Patient-derived xenografts effectively capture responses to oncology therapy in a heterogeneous cohort of patients with solid tumors.

BACKGROUND: While patient-derived xenografts (PDXs) offer a powerful modality for translational cancer research, a precise evaluation of how accurately patient responses correlate with matching PDXs in a large, heterogeneous population is needed for assessing the utility of this platform for preclinical drug-testing and personalized patient cancer treatment. PATIENTS AND METHODS: Tumors obtained from surgical or biopsy procedures from 237 cancer patients with a variety of solid tumors were implanted into immunodeficient mice and whole-exome sequencing was carried out. For 92 patients, responses to anticancer therapies were compared with that of their corresponding PDX models. RESULTS: We compared whole-exome sequencing of 237 PDX models with equivalent information in The Cancer Genome Atlas database, demonstrating that tumorgrafts faithfully conserve genetic patterns of the primary tumors. We next screened PDXs established for 92 patients with various solid cancers against the same 129 treatments that were administered clinically and correlated patient outcomes with the responses in corresponding models. Our analysis demonstrates that PDXs accurately replicate patients' clinical outcomes, even as patients undergo several additional cycles of therapy over time, indicating the capacity of these models to correctly guide an oncologist to treatments that are most likely to be of clinical benefit. CONCLUSIONS: Integration of PDX models as a preclinical platform for assessment of drug efficacy may allow a higher success-rate in critical end points of clinical benefit.

A case report of concurrent embryonal rhabdomyosarcoma and diffuse large B-cell lymphoma in an adult without identifiable cancer predisposition.

BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin lymphoma. Rhabdomyosarcoma, the most common soft tissue sarcoma of childhood. makes up less than 1% of solid malignancies in adults with around 400 new cases each year in the United States. They have not previously been reported concurrently. CASE PRESENTATION: A 37 year old woman presented with painful enlarging leg mass. Biopsy of the mass was consistent with embryonal rhabdomyosarcoma. Staging imaging revealed a PET avid anterior mediastinal lymph node. Excisional biopsy of this mass was consistent with diffuse large B-cell lymphoma. Hybridization capture-based next-generation DNA sequencing did not reveal shared somatic tumor mutations. Germline analysis did not show identifiable aberrations of TP53 or other heritable cancer susceptibility genes. She was treated with a personalized chemotherapy regimen combining features of R-CHOP and Children's Oncology Group ARST 0331. CONCLUSIONS: This case illustrates a unique clinical entity successfully treated with a personalized chemotherapeutic regimen.

Insulin-like growth factor type 1 (IGF-1) and IGF binding protein-3 in patients with Ewing sarcoma family of tumors.

BACKGROUND: Ewing sarcoma family of tumors (ESFTs) are the second most common bone tumor, that most often affects persons ages 3-40 years. The ESFTs rely on signaling through the insulin-like growth factor-1 receptor (IGF-1R) for growth and transformation. The current studies were performed to determine the levels of IGF-1 and IGF binding protein-3 (IGFBP-3) in patients with ESFT. The authors then performed an exploratory analysis to evaluate whether IGF parameters could differentiate event free or overall survival in ESFT patients. METHODS: The authors measured serum levels of IGF-1 and IGFBP-3 by using a radioimmunoassay from 111 patients with ESFT with a median follow-up of 13 years from diagnosis. RESULTS: The IGF-1 levels were lower among patients with metastatic disease to the bones or the bone marrow compared with patients without metastasis to these sites (p2 = 0.021 and 0.0038, respectively). IGFBP-3 is known to sequester IGF-1; the ratios of IGFBP-3 to IGF-1 were evaluated. Patients with metastatic disease to any site had higher IGFBP-3 to IGF-1 ratios than patients with localized disease (p2 = 0.0067). There was a trend toward increased survival in patients with localized disease who had high IGFBP-3 to IGF-1 levels. Metastatic patients showed a similar trend. CONCLUSIONS: Levels of IGF-1 and IGFBP-3 in ESFT patients can identify patients with the most widespread disease. The IGFBP-3 to IGF-1 ratio in patients with either localized or metastatic disease identified patients with a trend toward increased survival. Further prospective evaluation with higher patient numbers might show a prognostic role for the IGFBP-3 to IGF-1 ratio in patients with ESFT.

Lack of correlation of functional scintigraphy with (99m)technetium-methoxyisobutylisonitrile with histological necrosis following induction chemotherapy or measures of P-glycoprotein expression in high-grade osteosarcoma.

In osteosarcoma, some studies have suggested P-glycoprotein expression is a prognostic factor. The clearance of (99m)technetium hexakis-2-methoxyisobutylisonitrile ((99m)Tc-MIBI) has been used in some tumor systems as an in vivo measure of P-glycoprotein-mediated efflux. In this study we explored the correlation between (99m)Tc-MIBI clearance and histological necrosis following induction chemotherapy and P-glycoprotein expression in osteosarcoma. The primary tumors of 20 patients with high-grade osteosarcoma were imaged at diagnosis with (99m)Tc-MIBI, and the uptake ratios and biological half-lives were calculated. P-Glycoprotein expression in the tumor tissue was determined immunohistochemically and by measuring mRNA expression of the multidrug resistance-1 gene. The histological necrosis following induction chemotherapy was assessed by the Huvos grading system. The biological half-life of (99m)Tc-MIBI ranged from 1.4 to 52.5 h. Seven of the 20 tumor samples had a favorable extent of necrosis following induction chemotherapy. The (99m)Tc-MIBI half-life and uptake ratio showed no correlation with histological necrosis following induction chemotherapy. The (99m)Tc-MIBI half-life and uptake ratio did not correlate with either measure of P-glycoprotein expression. The results of this pilot study indicate that (99m)Tc-MIBI imaging is not an effective predictor of histological necrosis following induction chemotherapy in high-grade osteosarcoma. (99m)Tc-MIBI imaging did not correlate with measures of P-glycoprotein expression in the tumor tissue.

Prolonged CD4 depletion after sequential autologous peripheral blood progenitor cell infusions in children and young adults.

Administration of mobilized peripheral blood progenitor cells (PBPCs) after high-dose chemotherapy rapidly restores multilineage hematopoiesis, but the ability of such products to restore lymphocyte populations remains unclear. In this report, we evaluated immune reconstitution in a series of patients treated with sequential cycles of high-dose chemotherapy, followed by autologous PBPC infusions (median CD34(+) cell dose 7.2 x 10(6) cells/kg [range 2-29.3]). Although patients experienced rapid reconstitution of B cells and CD8(+) T cells, we observed CD4 depletion and diminished immune responsiveness in all patients for several months after completion of therapy. Mature CD4(+) T cells contained within the grafts did not appear to contribute substantially to immune reconstitution because CD4 counts did not differ between recipients of unmanipulated T-cell replete infusions versus CD34 selected, T-cell-depleted infusions. Rather, at 12 months after therapy, total CD4 count was inversely proportional to age (rho = -0.78, P =.04), but showed no relationship to CD34 cell dose (rho = -0.42, P =.26), suggesting that age-related changes within the host are largely responsible for the limited immune reconstitution observed. These results demonstrate that in the autologous setting, the infusion of large numbers of PBPCs is not sufficient to restore T-cell immune competence and emphasize that specific approaches to enhance immune reconstitution are necessary if immune-based therapy is to be used to eradicate minimal residual disease after autologous PBPC transplantation. (Blood. 2000;96:754-762)

EWS-FLI1 and EWS-ERG gene fusions are associated with similar clinical phenotypes in Ewing's sarcoma.

PURPOSE: There are a variety of solid tumors in which alternative chromosomal translocations generate related fusion products. In alveolar rhabdomyosarcoma and synovial sarcoma, these variant fusions have been found to have major clinical significance. We investigated whether the two alternative gene fusion products, EWS-FLI1 and EWS-ERG, define different clinical subsets within the Ewing's sarcoma family of tumors. PATIENTS AND METHODS: We selected 30 cases of Ewing's sarcoma with the EWS-ERG gene fusion and 106 cases with the EWS-FLI1 fusion. Clinical data were obtained for each case and compared with the molecular diagnostic findings. RESULTS: There were no significant clinical differences observed between the two groups in age of diagnosis, sex, metastasis at diagnosis, primary site, event-free survival, or overall survival. CONCLUSION: Differences in the C-terminal partner in the Ewing's sarcoma family gene fusions are not associated with significant phenotypic differences.

Neuroectodermal differentiation in Ewing's sarcoma family of tumors does not predict tumor behavior.

The observation that neuroectodermal differentiation imparts a worse prognosis to the Ewing family of tumors has been suggested by some studies and refuted by others. To assess whether the diagnosis of Ewing's sarcoma versus peripheral primitive neuroectodermal tumor (PNET) affects prognosis, we analyzed tumors from 63 analogously treated pediatric and young adult patients from the National Cancer Institute and St Jude Children's Research Hospital and retrospectively compared the results with clinical outcomes. The tumors were assessed using standard light microscopy and immunohistochemical stains for neuron-specific enolase, CD57, S100 protein, neurofilament protein, and synaptophysin with or without antigen retrieval. Ultrastructural evaluation was also performed in 39 tumors. Classification was performed using Kiel criteria as well as a modified classification. Kaplan-Meier analyses, with Mantel-Haenzel evaluation of the significance of the differences, were performed separately for localized or metastatic tumors. Using the Kiel classification on a subset of 60 cases, 39 tumors qualified as PNET and 21 as Ewing's sarcoma. Using the modified classification on a subset of 61 cases, 14 were classified as PNET, 21 as atypical Ewing's sarcoma, and 26 as Ewing's sarcoma. The addition of electron microscopy to the diagnostic armamentarium significantly increased the likelihood of identifying PNET. No significant differences in event-free or overall survival were seen using either the modified or Kiel classification, regardless of the ancillary diagnostic techniques employed. In this exploratory analysis, neuroectodermal differentiation did not play a role in clinical outcome. Confirmation of this finding will require a larger, separate study of similarly treated patients, and it may not apply to older patients.

Ameliorating anthracycline cardiotoxicity in children with cancer: clinical trials with dexrazoxane.

Anthracyclines have major activity against a broad range of childhood cancers. Concern over the risk of long-term cardiotoxicity associated with their use has called into question the role of these agents in the frontline treatment of many patients. Dexrazoxane was developed as a specific cardioprotectant "antidote" which can prevent anthracycline cardiotoxicity without inhibiting its antitumor effect. To date, four clinical trials of dexrazoxane have been conducted in pediatric cancer patients (primarily with sarcomas). The two largest series, conducted at the National Cancer Institute Pediatric Branch, demonstrated significant short-term cardioprotection with no evidence of interference with antitumor activity. Additional clinical trials are ongoing, or planned to open shortly, to better evaluate the role of dexrazoxane in the treatment of childhood cancer. These studies, being conducted on larger numbers of patients with better prospects for cure, are expected to definitviely answer the outstanding questions of whether preventing short-term, subclinical cardiotoxicity will translate into long-term cardioprotection, and whether the use of dexrazoxane interferes with the anti-tumor efficacy of doxorubicin-containing regimens.

Reoperative pulmonary metastasectomy for sarcomatous pediatric histologies.

BACKGROUND: The role for reoperative pulmonary metastasectomy in patients with "pediatric sarcomas" (osteosarcoma, nonrhabdomyosarcoma-soft tissue sarcoma, and Ewing's sarcoma) is undefined. METHODS: We reviewed our results for patients with these histologic presentations (median age, 17.5 years; range, 6 to 32 years) having two (70), three (27), or four (10) metastasectomies between January 1965 and March 1995 to define postresection survival and potential prognostic factors. Simple wedges (88 thoracotomies, 84%) were performed more frequently than anatomic (17 thoracotomies, 16%) resections. RESULTS: With a median potential follow-up of 12.7 years, median survival was 2.25, 3.60, and 0.96 years from the second, third, and fourth explorations, respectively. Primary tumor site, sex, histology, age, maximal metastasis size, and systemic chemotherapy did not influence survival. Resectability was the most important prognostic factor (5.6 versus 0.7 years, 5.2 versus 2.5 years, 2.2 versus 0.2 years, resectable versus unresectable, median survival from second, third, and fourth thoracotomy, respectively). Unresectability, disease-free interval less than 6 months between initial (ie, first) pulmonary resection and the second thoracotomy, and two or more preoperative nodules noted on the right were simultaneously negatively associated with survival from the second thoracotomy. Unresectability or finding two or more metastases negatively affected survival from the third thoracotomy. CONCLUSIONS: These data imply that repeat metastasectomy can salvage a subset of patients with sarcomatous pediatric histologic presentations who retain favorable prognostic determinants.

Sciatic nerve: paradoxic hypertrophy after amputation in young patients.

PURPOSE: To evaluate the appearance of the sciatic nerve after leg amputation. MATERIALS AND METHODS: Magnetic resonance (MR) images were obtained in seven patients (age at amputation, 11-19 years) who underwent above-knee amputation to treat osteogenic sarcoma. Images were evaluated for sciatic nerve enlargement. Findings were correlated with the time after amputation. RESULTS: All seven patients were found to have a markedly enlarged sciatic nerve in the stump of the amputated leg. The enlargement extended proximally from the point of nerve transection to a level posterior to the femoral neck (8-27 cm) depending on the length of the stump. No evidence of sciatic nerve enlargement was found in the opposite leg or on preoperative MR images that were available in three of the patients. Moreover, in one patient with a sarcoma who underwent a leg-sparing procedure, no sciatic nerve enlargement was seen postoperatively. The thickness of the distal sciatic nerve was related to the time after amputation. CONCLUSION: Hypertrophy of the sciatic nerve occurred after above-knee amputation in young patients. This finding differed from atrophy of the nerve that has been reported previously in older patients.

Distinctions between CD8+ and CD4+ T-cell regenerative pathways result in prolonged T-cell subset imbalance after intensive chemotherapy.

Rapid recovery of CD4+ T cells after intensive chemotherapy is limited by an age-dependent decline in thymopoiesis. Here we sought to determine whether similar limitations exist for CD8+ T-cell regeneration. After intensive chemotherapy, CD8+ T cells had a faster effective doubling time than CD4+ T cells (median, 12.6 v 28.2 days, P < .05). Accordingly, at 3 months posttherapy, mean CD8+ T-cell number had returned to baseline, whereas mean CD4+ T-cell number was only 35% of pretherapy values (P < .05). These differences were primarily due to very rapid expansion of CD8+CD57+ and CD8+CD28- subsets. At 3 months posttherapy, there was no relationship between age and CD8+ T-cell number (R = -.02), whereas CD4+ T-cell number was inversely related to age (R = -.66) and there were no discernible differences in CD8+ recovery among patients with or without thymic enlargement, whereas CD4+ recovery was enhanced in patients with thymic enlargement after chemotherapy (P < .01). Therefore thymic-independent pathways of T-cell regeneration appear to rapidly regenerate substantial numbers of CD8+, but not CD4+ T cells, resulting in prolonged T-cell subset imbalance after T-cell depletion. These inherent distinctions between CD4+ v CD8+ T-cell regeneration may have significant implications for immunotherapeutic strategies undertaken to eradicate minimal residual neoplastic disease after cytoreductive chemotherapy.

Late effects of therapy in survivors of Ewing's sarcoma family tumors.

PURPOSE: This late effects study was designed to determine if survivors of Ewing's sarcoma family tumors (ESFT) had adverse outcomes in employment, marital status, fertility, and functional status when compared to sibling controls. SUBJECTS AND METHODS: Eighty-nine survivors (case subjects) of ESFT treated at the National Cancer Institute between 1965 and 1992 and 97 sibling controls completed a questionnaire probing aspects of quality of life. The answers from case subjects were compared to pooled and matched sibling controls for all key variables. Odds ratios (OR) and p values from pooled analyses are presented. RESULTS: Although case subjects and controls did not differ in educational achievement, case subjects were less likely to be employed full-time (OR 0.4, p < 0.01), to be married (OR 0.2, p < 0.01), and to have children (OR 0.3, p < 0.01). Their most common treatment-related difficulties included permanent hair and skin changes (43%), lung problems (18%), neurologic problems (14%), visual difficulties (10%), second malignancy (7%), and amputation (5%). Functional status, measured by Karnofsky performance scale, was also adversely affected in case subjects. Case subjects did not differ from sibling controls in health care insurance status or in utilization of health services. CONCLUSIONS: Important aspects of life such as employment, marital status, fertility, and functional status are affected in survivors of ESFT. More studies are needed to better define the health status of adult survivors of pediatric cancer and the impact of cancer in adolescence on psychosocial development.

Nevoid basal cell carcinoma syndrome with medulloblastoma in an African-American boy: a rare case illustrating gene-environment interaction.

We present an 8-year-old African-American boy with medulloblastoma and nevoid basal cell carcinoma syndrome (NBCCS) who exhibited the radiosensitive response of basal cell carcinoma (BCC) formation in the area irradiated for medulloblastoma. Such a response is well-documented in Caucasian NBCCS patients with medulloblastoma. The propositus was diagnosed with medulloblastoma at the age of 2 years and underwent surgery, chemotherapy, and craniospinal irradiation. At the age of 6 years, he was diagnosed with NBCCS following his presentation with a large odontogenic keratocyst of the mandible, pits of the palms and soles and numerous BCCs in the area of the back and neck that had been irradiated previously for medulloblastoma. Examination of other relatives showed that the propositus' mother also had NBCCS but was more mildly affected; in particular, she had no BCCs. This case illustrates complex gene-environment interaction, in that increased skin pigmentation in African-Americans is presumably protective against ultraviolet, but not ionizing, radiation. This case and other similar cases in the literature show the importance of considering NBCCS in the differential diagnosis of any patient who presents with a medulloblastoma, especially before the age of 5 years, and of examining other close relatives for signs of NBCCS to determine the patient's at-risk status. Finally, for individuals who are radiosensitive, protocols that utilize chemotherapy in lieu of radiotherapy should be considered.

Second malignancies after Ewing's sarcoma: radiation dose-dependency of secondary sarcomas.

BACKGROUND: An excess risk of second malignancies has been reported in survivors of Ewing's sarcoma. We examined a multiinstitutional data base to reevaluate the risk among survivors of Ewing's sarcoma and to identify possible causal factors. METHODS: Information was derived from a data base that included 266 survivors of Ewing's sarcoma. Cumulative incidence rates of second malignancies were calculated. Contributions of clinical features, type and dose of chemotherapy, and cumulative radiation dose to the risk of second malignancies were evaluated. RESULTS: After a median follow-up duration of 9.5 years (range, 3.0 to 30), 16 patients have developed second malignancies, which included 10 sarcomas (five osteosarcomas, three fibrosarcomas, and two malignant fibrous histiocytomas) and six other malignancies (acute myeloblastic leukemia, acute lymphoblastic leukemia, meningioma, bronchioalveolar carcinoma, basal cell carcinoma, and carcinoma-in-situ of the cervix). The median latency to the diagnosis of the second malignancy was 7.6 years (range, 3.5 to 25.7). The estimated cumulative incidence rates at 20 years for any second malignancy and for secondary sarcoma were 9.2% (SD = 2.7%) and 6.5% (SD = 2.4%), respectively. The cumulative incidence rate of secondary sarcoma was radiation dose-dependent (P = .002). No secondary sarcomas developed among patients who had received less than 48 Gy, while the absolute risk of secondary sarcoma was 130 cases per 10,000 person-years of observation among patients who had received > or = 60 Gy. CONCLUSION: The overall risk of second malignancies after Ewing's sarcomas is similar to that associated with treatment for other childhood cancers. The radiation dose-dependency of secondary sarcomas justifies modification in therapy to reduce radiation doses.

Ifosfamide and etoposide plus vincristine, doxorubicin, and cyclophosphamide for newly diagnosed Ewing's sarcoma family of tumors.

BACKGROUND: This study was conducted to determine the feasibility of, and improve outcome by, incorporating ifosfamide and etoposide (IE) into the therapy of newly diagnosed patients with Ewing's sarcoma family of tumors of bone and soft tissue. METHODS: Fifty-four newly diagnosed patients received 7 cycles of vincristine, doxorubicin, and cyclophosphamide (VAdriaC) and 11 cycles of IE. Radiation therapy after the fifth chemotherapy cycle was the primary approach to local control. RESULTS: Actuarial 5-year event-free survival (EFS) and overall survival rates were 42% and 45%, respectively, with a median duration of potential follow-up of 6.8 years. EFS was significantly better for patients with localized tumors than for those with metastatic lesions (64% v. 13%, P < 0.0001). Actuarial local progression-free survival at 5 years was 74%, and did not correlate with primary tumor size or site, histologic subtype, or the presence of metastases. Febrile neutropenia developed after 49% of cycles, and clinical or sub-clinical cardiac dysfunction was common (7% and 40% respectively). There were four toxic deaths and one case of secondary myelodysplastic syndrome. CONCLUSIONS: Despite substantial toxicity, the integration of IE into the front-line, VAdriaC-based therapy of patients with Ewing's sarcoma family of tumors is feasible and appeared to significantly improve the outcome for patients with high risk localized tumors, but had no impact on the poor prognosis of patients with metastatic tumors. Local control can be achieved in the vast majority of patients using radiotherapy exclusively, even among patients with bulky, central axis tumors. Longer follow-up is needed to evaluate the late effects of this intensive therapy.

Randomized trial of recombinant human granulocyte-macrophage colony-stimulating factor in pediatric patients receiving intensive myelosuppressive chemotherapy.

PURPOSE: To evaluate whether recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) reduces the hematologic toxicities and supportive care requirements of an intensive combination chemoradiotherapy regimen in pediatric and young adult sarcoma patients. PATIENTS AND METHODS: Thirty-seven newly diagnosed patients age 1 to 25 years were randomized to receive 18 cycles of chemotherapy alone or with GM-CSF beginning in cycle 3. GM-CSF (5 to 15 micrograms/kg/d subcutaneously) was begun 24 hours after the completion of chemotherapy and continued through day 19 of each cycle or until the absolute granulocyte count (AGC) was > or = 500/microliter on 2 consecutive days. RESULTS: GM-CSF reduced the median duration of grade 4 granulocytopenia from 9.0 days (range, 2 to 24) to 7.0 days (range, 1 to 21) (P < .0001), but did not significantly affect the grade of granulocyte nadir. No differences were seen in the incidence or types of infectious complications, incidence or duration of hospitalization and antimicrobial therapy, response to chemotherapy, or event-free or overall survival. GM-CSF was associated with more severe and protracted thrombocytopenia (median platelet nadir, 29,500/microliter [range, 3,000 to 288,000] v 59,000/microliter [range, 3,000 to 309,000], P < .0001; median time to recovery > 75,000/microliter, 16.0 days [range, 0 to 61] v 14.0 days [range, 0 to 38], P < .0001). CONCLUSION: GM-CSF does not produce clinically meaningful reductions in the degree or duration of severe granulocytopenia following intensive multiagent chemotherapy, but is associated with worsened thrombocytopenia. GM-CSF also does not reduce the need for hospitalization or the incidence of febrile neutropenia and infectious complications. We conclude that the costs and increased toxicities associated with the use of this agent are not justified by its minimal clinical benefit for regimens of this level of intensity.

Experiences of cancer in children and adolescents.

In an effort to understand the effect of cancer diagnosis and treatment in children and adolescents, and to identify issues that should be addressed with newly diagnosed patients, 85 patients with Ewing's sarcoma family tumors (ESFT) were interviewed about their experience of having cancer. This represents 90% of all eligible patients who survived at least 3 years since their diagnosis and who were treated for ESFT at the National Cancer Institute (NCI) from 1965-1993. The mean age of patients at the time of diagnosis was 15.8 +/- 5.3 years, and mean time since diagnosis was 13.6 +/- 6.4 years. Patients from this cohort had a disease usually related to poor outcome. Patients answered five open-ended written questions. Negative experiences that they described included transient and permanent discomfort and disabilities related to cancer; disruption of life or relationships; and emotional aspects of cancer diagnosis or treatment. Positive aspects of having cancer included changed attitudes about self and life, improved relationships with others, or better job performance. Advice for newly diagnosed patients most often dealt with the emotional aspects of cancer. The importance of patient-to-patient support was frequently described. Overall, having cancer was not an entirely negative experience, and it may result in introspection and improved relationships with others.

Randomized trial of the cardioprotective agent ICRF-187 in pediatric sarcoma patients treated with doxorubicin.

PURPOSE: We conducted an open-label, randomized trial to determine whether ICRF-187 would reduce doxorubicin-induced cardiotoxicity in pediatric sarcoma patients. METHODS: Thirty-eight patients were randomized to receive doxorubicin-containing chemotherapy (given as an intravenous bolus) with or without ICRF-187. Resting left ventricular ejection fraction (LVEF) was monitored serially with multigated radionuclide angiography (MUGA) scan. The two groups were compared for incidence and degree of cardiotoxicity, response rates to four cycles of chemotherapy, event-free and overall survival, and incidence and severity of noncardiac toxicities. RESULTS: Eighteen ICRF-187-treated and 15 control patients were assessable for cardiac toxicity. ICRF-187-treated patients were less likely to develop subclinical cardiotoxicity (22% v 67%, P < .01), had a smaller decline in LVEF per 100 mg/m2 of doxorubicin (1.0 v 2.7 percentage points, P = .02), and received a higher median cumulative dose of doxorubicin (410 v 310 mg/m2, P < .05) than did control patients. Objective response rates were identical in the two groups, with no significant differences seen in event-free or overall survival. ICRF-187-treated patients had a significantly higher incidence of transient grade 1 serum transaminase elevations and a trend toward increased hematologic toxicity. CONCLUSION: ICRF-187 reduces the risk of developing short-term subclinical cardiotoxicity in pediatric sarcoma patients who receive up to 410 mg/m2 of doxorubicin. Response rates to chemotherapy, event-free and overall survival, and noncardiac toxicities appear to be unaffected by the use of ICRF-187. Additional clinical trials with larger numbers of patients are needed to determine if the short-term cardioprotection afforded by ICRF-187 will reduce the incidence of late cardiac complications in long-term survivors of childhood cancer.