Clinicopathologic assessment of postradiation sarcomas: KIT as a potential treatment target.

PURPOSE: Postradiation sarcoma, a sarcoma developing in a previously irradiated field, is a rare tumor. Surgery appears to be the only curative treatment option. In general the prognosis is poor, and new treatments options are needed. One study reported the expression of KIT receptor tyrosine kinase in two postradiation angiosarcomas. Success of inhibition of KIT in malignant gastrointestinal stromal tumors with imatinib mesylate seems mutation-dependent, with a favorable response in the presence of exon 11 mutations. Experimental Design: We performed a clinical, immunohistochemical, and genetic assessment of postradiation sarcomas, including angiosarcomas. Archival tumor tissue was available from 16 patients diagnosed with a postradiation sarcoma between 1978 and 2001. Data on the first and secondary tumor, treatment, and follow-up was documented. KIT expression was assessed by immunohistochemistry. For comparison, 23 spontaneous soft tissue sarcomas of similar histological types were analyzed. Exon 11 of the c-kit gene was analyzed by direct DNA sequencing. RESULTS: Fifteen patients received initial irradiation for malignant disease and 1 patient for a benign condition. The median delivered dose was 50 Gy. The median latency period between irradiation and diagnosis of postradiation sarcomas was 222 months. Histological types included: angiosarcoma, fibrosarcoma, malignant fibrous histiocytoma, osteosarcoma, rhabdomyosarcoma, and unspecified sarcoma. In concordance with the literature, patients had a poor outcome. Only 3 of 16 patients were disease-free 43, 60, and 161 months after being diagnosed of postradiation sarcoma, all 3 having favorable tumor and treatment characteristics. Fourteen of 16 tumor samples were KIT-positive (88%). In 8 cases >80% of tumor cells stained positively. Five of 23 (22%) spontaneous soft tissue sarcomas of comparable histological types, including 2 angiosarcomas, were KIT-positive. Molecular genetic analysis of exon 11 of the c-kit gene was attainable for 13 of the 16 postradiation sarcomas. No mutations were found. CONCLUSIONS: Postradiation sarcomas are aggressive malignancies, seldom amenable to curative treatment. A majority of the analyzed tumors showed extensive expression of the KIT protein, but no mutations in exon 11 of the c-kit gene were found. Still, without the availability of effective therapies, treatment with the KIT inhibitor imatinib mesylate might be considered for patients with postradiation sarcomas.     

Malignant fibrous histiocytoma in bone infarct. Association with sickle cell trait and alcohol abuse

A 42-year-old black man with sickle cell trait and a history of alcohol abuse had a malignant fibrous histiocytoma of the distal femur. The tumor developed in a bone infarct that had been present for at least 54 months. This is the first reported association of malignant fibrous histiocytoma and bone infarct in which the infarct was related to sickle cell trait and alcohol abuse. A detailed map of the sections from the resected femur disclosed a spectrum of cytologic changes in the sarcoma that ranged from bland fibroblasts in the center of the tumor to high-grade sarcoma at the periphery. Awareness of this spectrum has diagnostic importance regarding the potential underdiagnosis of well-differentiated malignant fibrous histiocytoma.     

Malignant (fibrous) histiocytoma of bone--fact or fancy?.

Malignant (fibrous) histiocytoma is currently defined as a malignant primary bone tumor that contains a mixture of fibrogenic cells and cells that are histologically similar but which appear to be histiocytic. In this type of histiocytoma the nuclei are often indented; cytoplasm is usually abundant and may be slightly foamy; nucleoli are often large; and multinucleated malignant cells are usually a prominent feature. Many dedifferentiated chondrosarcomas, osteosarcomas, and fibrosarcomas of bone contain areas that resemble what we regard as malignant (fibrous) histiocytoma. When the entirety of a malignant tumor of bone fits the outlined histologic pattern, the designation of malignant (fibrous) histiocytoma seems appropriate. From 158 fibrosarcomas of bone and 962 osteosarcomas of bone in our files, 35 tumors were segregated because they appeared to be properly designated as malignant (fibrous) histiocytoma. A wide age range was represented by affected patients, and a large variety of bones harbored these tumors. Approximately one-third of patients eligible for 5-year follow-up were long-term, symptom-free survivors. Four deaths occurred from the tumor after more than 5 years, and one patient had radiographic evidence of pulmonary metastasis 7 years after amputation. Radiation therapy has been curative in at least two cases. The correct designation for these tumors in the light of current knowledge is malignant tumor, consistent with malignant (fibrous) histiocytoma.     

Malignant fibrous histiocytoma and pleomorphic sarcoma in association with medullary bone infarcts.

A malignant fibrous histiocytoma arose in the proimal tibia of a 40-year-old man who had multiple, symmetrically distributed, medullary bone infarcts of unknown etiology, involving the distal femora and the tibiae. Despite amputation and chemotherapy, widespread metastases developed and death occurred 19 months after surgery. A polemorphic sarcoma, probably representing an anaplastic malignant fibrous histiocytoma, arose in association with a single medullary infarct in the proximal humerus of a 33-year-old woman. She remains well without evidence of disease five years after treatment by radical radiotherapy followed by shoulder disarticulation. Sarcoma arising in association with bone infarction is a rare entity. Sixteen cases reported in the medical literature, including our own, are reviewed. The sarcomas arose in the tibia in nine cases, the femur in six cases and the humerus in one case. The patients were usually older individuals and 13 of the 16 were male. All but two had multiple bone infarctions. Four of the patients had caisson disease, three had what is probably an hereditary bone dysplasia, one had sickle cell disease and eight had infarcts of unknown etiology. Most patients have had a rapidly fatal outcome. Thirteen of the sarcomas have been fibrosarcomas or malignant fibrous histiocytomas, both of which are rare primary bone tumors. Analysis of the published cases of bone infarction-related sarcomas suggests that the risk of developing a sarcoma is greatest in infarcts with large medullary components.     

Postirradiation sarcoma (malignant fibrous histiocytoma) following cervix cancer

A case of postirradiation sarcoma is described. The tumor, a malignant fibrous histiocytoma, occurred in the radiation field 11 years following postoperative external beam radiation therapy (7000 rad) for carcinoma of the cervix. Reports of postirradiation malignant fibrous histiocytoma are rare, and the occurrence of this neoplasm following treatment of cervix cancer has not previously been described. The literature concerning postirradiation bone and soft tissue sarcomas is briefly reviewed, with special attention to malignant fibrous histiocytomas.     

Current topics in the diagnosis and treatment of malignant fibrous histiocytoma

Malignant fibrous histiocytoma (MFH) is a tumor about which much remains unknown. The cell origin, molecular mechanism of pleomophism and mechanism of pleomorphic change in a cell undergoing malignant change have not been elucidated. MFH-like histological changes are observed in many bone and cartilage sarcomas, and some renal cell carcinomas and malignant lymphomas. These changes occur in many subtypes of sarcomas such as osteogenic sarcoma, chondrosarcoma, leiomyosarcoma, rhabdomyosarcoma, and liposarcoma. MFH has been regarded as one tumor classification from its special histopathological features. In clinical pathological studies these tumors are divided into low-grade fibrous tumors and fibrous histiocytic tumors. With the establishment of molecular biological diagnostic methods, MFH-like histological features can be seen in changes in cellular differentiation of many sarcomas. Patients with MFH often have repeated recurrences before a diagnosis is made, and the tumor is partially resected. Furthermore, distance metastasis develops and the prognosis is poor. The sensitivity of MFH to radiotherapy and chemotherapy is insufficient, and evidence is lacking for adjuvant treatment. Rescue following initial treatment failure is extremely difficult. Local control of 70% to 90% can be achieved if a correct diagnosis is made, and a curative wide resection or salvage wide resection are done early. For treatment of bone and soft tissue sarcoma, a correct diagnosis and initial treatment are extremely important. MFHs are rare tumors that occur in every part of the body. Many cases need to be accumulated in joint clinical studies across fields according to organ and specialty, and effective treatment method developed. We need to advance the standardization of treatment for MFH, and eliminate wrong initial treatment through the active provision of information.     

Cardiac Sarcomas: An Update

Primary cardiac sarcomas are rare and represent 20% of all primary cardiac tumors. Symptoms depend on the chambers and the cardiac structures involved. Transthoracic echocardiography is commonly used to identify a cardiac mass. The diagnosis of cardiac sarcoma requires adequate sampling and the careful use of ancillary diagnostic techniques. In the most recent histologic classification, angiosarcoma is the most common malignant tumor of the heart with recognizable differentiation. Undifferentiated sarcomas account for one-third of all cardiac sarcomas and have been incorporated in the malignant fibrous histiocytoma/pleomorphic sarcoma subgroup. Elective cardiac sarcoma therapy includes complete surgical excision when possible, followed by radio and chemotherapeutic regimen, the latter preferably containing anthracyclines, ifosfamide, or taxanes. Prognosis of cardiac sarcomas is very poor, with mean survival ranging from 9.6 to 16.5 months. A less-aggressive course seems related to the left atrium location, a low histologic grading with scarce cellular pleomorphism and low-mitotic activity, absence of necrosis, myxoid tumor appearance, and absence of metastasis at diagnosis.     

Regional chemotherapy with the use of cisplatin and doxorubicin as primary treatment for advanced sarcomas in shoulder, pelvis, and thigh

Eight patients who had large sarcomas in the hip, thigh, or shoulder girdle have been described. Three had osteogenic sarcomas, and one each had Ewing's sarcoma, biphasic synovial sarcoma, pleomorphic liposarcoma, undifferentiated spindling sarcoma, and malignant fibrous histiocytoma. All eight tumors showed evidence of regression after intraarterial infusion of cisplatin and Adriamycin (doxorubicin) given over 48 hours at 3-week intervals, for a total of between three and seven courses. Tru-cut needle biopsy specimens of five of the lesions were normal after chemotherapy. However, after resection of the regressed fibrotic tumor in seven of the patients, four contained foci of probably viable malignant cells. These cell foci were intraosseous in three cases and in the wall of a cyst in one case. In the remaining case, tumor in the distribution of the infused artery regressed, but tumor in a region supplied by an artery that was not infused continued to enlarge. In one patient with osteogenic sarcoma in the pelvis, despite a good response to intraarterial chemotherapy that was followed by surgical resection and radiotherapy, tumor recurred in an adjacent area in tissues supplied by an artery not infused. A hindquarter amputation subsequently was required. With the exception of the two cases in which adequate tumor arterial infusion was not achieved, local primary tumor control was accomplished by intraarterial infusion chemotherapy followed by local resection or radiotherapy and local resection in all patients. Four patients are well without evidence of residual or metastatic sarcoma 3.5 years after presentation in the case of an osteogenic sarcoma of shoulder, 2.5 years after presentation in the case of a large pleomorphic liposarcoma of thigh and groin, 20 months after presentation in the case of lower-thigh malignant fibrous histiocytoma, and 1 year after presentation in a child with an osteogenic sarcoma of lower femur.     

Radiation-induced sarcoma

Opinion statement Radiation-induced sarcomas can originate in either the irradiated bone or soft tissues. Most of these tumors are high-grade. The most common histologic subtypes are malignant fibrous histiocytoma (MFH) and osteosarcoma, although other histologies (eg, angiosarcoma, rhabdomyosarcoma) can occur. Tumor size and grade are the two most important prognostic factors for soft tissue sarcomas, including those associated with radiation therapy. The therapy is therefore dictated by the risk of distant metastases. High-grade tumors that are larger than 5 cm should be treated with primary chemotherapy followed by a margin-negative surgical excision of the residual disease. All low-grade tumors and high-grade tumors 5 cm or smaller should be treated with a margin-negative surgical excision, and systemic chemotherapy should be considered when a negative margin is difficult or impossible to accomplish. Radiationinduced sarcomas (either MFH or osteosarcoma) originating in bone should be approached with primary chemotherapy followed by a margin-negative excision similar to de novo bone sarcomas. The dose-intensity of the active agents should be adjusted appropriately for the age, performance status, and prior therapy in a given patient.     

Soft tissue sarcomas: Current trends in diagnosis and management

Sarcomas (fleshy tumors) were distinguished from carcinoma (crab leg tumors) at the time of Hippocrates. Sarcomas are related embryologically to leukemias and lymphomas because all are though to be malignancies of mesodermal embryologic origin. Neurosarcomas, however, are an exception, since they arise from tissue of neuroepidermal origin.

Malignant sarcomas of the soft tissue represent an unusual primary malignant tumor. These lesions are characterized by their diversity in the histologic appearance and in their biologic behavior, as well as in anatomical origin. Currently there are approximately 7,400 newly diagnosed bone and soft tissue sarcomas, and approximately 4,200 deaths per year in the United States. The incidence of sarcomas varies by histologic type in various age groups. Embryonal rhabdomyosarcoma in the orbit peaks in the 4-year-old, and in the urinary tract in adolescence. Osteosarcoma has peak incidence in the teenage years, and Ewing's sarcoma develops between the ages of 15 and 30. Other sarcomas such as malignant fibrous histiocytoma and chondrosarcoma generally occur in patients aged more than 55 years. The incidence of osteosarcoma in whites and nonwhites is equal; Ewing's sarcoma is predominantly a disease of Caucasians.

The relatively infrequent occurrence of these tumors plus their diverse histology and diverse presentations have made it difficult for any one institution to have enough patients to directly compare, in a randomized prospective fashion, one treatment with another in order to determine the optimal primary therapy. The purpose of this monograph is to review recent concepts in terms of pathology, surgery, radiation therapy, chemotherapy, and multimodality therapy.     

Primary breast sarcoma: A review of 33 cases with immunohistochemistry and prognostic factors

The clinical and pathological features of 33 previously untreated patients with primary breast sarcoma were retrospectively analysed to evaluate the prognostic significance of histologic variables on survival. The series comprised 17 cystosarcomas phyllodes and 16 stromal sarcomas (excluding angiosarcomas).All tumors were reviewed and classified in similar fashion to extramammary soft tissue sarcomas. In addition, immunohistochemical studies were performed on paraffin sections with a panel of several antibodies directed against cytoskeletal filaments and cellular enzymes; five cases were also examined by electron microscopy.Most tumors were malignant fibrous histiocytoma (21 cases) and fibrosarcoma (6 cases) types. Surgery was the main therapy. Metastasis-free survival rate was significantly correlated only with histological grade, consisting of tumor differentiation, tumor necrosis, and mitotic activity. Courses and survivals of the cystosarcoma and stromal groups were identical, questioning the clinical value of this pathologic distinction. All local recurrence, metastasis, or death occurred within 30 months, though follow-up was much longer.Immunohistochemistry was disappointing for identification of specific histologic sub-types.     

Primary sarcomas of the heart.

Seventy-five primary sarcomas of the heart were classified by histologic appearance as angiosarcoma (26 cases), undifferentiated sarcoma (18 cases), osteosarcoma (9 cases), fibrosarcoma (6 cases), malignant fibrous histiocytoma (6 cases), leiomyosarcoma (4 cases), myxosarcoma (3 cases), synovial sarcoma (2 cases), and neurofibrosarcoma (1 case). The ages of the patients ranged from 1 to 75 years at the time of presentation (mean, 39 years). Angiosarcomas were predominantly right-sided and osteosarcomas left-sided. Forty patients treated surgically were examined, and survival correlated with clinical and histologic parameters. the survival rate was poor, with a mean of 11 months and median of 6 months. By univariate analysis, the survival rate was more favorable for patients with tumors located on the left side of the heart, without necrosis, with a low mitotic count, and without metastasis at diagnosis. Survival rates were better in patients receiving chemotherapy and radiation therapy. Age, gender, presence of differentiation, and histologic type did not affect prognosis. By multivariate analysis, a low level of mitotic activity and any therapy were the only significant factors affecting survival rate. Immunostaining with commercially available antisera was useful in the diagnosis of sarcoma but not in subclassification of 19 tumors so tested. Although the prognosis for patients with cardiac sarcomas is dismal, histologic grading is useful in predicting outcome, as has been shown for soft tissue sarcomas of other sites.     

Postradiation malignant fibrous histiocytoma and osteosarcoma of a patient with high telomerase activities

BACKGROUND: An extremely rare case of postradiation malignant fibrous histiocytoma (MFH) and osteosarcoma (OS) secondary to radiation therapy for leukemia-related osteolytic lesions is presented. In addition, the telomere biology of these tumors was investigated. CASE REPORT: A 14-year-old boy was diagnosed with acute lymphocytic leukemia. The right tibia was irradiated at a total dose of 60 Gy, and the left tibia was irradiated at a total dose of 40 Gy. The left tibia developed MFH and the right tibia developed OS. RESULTS: Telomere reduction (MFH 70.2, OS 70.0%) and high telomerase activities (MFH 12.1, OS 17.7 TPG) were observed. These results reflect an aggressive feature of postradiation sarcomas. CONCLUSION: Prognosis for patients diagnosed with postradiation sarcoma is poor due to its aggressiveness. However, even if sarcoma occurs after irradiation in more than two fields in a single patient, improvements in prognosis are anticipated with appropriate chemotherapies and wide resection.     

Osteogenic sarcoma. Malignant fibrous histiocytoma subtype

A distinctly different entity from the now well-delineated malignant fibrous histiocytoma (MFH) of bone is the MFH histopathologic subtype of osteogenic sarcoma. Although uncommon, recently the authors have encountered six cases of this neoplasm, in each of which the soft tissue component was devoid of bone elements and was microscopically indistinguishable from MFH of bone or soft tissue. Neoplastic osteoid and woven bone were present in the osseous component of each tumor, however. Radiologically, the lesions generally were osteoblastic but focally osteolytic with features typical of osteogenic sarcoma. Pain was the most common presenting symptom. There was no age or sex predilection. Immunocytochemical staining showed strong positivity with alpha-1-antichymotrypsin within malignant bizarre giant cells and occasional neoplastic osteoblasts in five cases. The biological behavior followed a very aggressive course. Four of the six patients developed pulmonary metastases 6 to 12 months after initial surgery; one patient presented initially with pulmonary metastases. Adequate tumor sampling as well as optimal correlation with clinical and radiographic information are required to distinguish the MFH subtype of osteogenic sarcoma from MFH of bone, both being high-grade neoplasms, however.     

Postirradiation malignant fibrous histiocytoma in a patient with squamous carcinoma of the uterine cervix--an autopsy case

An autopsy case of postirradiation sarcoma is described. The tumor, a malignant fibrous histiocytoma, occurred in the radiation fied 7 years after postoperative external beam radiation therapy (6000 rad) for squamous cell carcinoma of the cervix. To our knowledge, 11 cases of postirradiation malignant fibrous histiocytoma have been reported in the literature and only one occurrence of this neoplasm after treatment for cervical cancer has been described. We review the literature on postirradiation sarcoma with special attention to malignant fibrous histiocytoma.     

Doxorubicin and cisplatin chemotherapy in high-grade spindle cell sarcomas of the bone, other than osteosarcoma or malignant fibrous histiocytoma: a European Osteosarcoma Intergroup Study

There are limited data that define the role of chemotherapy in the treatment of high-grade spindle cell sarcomas of bone, other than osteosarcoma or malignant fibrous histiocytoma (MFH-B). This prospective study evaluates the effect of doxorubicin and cisplatin on these tumours. Thirty-seven patients, age 65 years, with spindle cell sarcoma of bone, except osteosarcoma or MFH-B, were included. Chemotherapy consisted of doxorubicin and cisplatin every 3 weeks for six cycles. Resection was performed after three cycles. In 15 patients with metastases, response assessment showed three complete responses (CR), four stable disease (SD), five progression; three were not evaluable. Median time to progression was 30 months (95% Confidence Interval (CI), 8-51 months) for the operable non-metastatic patients; median survival 41 months (95% CI, 16-82 months). Median time to progression in the metastatic group was 10 months (95% CI, 0-18 months) and median survival was 14 months (95% CI, 4-45 months). This study suggests a limited role for doxorubicin and cisplatin in metastatic high-grade spindle cell sarcoma of bone, other than osteosarcoma or MFH-B cases.     

Benign and malignant fibrous histiocytomas of the soft tissues: functional characterization of the cultured cells

Cell cultures were carried out from fresh tumor tissues obtained from seven cases of histiocytic tumors of the soft tissues including four of malignant fibrous histiocytoma, two of benign fibrous histiocytoma, and one of giant cell tumor of tendon sheath. The cultured cells were studied by light and electron microscopy, rosette formation for surface receptors, immune phagocytosis, and enzyme cytochemistry. The culture of each tumor revealed a mixture of histiocyte-like cells, fibroblast-like cells, amd intermediate forms. Bizarre giant cells were numerous in the early cultures of malignant fibrous histiocytoma, but they were absent in the cultures of benign fibrous histiocytoma and giant cell tumor of tendon sheath. In all the seven cases the cultured cells exhibited several features characteristic of histiocytes: (1) surface receptors for the Fc-portion of immunoglobulin G; (2) surface receptors for the third component of complement; (3) immune phagocytosis of opsonized erythrocytes; and (4) lysosomal enzymes including alpha-naphthyl butyrate esterase, and acid phosphatase. These findings suggest that the histiocytic tumors of the soft tissues in discussion actually comprise the cells that have the functional property of histiocyte. The tumor cells in the surgical specimens presented essentially the same ultrastructural and enzyme histochemical characteristics as those of the cultured cells.     

Clinical and prognostic significance of PD-1 and PD-L1 expression in sarcomas

Programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) are new targets in cancer immunotherapy in recent years. The aim of this study is to evaluate the PD-1/PD-L1 expressions in sarcomas and to determine association between PD-1/PD-L1 expressions and clinical/pathological properties in some sarcoma subtypes. Formalin-fixed, paraffin-embedded tissue samples from 65 cases with sarcomas were analyzed. Immunohistochemical staining was performed to detect the PD-1 and PD-L1 expressions in tumor tissue and microenvironment, separately. PD-1 expression in tumor tissue and microenvironment was detected in 11 (17 %) and 8 (12 %) cases, respectively. PD-L1 expression in tumor tissue and microenvironment was detected in 19 (29 %) and 20 cases (30 %), respectively. None of the 5 Ewing sarcomas involving bone showed PD-1/PD-L1 expression, while 2 of 3 cases with Ewing sarcomas involving soft tissue showed PD-1 and PD-L1 expression. Among 5 cases with Kaposi sarcoma, four showed PD-1 and/or PD-L1 expression in tumor or microenvironment. PD-1/PD-L1 expressions were detected 3 of 6 cases with pleomorphic sarcoma, 2 of 4 cases with peripheral nerve sheath tumors and 1 of 4 cases with synovial sarcoma. Interestingly, strongest PD-1/PD-L1 expressions in our study group were detected in 2 sarcoma cases with the history of giant cell tumor. PD-1 and PD-L1 expressions are up to 30 % of the cases with sarcomas. It may be rational to target programmed death pathway in Kaposi sarcoma, pleomorphic sarcoma and peripheral nerve sheath tumors. Strong expression of PD-1/PD-L1 in cases with previous giant cell bone tumor has been found to be interesting and must be studied in giant cell tumor samples.     

Prognostic significance of grading and staging systems using MIB-1 score in adult patients with soft tissue sarcoma of the extremities and trunk

BACKGROUND: The predictive value of histologic grading and staging systems for overall survival in different types of adult soft tissue sarcoma of the extremities and trunk is unclear. METHODS: Histologic slides from 193 patients with primary tumors were reviewed for diagnosis, and Ki-67 (MIB-1) immunostaining was performed for grading in all patients. Univariate and multivariate analyses were conducted to analyze the results from patients with soft tissue sarcomas as a group and among the six main histologic categories: malignant fibrous histiocytoma (n = 49 patients), liposarcoma (n = 48 patients), synovial sarcoma (n = 30 patients), spindle cell sarcoma (n = 24 patients), small round cell sarcoma (n = 15 patients), and others (n = 27 patients). The median follow-up was 50 months. RESULTS: Univariate analysis of soft tissue sarcomas showed that tumor size and depth, histologic type, MIB-1 score, grades based on three criteria (tumor differentiation/histologic type, necrosis, and either mitosis or MIB-1 score) and disease stage, as assessed by tumor size, depth, and grade, were associated with overall survival. Among these variables, grading and staging systems using the MIB-1 score had better predictive value compared with the MIB-1 score and standard grading and staging models in the main histologic categories. Because survival curves for the different tumor grades and stages showed similar trends between the different histologic types, multivariate analysis was conducted adjusting for age, gender, disease site, surgical margin, tumor size and depth, grade, stage, and histologic type. Consequently, Grade 3 emerged as the most significant adverse prognostic factor. Additional adverse prognostic factors were Stage III, Grade 2, a histologic type of spindle cell sarcoma, and patient age > 50 years at the time of presentation. The histologic type liposarcoma was identified as a favorable prognostic factor. CONCLUSIONS: The current results indicate that grading and staging systems using the MIB-1 score are very strong prognostic factors in patients with the main histologic types of soft tissue sarcoma. Specific assessment of histologic type should be carried out before deciding on treatment strategies.     

Bone sarcomas as second malignant neoplasms following childhood cancer

This study explores the relationship between histologic variants of bone sarcomas and previous therapy in patients in whom an unrelated malignant neoplasm had been diagnosed during childhood. Sarcomas of bone were the most common second malignant neoplasm (SMN) reported to the Late Effects Study Group, a 13-institution consortium consisting of pediatric oncology centers from western Europe, Canada, and the United States. The authors attempted to relate the histologic subtypes of the 91 bone tumors to clinical factors such as previous therapy and genetic predisposition because morphologic variants have been shown to have biologic significance in other tumors and may have etiologic import. The literature concerning the subtypes of bone tumors, clinical and experimental, is also reviewed. The authors also investigated the effect of several factors on the time interval from the first diagnosis to the SMN (i.e., the bone sarcoma). Anthracyclines significantly shortened the interval by about 3 years. The primary diagnosis also significantly affected the interval, with leukemia/lymphomas having the shortest interval and retinoblastoma the longest. The authors could not demonstrate any significant relationship between morphologic characteristics of the osteosarcoma and predisposing conditions. However, lesions diagnosed as chondrosarcoma and malignant fibrous histiocytoma occurred almost exclusively in patients who had received radiation therapy to the site in which the SMN developed.