considered for an additional descriptive analysis.

DATA COLLECTION AND ANALYSIS

Study data were recorded by two review authors independently. For studies with no comparator group, we synthesised results for studies reporting aggregate data and conducted a pooled analysis of individual participant data using the Kaplan-Meyer method. The primary outcomes were overall survival (OS) and treatment-related mortality (TRM).

MAIN RESULTS

We included 54 studies, from 467 full texts articles screened (11.5%), reporting on 177 participants that received HSCT and 69 participants that received standard care. Only one study reported comparative data. In the one comparative study, OS at two years after HSCT was estimated as statistically significantly higher (62.3%) compared with participants that received standard care (23.2%). In a single-arm study, the OS two years after HSCT was reported as 20%. In a pooled analysis of the individual data of 54 participants, OS at two years was estimated as 49% (95% CI 34% to 64%). Data on TRM, secondary neoplasia and severe toxicity grade 3 to 4 after transplantation were sparse. All 54 studies had a high risk of bias.

AUTHORS' CONCLUSIONS

Due to a lack of comparative studies, it is unclear whether participants with NRSTS have improved survival from autologous HSCT following HDCT. Owing to this current gap in knowledge, at present HDCT and autologous HSCT for NRSTS should only be used within controlled trials.

28 years of high-dose therapy and SCT for neuroblastoma in Europe: lessons from more than 4000 procedures

Between 1978 and 2006, the European Group for Blood and Marrow Transplantation registered 4098 high-dose therapy (HDT) procedures followed by stem cell rescue (SCR) (3974 autologous/124 allogeneic) in patients with neuroblastoma. The 5-year rates for overall (OS) and event-free survival are 37 and 32%, respectively. The median age at diagnosis is 3.9 years (0.3-62 years) with 76 patients older than 18 years. Patients above 10 years carry a 2.5-fold higher risk. Younger patients cure significantly (<0.001) better with OS rates of 40 and 30% for age groups 2-4 years and 4-10 years, respectively. Their risks are about twofold higher than that of patients below 2 years with OS rates of 60%. The better the quality of remission status before HDT/SCT the better are the observed OS rates: 43% in CR1 (1199 patients) and 42% for CR2 (140 patients), and 36% for those in very good partial or partial remission (1413 patients) and 21% for those with sensitive relapse (134 patients). Patients reported with stable disease in first remission still had an OS rate of 30%. Multivariate analysis shows significantly better OS in the age group of less than 2 years (<0.0001), as well as a better quality of remission status before HDT/SCT (P<0.0001), with the use of peripheral stem cells (P=0.014), autologous SCT (P=0.031) and busulphan/melphalan HDT (P<0.001). Busulphan/melphalan HDT/SCT in first remission achieves an OS of 48%, while it is only 35% with other regimens (P<0.001), including melphalan alone, other melphalan-containing regimens, a variety of other drugs given as a single HDT as well as the addition of TBI or sequential HDT/SCT procedures. Further progress in the field may only be expected from large-scale international randomized trials.

Long-term follow up of high-dose chemotherapy with autologous stem cell rescue in adults with Ewing tumor

Ewing tumors remain of poor prognosis, with 5-year overall survival of 55% to 65% in localized patients and not exceeding 25% in primarily metastatic disease. Several reports, mainly in children, have reported that some patients with poor-risk Ewing tumors may benefit from high-dose chemotherapy (HDCT) with autologous stem cell rescue. This retrospective study analyzed 46 patients treated in our institution between 1987 and 2000 for localized or primary metastatic Ewing tumors by HDCT followed by stem cell rescue. Median follow up was 7.1 years. Median age was 21 years (range, 15-46 years). Twenty-two percent of patients had metastases at diagnosis. The tumor site was axial in 56% of patients. Median tumor size was 9.5 cm. The treatment regimen consisted of induction chemotherapy, local treatment, maintenance chemotherapy, and consolidation HDCT based on alkylating agents. No toxic death was observed in the intensive therapy phase. Five-year overall survival and progression-free survival were 63 +/- 7.7% and 47 +/- 7.6%, respectively. Pejorative prognostic factors in this population were metastases at diagnosis (5-year overall survival 34% vs.71%, P = 0.017) and poor pathologic response (5-year overall survival 44% vs.77%, P = 0.03). This retrospective study shows a high long-term survival rate with high-dose chemotherapy in adults.

Ewing's sarcoma and primitive neuroectodermal family of tumors

Ewing's sarcoma (ES) initially was believed to be of perivascular endothelial origin. The Ewing's sarcoma family of tumors (EFT) includes ES of bone (ESB), extraosseous ES (EES), peripheral primitive neuroectodermal tumor of bone (pPNET), and malignant small-cell tumor of the thoracopulmonary region, or Askin's tumor, all of which are now known to be neoplasms of neuroectodermal origin. The degree of neuronal differentiation has been used for histopathologic subclassification of the EFT as classical ES (ESB or EES), which is characterized by minimal evidence of neural differentiation, and pPNET, which displays evidence of neural differentiation by standard microscopy, electron microscopy, or immunohistochemistry. Because the behavior, prognosis, and treatment appear to be similar for all subsets of EFT, this histopathologic subclassification may not be clinically significant, though some debate remains whether neural differentiation predicts for inferior outcome.

High-dose therapy with autologous stem cell rescue for pediatric sarcomas

PURPOSE OF REVIEW

The principal pediatric sarcomas are Ewing sarcoma, rhabdomyosarcoma, and osteosarcoma. While the prognosis for these diseases is generally favorable, it is possible to identify groups of patients with each diagnosis whose prognosis remains unacceptably poor. Based on the chemotherapy sensitivity of these tumors, many investigators have suggested that consolidation with high dose chemotherapy with or without radiation therapy followed by stem cell rescue could improve the prognosis for these high risk patients. This review evaluates the results of high dose therapy with stem cell reconstitution used to consolidate treatment of high risk patients with sarcomas.

RECENT FINDINGS

The majority of the trials which have been conducted to assess this hypothesis have treated relatively small numbers of patients. They do not use consistent definitions of high risk. They have used different regimens for cytoreduction. They have used a variety of sources for stem cells. In many series, the consolidation therapy is applied only to patients who have achieved a significant response to prior therapy and the results have then been compared to a cohort of patients with similar presenting features, not all of whom responded to initial therapy.

SUMMARY

The published results do not demonstrate an unequivocal benefit for consolidation with high-dose therapy. Future trials of high-dose therapy must define rigorous eligibility criteria, must have an appropriate, preferably randomized, control group, and must be designed with sufficient power to evaluate the hypothesis.

Perspectives on cancer therapy-induced mucosal injury: pathogenesis, measurement, epidemiology, and consequences for patients

BACKGROUND

A frequent complication of anticancer treatment, oral and gastrointestinal (GI) mucositis, threatens the effectiveness of therapy because it leads to dose reductions, increases healthcare costs, and impairs patients' quality of life. The Multinational Association of Supportive Care in Cancer and the International Society for Oral Oncology assembled an international multidisciplinary panel of experts to create clinical practice guidelines for the prevention, evaluation, and treatment of mucositis.

METHODS

The panelists examined medical literature published from January 1966 through May 2002, presented their findings at two separate conferences, and then created a writing committee that produced two articles: the current study and another that codifies the clinical implications of the panel's findings in practice guidelines.

RESULTS

New evidence supports the view that oral mucositis is a complex process involving all the tissues and cellular elements of the mucosa. Other findings suggest that some aspects of mucositis risk may be determined genetically. GI proapoptotic and antiapoptotic gene levels change along the GI tract, perhaps explaining differences in the frequency with which mucositis occurs at different sites. Studies of mucositis incidence in clinical trials by quality and using meta-analysis techniques produced estimates of incidence that are presented herein for what to our knowledge may be a broader range of cancers than ever presented before.

CONCLUSIONS

Understanding the pathobiology of mucositis, its incidence, and scoring are essential for progress in research and care directed at this common side-effect of anticancer therapies.

New approaches to hematopoietic cell transplantation in oncology

The use of high-dose chemotherapy followed by autologous HCT and the use of allogeneic HCT in children and adolescents with high-risk ALL, AML, and NBL has successfully improved outcomes. For other diseases, however, the role of HCT in treatment remains a subject of further research. The availability of HCT was significantly expanded by developing alternative graft sources that currently include BM, peripheral blood, and UCB from autologous and allogeneic related or unrelated donors. Progress in autologous HCT has been achieved by the identification of more effective and less toxic preparative regimens and by ex vivo purging of stem cell products. In allogeneic HCT, graft-versus-leukemia or graft-versus-tumor effects are being exploited increasingly to lower relapse rates. In addition, immunomodulation to promote tolerance, as well as allogeneic antitumor reactions have been achieved by antibody therapy, cytokine therapy, or cell-based immunotherapy. Future improvements are likely, as evidenced by promising preliminary results in the development of stem cell collection techniques, in vitro stem cell expansion, and purging techniques of stem cell grafts. The development of less intensive or nonmyeloablative preparative regimens may further reduce regimen-related morbidity and mortality Specific immunotherapy may facilitate tolerance induction in mismatched allogeneic HCT and support allogeneic HCT in the setting of donor-host HLA disparity. Ultimately, advances in cytokine therapy, tumor-specific vaccines, and gene therapy may decrease or even eradicate recurrence of the malignant disease after HCT.

High-dose melphalan, etoposide, total-body irradiation, and autologous stem-cell reconstitution as consolidation therapy for high-risk Ewing's sarcoma does not improve prognosis

PURPOSE

To determine whether consolidation therapy with high-dose melphalan, etoposide, and total-body irradiation (TBI) with autologous stem-cell support would improve the prognosis for patients with newly diagnosed metastatic Ewing's sarcoma (ES).

PATIENTS AND METHODS

Thirty-two eligible patients with newly diagnosed ES metastatic to bone and/or bone marrow were enrolled onto this study. Treatment was initially comprised of five cycles of induction chemotherapy (cyclophosphamide, doxorubicin, and vincristine alternating with ifosfamide and etoposide) and local control. Peripheral-blood stem-cell collection was performed after the second cycle of chemotherapy, with delay if the bone marrow was persistently involved. If patients had a good response to initial therapy, they proceeded to consolidation therapy with melphalan, etoposide, TBI, and stem-cell support.

RESULTS

Of the 32 eligible patients, 23 proceeded to high-dose therapy consolidation. Of the nine patients who did not proceed to consolidation, four were secondary to progressive disease and two were secondary to toxicity. Three patients died from toxicity during the high-dose phase of the therapy. The majority of the patients who underwent high-dose consolidation therapy experienced relapse and died with progressive disease. Two-year event-free survival (EFS) for all eligible patients is 20%. The 2-year post-stem-cell reconstitution EFS for the subset of 23 patients who received consolidation therapy is 24%. Analysis of peripheral-blood stem-cell collections by molecular techniques for minimal residual disease showed contamination of at least some samples by tumor cells in all three patients with available data.

CONCLUSION

Consolidation with high-dose melphalan, etoposide, TBI, and autologous stem-cell support failed to improve the probability of EFS in this cohort of patients with newly diagnosed metastatic ES.

Role of high-dose chemotherapy with hematopoietic stem cell rescue in the treatment of metastatic or recurrent rhabdomyosarcoma

PURPOSE

This review summarizes the published data on the use of high-dose chemotherapy and hematopoietic stem cell rescue (HSCR) in the treatment of recurrent or metastatic rhabdomyosarcoma (RMS).

PATIENTS AND METHODS

Three hundred eighty-nine patients were identified from 22 articles selected by computer generated searching of MEDLINE (1979-present). One hundred seventy-seven patients had stage 4 disease and were treated during first complete remission (CRI). The remaining patients were treated during CR1/first partial remission (PR1) (110 patients), CR2/PR2 (53 patients), CR2 (12 patients), CR3 (1 patient), or treated with disease (36 patients).

RESULTS

Patients treated during CR1 or CR1/PR1 had event-free survival (EFS) rates ranging from 24% to 29% at 3 to 6 years from diagnosis and overall survival (OS) rates ranging from 20% to 40% at 2 to 6 years after diagnosis according to data provided as Kaplan-Meier estimates. Studies without Kaplan-Meier estimates (n = 32) indicate that 12 patients (38%) with stage IV RMS treated during CR1 or CR1/PR1 were surviving 7 to 60 months from diagnosis, similar to patients with stage IV RMS treated on Intergroup Rhabdomyosarcoma Studies II or III. Patients treated during CR2, CR3, or with evidence of disease had a worse outcome with an estimated 3 years OS of 12% (n = 51). Studies without Kaplan-Meier estimates (n = 27) indicate that four patients (15%) treated during CR2, CR3, or with disease were surviving 17 to 33 months after transplant.

CONCLUSIONS

Based on these data, there does not appear to be a significant advantage to undergoing high-dose chemotherapy with HSCR for patients with relapsed or refractory high-risk RMS. Clearly, there is a need for incorporating new treatment strategies for patients with high-risk RMS.

Progress in the diagnosis and treatment of rhabdomyosarcoma and related soft tissue sarcomas

Advances in the diagnosis and treatment of rhabdomyosarcoma and related soft tissue sarcomas continue in the Intergroup Rhabdomyosarcoma Study Group (IRSG) and European cooperative groups. The use of molecular biology techniques in soft tissue sarcomas are redefining the classic pathology of these small blue cell tumors. Improvements in imaging, radiotherapy, and surgery, in part, deserve credit for the better survival seen in all cooperative trials. These advances confound the interpretation of consecutively run chemotherapy trials using historical comparisons. The IRSG has reported improvement in the prognosis of both nonmetastatic and metastatic embryonal rhabdomyosarcoma as attributable to three, three-drug regimens that use cyclophosphamide at 2.2 g/m2 in either maintenance or induction and maintenance therapy. Patients of any age with metastatic, nonembryonal, and those over 10 years of age with metastatic embryonal rhabdomyosarcoma continue to have a poor prognosis, which even megatherapy has failed to change. The doublet of ifosfamide and etoposide in combination with vincristine, actinomycin D, and cyclophosphamide at 2.2 g/m2 achieved a remarkable 3-year survival of 58% in patients with metastatic rhabdomyosarcoma and undifferentiated soft tissue sarcoma. The topoisomerase I inhibitor, topotecan, has recently been found by the IRSG to have a 57% overall response rate in patients with metastatic alveolar rhabdomyosarcoma. Topotecan has completed testing with cyclophosphamide in a phase II window study in newly diagnosed patients with metastatic disease and has been incorporated into a randomized trial in intermediate risk patients in IRSG-V. Molecular studies in IRSG-V will be applied in the detection of occult bone marrow metastases and the evaluation of resection margins at initial and second-look surgery. Long-term follow-up will be required in patients with gross residual sarcoma randomized to conventional and hyperfractionated radiotherapy in IRSG-IV to assess late effects. Although older patients with unfavorable histology and metastatic disease continue to have a poor prognosis, the overall 5-year survival of children and adolescents with nonmetastatic and metastatic rhabdomyosarcoma is approaching 80%. As molecular discoveries advance the diagnosis and detection of rhabdomyosarcoma, it is hoped that the futuristic molecular based treatment strategies in development and early testing will further improve survival in high-risk patients with metastatic soft tissue sarcoma.

How effective is dose-intensive/myeloablative therapy against Ewing's sarcoma/primitive neuroectodermal tumor metastatic to bone or bone marrow? The Memorial Sloan-Kettering experience and a literature review

PURPOSE

Attempts to improve outcomes of patients with Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) metastatic to bone/bone marrow (BM) have focused on chemotherapy dose intensification strategies. We now present results achieved with that approach, as carried out at Memorial Sloan-Kettering Cancer Center (MSKCC) and as reported in the literature.

PATIENTS AND METHODS

Twenty-one unselected MSKCC patients with newly diagnosed ES/PNET metastatic to bone/BM received the "P6" protocol which includes cycles of cyclophosphamide (4.2 g/m(2))/doxorubicin (75 mg/m(2))/vincristine and cycles of ifosfamide (9 g/m(2))/etoposide (500 mg/m(2)). Patients in complete/very good partial remission (CR/VGPR) after P6 received myeloablative therapy with either total-body irradiation (TBI) (hyperfractionated 15 Gy)/melphalan (180 mg/m(2)) or thiotepa (900 mg/m(2))/carboplatin (1,500 mg/m(2)). We reviewed the literature.

RESULTS

Only one MSKCC patient became a long-term event-free survivor; all but one relapse was in a distant site. Initial responses to P6 were CR/VGPR in 19 patients, but eight of them plus two others developed PD while receiving or shortly after completing P6. Eight patients were treated with TBI/melphalan: four relapsed 2 to 7 months after transplantation; two died early of toxicity; one died of pulmonary failure 17 months after transplantation (no evidence of ES/PNET); and one remains in CR at more than 7 years. The three patients treated with thiotepa/carboplatin relapsed 3 to 4 months after transplantation. All reports on large series of unselected patients with ES/PNET metastatic to bone/BM showed similarly unsatisfactory results. Poor outcome was seen with use of active agents for ES/PNET-cyclophosphamide, ifosfamide, doxorubicin, dactinomycin, vincristine, etoposide - at standard dosages for prolonged periods of time and at higher dosages in intensive regimens for short or prolonged periods of time. No improvements in event-free survival rates occurred with successive cooperative group or large single-institutional studies that used increasingly aggressive chemotherapeutic approaches. Inclusion of ifosfamide with or without etoposide made no difference nor did consolidation of remission with myeloablative chemoradiotherapy. Secondary leukemia emerged as a major risk with dose-intensive regimens.

CONCLUSION

The MSKCC experience and findings reported in the literature suggest that dose-intensive use of the chemotherapy agents with established activity against ES/PNET is reaching its efficacy and toxicity limits. A major impact on prognosis awaits the development of entirely novel therapies.

Selective use of whole-lung irradiation for patients with Ewing sarcoma family tumors and pulmonary metastases at the time of diagnosis

PURPOSE

The benefit of whole-lung irradiation (WLI) for patients who have pulmonary metastases (PM) of Ewing sarcoma family tumors (ESFT) is unclear. At our institution, WLI is reserved for patients with PM that do not respond completely to induction chemotherapy. We reviewed our experience to assess the impact of WLI on clinical outcome.

PATIENTS AND METHODS

Twenty-eight patients with ESFT and PM were treated in three consecutive institutional trials (1979-1996). Extent of pulmonary involvement at diagnosis, response of PM after induction chemotherapy, local treatment of PM thereafter, and clinical outcome were recorded. Treatment included primary tumor surgery and/or radiotherapy and 42 to 58 weeks of multiagent chemotherapy.

RESULTS

Only eight patients (29%) received WLI. For the entire study group, the estimated 5-year event-free survival was 22.9% +/- 9.0%; the 5-year survival was 37.3% +/- 9.8%. Complete resolution of PM after induction chemotherapy was not correlated with survival (P = 0.53), nor was treatment with WLI (P = 0.87).

CONCLUSIONS

The comparable survival of patients with poor and good response of PM to induction chemotherapy suggests that WLI may benefit poor responders. The use of WLI in good responders may provide similar benefit and merits further study.

Allograft with unrelated donor accentuates the gastrointestinal toxicity associated with high-dose melphalan and total body irradiation preparative for bone marrow transplantation in children

The use of high-dose melphalan (L-phenyalalanine mustard or L-PAM) has been shown to be associated with both hematological and non-hematological toxicity. It has been employed in the conditioning for allogeneic stem cell transplants from related donors but experience on its use in the unrelated setting has not been reported. As an attempt to elucidate the role of high-dose L-PAM (210 mg/m2) and total body irradiation (TBI) as a preparative regimen for allogeneic marrow transplantation from matched unrelated donors, they were employed in an institutional pilot series of seven pediatric patients. When compared with recipients of unrelated marrow grafts conditioned using other regimens, those treated with high-dose L-PAM experienced a markedly more severe acute graft-vs.-host disease (GvHD). The overall incidence of grade III-IV acute GvHD was higher (86% vs. 14%) among those treated with L-PAM. As judged by gastrointestinal (GI) symptoms, clinically significant (stages +2 to +4) gut GvHD was strikingly more prevalent among those treated with L-PAM (86% vs. 9%, p < 0.005). Toxic mortality prior to day + 100 was 29% in the L-PAM group and 9% in the non-L-PAM group of patients. With a mean follow-up of 21 months no increase in the incidence of chronic GvHD has been encountered among those conditioned with L-PAM. We conclude that the use of preparative L-PAM for allogeneic transplants from unrelated donors is associated with considerable procedure-related toxicity. We strongly suggest its use in this setting to be viewed with caution.

High-dose melphalan with autologous stem-cell rescue in metastatic rhabdomyosarcoma

PURPOSE

The European Collaborative MMT4-91 trial was conducted as a prospective nonrandomized study to evaluate the potential benefit of high-dose melphalan as consolidation of first complete remission in children with stage IV rhabdomyosarcoma.

PATIENTS AND METHODS

Fifty-two patients in complete remission after six courses of chemotherapy received "megatherapy": 42 received melphalan alone, whereas 10 received melphalan in combination with etoposide, carboplatin/etoposide, or thiotepa/busulfan and etoposide. The outcome of this group of patients was compared with that observed in 44 patients who were also in complete remission after six courses of identical chemotherapy (plus surgery or radiotherapy) but went on to receive a total of up to 12 courses of conventional chemotherapy (four cycles). No differences were found between the two groups regarding clinical characteristics, chemotherapy received before complete remission, or response to chemotherapy. In particular, there was no significant difference between the groups for site of primary tumor, histologic subtype, age at presentation, presence of bone or bone marrow metastases, or number of metastases.

RESULTS

The 3-year event-free survival (EFS) and overall survival (OS) rates were 29.7% and 40%, respectively, for those receiving high-dose melphalan or other multiagent high-dose regimens and 19.2% and 27.7%, respectively, for those receiving standard chemotherapy. The difference was not statistically significant (P =.3 and P =.2 for EFS and OS, respectively). There was a significant prolongation in the time from the last day of high-dose chemotherapy or the end of chemotherapy cycle 4 to the time of relapse in those receiving megatherapy (168 days for patients receiving megatherapy v 104 days for those receiving standard therapy; P =.05).

CONCLUSION

The addition of a high-dose alkylating agent to consolidation therapy may have prolonged progression-free survival in this poor-risk patient group, but it did not significantly improve the ultimate outcome.