Up-front window trial of topotecan in previously untreated children and adolescents with metastatic rhabdomyosarcoma: an intergroup rhabdomyosarcoma study

PURPOSE

To investigate the antitumor activity and toxicity of topotecan, used alone and in combination with conventional therapy, in patients with metastatic rhabdomyosarcoma (RMS).

PATIENTS AND METHODS

Forty-eight patients younger than 21 years of age with newly diagnosed metastatic RMS received 2.0 to 2.4 mg/m(2) of topotecan intravenously daily for 5 days every 21 days before standard therapy. Two courses were given in the absence of progressive disease or excessive toxicity and response was assessed. Patients with at least a partial response (PR) to topotecan proceeded to therapy with alternating courses of vincristine 1.5 mg/m(2), dactinomycin 1.5 mg/m(2), and cyclophosphamide 2.2 g/m(2) (VAC) and vincristine 1.5 mg/m(2), topotecan 0.75 mg/m(2) daily x 5, and cyclophosphamide 250 mg/m(2) daily x 5. Patients who did not respond to topotecan received continuation therapy with VAC alone.

RESULTS

The overall response rate to topotecan was 46% (complete response, 4%; partial response 42%). Unexpectedly, patients with alveolar RMS had a higher rate of response (65%) than those with embryonal RMS (28%; P: = .08). The most common grade 3 or 4 toxicities were neutropenia (67%), anemia (33%), thrombocytopenia (25%), and infection (21%). Two-year failure-free survival and survival estimates were 24% and 46%, respectively. Response to window therapy did not correlate with survival.

CONCLUSION

The high response rate and acceptable toxicity profile of topotecan in children with advanced RMS support further evaluation of this agent in phase III trials. The superior responses in alveolar RMS are of interest.

Childhood carcinoid tumors: the St Jude Children's Research Hospital experience

BACKGROUND/PURPOSE

To better characterize childhood carcinoid tumors, the authors reviewed the clinical presentation, treatment, and outcomes of pediatric patients with these rare tumors.

METHODS

A retrospective review was conducted of medical records and pathologic materials of all children with carcinoid tumors treated at St Jude Children's Research Hospital between December 1977 and March 1999.

RESULTS

Eight patients (median age, 12.7 years) were identified; 2 were boys, and 7 were white. Primary tumor sites were the appendix (n = 5), small intestine (n = 1), bronchus (n = 1), and 1 unknown site. In 7 cases, carcinoid tumor was not suspected at the time the tumor was identified. Seven patients had localized disease; 5 remain disease-free after complete resection, and 2, whose carcinoid tumors were identified incidentally, died of metastatic mucinous adenocarcinoma of the colon. One patient who presented with symptoms of carcinoid syndrome had metastatic disease that responded poorly to cytotoxic chemotherapy and remains alive with active disease.

CONCLUSIONS

Although most pediatric carcinoid tumors arise in the appendix, these tumors also occur in other primary sites. Clinical awareness and early diagnosis are important factors in preventing morbidity and mortality. Outcomes are excellent for patients with localized disease that is completely resected, but those with metastatic disease fare poorly. New therapeutic strategies are needed for these patients.

Long-term results with radiation therapy for pediatric desmoid tumors

PURPOSE

To retrospectively review the treatment and outcome of pediatric patients with desmoid tumor who received radiation therapy at a single institution.

MATERIALS AND METHODS

Thirteen pediatric patients received radiation therapy for desmoid tumor at St. Jude Children's Research Hospital between 1962 and 1998. Only 2 of the patients reviewed received treatment prior to 1976. The median dose of external beam irradiation was 50 Gy.

RESULTS

At the time of this report, 10 of 13 patients have had tumors that recurred after radiation therapy and 3 have died from their disease. One additional patient was harboring a recurrence, and 1 had not been followed long enough to suggest that the patient had achieved disease control. One patient remained locally controlled after radiation therapy with long-term follow-up (196 months). The median time to recurrence following radiation therapy was 19 months (range, 3-135 months). Eight of the 13 patients suffered substantial tumor and treatment-related morbidity.

CONCLUSIONS

Desmoid tumors in pediatric patients are locally aggressive tumors that are likely to recur after radiation therapy. Alternatives to radiation therapy should be sought for the treatment of these tumors, and efforts should focus on low-morbidity therapies aimed at inhibiting the growth of these unique tumors.

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.

Nonrhabdomyosarcoma soft tissue sarcomas in children: is age at diagnosis an important variable?

PURPOSE

The associations between age at diagnosis, tumor characteristics, and outcome in children diagnosed with nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) were studied.

METHODS

Retrospective review was conducted of 192 children from 1962 through 1996. Patients were divided into groups: birth to 1 year (n = 13), 1 to 5 years (n = 26), 5 to 10 years (n = 49), 10 to 15 years (n = 55), and older than 15 years (n = 49) of age at diagnosis. Characteristics including IRS group, histological grade and pattern, tumor size, and invasiveness were investigated. Survival rate was estimated by age group. The median follow-up was 8.8 years (range, 2 to 28 years).

RESULTS

There were 81 group I patients, 40 group II, 41 group III, and 30 group IV. A significant difference of IRS groups among the age groups was seen (P = .034). There were no IRS group IV patients less than 1 year of age; 50% of IRS group IV patients were older than 15 years. A significant difference in the distribution of histological grade among the age groups (P = .032) was seen. Ten of 13 (77%) children less than 1 year of age had low-grade tumors, whereas 42%, 45%, 60%, and 37% of patients aged 1 to 5, 5 to 10, 10 to 15, and older than 15 years, respectively, had low-grade tumors. Patients older than 15 years had the highest incidence of invasive tumors (59%). Histological pattern also varied with age. The most prevalent histology in the less-than-1-year age group was infantile fibrosarcoma. No predominant histology was seen in the 1- to 5-year age group. Malignant fibrous histiocytoma was the most frequent histological subtype in children between 5 and 10 years of age. In the 10- to 15-year age group and children older than 15 years the malignant peripheral nerve sheath tumor and synovial sarcoma were the most prevalent subtypes. Without adjusting for any other factors, age group was prognostic of survival (P = .007). Patients less than 1 year at diagnosis had the best outcome, with a 5-year survival rate of 92% +/- 9%. Five-year estimates were lowest for patients older than 15 years (49% +/- 7%).

CONCLUSIONS

Significant differences in IRS group, histological grade, and histological subtype were observed in different age groups. Infants with NRSTS were more likely to have low grade, less invasive, and lower stage tumors. These characteristics may account for their improved prognosis.

Sentinel lymph node biopsy for melanoma in young children

Lymphoscintigraphy and sentinel lymph node biopsy techniques can be applied successfully to young children with melanoma to detect nodal disease. The authors describe their methods of lymphoscintigraphy and sentinel node biopsy and its application in 2 young children with malignant melanoma of the head and neck.

Aggressive surgery is unwarranted for biliary tract rhabdomyosarcoma

BACKGROUND/PURPOSE

Rhabdomyosarcoma (RMS) of the biliary tract is rare, and, in addition to multiagent chemotherapy with or without radiotherapy (RT), some investigators recommend aggressive surgery. To assess the role of surgery, records of all 25 eligible patients with biliary RMS enrolled in IRSG studies I through IV from 1972 to 1998 were reviewed.

METHODS

Treatment included surgery with or without vincristine, dactinomycin, cyclophosphamide, doxorubicin, cisplatin, etoposide, ifosfamide, and with or without RT. Data evaluated included clinical presentation, treatment, complications, and outcome.

RESULTS

Diagnostic imaging identified the primary tumor but failed to identify regional metastases. Despite aggressive surgery, gross total resection at diagnosis was possible in only 6 cases, 2 of which had negative surgical margins. Although only 6 (29%) patients without distant metastases underwent gross total resection, estimated 5-year survival rate was 78% (95% CI 58%, 97%). Infectious complications were common and frequently associated with external biliary drains. Five (20%) died within the first 2 months, 3 of sepsis.

CONCLUSIONS

Surgery is critical for establishing an accurate diagnosis and determining the extent of regional disease. Gross total resection is rarely possible despite aggressive surgery, and outcome is good despite residual disease after surgery. External biliary drains increase the risk of postoperative infectious complications.

Hemangiopericytoma in children and infants

BACKGROUND

Hemangiopericytoma (HPC) is a soft-tissue neoplasm most commonly seen in adults; only 5-10% of cases occur in children. Childhood HPC comprises two distinct clinical entities. In children older than 1 year, it behaves in a manner similar to adult HPC. Infantile HPC, however, although histologically identical to adult HPC, has a more benign clinical course. The reasons for these differences in the natural history of HPC are not well understood.

METHODS

The authors reviewed the clinicopathologic features of HPC as well as the treatment and outcomes of the 12 children (9 males and 3 females) treated for this disease at St. Jude Children's Research Hospital over a 35-year period.

RESULTS

At diagnosis, 9 patients were older than 1 year and 3 were younger than 1 year. Among the 9 older patients, tumors were most commonly found in the lower extremities (n = 5). One patient had been treated for acute lymphoblastic leukemia 15 years earlier. One patient had metastatic disease at diagnosis, and three had unresectable tumors. Two patients experienced objective responses to chemotherapy. Three patients died of disease progression. Among the three infants, two had unresectable disease at diagnosis, and both experienced excellent responses to neoadjuvant chemotherapy. In one case, the response of the tumor to chemotherapy correlated with maturation to hemangioma. All three infants are alive without evidence of disease.

CONCLUSIONS

HPC in children older than 1 year does not differ from adult HPC, and aggressive multimodality therapy is required. Infantile HPC, on the other hand, is characterized by better clinical behavior, with documented chemoresponsiveness and spontaneous regression, and requires a more conservative surgical approach. In some cases of infantile HPC, this benign behavior correlates with maturation to hemangioma.

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.

Survival after relapse in children and adolescents with rhabdomyosarcoma: A report from the Intergroup Rhabdomyosarcoma Study Group

BACKGROUND

Despite advances in therapy, nearly 30% of children with rhabdomyosarcoma experience progressive or relapsed disease, which is often fatal.

PATIENTS AND METHODS

To facilitate the development of a retrieval therapy protocol, we studied potential risk factors that were predictive of survival after first relapse in 605 children who were enrolled onto three consecutive Intergroup Rhabdomyosarcoma Study Group protocols.

RESULTS

The median survival time from first recurrence was 0.8 years; the estimated percentage of patients who survived 5 years from first recurrence was 17% +/- 2% (mean +/- SD). Univariate analysis showed that tumor histology was an important predictor of 5-year survival (P <.001): the 5-year survival rate was 64% for patients with botryoid tumors (n = 19), 26% for patients with embryonal tumors (n = 313), and 5% for patients with alveolar or undifferentiated sarcoma (n = 273). Further analysis identified prognostic factors within histologic subtypes (P <.001). For patients with embryonal tumors, the estimated 5-year survival rate was 52% for patients who initially presented with stage 1 or group I disease, 20% for those with stage 2/3 or group II/III disease, and 12% for those with group IV disease. For patients with stage 1/group I disease, estimated 5-year survival rates were higher for patients with local (72%) or regional (50%) recurrence than for those with distant (30%) recurrence. Among patients with alveolar or undifferentiated sarcoma, only the disease group predicted outcome: the 5-year survival estimate was 40% for group I versus 3% for groups II through IV. We identified a "favorable risk" group (approximately 20% of patients) whose 5-year estimated survival rate was near 50%; for all other patients, the estimated survival was near 10%.

CONCLUSION

This analysis demonstrates that the probability of 5-year survival after relapse for rhabdomyosarcoma is dependent on several factors at the time of initial diagnosis, including histologic subtype, disease group, and stage. These findings will form the basis of a multi-institutional risk-adapted relapse protocol for childhood rhabdomyosarcoma.

Clear cell sarcoma of soft tissues in children and young adults: the St. Jude Children's Research Hospital experience

Clear cell sarcoma is a rare soft tissue neoplasm whose clinical behavior and outcome has not been previously characterized. This study reviewed the clinical characteristics and outcome of all children with clear cell sarcoma of the soft tissues who were treated at St. Jude Children's Research Hospital from March 1962 through August 1998. Of 225 children with nonrhabdomyosarcomatous soft tissue sarcomas, 5 (2.2%) were diagnosed with clear cell sarcoma. Median age at diagnosis was 15 years 3 months. Primary sites included the extremities (n = 3), chest wall (n = 1), and abdomen (n = 1). At diagnosis 3 patients had localized disease. Following surgical resection (n = 3), radiotherapy (n = 2), and chemotherapy (n = 1) all three survive disease-free 10, 11, and 90 months after diagnosis, respectively. The remaining two patients with metastatic disease at diagnosis died 21 days and 9 months after diagnosis. Clear cell sarcoma of the soft tissues is rare in pediatrics. Complete surgical resection with negative margins is the most effective treatment for this disease. Patients with metastatic disease are candidates for multiinstitutional chemotherapy trials.

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 institution's experience of brain metastases of ES and RMS.

PATIENTS AND METHODS

The clinical characteristics, therapy, and outcome of all patients treated at St. Jude Children's 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.

Metastatic nonrhabdomyosarcomatous soft-tissue sarcomas in children and adolescents: the St. Jude Children's Research Hospital experience

BACKGROUND

Because the natural history of pediatric patients with metastatic nonrhabdomyosarcomatous soft-tissue sarcomas (NRSTS) had not been well described, we retrospectively reviewed our single-institution experience with these tumors.

PROCEDURE

We identified 26 patients with metastatic NRSTS who were treated at St. Jude Children's Research Hospital from December 1971 through July 1995. We evaluated the characteristics of each patient, including age, sex, primary site, stage, type of therapy received, and outcome. Sites of metastatic disease at diagnosis and relapse were noted.

RESULTS

The median age of the 26 study patients at diagnosis was 14. 8 years; 54% of patients were male and 69% were white. The most common histologies were synovial sarcoma, alveolar soft-part sarcoma, and malignant fibrous histiocytoma. Most primary tumors (73% of cases) occurred in the trunk or extremities. Most patients presented with large (>5 cm), high-grade lesions. All 26 patients received chemotherapy, and 8 responded to an ifosfamide- or cyclophosphamide-doxorubicin-based regimen. Radiotherapy was administered to 15 patients, and 13 had a partial or complete resection of the primary tumor. Six patients underwent thoracotomy. The estimated 2-year survival for the cohort was 34.6% +/- 8.9%; the 2-year progression-free survival was 15.4% +/- 6.3%. The lung was the most common site of failure.

CONCLUSIONS

Children with metastatic NRSTS have a poor outcome, which is similar to that in adults. More effective systemic chemotherapy is needed to facilitate complete surgical resection of primary and metastatic sites. Aggressive pulmonary metastatectomy can increase disease control.

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.

Interpatient variability in bioavailability of the intravenous formulation of topotecan given orally to children with recurrent solid tumors

PURPOSE

Evaluation of inter- and intrapatient variability of topotecan oral bioavailability and disposition was performed in children with malignant solid tumors.

PATIENTS AND METHODS

Topotecan i.v. formulation was given orally on schedules of daily for 21 consecutive days (d x 21) or daily for 5 days per week for 3 weeks [(d x 5)3], in both cases repeated every 28 days. Topotecan doses of 0.8 and 1.1 mg/m2 per day were evaluated on both schedules. Serial plasma samples were obtained after oral and i.v. administration of topotecan at the beginning and end of the first course of therapy. Topotecan lactone and total concentrations were measured by a high-performance liquid chromatography (HPLC) assay, and a one-or two-compartment model was fit to the plasma concentration-time data after oral or i.v. administration, respectively. Topotecan oral bioavailability (F) was calculated as the ratio of the AUC determined after oral treatment (AUCpo) divided by the AUC calculated after i.v. administration.

RESULTS

Pharmacokinetics studies were performed on 15 and 11 patients receiving 0.8 and 1.1 mg/m2 per day, respectively. After oral administration the topotecan lactone AUCpo and F determined for 0.8 and 1.1 mg/m2 per day were 13.6 +/- 5.8 and 25.1 +/- 12.9 ng ml(-1) h and 0.34 +/- 0.14 and 0.34 +/- 0.16, respectively. The within-patient variance for AUCpo and F was much smaller than the between-patient variance. The ratio of topotecan lactone to total concentration was consistently higher after oral as compared with i.v. administration.

CONCLUSIONS

Large interpatient variability was noted in topotecan pharmacokinetics, whereas intrapatient variability was relatively small. Further studies of oral topotecan are warranted to evaluate the tolerance of shorter courses and to define further the interpatient variability.

The impact of margin of resection on outcome in pediatric nonrhabdomyosarcoma soft tissue sarcoma

BACKGROUND/PURPOSE

Because the management of pediatric nonrhabdomyosarcoma soft tissue sarcomas (NRSTS) is determined by extrapolation from adult studies, the effect of margin of tumor resection and postoperative radiation therapy (RT) on local tumor recurrence in children has not been assessed.

METHODS

Records of NRSTS patients from a single institution were reviewed with regard to demographic data, TNM staging, grade, histological type and site of primary tumor, RT, and local tumor recurrence. The margin of resection was determined by pathological review and did not necessarily reflect operative margins.

RESULTS

Eighty-eight clinical group I patients were treated over a 30-year period. The most common histological tumor subtypes were synovial cell sarcoma (n = 26), malignant fibrous histiocytoma (n = 17), and fibrosarcoma (n = 7). The mean age was 9.4 years (range, 0 to 29 years). Thirty-four patients had high-grade tumors. Two of ten patients with low-grade tumors and margins less than 1 cm, including one of five who had received RT, had a local recurrence. Patients with low-grade tumors and margins greater than 1 cm (n = 44) had a lower recurrence rate (2 of 44, 4.5%). None of these patients had received RT. Fourteen patients with high-grade tumors had margins less than 1 cm. Seven of these had RT and had no recurrence. Three of the seven patients who received no RT had a recurrence (42.9%). None of the 20 patients with high-grade tumors and margins greater than 1 cm received RT; four of these patients had recurrences (20%). Seven of the 12 irradiated patients (58.3%) had serious radiation-associated complications (wound dehiscence, fracture, growth retardation, and joint dysfunction).

CONCLUSIONS

Grade alone does not determine the rate of local recurrence. In both low- and high-grade tumors, a pathological margin of resection greater than 1 cm reduced local recurrence. Radiotherapy provided no advantage in low grade tumors but did decrease local recurrence rates in high-grade tumors with less than 1 cm pathological margins.

Role of adjuvant chemotherapy in the treatment of surgically resected pediatric nonrhabdomyosarcomatous soft tissue sarcomas: A Pediatric Oncology Group Study

PURPOSE

To prospectively study the value of adjuvant chemotherapy in pediatric patients with surgically resected nonrhabdomyosarcomatous soft tissue sarcomas (NRSTS).

PATIENTS AND METHODS

From June 1986 to May 1992, after complete surgical resection (+/-radiotherapy) of their NRSTS, 81 eligible patients either received adjuvant chemotherapy comprising vincristine, dactinomycin, cyclophosphamide, and doxorubicin or were observed. Only 30 patients accepted randomization, and 15 were assigned to each regimen. Of the remaining 51 patients, 19 elected adjuvant chemotherapy and 32 elected observation.

RESULTS

Patients were predominantly male, and 69% of all patients were white. The median age at diagnosis was 12.3 years (range, 9.2 to 20.7 years). For the 81 eligible patients, the 5-year overall survival estimate was 84.5% +/- 4.4% and event-free survival was 72.2% +/- 5.4%. Among randomized patients, the 5-year estimated overall survival rate was 93.3% +/- 7%, and the event-free survival rate was 86.7% +/- 9.5% for the observation group, compared with 69.2% +/- 13% and 40.7% +/- 14%, respectively, for those who received chemotherapy. The significantly worse outcome of patients who received adjuvant chemotherapy disappeared when survival was stratified by tumor grade. Among all patients, a grade 3 lesion conferred a significant disadvantage with respect to event-free survival (P =.0001).

CONCLUSION

The administration of adjuvant chemotherapy according to the schedule and dosages used in our trial did not improve the outcome of children with resected NRSTS. In this study, tumor grade was the most important predictor of clinical outcome in patients with resected NRSTS, and this factor should be incorporated into the stratification of patients in future trials.

Soft tissue sarcomas in children

In childhood, soft tissue sarcomas comprise a complex group of malignancies of varied histologic subtypes, the prognoses of which depend on the histology, age, site, extent of involvement and a variety of other factors. This paper discusses the varieties of tumors classified as soft tissue sarcomas in childhood and the multimodal approach taken to cure these tumors, with particular attention to the details of difficult surgical problems.

Phase I targeted systemic exposure study of paclitaxel in children with refractory acute leukemias

Clearance of anticancer drugs in children is highly variable, leading to wide variability in the systemic exposure associated with each dosage escalation in Phase I studies. The purpose of this Phase I study was to escalate targeted systemic exposure to paclitaxel, rather than dose, to attenuate the impact of pharmacokinetic variability at each escalation level. Children with recurrent acute leukemias received paclitaxel as 24-h infusions at escalating levels of paclitaxel systemic exposure [i.e., area under the concentration-versus-time curve (AUC)]. Plasma paclitaxel concentrations were measured by high-performance liquid chromatography-UV detection. A Bayesian algorithm using a two-compartment model with saturable distribution and saturable elimination was used to estimate clearance during the first 8 h of infusion; the infusion rate was adjusted 12 h after the start of infusion to achieve the target AUC. Toxicity and evidence of activity were assessed after each course. Six boys and one girl received eight courses of paclitaxel. The target AUC ranged from 31.5 to 45 microM x h. Five of the seven evaluable courses had AUCs between 75% and 125% of the target after adjustment (median, 100.2%; range, 51-151%), whereas none of the seven courses was projected to be in the target range had no change in dose been made (P = 0.021). The ratio of the achieved AUC to the target AUC was inversely related to clearance (r = -0.857; P = 0.014). Mucositis was the exposure-limiting toxicity, at AUCs lower than were expected based on Phase I studies in children with solid tumors. Pharmacokinetically-guided dosing strategies reduced variability in systemic exposure. Alternatives to traditional Phase I studies may be important in the setting of childhood leukemias because these patients show poor tolerance to Phase I therapy.

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 Ewing's 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 Ewing's 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.

Pediatric primary diffuse large cell lymphoma of bone with t(3;22)(q27;q11)

PURPOSE

A child with a primary lymphoma of bone (PLB) with a t(3;22)(q27;q11) is described.

METHODS

An 11-year-old boy had a 5-week history of back pain and a destructive lesion of S1 that contained an epidural component. Histologic evaluation of a biopsy confirmed the diagnosis of diffuse large B-cell non-Hodgkin lymphoma. Karyotypic analysis disclosed a t(3;22)(q27;q11), but the amount of tumor tissue was insufficient for molecular studies of the BCL-6 gene.

RESULTS

The patient remains free of disease 4 years after completion of intensive systemic chemotherapy and intrathecal chemotherapy.

CONCLUSIONS

The lymphoma in the patient described in this report is highly unusual because of the coexistence of pediatric PLB and a t(3;22)(q27q11).

A pilot study of vincristine, ifosfamide, and doxorubicin in the treatment of pediatric non-rhabdomyosarcoma soft tissue sarcomas

BACKGROUND

Standard therapy for pediatric nonrhabdomyosarcoma soft tissue sarcomas (PNRSTS) consists of surgical resection with or without radiotherapy. The role of chemotherapy in the treatment of these tumors has not yet been defined. We investigated the efficacy and toxicity of an ifosfamide-based regimen in controlling disease in children with high-risk PNRSTS.

PATIENTS AND METHODS

Between January 1992 and June 1994 at St. Jude Children's Research Hospital, we treated 11 children and young adults with PNRSTS who were at high risk for treatment failure by using a combined modality regimen that comprised aggressive surgery, radiotherapy, and chemotherapy including vincristine, ifosfamide, and doxorubicin (VID). Nine of these patients had grade 3 disease and one had grade 2 tumor; due to insufficient tissue, the disease grade of the remaining patient could not be established. Metastases were present at diagnosis in 2 children.

RESULTS

Therapy was generally well tolerated, with minimal morbidity and no mortality. The most common toxicity was grade 4 neutropenia, which occurred in 51% of evaluable courses. Among 4 patients evaluable for response to chemotherapy alone, 1 child attained a partial response and 3 had stable disease. One child had a response to chemotherapy and concurrent irradiation. At a median follow-up of 30 months, 10 of 11 patients are alive; 8 of 11 patients are alive without evidence of disease.

CONCLUSION

Aggressive multimodality therapy for PNRSTS is well tolerated, despite frequent and profound neutropenia. Although adjuvant chemotherapy for this group of cancers remains unproved, the rate of tumor control achieved in this pilot study encourages further investigation in a multi-institutional setting.