Radiation in bone sarcomas: a re-evaluation in the era of intensive systemic chemotherapy

Bone sarcomas

The literature on radiotherapy for sarcomas originating in bone is limited, and the disease is uncommon. Consequently, this review is based on only 28 scientific articles, including 6 randomized studies, I prospective study, and II retrospective studies. These studies involve 1,394 patients. Radiotherapy is of limited value for treating the primary tumors of osteosarcoma. The effects of prophylactic lung irradiation for treating osteosarcoma are unconfirmed. Radiotherapy represents an integrated component of primary treatment for Ewing's sarcoma, but different fractionation schedules should be assessed. Radiotherapy is of limited value in the treatment of chondrosarcoma.

Bulk disease as the major problem in the cure of paediatric sarcomas

Bulk disease is a problem in all the major paediatric sarcomas. It is the pre-eminent problem in parameningeal rhabdomyosarcoma but only a recently recognised problem in limb osteogenic sarcoma (only since the advent of limb-conserving surgery). In all cases where a large bulk of sarcoma threatens to relapse locally, multimodality therapy (surgery, radiotherapy, chemotherapy) stands a better chance of sterilisation than individual modalities of therapy, and such multimodality therapy stands its best chance when it is used early, that is, all three modalities are used at the beginning or shortly after commencement of the treatment course.

Prognostic factors in the treatment of Ewing's sarcoma. The Ewing's Sarcoma Study Group of the German Society of Paediatric Oncology CESS 81

From 1981 up to February 1985, a total of 93 protocol patients entered the study CESS 81. The protocol recommended an initial 18-week period of polychemotherapy (VACA) followed by local therapy and two additional cycles of chemotherapy. Local therapy consisted either of radical surgery or of incomplete resection plus postoperative irradiation with 36 Gy or of radiotherapy alone (46 and 60 Gy). Centrally located lesions were always irradiated with 60 Gy. This article summarizes the data after 5 years. Data of 93 patients were analysed in October 1986 after a median follow-up of 37 months. The projected 5-year survival is 50%. The relapse rate was 42%, distant relapses occurred in 19%, local (plus distant) relapses in 23%. Most of the relapses occurred during the first 3 years of observation. Failure rate was high in patients undergoing irradiation alone (44%). Initial tumour mass (greater than 100 ml) and histopathologic response to initial chemotherapy were identified as major prognostic factors. Tumour site and type of local therapy were not significant if patients were categorised by tumour volume. In small lesions, surgery and radiotherapy were equally effective. In large lesions greater than 100 ml volume, a trend towards a better prognosis in surgically treated patients was observed. The results of CESS 81 emphasize the importance of permanent local control in Ewing's sarcoma even in the presence of systemic control by an effective multi-drug chemotherapy.

Ewing's sarcoma of a lower extremity in an infant. A therapeutic dilemma

A 5.5-month-old infant with Ewing's sarcoma of the left femur is described. The clinical and the pathologic features in this infant are presented in detail, and the dilemma faced in diagnosis and therapy of Ewing's sarcoma in infants is discussed. It is suggested that Ewing's sarcoma in an infant with a lower extremity lesion may be adequately managed without primary amputation.

Radiotherapy of non-metastatic ewing sarcoma

Comparing the radiotherapy data of two groups of patients with non-metastatic Ewing sarcoma, we came to the following conclusions: intensive chemotherapy does not substitute for effective radiotherapy. Irradiation fields should be large enough to include the whole affected bone and the entire extra-osseous compartments, exempting only uninvolved epiphyses. Marginal recurrences are a major risk of the shrinking field technique. Single doses per fraction should be high and the total dose raised to the point of maximal irradiation tolerance of normal tissues.

Local therapy of rhabdomyosarcoma, osteosarcoma and Ewing's sarcoma of children and adolescents

Local control of the primary tumour is a fundamental requirement for clinical cure. Towards this aim, the primary tumour must be diagnosed early and identified histologically. The size, extension, and spread within the patient must be defined precisely. In planning effective local therapy, additional questions must be answered including resectability, mutilation, sensitivity to radio- and chemotherapy, anticipated morbidity from therapeutic measures, etc. For osteosarcoma there is no reasonable alternative to radical surgery. Because of the 20% local recurrence rate of Ewing's sarcoma following radiotherapy, radical surgical removal of the primary tumour should be attempted whenever possible. For rhabdomyosarcoma, particularly for its embryonal histology, non-radical removal of the primary sarcoma is still compatible with a cure, provided adequate radio- and chemotherapy is also administered. Primary irradiation is indicated in radiosensitive unresectable primary tumours and may convert these into an operable state. Chemotherapy is the domain of prevention and treatment of metastatic disease. It has, however, also a proved effect on primary tumours and, in several recent protocols, precedes local therapy.

The value of adjuvant chemotherapy in the management of sarcomas in children

Sarcomas of childhood rank fifth in incidence of malignant tumors in children younger than 15 years. Among the soft tissue sarcomas, approximately 50% are rhabdomyosarcomas. The remainder represent a heterogeneous group of diverse sarcomas which are not unique to children and include fibrosarcoma, synoviosarcoma, malignant fibrous histiocytoma, malignant schwannoma, angiosarcoma, leiomyosarcoma, and others. The most common bone cancers in childhood are osteosarcoma and Ewing's sarcoma. Although a multidisciplinary approach utilizing surgery, irradiation, and combination chemotherapy is routinely used in management of virtually all children with solid tumors, the value of adjuvant chemotherapy in select bone and rare soft tissue sarcomas is currently being tested. Multiagent chemotherapy including vincristine, dactinomycin, cyclophosphamide, and Adriamycin (doxorubicin) contribute to cure rates in 65% to 75% of children with localized rhabdomyosarcoma, Stages I to III, when combined with surgery and/or irradiation. Other drugs which hold promise include platinum, DTIC, methotrexate, and VP-16. The efficacy of similar drugs in the rarer pediatric soft tissue sarcomas other than rhabdomyosarcoma and its variants requires prospective randomized trials evaluating histologic grade, tumor size, and nodal status. It has been suggested that the high-grade sarcomas presenting with minimal tumor bulk are most sensitive to combined radiotherapy-chemotherapy, whereas the low-grade sarcomas are more resistant to such therapy. Tumor cell heterogeneity contributes to biologic diversity and response to treatment. Chemotherapy as adjuvant therapy to irradiation is currently recommended and utilized for Ewing's sarcoma with survival rates approaching 80%, and disease-free survival of approximately 75% for those with localized disease. Children with widespread and metastatic disease at presentation fare less well. Although multiple single agents exhibit response rates ranging from 40% to 60%, including cyclophosphamide, Adriamycin, dactinomycin, BCNU, mithramycin, and 5-fluorouracil, new and more effective agents are needed. Controversy regarding the value of multiagent chemotherapy in osteosarcoma has stimulated prospective randomized trials. Evaluation of local control rates as well as sites and occurrence of metastases are essential in assessing the contribution of aggressive combined modality therapy in the pediatric sarcomas. Emphasis on refinement of therapy in determining the risk/benefit ratio from adjuvant chemotherapy in pediatric sarcomas is mandatory. Enhancement of early local reactions is apparent when adjuvant chemotherapy is used with local radiotherapy.(ABSTRACT TRUNCATED AT 400 WORDS)

Current status of high linear energy transfer irradiation

Based on laboratory investigations, high linear energy transfer (LET) particle irradiation is capable of more efficient cell kill than that associated with conventional or low LET irradiation. The advantages of high LET irradiation include: (1) a greater ability to damage hypoxic cells; (2) a lesser ability for repair of sublethal and potentially lethal radiation-induced damage; (3) less variation in radiation sensitivity relative to the cell cycle; and (4) a greater ability to deposit the radiation dose in the region of the tumor as opposed to the normal surrounding tissue (neutrons do not have this advantage compared to other particle therapy). Despite these laboratory advantages, it has been difficult to demonstrate any advantage of high LET irradiation in the clinic. A number of new developments have occurred to test the role of high LET: (1) sophisticated technology to enable treatment delivery with higher dose rate and improved depth dose; (2) the construction of hospital-based facilities; and (3) the development of randomized studies involving diseases in which the risk of early metastasis is minimized. It is hoped that careful study in the clinic over the next decade will elucidate the role of high LET particle therapy.

Use of absorbable mesh to displace bowel and avoid radiation enteropathy, during therapy of pelvic Ewing's sarcoma

The use of absorbable polyglactin 910 mesh (Vicryl) is described in a case of Ewing's sarcoma of the pelvis. An operation was performed to hold the small bowel and colon out of the pelvis for a temporary period during which radical radiotherapy was delivered. The mesh allowed the temporary displacement of bowel and obviated bowel radiation morbidity.

Intensive systemic chemotherapy in localized Ewing's sarcoma in childhood. A historical trial

To assess the value in Ewing's sarcoma of a new multiagent therapy (vincristine, cyclophosphamide, Adriamycin, (doxorubicin) procarbazine), 30 children with a localized tumor (eight distal, nine proximal, 13 central lesions) treated at the Institut Gustave-Roussy between 1973 and 1976 (E3), were pair-matched by site of primary with 30 control patients treated without intensive chemotherapy between 1967 and 1972 (E1) at the same institution, both groups having the same local radiotherapy. Actuarial survival and disease-free survival rates at six years were significantly higher in E3 at P less than 0.01, respectively, 58% and 49% versus 25% in E1. The prognostic value of the primary site was ascertained only in children under chemotherapy. In this group there were six early relapses with death within 14 months and nine late relapses at 21 to 38 months. Among these nine patients, six died, one is living with disease, and two are currently alive in second remission. Fifteen patients are continuously free of disease 50 to 90 months after first treatment (median, 69 months): functional sequelae are minimal in six, moderate in seven, and severe in two children with limb amputation. It is concluded that in future treatments chemotherapy must be intensified and begun prior to local treatment which has to be reevaluated for radiation modalities and for radical surgery indication.

Ewing's sarcoma: A combined approach in the management

Twenty-seven histologically confirmed cases of localised Ewing's sarcoma were treated by two different regimes. Radiotherapy alone was used in 13 cases and a combination of chemotherapy and radiotherapy in 14. Single agent chemotherapy (cyclophosphamide) was given sequentially in nine patients and cyclophosphamide and actinomycin-D in five. There is a significant difference in the response to these different regimes. Only 69.2% of patients treated by radiotherapy alone were disease-free, for a median period of 10.4 months and metastases were noticed in 53.8% of cases. The disease-free survival in patients treated by combination therapy (radiotherapy and chemotherapy) was 18.4 months and metastases were seen in only 42.9%. However, no metastases were seen in patients who received cyclophosphamide and actinomycin-D, during a period of 14 months and only one patient showed residual disease. It is concluded that the addition of cyclophosphamide alone is not adequate in the management of Ewing's sarcoma. Actinomycin-D in addition to cyclophosphamide has improved the disease-free survival period significantly. The optimum dose of radiotherapy and its combination with other chemotherapeutic agents needs further trials to find the best and most suitable schedule.

Radiotherapy and combination chemotherapy in advanced Ewing's Sarcoma-Intergroup study

Forty-four patients with metastatic (36 patients) and advanced regional (eight patients) Ewing's sarcoma were treated on a protocol employing intensive combination chemotherapy and radiotherapy to all sites of overt disease (primary site and metastatic sites). Thirty-one patients achieved a complete remission, eight achieved a partial remission, and five patients did not respond to treatment. Of the 31 patients who achieved a complete remission (12 had metastases and six had regional spread), 18 remained disease-free with a median follow-up of 34 months, while recurrences occurred in nine patients. Four patients died of complications of treatment. Although late relapses can still be expected, it appears that intensive multimodal management in metastatic Ewing's sarcoma can produce prolonged disease-free survival and possibly cure in a significant percentage of patients.

Osteosarcoma of the hand

Two cases of osteogenic sarcoma in the hand are reported, with a discussion of the literature.

Ewing sarcoma: treatment with high dose radiation and adjuvant chemotherapy

Twenty-one patients with pathologically proven Ewing sarcoma without overt metastases at diagnosis were treated with a protocol designed by the Royal Marsden/St. Bartholomew's Hospitals Children's Solid Tumour Group (CSTG). They received megavoltage radiotherapy to the involved bone and adjuvant chemotherapy with a combination of four cytotoxic drugs. Seven patients have so far relapsed, four at the original site and three in other bones. The other 14 are clinically free of disease a median of 36 months from diagnosis. Comparison with a historical control group of 19 patients treated with surgery or radiotherapy, but without initial chemotherapy, shows a significant improvement in survival for the study group (P = 0.03). Seventeen of the controls have died. The treatment regime was moderately toxic, but there were no treatment-related deaths. These results confirm that an improved survival time and hopefully cure rate can be expected from treating Ewing tumour with high doses of megavoltage radiation and combination chemotherapy. Future goals must be the better control of large primary lesions and the eradication of micrometastases in other bones. The place of surgery should be re-evaluated in the treatment of the primary tumour, and better adjuvant chemotherapy regimes are needed.