Dae Geun Jeon

Primary Osteosarcoma in Patients Older than 40 Years of Age

Among the 665 patients who registered at our hospital, we reviewed 39 cases of high grade primary osteosarcoma in patients who were older than 40 yr of age. The aim of this study was to determine if a primary osteosarcoma in older patients has different clinical features, and a poorer prognosis than in younger patients. Two evaluations were performed. In the first, an attempt was made to determine the possible prognostic factors such as gender, location, size, alkaline phosphatase, radiological findings, chemotherapy intensity, chemotherapy-induced tumor necrosis, and surgical margin. The second evaluation involved assessment of whether there were any significant clinical differences between older patients and adolescents. According to the results, a primary osteosarcoma in older patients did not reveal any significant prognostic variables. A primary osteosarcoma in older patients showed a poorer prognosis due to relatively unusual locations, common abnormal radiological findings, and a poor response to chemotherapy. Therefore, careful attention should be paid to making an accurate diagnosis and new strategies for more effective treatment, including chemotherapy, must to be developed in order to achieve long term survival in older patients with osteosarcoma.

Epidermal Growth Factor Receptor: Is It a Feasible Target for the Treatment of Osteosarcoma?

Purpose Features of epidermal growth factor receptor (EGFR) expression in osteosarcoma and in vitro efficacies of EGFR inhibitors against osteosarcoma cells were evaluated. Materials and Methods Thirty biopsy samples of osteosarcoma patients were retrospectively analyzed for EGFR protein expression by immunohistochemistry. Relationships between EGFR expression and clinicopathologic characteristics and treatment outcomes were evaluated. Four osteosarcoma cell lines were analyzed for EGFR and p-EGFR expression by western blotting. Efficacies of gefitinib and BIBW2992 on osteosarcoma cells were evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Tyrosine kinase domains in exons 18 to 21 were sequenced and gene expression analyses of EGFR and PTEN were performed in four osteosarcoma cell lines. Results EGFR protein was expressed in 27 (90%) samples (6 low, 12 intermediate, 9 high) and in three cell lines. Intermediate or high staining for EGFR was related to a tumor volume<150 mL (p<0.001) and histologic subtype other than osteoblastic type (p=0.03). However, EGFR expression was not associated with histologic response to preoperative chemotherapy or survival. Gefitinib and BIBW 2992 did not have any significant inhibitory effect on cell viabilities. DNA sequencing analysis revealed three osteosarcoma cell lines have single base changes at codon 2361 of exon 20 (G to A), without affecting translation results. Furthermore, no mutation was found to be associated with constitutive EGFR activation. Conclusion In the present study, gefitinib and BIBW2992 were not effective against osteosarcoma cells. However, as osteosarcoma cells express EGFR, further studies are necessary to explore the potential of other therapeutic agents targeting EGFR.

In Vitro Chemosensitivity Test of Human Soft Tissue Sarcoma Using the HDRA (Histoculture Drug Response Assay) Method

Purpose: To investigate the variation in the chemosensitivity in soft tissue sarcoma (STS), fresh biopsy with sample for culture was tested using the histoculture drug response assay (HDRA) method. Materials and Methods: 30 samples of fresh STS were obtained during either biopsy or surgical removal at our hospital between March, 2002 and March, 2004. Results: Drug sensitivity testing by HDRA showed that two drug, Doxorubicin and CDDP, had a significantly higher inhibition rate than BLM, CTX, DTIC, VCR or VP-16 in the thirty STS tested. Doxorubicin showed the highest inhibition rate in the liposarcoma. CDDP shoewd the significant inhibition rate in the synovial sarcoma and malignant fibrous histiocytpma. Depending on the morphological type, round cell sarcoma and pleomorphic sarcoma were more sensitive to Doxorubicin and CDDP than spindle cell sarcoma. In the round cell sarcoma, BLM, CTX, VP-16 and IFS also showed above 30% inhibition rate. Conclusion: Drug sensitivity testing in STS should be evaluated with clinical outcome in the future and then HDRA will provide useful information for selection of an anticancer agent for STS because of its ease of evaluation and high predictability.

Osteosarcoma Arising in a Multiple Osteochondromatosis: A Case Report

Osteochondroma, the most frequent benign bone tumor, is composed of trabecular bone covered with a hyaline cartilage cap. It is well known that multiple osteochondromatosis may undergo malignant change. Such sarcomatous change usually present with the form of chondrosarcoma, and transformation to other malignancy is extremely rare. This report describes one case of osteosarcoma arising in patients who had multiple osteochondromatosis, and includes brief review of the literatures.

Reconstruction of Knee Joint with Total Elbow Endoprosthesis in Eight Years Old Osteosarcoma of Distal Femur: A Case Report

Although the reconstruction with tumor prosthesis is a routine procedure for extremity sarcomas, this option has some technical limitation in children under 10 years old. Customized expandable tumor prosthesis is too expensive in most cases and arthrodesis of any kind is not functional. This report presents one case of osteosarcoma of distal femur in eight years old child which was reconstructed with adult type total elbow endoprosthesis as a reconstructive option, and includes brief review of the literature.