Local therapy and other factors influencing site of relapse in patients with localised Ewing's sarcoma. United Kingdom Children's Cancer Study Group (UKCCSG)

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.

Survival After Recurrence of Ewing’s Sarcoma Family of Tumors

Purpose

The overall survival (OS) of patients with relapsed Ewing’s sarcoma family of tumors (ESFT) is poor, and the relative benefit of high-dose therapy (HDT) is controversial.

Patients and Methods

We retrospectively identified 55 consecutive ESFT patients with adequate medical records for review, who were treated at Children’s Hospital and Regional Medical Center and who developed disease recurrence between January 1, 1985 and December 31, 2002.

Results

The median relapse-free interval (RFI) from diagnosis to first recurrence was 17 months (range, 5 to 90 months). Most recurrences were metastatic only (39 patients) or local and metastatic (10 patients). Twenty-seven patients (49%) achieved a partial or complete response to second-line treatment, with a median duration of response of 27 months (range, 5 to 119+ months). The 5-year OS rate for all relapsed patients was 23% (95% CI, 11% to 35%). By univariate analysis, improved OS was associated with response to second-line treatment versus no response (46% v 0%, respectively; P < .0001), RFI ≥ 24 months versus less than 24 months (48% v 12%, respectively; P = .0001), and no metastases at initial diagnosis versus presence of metastases (31% v 12%, respectively; P = .05). Because all 13 patients who received HDT also had responsive relapse, we performed a multivariate analysis. Reduced risk of death was associated with response to second-line therapy (relative risk, 0.14; 95% CI, 0.05 to 0.40), RFI ≥ 24 months (relative risk, 0.29; 95% CI, 0.13 to 0.66), and receiving HDT (relative risk, 0.26; 95% CI, 0.08 to 0.85).

Conclusion

HDT as consolidation therapy for relapsed ESFT seems to be associated with improved OS, even after adjusting for RFI and response to second-line treatment.

Vascular endothelial growth factor: a therapeutic target for tumors of the Ewing's sarcoma family

PURPOSE

We have reported previously that intratumoral microvessel density (MVD) is a significant prognostic indicator of event-free survival in the Ewing's sarcoma family of tumors (ESFT). Here, the angiogenic growth factor expression profile and its relationship with MVD has been investigated in ESFT.

EXPERIMENTAL DESIGN AND RESULTS

Using ESFT model systems, the potential of these factors as therapeutic targets has been evaluated. A significant correlation (P = 0.02) was observed between vascular endothelial growth factor (VEGF) expression and MVD, consistent with the hypothesis that VEGF regulates the development of microvessels in ESFT. There was no correlation between MVD and any of the other growth factors studied. All six ESFT cell lines studied produced and secreted VEGF; five of six cell lines also secreted placental growth factor, one cell line (A673) at high levels. Tumor conditioned medium induced proliferation of human umbilical vein endothelial cells. Expression of VEGF receptors Flt-1 and Flk-1/KDR was heterogeneous across the cell lines. Both receptor tyrosine kinase inhibitors SU6668 (targets Flk-1/KDR, platelet-derived growth factor receptor-beta, and fibroblast growth factor receptor 1) and SU5416 (targets Flk-1/KDR) as well as anti-VEGF agents rhuMAb-VEGF (bevacizumab) and VEGF Trap delayed s.c. growth of ESFT in mice compared with untreated groups: SU6668 (100 mg/kg/d), SU5416 (25 mg/kg/d), rhuMAb-VEGF (10 mg/kg twice weekly), and VEGF Trap (2.5 or 25 mg/kg twice weekly).

CONCLUSIONS

These data suggest that VEGF is the single most important regulator of angiogenesis in ESFT and may be exploited for therapeutic advantage.

Definitive irradiation in multidisciplinary management of localized Ewing sarcoma family of tumors in pediatric patients: outcome and prognostic factors

PURPOSE

To assess the effect of radiation dose on local tumor control of the Ewing sarcoma family of tumors in 79 patients with localized disease treated at a single institution.

METHODS AND MATERIALS

Thirty-seven patients received vincristine, actinomycin D, cyclophosphamide, and doxorubicin, and 42 received vincristine, actinomycin D, and cyclophosphamide, with alternating cycles of ifosfamide and etoposide; all underwent definitive radiotherapy (median dose, 37.5 Gy) with either low-dose (<40 Gy) or standard dose (> or =40 Gy) radiation delivered according to the protocol. We calculated the cumulative incidence of local treatment failure, disease recurrence, and overall survival and analyzed the effect of known prognostic factors and radiation dose.

RESULTS

The cumulative incidence of local treatment failure at 10 years was 30.4% and that of disease recurrence was 40%. The overall survival rate was 64.5%. Patient age > or =14 years and tumor size > or =8 cm were adverse prognostic factors for local treatment failure; patient age > or =14 years was also associated with worse survival. Although the radiation dose alone did not predict for local treatment failure, the cumulative incidence of local failure at 10 years was 19% when tumors <8 cm were treated with <40 Gy, and no patient treated with standard doses (> or =40 Gy) developed local recurrence (p = 0.084).

CONCLUSION

Tumor size and patient age predict for local tumor control in patients with Ewing sarcoma family of tumors treated with systemic therapy and definitive radiotherapy. Patients treated with reduced-dose radiotherapy experienced unacceptably high rates of local recurrence.

Treatment results and prognostic factors in Ewing sarcoma

Files of 133 children with Ewing sarcoma (median age 10 years) were reviewed. Frequent primary sites were extremities, trunk, pelvis, and cranium. Half of 43 patients with metastases had disease in the lungs. Ten-year overall and event-free survival rates were 31% and 19%, respectively. Five-year overall survival rates were 42% in localized and 15% in metastatic disease (p < .0001); 66% in cases with primary tumors < 8 cm and 29% in larger tumors (p = .013). VAC (vincristine, actinomycin D, and cyclophosphamide) regimens with anthracyclines resulted in better survival. Presence of distant metastases, large primary tumors, and pelvic localization were related to poor prognosis. Novel therapeutic approaches are needed to produce better results, especially in high-risk patients.

Efficacy of combined surgery and irradiation for localized Ewings sarcoma family of tumors

BACKGROUND

Local tumor control for patients with Ewings sarcoma family of tumors (ESFT) is favorable when the primary tumor is resectable or small. Local failure rates for patients who received combined surgery and RT were reviewed to determine outcome and prognostic factors.

PROCEDURES

We performed a retrospective review of all patients with localized ESFT treated with combined definitive surgery and RT between 1978 and 2001, at St. Jude Children's Research Hospital. Rates of local failure, survival, and prognostic factors for recurrence were determined in 39 patients who received combined local therapy. Systemic treatment included vincristine, actinomycin D, cyclophosphamide, and doxorubicin (6 patients), with the addition of ifosfamide and etoposide (33 patients).

RESULTS

With a median follow-up of 8.7 years the 5- and 8-year survival estimates were 89.2 +/- 5.4% and 82.8 +/- 7.3%. The 8-year incidence of local failure was 10.8 +/- 5.2%. The 8-year local failure rate for patients with positive surgical margins was 17% and for negative surgical margins 5% (P = 0.25). Overall survival was improved for patients with negative surgical margins (94 vs. 71%, P = 0.052). Tumor size, site, histologic response, and radiation dose did not significantly alter the rate of local failure.

CONCLUSIONS

Patients with ESFT managed with definitive surgery and irradiation have favorable local control rates. Even among patients with unfavorable prognostic factors local tumor control remained excellent.

[Surgery of primary malignant bone tumors]

The term primary malignant bone tumors covers a diversity of entities. Tumor resection is preferable in most. In some, surgery alone is sufficient, in others therapy will be based on a combined modality concept. Resection plays the essential role in those tumors treated by surgery alone, e.g., primary osseous fibrosarcoma. The combined modality approach in osteosarcomas or Ewing's tumors provides for additional elements of local therapy (radiotherapy) or systemic treatment (chemotherapy). The relevance of surgery for local control varies in these latter diagnoses. In highly malignant osteosarcoma, where wide margin surgery is of utmost importance, only 10-20% of patients will survive longer than 5 years without aggressive systemic chemotherapy. Radiotherapy in these patients is only indicated when "marginal" or "less than marginal" surgery is expected. In terms of efficacy, radiotherapy is inferior to surgery. In disseminated osteosarcoma, a curative treatment approach will also provide for surgical removal of all metastases. Treatment of primary malignant fibrous histiocytoma (MFH) of bone is identical to osteosarcoma therapy. Since radiotherapy appears to be marginally more effective than in osteosarcoma, both modalities of local therapy are used. Systemic chemotherapy adds an additional benefit for improved survival. Therapy for Ewing's tumor also follows a combined modality approach. The introduction of systemic chemotherapy has raised 5-year survival rates from less than 10% to above 60%. The role of surgery is currently subject to debate. At present, the use of surgery or irradiation for local control is tailored to the individual patient's needs.

Ewing sarcoma: favourable results with combined modality therapy and conservative use of radiotherapy

BACKGROUND

At the Hospital for Sick Children (HSC), we have treated Ewing sarcoma (ES) with multi-agent chemotherapy, surgery and conservative use of radiotherapy for local control. Our objective was to describe the outcome and prognostic factors associated with this strategy.

PROCEDURE

We performed a retrospective chart review of children diagnosed with ES at HSC from Feb 1984 to June 1999.

RESULTS

Seventy-two evaluable children were identified. All received chemotherapy. Local control administered was surgery (n = 37), radiation (n = 23), both (n = 10) or neither (n = 2). The 7-year EFS was 66.4%. Recurrence occurred in 23 patients, 7 locally and 16 distantly. Better EFS was associated with male gender (78.5% vs. 52.1%; P = 0.007), localised disease (77.0% vs. 39.4%; P = 0.0004), extremity primary (88.2% vs. 52.8%; P = 0.005) and non-pelvic primary (75.7% vs. 18.2%; P < 0.0001).

CONCLUSIONS

Favourable outcomes were seen for patients treated with multi-agent chemotherapy, surgery and conservative use of radiotherapy. Metastatic disease rather than local control was the major cause of failure.

Role of radiotherapy in Ewing tumors

BACKGROUND

The objective of this review article is to outline the role of radiotherapy in a curative multimodal treatment concept.

PROCEDURE

We have analyzed the data from major multi-institutional prospective trials in Ewing tumors for to evaluate the impact of radiotherapy on local control and survival.

RESULTS

Surgery yields in general better local control and survival figures as compared to radiotherapy. The efficacy of radiotherapy as compared to surgery varies among the studies and seems to be dependent on patient selection and sequencing with chemotherapy. Combined local therapy (surgery plus post- or pre-operative radiotherapy) has yielded excellent local control rates in patients with high-risk lesions (e.g., pelvic tumors); although not proven by randomized studies, an impact on survival is likely. Indications for post-operative radiotherapy are unradical or marginal resections and poor histological response. In patients with chest wall primaries, adjuvant hemithorax irradiation has reduced the relapse rate significantly. Pre-operative irradiation offers theoretical advantages. Bilateral lung irradiation (as consolidation after chemotherapy) seems to improve prognosis in patients with metastases at diagnosis.

CONCLUSIONS

Patients with high-risk lesions probably benefit from combined local treatment (surgery plus radiotherapy). Improving local control after radiotherapy is a major issue for future studies, and sequencing with chemotherapy seems to be critical factor. The possible curative potential of radiotherapy in metastatic disease requires further investigation.

Treatment of Ewing sarcoma family of tumors: current status and outlook for the future

BACKGROUND

The Ewing sarcoma family of tumors (ESFT) comprises a group of well-characterized neoplasms with aggressive behavior. Despite significant progress with the use of intensive multiagent chemotherapy and local control measures, a significant proportion of patients die of disease progression. Chemotherapy dose intensification and autologous hematopoietic stem cell transplant (HSCT) have been explored by many institutions without obvious benefit in high-risk patients. Our current understanding in the biology and treatment of ESFT suggests that a more rational approach to the development of risk-adapted therapy should be undertaken.

PROCEDURE

We performed a review of the most relevant data regarding the current status in the treatment of ESFT. The results of the major American and European cooperative groups were analyzed, including the treatment strategies used and the prognostic factors identified for both localized and metastatic ESFT.

RESULTS

The intensification of alkylating agents and topoisomerase-II inhibitors is feasible and has resulted in some survival improvement for selected patients. This benefit seems to be restricted to patients with localized disease, and a proportion of survivors are at risk of developing treatment-related hematologic malignancies. Nevertheless, these advances have resulted in a re-definition of prognostic factors, which may help to define risk groups based on tumor load parameters as well as biologic factors (type of fusion transcript and histologic response to chemotherapy). Patients with advanced metastatic disease may benefit from HSCT. New strategies such as immunotherapy and the use of biologic modifiers may have a role in the treatment of ESFT.

CONCLUSIONS

Future treatment for ESFT should consider risk-adapted strategies and the inclusion of newer therapies such as biologic modifiers for the minimal residual disease. A modified risk-adapted therapy is proposed.

Outcome after relapse in an unselected cohort of children and adolescents with Ewing sarcoma

BACKGROUND

Survival after relapse in patients with Ewing sarcoma is very poor and this retrospective study attempts to identify of prognostic factors predicting survival after relapse.

PROCEDURE

A total of 191 patients with localised Ewing sarcoma were registered in the ET-2 trial of the United Kingdom Children's Cancer Study Group (UKCCSG). All patients received standardised primary treatment with chemotherapy and surgery and or radiotherapy as local modality treatment. Sixty-four patients who relapsed are included in this report. Treatment at relapse was variable and included chemotherapy, surgery, radiotherapy and high dose therapy (HDT) or megatherapy with peripheral stem cell transplantation (PBSCT) or autologous bone marrow transplantation (ABMT) in various combinations. A subgroup of patients had only non-specific symptomatic treatment at relapse. Both univariate and multivariate methods were used to investigate variables affecting survival after relapse.

RESULTS

The overall actuarial median survival from relapse for all patients was 14 months (95% CI 11-16 months). Univariate analysis showed that males had a longer survival (median, 16 months vs. 11 months); patients who relapsed while on treatment did worse (median, 3 months vs. 16 months) and patients who had a longer disease-free interval (DFI) prior to relapse had a better outcome (DFI <1 year, median survival = 3 months; DFI 1-2 years, survival = 8 months; DFI > 2 years, median survival = 24 months, P < 0.001). Multivariate analysis confirmed that duration of first remission was the only factor associated with longer survival after relapse.

CONCLUSIONS

These data suggest that although aggressive therapy may delay disease progression after relapse for some children, the course of the disease after relapse is usually fatal. International co-operative studies are needed to evaluate new strategies.

Ewing tumour: incidence, prognosis and treatment options

Ewing tumours, i.e. Ewing's sarcoma and malignant peripheral neuroectodermal tumours, are the second most common primary malignant tumours of bone in childhood and adolescence, with an annual incidence rate in Caucasians of 3 per 1 million children <15 years of age. Histopathologically small blue round cell tumours, Ewing tumours show a typical chromosomal rearrangement in >95% of cases linking the EWS gene on chromosome 22q12 to a member of the ETS transcription gene family, most commonly to Fli-1 on 11q24. This fusion contributes to the malignant potential of Ewing tumour cells, indeed antisense oligonucleotides may prevent tumour growth in vitro. After open biopsy, and histological and possibly molecular biological confirmation of the diagnosis, treatment consists of several months of multidrug cytostatic therapy and local therapy. Both surgery and radiotherapy may control local disease, but without consequent cytostatic chemotherapy all patients will eventually succumb to distant metastases. With the use of alkylating agents including doxorubicin, cyclophosphamide and/or ifosfamide, and other cytostatic drugs such as actinomycin D (dactinomycin), vincristine and etoposide, long-term survival can be achieved in >50% of patients with localised disease. Patients with clinically detectable metastases at diagnosis, patients not responding to therapy and patients with disease relapse have a significantly poorer prognosis. Maximum supportive care and local therapy managed by an experienced physician are required in all patients, and inclusion of high-risk patients in phase I and II studies is warranted. Hence, treatment of patients with Ewing tumours should be performed in experienced centres only and preferably within controlled clinical trials.

Survival after recurrence of Ewing tumors: the St Jude Children's Research Hospital experience, 1979-1999

BACKGROUND

Despite improved therapies, 30-40% of patients with Ewing tumors (ET) experience recurrence and have a poor prognosis. The authors analyzed factors prognostic of survival in patients with recurrent ET.

METHODS

The authors assessed the relation between postrecurrence survival (PRS) and demographic, disease, and treatment factors in 71 patients who experienced recurrent ET after treatment on one of three consecutive institutional protocols.

RESULTS

Thirty-four patients (47.9%) had distant recurrence, 25 patients (35.2%) had local recurrence, and 12 patients (16.9%) had both distant and local recurrence at a median of 1.7 years after diagnosis. The probability of 5-year PRS (+/- 1 standard error) was 17.7%+/-4.5%. Recurrence > or = 2 years after diagnosis predicted a significantly better outcome (5-year PRS, 34.9%+/-8.5%) compared with earlier recurrence (5.0%+/-2.8%; P < 0.001). Patients who had both local and distant recurrence fared worse (5-year PRS, 12.5%+/-8.3%) compared with patients who had local recurrence alone (21.7%+/-7.8%) or distant recurrence alone (17.6+/-6.1%). Among patients with local recurrence alone, those who underwent salvage with radical surgery had significantly higher 5-year PRS estimates (31.4%+/-11.6%) compared with the other patients (9.1%+/-6.1%; P = 0.023). Pulmonary irradiation significantly improved the outcomes of patients with isolated pulmonary recurrence (5-year PRS estimate, 30.3%+/-12.5% vs. 16.7%+/-10.8%, respectively; P = 0.018).

CONCLUSIONS

Although outcomes are generally poor after patients experience recurrence of ET, certain patient groups differ appreciably in their likelihood of survival. Patients who experience recurrence > or = 2 years after diagnosis and patients who have local recurrence that can be treated with radical surgery and intensive chemotherapy have the most favorable outcomes.