Catherine A. Poquette

Direct Translation of a Protracted Irinotecan Schedule From a Xenograft Model to a Phase I Trial in Children

PURPOSE In a preclinical model of neuroblastoma, administration of irinotecan daily 5 days per week for 2 consecutive weeks ([qd x 5] x 2) resulted in greater antitumor activity than did a single 5-day course with the same total dose. We evaluated this protracted schedule in children. PATIENTS AND METHODS Twenty-three children with refractory solid tumors were enrolled onto a phase I study. Cohorts received irinotecan by 1-hour intravenous infusion at 20, 24, or 29 mg/m(2) (qd x 5) x 2 every 21 days. RESULTS The 23 children (median age, 14.1 years; median prior regimens, two) received 84 courses. Predominant diagnoses were neuroblastoma (n = 5), osteosarcoma (n = 5), and rhabdomyosarcoma (n = 4). The dose-limiting toxicity was grade 3/4 diarrhea and/or abdominal cramps in six of 12 patients treated at 24 mg/m(2), despite aggressive use of loperamide. The maximum-tolerated dose (MTD) on this schedule was 20 mg/m(2)/d. Five patients had partial responses and 16 had disease stabilization. On day 1, the median systemic exposure to SN-38 (the active metabolite of irinotecan) at the MTD was 106 ng-h/mL (range, 41 to 421 ng-h/mL). CONCLUSION This protracted schedule is well tolerated in children. The absence of significant myelosuppression and encouraging clinical responses suggest compellingly that irinotecan be further evaluated in children using the (qd x 5) x 2 schedule, beginning at a dose of 20 mg/m(2). These results imply that data obtained from xenograft models can be effectively integrated into the design of clinical trials.

Prognostic Factors for Children and Adolescents With Surgically Resected Nonrhabdomyosarcoma Soft Tissue Sarcoma: An Analysis of 121 Patients Treated at St Jude Children's Research Hospital

PURPOSE The rarity and heterogeneity of pediatric nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) has precluded meaningful analysis of prognostic factors associated with surgically resected disease. To define a population of patients at high risk of treatment failure who might benefit from adjuvant therapies, we evaluated the relationship between various clinicopathologic factors and clinical outcome of children and adolescents with resected NRSTS over a 27-year period at our institution. PATIENTS AND METHODS We analyzed the records of 121 consecutive patients with NRSTS who underwent surgical resection between August 1969 and December 1996. Demographic data, tumor characteristics, treatment, and outcomes were recorded. Univariate and multivariate analyses of prognostic factors for survival, event-free survival (EFS), and local and distant recurrence were performed. RESULTS At a median follow-up of 9.2 years, 5-year survival and EFS rates for the entire cohort were 89% +/- 3% and 77% +/- 4%, respectively. In univariate models, positive surgical margins (P =.004), tumor size > or = 5 cm (P <.001), invasivene (P =.002), high grade (P =.028), and intra-abdominal primary tumor site (P =.055) adversely affected EFS. All of these factors except invasiveness remained prognostic of EFS and survival in multivariate models. Positive surgical margins (P =.003), intra-abdominal primary tumor site (P =.028), and the omission of radiation therapy (P =.043) predicted local recurrence, whereas tumor size > or = 5 cm (P <.001), invasiveness (P <.001), and high grade (P =.004) predicted distant recurrence. CONCLUSION In this largest single-institution analysis of pediatric patients with surgically resected NRSTS, we identified clinicopathologic features predictive of poor outcome. These variables should be prospectively evaluated as risk-adapted therapies are developed.

Chemotherapy Dose-Intensification for Pediatric Patients With Ewing's Family of Tumors and Desmoplastic Small Round-Cell Tumors: A Feasibility Study at St. Jude Children's Research Hospital

PURPOSE To evaluate the feasibility of dose-intensification for patients with Ewings family of tumors (EFT) and desmoplastic small round-cell tumors. PATIENTS AND METHODS From February 1992 to June 1996, we treated 53 consecutive patients on our Ewings protocol. Induction comprised three cycles of ifosfamide/etoposide on days 1 to 3 and cyclophosphamide (CTX)/doxorubicin on day 5, followed by granulocyte colony-stimulating factor. Local control using surgery and/or radiotherapy started at week 9 along with vincristine/dactinomycin. Maintenance included four alternating cycles of ifosfamide/etoposide and doxorubicin/CTX, with randomization to one of two CTX dose levels to determine the feasibility of dose-intensification during maintenance. RESULTS Patients had a median age of 13.4 years (range, 4.5 to 24.9 years); 34 patients were male and 43 patients were white. Nineteen patients presented with metastatic disease, 29 had tumors greater than 8 cm in diameter, and 26 had primary bone tumors. These patients received 155 induction cycles, 91% of which resulted in grade 4 neutropenia, 68% in febrile neutropenia, and 68% in grade 3 to 4 thrombocytopenia. During maintenance, grade 4 neutropenia and grade 3 to 4 thrombocytopenia occurred in 81% and 85% of cycles, respectively. Thirty-five patients (66%) completed all therapy, only 13 without significant delays; three developed secondary myeloid malignancies. The toxicity and time to therapy completion were similar in both CTX arms. Estimated 3-year survival and event-free survival were 72%+/-8% and 60%+/-9%, respectively. CONCLUSION Although intensifying therapy seems feasible for 25% of patients on this study, toxicity was considerable. Therefore, the noninvestigational use of dose-intensification in patients with EFT should await assessment of its impact on disease-free survival.

Increased mortality after successful treatment for Hodgkin's disease.

PURPOSE To determine the impact of treatment toxicity on long-term survival in pediatric Hodgkins disease. PATIENTS AND METHODS We studied late events in 387 patients treated for pediatric Hodgkins disease on four consecutive clinical trials at St Jude Childrens Research Hospital from 1968 to 1990. Relative risks, actuarial risks, and absolute excess risks for cause-specific deaths were calculated. RESULTS As of April 1997, 316 (82%) of patients were alive, with a median follow-up of 15.1 (range, 2.9 to 28.6) years. In this cohort, which represented 5,623 person-years of follow-up, 71 fatal events resulted from Hodgkins disease (n=36), second malignancies (n=14), infections (n=7), accidents (n=7), cardiac disease (n=6), and asphyxiation (n=1). The 5-year estimated event-free survival (EFS) for the entire cohort was 79.6%+/-2.1 %, which declined to 63.1%+/-4.4% by 20 years. Cumulative incidences of cause-specific deaths at 25 years were 9.8%+/-1.6% for Hodgkins disease, 8.1%+/-2.6% for second malignancy, 4.0%+/-1.8% for cardiac disease, 3.9%+/-1.5% for infection, and 2.1%+/-0.8% for accidents. Standardized incidence ratios showed excess risk for all second malignancies (12; 95% confidence interval [CI], 8 to 17), acute myeloid leukemia (81; 95% CI, 16 to 237), solid tumors (11; 95% CI, 7 to 16), and breast cancer (33; 95% CI, 12 to 72). Standardized mortality ratios also showed excess mortality from cardiac disease (22; 95% CI, 8 to 48) and infection (18; 95% CI, 7 to 38). CONCLUSION Compared with age- and sex-matched control populations, survivors of pediatric Hodgkins disease who were treated before 1990 face an increased risk of early mortality related to second cancers, cardiac disease, and infection.

Carboplatin/Ifosfamide Window Therapy for Osteosarcoma: Results of the St Jude Children’s Research Hospital OS-91 Trial

PURPOSE To determine the activity of carboplatin/ifosfamide in patients with previously untreated osteosarcoma and to estimate patient outcomes after a multiagent chemotherapy protocol that eliminated cisplatin. PATIENTS AND METHODS Sixty-nine patients with newly diagnosed, previously untreated osteosarcoma received three cycles of carboplatin (560 mg/m(2) x 1) and ifosfamide (2.65 g/m(2)/d x 3). Assessment of response was evaluated after two (week 6) and three (week 9) chemotherapy cycles. At week 9, histologic response was assessed. Adjuvant therapy comprised two additional carboplatin/ifosfamide cycles, doxorubicin, and high-dose methotrexate. Patients were stratified at enrollment: stratum A, resectable primary tumor without metastases; stratum B, unresectable primary tumor; and stratum C, metastatic disease at diagnosis. Week 6 response was compared with that of a historic group that received only ifosfamide during the initial window evaluation. RESULTS The clinical and radiographic response rate to three cycles of carboplatin/ifosfamide was 67.7% (95% confidence interval, 55.0% to 78.8%). Compared with the historic population who received only ifosfamide, the combination of carboplatin and ifosfamide reduced the progressive disease rate at week 6 (31.9% v 9%, P: = .003). For patients in stratum A, the 3-year event-free survival and survival were 72.3% +/- 6.7% and 76.4% +/- 6.4%, respectively. Patients who received carboplatin-based therapy had less long-term renal toxicity and ototoxicity. CONCLUSION This pilot trial suggests that carboplatin/ifosfamide combination chemotherapy has substantial antitumor activity. In the context of a multiagent chemotherapy protocol comprising high-dose methotrexate and doxorubicin, we found that the addition of carboplatin/ifosfamide resulted in patient outcomes comparable to trials using cisplatin-based therapy with less long-term toxicity.

Use of Reverse Transcriptase Polymerase Chain Reaction for Diagnosis and Staging of Alveolar Rhabdomyosarcoma, Ewing Sarcoma Family of Tumors, and Desmoplastic Small Round Cell Tumor

Purpose To compare the use of reverse transcriptase polymerase chain reaction (RT-PCR) with that of morphology-based methods for diagnosis, staging, and detection of metastatic disease in pediatric alveolar rhabdomyosarcoma (ARMS), Ewing sarcoma family of tumors (ESFT), and desmoplastic small round cell tumors (DSRCT). Materials and Methods RT-PCR assays for the EWS-FLI1, EWS-ERG, PAX3-FKHR, PAX7-FKHR, and EWS-WT1 fusion transcripts were performed on RNA extracted from the primary tumor tissue, bone marrow, and body fluids obtained at initial presentation and relapse. Molecular findings were compared with original histologic diagnoses and results of staging procedures. Results Eighty-eight samples from 47 patients with ARMS (n = 13), ESFT (n = 31), or DSRCT (n = 3) were analyzed. The detection rate of metastatic disease was significantly higher with RT-PCR (95%) as compared with the morphologic methods (70%) for the three pediatric sarcomas studied. In primary tumors with characteristic fusion transcript, RT-PCR was positive in all cases with morphologic evidence of metastatic disease. Moreover, in six patients (3 with ARMS, 2 with DSRCT, and 1 with ESFT) with metastatic disease, micrometastases in bone marrow (4) and other sites (2) were detected by RT-PCR alone. Importantly, none of the patients with localized disease diagnosed had micrometastases detected by RT-PCR in bone marrow. Conclusions The high sensitivity and specificity of RT-PCR for the characteristic fusion transcripts of pediatric sarcomas make it an ideal method to aid in the routine staging of these patients. In addition, the 100% sensitivity of RT-PCR in detection of micrometastasis makes it useful for follow-up and detection of minimal residual disease. However, the clinical significance of molecularly-detectable disease remains unknown. Further studies should aim to elucidate the therapeutic and prognostic implications of micrometastases detected by RT-PCR alone.

Brain metastases in pediatric Ewing sarcoma and rhabdomyosarcoma : The St. Jude Children's Research Hospital Experience

PURPOSE Although brain metastases rarely occur in children with solid tumors, pediatric Ewing sarcoma (ES) and rhabdomyosarcoma (RMS) are among those most likely to metastasize to the brain. The authors review their institutions experience of brain metastases of ES and RMS. PATIENTS AND METHODS The clinical characteristics, therapy, and outcome of all patients treated at St. Jude Childrens Research Hospital over a 36-year period who had ES or RMS with brain metastases were reviewed. RESULTS Of 419 patients with RMS, 10 (2.4%) had brain metastases. Of 335 patients with ES, 11 (3.3%) had brain metastases. The median age of the 21 patients was 10.4 years (range, 0.4-18.0 years) at the time of primary diagnosis. All had clinical signs of central nervous system (CNS) involvement. Outcome was dismal: The median duration of survival after diagnosis of brain metastasis was 2.7 months. The estimated survival 1 year after detection of brain involvement was 23.8%+/-8.5% (mean +/- standard error). One patient, who underwent chemotherapy, surgical resection, and radiotherapy, at the time of this writing is a long-term survivor. CONCLUSIONS Brain metastases are rare in children with ES and RMS, but carry a grave prognosis. Because most brain metastases are accompanied by signs of neurologic involvement, routine imaging studies of asymptomatic children are not necessary. Combined-modality treatment offers the best chance of long-term survival.

Fractures in pediatric Ewing sarcoma

Purpose To determine the incidence, timing, and clinical significance of long-bone fractures in children with Ewing sarcoma family of tumors (ESFT). Patients and Methods We retrospectively reviewed 93 consecutive cases of ESFT of the long bones seen at a single institution over the course of a 37-year period. Results Fracture occurred in 14 (15%) of 93 patients with long-bone ESFT, most commonly in the femur. Approximately 30% of patients with tumors of the femur had fractures at some point in the course of their disease. The incidence of fracture was highest among patients with tumors of the proximal third of the femur (50%); these fractures were usually present at the time of initial diagnosis. Nine (64%) of the 14 fractures occurred after the start of radiotherapy, and three of these were associated with either local recurrence or second malignancy. Conclusions Patients with femoral ESFT are at high-risk for fracture. If fractures occur after the completion of therapy, recurrence or second malignancy should be suspected.

Hematologic abnormalities and acute myeloid leukemia in children and adolescents administered intensified chemotherapy for the ewing sarcoma family of tumors

PURPOSE Current treatment of the Ewing sarcoma family of tumors (ESFT) includes intensive multiagent chemotherapy with topoisomerase II inhibitors, alkylating agents, and granulocyte colony-stimulating factor (G-CSF). This treatment approach has been associated with myelodysplasia and acute myeloid leukemia. Because macrocytosis and thrombocytopenia are distinctive features of myelodysplasia, the authors evaluated a cohort of patients treated for ESFT to determine the degree and duration of macrocytosis and thrombocytopenia and their relation with the development of therapy-related hematologic malignancies. PATIENTS AND METHODS The study group consisted of 73 patients with ESFT treated on two consecutive protocols (EW92 and EW87). Both chemotherapy regimens incorporated the same agents but differed in cumulative drug dose, dose per course, and the use of G-CSF. Platelet counts and the mean corpuscular volume (MCV) of erythrocytes were determined at diagnosis and during follow-up visits after completion of treatment. RESULTS Patients in the EW92 group had significantly greater MCVs after treatment than did the less intensively treated EW87 group. These changes persisted throughout the 40-month observation period. Patients in the EW92 group also had lesser mean platelet counts after treatment than those in the EW87 group. MCV differences (from baseline) were inversely related to platelet counts. The cumulative incidence of treatment-related acute myeloid leukemia was 7.8%+/-4.7% at 4 years in the EW92 group and zero in the EW87 group. CONCLUSION Patients treated for ESFT with intensive chemotherapy that includes large doses of alkylators, topoisomerase II inhibitors, and G-CSF characteristically have persistently elevated MCVs and decreased platelet counts after completion of therapy. These hematologic abnormalities may represent stem cell damage, predisposing patients to myelodysplasia and acute myeloid leukemia, but further study is needed to establish this relation.

Comparative renal tubular toxicity of Chemotherapy regimens including ifosfamide in patients with newly diagnosed sarcomas

PURPOSE The aim of this study was to assess renal tubular toxicity (RTT) of ifosfamide-containing regimens (ICR) in patients with newly diagnosed sarcomas at St. Jude Childrens Research Hospital. METHODS The authors reviewed the records of 199 patients receiving ICR at St. Jude between June 1986 and December 31, 1994 for evidence of RTT. Their median age was 13.3 years (range 1.2-24.8); 150 patients were white and 112 were male patients. Diagnoses included osteosarcoma (n = 82), Ewing sarcoma (n = 82), rhabdomyosarcoma (n = 28), and a group of other tumors (n = 7). RESULTS The authors estimated the proportion of patients with severe RTT during the first five cycles of ICR and within 1 year after therapy for three groups of patients receiving ifosfamide (IFOS, n = 110), ifosfamide/cisplatin (IFOS/CDDP, n = 51), and ifosfamide/carboplatin (IFOS/CARBO, n = 38). The IFOS/CDDP patients received three cycles of IFOS before receiving CDDP and received only 200 mg/m2 by cycle 5, whereas the IFOS/CARBO patients received both agents simultaneously. The authors compared the probability of severe RTT among treatment groups using a generalized linear model for the first five cycles of ICR, as well as the probability of severe RTT within 1 year after therapy among treatment groups for patients receiving all prescribed IFOS using an exact chi-square test with pairwise comparisons when the three-way P value was less than 0.10. The proportion of patients with severe RTT during the first three cycles of ICR was significantly greater in the IFOS/CARBO group than in the other two. Although the proportion of patients with severe RTT in the IFOS/CDDP group increased during cycles 4/5, the proportion of patients with severe RTT remained significantly greater in the IFOS/ CARBO group. Within 1 year after therapy, the proportion of patients with severe RTT differed among the three groups, and pairwise comparisons revealed a significant difference between the IFOS and the IFOS/CDDP group. Severe RTT developed in four IFOS/CDDP patients more than 1 year after therapy, suggesting a long-term effect of CDDP on tubular function. CONCLUSIONS Chemotherapy regimens including IFOS/ CARBO produce severe acute RTT more frequently than regimens including IFOS or IFOS/CDDP. Patients receiving IFOS/ CDDP appear at risk for delayed RTT. Long-term follow-up of these patients is essential to assess whether the number of patients receiving IFOS/CDDP with severe RTT continues to increase over time and to evaluate the long-term significance of these abnormalities.