Molecular diagnosis and gene therapy in musculoskeletal tumors

Significant progress has occurred in the molecular analyses of bone and soft-tissue tumors, and genetic studies have led to the development of important new diagnostic tools for the clinical management of patients with sarcomas. The detection of fusion genes induced by tumor-specific translocations, such as EWS-FLI1 in Ewing's sarcoma, SYT-SSX in synovial sarcoma, and CHOP-FUS in myxoid liposarcoma, is becoming significant for clinical diagnosis, because these sarcomas are often indistinguishable from other bone and soft-tissue tumors. Gene therapies with several gene transfer systems have been employed for some incurable cancers. It has been demonstrated that a Herpes simplex virus thymidine kinase (HSV-tk) gene can convert certain nucleoside analogs, such as ganciclovir, which disrupt DNA synthesis and are toxic to nucleosides. Human chondrosarcoma cells transduced with the HSV-tk gene were more sensitive to the cytotoxity of ganciclovir than non-transduced cells. Coculture of chondrosarcoma cells with and without the HSV-tk gene showed a bystander effect. The local injection of gene transduced cells into the chondrosarcoma implanted in nude mice markedly reduced tumor size after the administration of ganciclovir. These results suggested the possibility of gene therapy for chondrosarcoma.     

Current management of chest-wall tumors

Chest-wall resection can be performed with low morbidity and mortality rates and remains the primary treatment for most chest-wall tumors. However, some lesions are best treated with a multimodality approach including preoperative chemotherapy. Therefore, pretreatment tissue diagnosis is essential in planning. The biopsy should be done at the medical center where the definitive treatment will be undertaken, and frequently, a needle biopsy will be sufficient. Osteosarcoma, rhabdomyosarcoma, Ewing's sarcoma, and other small-cell sarcomas are sensitive to chemotherapy, which should be given preoperatively, continued postoperatively, and modified according to the tumor response. Chondrosarcomas and most adult soft-tissue sarcomas are well controlled by primary excision and selective use of adjuvant irradiation. Better systemic and local therapy is needed for the recurrent soft-tissue sarcomas and the aggressive unclassified sarcomas. Chest-wall resection continues to play a primary role in the management of locally and regionally recurrent breast cancer but is best combined with systemic chemotherapy. Chest-wall resection can provide a long disease-free survival in patients with isolated metastases from sarcomas or carcinomas. In addition, significant palliation can be afforded patients with symptomatic chest-wall metastases and a shortened life expectancy.     

Sacral infiltration in pelvic sarcomas: joint infiltration analysis II

The incidence and characteristics of sacral infiltration in pelvic sarcomas were analyzed. Fifty-one patients with a pelvic sarcoma (chondrosarcoma, 15 patients; Ewing's sarcoma, 23 patients; and osteosarcoma, 13 patients) abutting the sacroiliac joint had surgical treatment. Tumor infiltration into the sacrum was suspected based on preoperative images in 18 patients; 15 of 18 patients had histologic tumor invasion. There was a significant difference of median volume of sarcomas with and without infiltration. One of 23 Ewing's sarcomas, seven of 15 chondrosarcomas, and seven of 13 osteosarcomas penetrated the sacroiliac joint into the sacrum. Logistic regression test showed that diagnosis was the most important factor influencing sacral infiltration. Twelve tumors infiltrated through the posterior part of the joint, two tumors infiltrated through the anterior part, and one large tumor infiltrated through an unknown route. To obtain wide surgical margins, patients at risk (elderly, large tumor, or diagnosis of osteosarcoma or chondrosarcoma) for sacral involvement may require extended internal hemipelvectomy with the medial margin extending into the sacrum. High quality imaging studies should be used to assess the need for transarticular resection.     

The role of intraoperative radiotherapy in oncological pediatric surgery

Conventional external beam radiation has proved its profit in pediatric tumors; but its complications have limited it in therapeutical approach. Intraoperative radiotherapy delivers a high single dose in residual tumor or high risk areas during surgery. In our center, during last two years, 7 patients have been candidates to surgery with intraoperative radiotherapy (the age range was between 5 months-17 years; mean 8.5 years). Two patients were excluded of our protocol because of their intraoperative stage. Patients tumors types were: neuroblastoma (n = 3; stage III and IV), soft tissue sarcomas (n = 1) and Ewing's sarcoma (n = 1). The radiation doses ranged from 500 cGyto-1200 cGy. Local control tumor was achieved in 4 patients and no-complications were present secondary to surgery or intraoperative radiotherapy. Intraoperative radiotherapy seems to be a feasible treatment which might promote local control in pediatric tumors with protection of normal tissues and could be an excellent complement in special cases.     

Peripheral primitive neuroectodermal tumor after radiotherapy

A 41-year-old man had a peripheral neuroectodermal tumor develop at the distal third of the fibula 4 years after radiotherapy for relapsed villonodular synovitis. This type of sarcoma usually is classified into the heterogeneic group of small round-cell bone tumors as a subdivision of Ewing's sarcomas. The immuno-staining positivity of the neoplastic cells for the neuron-specific enolase allowed the authors to make the diagnosis of a tumor with neuroectodermal origin. When the histologic study confirmed the diagnosis, the patient was treated with chemotherapy, surgical excision of the tumor, and adjuvant radiotherapy. Radiotherapy is thought to be involved in the genesis of osteogenic sarcomas as it has been shown in several reports, but there is no evidence in the literature of a peripheral neuroectodermal tumor developing after radiotherapy.     

Osteosarcoma and other neoplasms of bone. Magnetic resonance spectroscopy to monitor therapy

Fourteen patients with malignant tumors of bone (ten osteogenic sarcomas, one Ewing's tumor, one giant-cell tumor, two non-Hodgkin's lymphomas), plus one patient with a synovial cell sarcoma, who had been treated by standard extremity-conserving chemotherapy regimens, were examined before treatment by means of localized phosphorus 31 magnetic resonance spectroscopy. Thirteen (86%) of 15 examinations were successful, and 100% of successful examinations showed metabolic abnormality in the tumor. Tumors contained excess adenosine triphosphate and inorganic phosphate, an unusual peak of phosphomonoester, consistent with excessive glycolysis in tumors. The intratumor pH was normal in the 12 bone tumors, but acidic in the single soft-tissue sarcoma (pH 6.8). Metabolic response was observed in all seven patients monitored during chemotherapy, with the earliest examinations being performed two days after first treatment. An increase in the inorganic phosphate level, loss of adenosine triphosphate, and loss of phosphomonoester indicated tumor response; loss of all abnormal metabolites (two of seven patients) indicated regression of the tumor. Tumor relapse was accompanied by reappearance of abnormalities in the magnetic resonance spectrum. Phosphorus 31 magnetic resonance spectroscopy offers a unique means of determining the early response of these malignant tumors to therapy as well as predicting their relapse.     

Sarcoma and the spinal column

Primary sarcomas are rare in the spine. Common primary sarcomas include osteosarcoma, Ewing's sarcoma, chondrosarcomas, and retroperitoneal soft-tissue sarcomas. These tumors tend to occur in adolescents and young adults. Surgery remains the mainstay of treatment, although the anatomy of spine and spinal cord often limits complete surgical resection with a wide margin. Chemotherapy and radiation therapy have variable effects on these tumors. With recent advances in surgical techniques and development of new chemotherapy protocols, survival and local control are both improving.     

Diagnosis and treatment of soft-tissue tumors

The diagnostic and therapeutic management of patients with soft-tissue tumors would be similar to the approach used for bone tumors if it were not for one crucial factor: the absolute necessity to recognize a sarcoma. The predominant features are the size of the tumor and its superficial or deep localization. If the tumor is small and superficial, biopsy can be associated with immediate resection without risk of dissemination to the deep tissues: this is the biopsy-resection approach. If the tumor is deep or superficial but large sized, search for locoregional spread with MRI is necessary before undertaking any surgical procedure. MRI can help guide the biopsy and plan resection if the tumor is a sarcoma. A first biopsy is necessary to establish the histological diagnosis and elaborate the therapeutic strategy. Samples should be sent immediately to the pathology lab which should examine sterile fresh tissue. Experience has demonstrated that proper rules for diagnosis and treatment are not necessarily applied initially in approximately one-fourth of all subjects with a malignant soft-tissue tumor. Besides the medical problems caused by this situation, the patient loses a chance for cure. When the tumor is a sarcoma, surgery is the basis of treatment. Complementary radiation therapy may be necessary, particularly for high-grade tumors or if the surgical margin was insufficient. Systemic or locoregional chemotherapy can also be used for high-grade or non-resectable tumors.     

Peripheral primitive neuroectodermal tumor -- PNET

The authors describe three cases of peripheral primitive neuroectodermal tumor. The tumor was found in soft tissues of the crus, shoulder girdle and perineum, and was also located paravertebrally and epidurally at the level of L1-L2 vertebrae. Radiological findings were not specific for this disease. The results of imaging methods (sonography, CT, MRI, DSA) were important for the assessment of tumor size, its boundary and invasion of the surrounding tissues, and for the evaluation of tumor response to therapy and detection of recurrent disease. The PNET diagnosis was based on immunohistochemical, biochemical and cytogenetic examinations. One patient died 5 months after the first clinical signs were manifested; the two patients surviving for 2 and 1 3/4 years after first sign manifestation, respectively, remained in the care of cancer specialists. Key words: skeletal Ewing's sarcoma, extra-skeletal Ewing's sarcoma, Ewing's sarcoma family of tumors, peripheral primitive neuroectodermal tumor.     

CR、CT、MRI在骨肿瘤诊断中的临床价值

[目的]评价计算机X线摄影（CR）、CT、磁共振成像（MRl）在骨肿瘤诊断中的临床价值。[方法]回顾分析55例经病理证实的影像学资料，其中55例均有CR平片，21例CT扫描，20例做了MRI检查。[结果]55例中51例CR片清晰显示骨质改变，40例CR片清晰显示病灶边界，20例CR片清晰显示骨膜反应，19例CR片清晰显示病灶内有大小不一钙化。21例行CT扫描病例均清晰显示骨质改变、病灶边界、病灶内有大小不一钙化，8例清晰显示骨膜反应。20例做了MRI检查病例均清晰显示病灶边界及软组织肿块，8例显示相应骨髓水肿。[结论]CR片仍为骨肿瘤的首选检查方法，CT较好显示了肿瘤的范围及细微结构，MRI对显示肿瘤的范围、软组织肿块及相应骨髓水肿有明显优势。三者相结合有助于骨肿瘤的诊断。     

The cellular biology of bone tumors

New knowledge in cell and molecular biology has begun to expand the understanding of the biology of osteosarcoma and Ewing's sarcoma. Studies on osteosarcomas have revealed abnormalities in the growth-inhibiting retinoblastoma gene, which may release cells from normal growth control. Abnormalities in growth factor production or response tend to inappropriately activate cell growth. Tumor cell DNA content and cytogenetics may affect the diagnosis and prognostic grouping of osteosarcomas. In Ewing's sarcomas, a characteristic translocation between Chromosomes 11 and 22 has been identified; this translocation is also found in malignant neuroepitheliomas. A variety of studies point to both neuroectodermal and mesenchymal origins for Ewing's sarcomas. Applications of new biologic knowledge and technology to clinical problems will lead to significant changes in the diagnosis, and perhaps in the treatment, of these tumors in the coming years. Collaborations between community and referral center physicians and scientists are critical for continued progress.     

Use of anti-skeletal muscle antibody from myasthenic patients in the diagnosis of childhood rhabdomyosarcomas

Rhabdomyosarcoma (RMS), a common soft tissue tumor in children, may often be difficult to distinguish from Ewing's sarcoma, neuroblastoma, and malignant lymphomas. Confirmation of the skeletal muscle origin of RMS depends partly on the demonstration of striations in tumor cells that are usually undetectable in poorly differentiated tumors. A number of tissue markers (e.g., myoglobin and desmin) are currently being used to establish the origin of RMS. However, most of these markers lack specificity and have relatively low sensitivity. We have investigated the specificity and sensitivity of anti-skeletal muscle antibody (ASMA) from patients with myasthenia gravis in the diagnosis of childhood RMS. Out of eight cases of childhood RMS (four embryonal and four alveolar) examined, two showed striations with hematoxylin and eosin and four with phosphotungstic acid hematoxylin. Myoglobin was detected in five tumors; only well-differentiated tumor cells contained myoglobin. Anti-desmin antibody and ASMA reacted with cells in all the eight tumors whether or not the tumor cells were well differentiated. Anti-skeletal muscle antibody did not react with nine lymphomas, four Ewing's sarcomas, four neuroblastomas, four osteogenic sarcomas, four lipomas, eight duct carcinomas of the breast, and eight squamous cell carcinomas of the lung. Eight leiomyomas and four leiomyosarcomas of the uterus were compared for their reactivity with anti-desmin antibody and ASMA. All the tumors stained with anti-desmin antibody and none with ASMA. The results show that ASMA is useful in the diagnosis of childhood RMS and is a more sensitive reagent than anti-myoglobin antibody. Unlike anti-desmin antibody, it can distinguish skeletal muscle tumors from smooth muscle tumors.     

Positronenemissionstomographie (PET) zur Diagnostik und zum Therapiemonitoring bei urologischen Tumoren

Positron emission tomography (PET) using ((18)F)2-fluoro-D-2-desoxyglucose (FDG) has been shown to be a highly sensitive and specific imaging modality in the diagnosis of primary and recurrent tumors and in the control of therapies in numerous non-urologic cancers. It was the aim of this review to validate the significance of PET as a diagnostic tool in malignant tumors of the urogenital tract. A systematic review of the current literature concerning the role of PET for malignant tumors of the kidney, testicles, prostate, and bladder was carried out. The role of FDG PET for renal cell cancer can be seen in the detection of recurrences after definitive local therapy and metastases. The higher sensitivity of PET in comparison to other therapeutic modalities (CT, ultrasound, MRI) in recurrent and metastatic renal cell cancer suggests a supplemental role of this diagnostic procedure to complement other imaging modalities.The clinical value of PET is established for the identification of vital tumor tissue after chemotherapy of seminomatous germ cell tumors. This diagnostic method has little significance for primary tumor staging and diagnosis of non-seminomatous germ cell tumor because of the high probability of false-negative results in adult teratomas. FDG PET is not sensitive enough in the diagnosis of primary or recurrent tumors in prostate or bladder cancer. Also PET did not prove to be superior to conventional bone scintigram in the detection of mostly osteoblastic metastases in prostate cancer. The recent use of alternative tracers, which are partly not eliminated by urinary secretion (acetate, choline) has increased the sensitivity and specificity of PET also in this tumor entity so that further clinical investigations are needed to validate these technical modifications in their significance for this imaging modality. PET appears to be sufficiently evaluated only for the diagnostic follow-up of patients with seminomatous germ cell tumors after chemotherapy to regard it is the diagnostic tool of first choice. For all other tumors of the urogenital tract this proof is still awaited.     

Ewing's sarcoma and the development of secondary malignancies

The multimodality treatment approach for patients with Ewing's sarcoma during the last decades has dramatically improved patient long-term survival. With improved survival, late consequences and morbidity associated with treatment have become apparent. Among the morbidity associated with treatment is the increased risk of development of secondary malignancies. Therefore, the purpose of the current study was to define the outcome of patients who had secondary malignancy develop subsequent to the diagnosis and treatment of Ewing's sarcoma. Of the 397 patients treated for Ewing's sarcoma at our institution during the past 25 years, 26 patients (6.5%) had 29 secondary malignancies develop. The mean age of the 13 males and 13 females averaged 16 years (range, 6-51 years), and the interval from the diagnosis of the Ewing's sarcoma to the development of the secondary malignancy averaged 9.5 years (range, 1-32.5 years). The secondary malignancies included eight hematopoietic cancers, 12 sarcomas, and nine carcinomas. Although carcinomas most likely represent the general risk of developing cancer in the healthy population, the sarcomas were caused by radiation therapy and the hematopoietic tumors caused by chemotherapy. The latter occurred at a mean latent period of 4.8 years (range, 1.7-12.9 years), and the sarcomas occurred after a mean of 10.9 years (range, 1.5-32.5 years). At the mean followup of 15 years (range, 2-33 years) from diagnosis of Ewing's sarcoma and at a mean followup of 5 years (range, 0.5-28 years) from diagnosis of the second malignancy, 14 patients are alive (43%); however, patients with either sarcomas or hematopoietic secondary malignancies had not only a significantly shorter interval from secondary malignancy to followup (3.3 and 1.2 years, respectively, versus 7.3 years), but also a more dismal prognosis (eight of 12 or six of eight patients died, respectively, versus one of nine). Although the risk of having secondary malignancy develop after the treatment of a Ewing's sarcoma may be only slightly greater than the risk compared with other childhood cancers, patients with hematopoietic and radiation-induced secondary malignancies have a detrimental prognosis. Patients with Ewing's sarcoma need to be followed up carefully and frequently.     

Validation of radiographic response evaluation criteria of preoperative chemotherapy for bone and soft tissue sarcomas: Japanese Orthopaedic Association Committee on Musculoskeletal Tumors Cooperative Study

BACKGROUND: The radiographic evaluation of the response to preoperative chemotherapy for bone and soft tissue sarcomas is based mostly on the change in primary tumor size before and after chemotherapy, as is done for many solid cancers. Its prognostic correlation, however, has hardly been validated. METHODS: We conducted a retrospective validation study of the Japanese Orthopaedic Association (JOA) radiographic response evaluation criteria of preoperative chemotherapy for bone and soft tissue sarcomas as a JOA Committee on Musculoskeletal Tumors cooperative study. A total of 125 consecutive patients with high-grade bone (n = 77) and soft tissue (n = 48) sarcomas treated with neoadjuvant chemotherapy and definitive surgery in 25 tertiary referral hospitals were selected for the study. We investigated the correlation between the tumor size-based radiographic response evaluation criteria of preoperative chemotherapy for bone and soft tissue sarcomas provided by the JOA Committee on Musculoskeletal Tumors (hereafter called the JOA criteria) and the patients' overall survival using the Kaplan-Meier method and the log-rank test. RESULTS: The JOA criteria correlated relatively well with survival for malignant bone tumors (mostly comprising osteosarcoma and Ewing's sarcoma) but not for soft tissue sarcomas, suggesting that the tumor size-based radiographic evaluation criteria for the response to preoperative chemotherapy in patients with soft tissue sarcomas is invalid. CONCLUSIONS: The JOA criteria, based on the change in primary tumor size, is valid for malignant bone tumors but invalid for soft tissue sarcomas. Other new evaluation modalities of the response to preoperative chemotherapy using innovative functional imaging techniques are needed for soft tissue sarcomas.     

Infiltration of sarcomas into the hip joint: comparison of CT,MRI and histologic findings in 67 cases

We analyzed the incidence, route, and characteristics of hip joint infiltration in pelvic or proximal femoral sarcomas. 67 patients with a sarcoma that originated around the hip joint (50 pelvic and 17 femoral) were included in this study. Preoperative CT and MRI were matched with the histological findings in tumor specimens. Tumor infiltration into the hip joint was suspected on the basis of preoperative imaging in 29 patients due to articular cartilage disruption, diffuse signal changes in the acetabulum or femoral neck, signs of a tumor in the joint, or markedjoint effusion. Of these 29 patients, 15 showed tumor invasion on histological examination. 12 of 31 chondrosarcomas, none of 12 Ewing's sarcomas, and 3 of 24 osteosarcomas infiltrated into the hip joint (p = 0.008). 10 of 26 low-grade sarcomas and 5 of 41 high-grade sarcomas infiltrated into the hip joint (p = 0.02). The joint infiltration rate of the chondrosarcomas was related to their size. Of 10 tumors originating in the acetabulum, 9 penetrated through or around the osseous-ligamentous junction and one through the acetabular cartilage. In 5 proximal femur lesions, all infiltrated the joint through the femoral neck, 3 of them also through the ligamentum teres.     

Chromosomal changes in soft-tissue sarcomas. A new diagnostic parameter

A cytogenetic study was performed on short-term cultures from fresh surgical specimens obtained from 41 patients with soft-tissue sarcomas of various histologic origins. The results demonstrated that myxoid liposarcomas (five tumors) were associated with a specific translocation between chromosomes 12 and 16 and that synovial sarcomas (six tumors) were associated with a specific translocation between the X chromosome and chromosome 18. These chromosomal data have been used to differentiate myxoid liposarcoma from other myxoid tumors exhibiting a non-characteristic histologic picture, as well as to ascertain the diagnosis of synovial sarcoma in undifferentiated soft-tissue sarcomas. The results to date indicate that identification of specific chromosomal changes in sarcomas may provide a new diagnostic criterion for these tumors and possibly improve prognostication with regard to survival and response to treatment.     

Association of nm23-H1 with orthopedic oncological conditions

OBJECTIVE: To explore the correlation between nm23-H1 gene and malignant and semi-malignant bone tumors. METHOD: Thirty surgical specimens were collected, including 8 osteosarcomas, 7 giant cell tumors, 4 chondrosarcomas, 2 Ewing's sarcomas, 2 malignant fibrohistocytomas, 1 neurofibrosarcoma, 1 schwannoma, and 5 metastatic cancers. The expression of nm23-H1 in these specimens was observed by in situ hybridization and immunohistochemical staining. RESULT: The expression of nm23-H1 in 4 cases of primary giant cell tumor (GCT) was high, but was low or absent in 3 recurrent ones. In 4 cases of chondrosarcomas, the expression was positive. Its expression was basically negative in Ewing's tumor, malignant fibrous histiocytoma and metastatic sarcomas. CONCLUSION: There is no association of nm23-H1 with osteosarcoma.     

PRE-OPERATIVE CORE BIOPSY OF SOFT-TISSUE TUMOURS FACILITATES THEIR SURGICAL MANAGEMENT

Background: Soft-tissue sarcomas are rare, and clinical differentiation of benign tumours from sarcomas is sometimes impossible. Further, the diagnosis of soft-tissue sarcomas may be unsuspected pre-operatively, and the presenting mass enucleated. While enucleation (excisional biopsy) is acceptable for benign lesions, it is inappropriate for sarcomas, because the opportunity for the most effective management resulting in both adequate local control and functional limb salvage surgery is compromised. A high rate of wound complications following open incisional biopsy may also compromise local treatment. Inappropriate siting of the incision for both incisional and excisional biopsies may adversely affect subsequent surgery and radiotherapy. Methods: We therefore assessed the accuracy of core biopsy in the diagnosis of soft-tissue tumours, and planning of definitive surgery. All patients with primary soft-tissue tumours managed by two surgeons with a special interest in soft-tissue sarcomas since 1991 were reviewed. More than half (53%) were referred from other specialists. Results: Of 45 cases, 37 (82%) were referred with the tumour intact, and of these 31 (84%) underwent core biopsy. The overall accuracy of core biopsy was 84%. The sensitivity was 94%, with 100% specificity. In most patients this allowed planning of definitive one-stage surgery (P < 0.005). Of the remaining five non-diagnostic cores, four were benign and one was a non-specific malignancy. Conclusions: Core biopsy has a high degree of accuracy in the diagnosis of soft-tissue tumours, particularly malignant lesions, and is not misleading. Core biopsy avoids the complications of open biopsy, and enables planning of one-stage surgery when used in combination with appropriate imaging.     

MRI and CT in the preoperative evaluation of soft-tissue tumors

Summary The value of MRI and CT in the diagnosis of soft-tissue tumors was investigated in a prospective study of 25 patients. MRI and CT give a true reflection of the tumor dimensions. It is impossible, however, to make a reliable diagnosis with either technique. If both techniques are available, then MRI is to be preferred in view of the better spatial orientation and sharper contrast it offers between the tumor and adjacent structures. If only CT is available, then an adequate image can generally be obtained with this technique too.