No abstract available.
Drug Therapy* ; Osteosarcoma*

No abstract available.
Drug Therapy* ; Extremities* ; Osteosarcoma*

No abstract available.
Drug Therapy* ; Humans ; Osteosarcoma* ; Recurrence* ; Survival Rate*

Major progress in the management of osteosarcoma has been made due to advances in diagnostic imaging, operative technique, and chemotherapy, resulting in an improved survival. However, 20~30% of patients with osteosarcoma still develop distant metastases despite combined modality treatment. Currently various experimental efforts are being proposed to the future new strategy include drug resistance, suppression of metastasis mechanism, and targeted therapy to convert the incurable rate of 20~30% upto complete cure rate.
Diagnostic Imaging ; Drug Resistance ; Drug Therapy ; Humans ; Neoplasm Metastasis ; Osteosarcoma*

PURPOSE: The purpose of this study is to investigate the feasibility of bone cement as a vehicle of methotrexate, and potent chemotherapeutical drugs for osteosarcoma, and to evaluate the cytotoxic effect of the eluted methotrexate on osteosarcoma cells. MATERIALS AND METHODS: Various amounts of methotrexate were mixed with bone cement to make pellets containing corresponding dosages of methotrexate. The elution experiment was performed. The amount and the rate of elution, the duration of elution, and the elution pattern were checked daily by measuring the absorbance for four weeks. The cytotoxic effect of the eluted methotrexate on SaOS2 and MG63 osteosarcoma cells was examined by MTT assay, and the results were analyzed according to the concentration of the methotrexate and time. RESULTS: The amount of eluted methotrexate was the greatest during the first day, then the amount decreased rapidly until the end of the first week, reaching its plateau in the third week. The amount of eluted methotrexate from the pellets averaged 6.1% during the first week, and 9.6% during the four weeks. The concentration of eluted methotrexate was 130 to 10,000 times higher than the minimum inhibitory concentration throughout the experimental period. As a result of the cytotoxic effect of the eluted methotrexate, the number of viable tumor cells decreased significantly after 72 hours of exposure, and the viable cells were hardly seen after one week. CONCLUSIONS: In conclusion, the methotrexate eluted from the bone cement has sufficient cytotoxic effect on osteosarcoma cells in vitro, and the results suggest that local chemotherapy using a methotrexate loaded cement may be applicable in the management of osteosarcoma after evaluation of its long-term effect.
Cell Line* ; Drug Therapy ; Methotrexate* ; Microbial Sensitivity Tests ; Osteosarcoma*

PURPOSE: The current study was designed to evaluate the ability of thallium-201 scintigraphy to predict the response to preoperative chemotherapy in osteosarcoma, by comparing changes in thallium uptake ratio after chemotherapy to the tumor necrosis ratio. MATERIALS AND METHODS: Twelve osteosarcoma patients were included in this study. Thallium-201 scintigraphy was performed before and after preoperative chemotherapy, and the degree of tumor necrosis was estimated by histologic mapping postoperatively. To quantitatively determine thallium uptake, we drew a region of interest on the tumor side and on the contralateral normal side as a mirror image, and calculated the uptake ratio with dividing the gamma count in the tumor side by that of the normal side. We calculated these percent changes of thallium uptake ratio in the early and delayed phases, and compared these to the corresponding tumor necrosis ratio. RESULTS: Percent changes in the thallium uptake ratio were found to be correlated with the tumor necrosis ratio (p<0.03). This correlation was found in both the early (p<0.03) and delayed phase (p<0.03); moreover the correlation coefficient in early phase (0.79) was greater than that in the delayed phase (0.67). CONCLUSION: Thallium-201 scintigraphy could be effective at predicting the response to preoperative chemotherapy in osteosarcoma.
Drug Therapy* ; Humans ; Necrosis ; Osteosarcoma* ; Radionuclide Imaging* ; Thallium

Chemical investigation of the culture extract of an endophytic Penicillium citrinum from Dendrobium officinale, afforded nine citrinin derivatives (1-9) and one peptide-polyketide hybrid GKK1032B (10). The structures of these compounds were determined by spectroscopic methods. The absolute configurations of 1 and 2 were determined for the first time by calculation of electronic circular dichroism (ECD) data. Among them, GKK1032B (10) showed significant cytotoxicity against human osteosarcoma cell line MG63 with an IC₅₀ value of 3.49 μmol·L^-1, and a primary mechanistic study revealed that it induced the apoptosis of MG63 cellsvia caspase pathway activation.
Apoptosis ; Bone Neoplasms ; Caspases ; Humans ; Osteosarcoma/drug therapy* ; Penicillium

Maxillary osteosarcoma is an aggressive disease with a high mortality rate. Extensive surgical resection is accepted as the standard treatment for the disease. The beneficial role of chemotherapy and radiotherapy in the treatment of the disorders is uncertain. We experienced a case of an osteosarcoma of the maxillary sinus. Paranasal sinus computed tomography showed a huge solid mass lesion at the left maxillary sinus walls. An endoscopic biopsy showed an osteoblastic type osteosarcoma. In this case, radical surgery was impossible, and the patient was treated with chemotherapy and radiotherapy. This regimen involved four cycles of chemotherapy, cisplatin, 100 mg/m2 intravenously on the first day of weeks 1, 4, 7, and 10, and doxorubicin, 25 mg/m2 per day on the first 3 days of weeks 1, 4. 7. and 10, followed by external beam radiotherapy with a total dose of 6,600 cGy. We report here a case of an inoperable osteosarcoma of the maxilla with long-term survival after chemotherapy and radiotherapy with an accompanying review of the literature.
Biopsy ; Cisplatin ; Combined Modality Therapy ; Doxorubicin ; Drug Therapy* ; Humans ; Maxilla ; Maxillary Sinus* ; Mortality ; Osteoblasts ; Osteosarcoma* ; Radiotherapy*

Osteosarcoma is the most frequent primary bone tumor. Advances in combination chemotherapy and surgical technique have greatly improved the survival of patients with osteosarcoma. In Korea, improvements in osteosarcoma treatment have been made over the past two decades. The 5-year event-free survival rate of Korean children and adolescents with localized disease is 64.6%, comparable to that of American or European patients. This article provides an overview of current therapies for osteosarcoma in Korea.
Adolescent* ; Child* ; Disease-Free Survival ; Drug Therapy, Combination ; Humans ; Korea ; Osteosarcoma*

PURPOSE: To determine whether T1 mapping shows regional differences between viable and necrotic regions of osteosarcomas after anticancer chemotherapy and to assess whether this mapping is able to express the characteristics of various intramural tissue components. MATERIALS AND METHODS: Eleven of 20 osteosarcomas were included in this study, while the remaining nine were excluded because the tumor site was inappropriate for comparison of T1 map and tumor macrosection. All patients underwent MR imaging for the purpose of T1 mapping, followed by pre-operative chemotherapy and subsequentl limb-salvage surgery. Spin echo pulse sequencing was used with varying TR (100, 200, 400, 800, 1600, and 2400 msec) and a constant TE of 20 msec. Using a C-language software program, T1 relaxation time was calculated on a pixel-by-pixel basis and then a T1 map was generated by using a post-processing program, NIH Image. We attempted correlation of the T1 map and histologic findings, particularly in regions of interest(ROI) if certain areas were different from other regions on either the T1 or histologic map. Value was expressed as an average of the ratio of T1 of ROI and T1 of fat tissue, and this was used as an internal reference for normalization of the measurement. RESULTS: Tumor necrosis was 100%(Grade IV) in six specimens, and over 90 % (Grade III) in five. Viable tumor cells were found mostly in regions with chondroid matrix and seldom in regions with osteoid matrix. Regardless of cell viability, values ranged from 0.9 to 9.87(mean, 4.02) in tumor necrotic area with osteoid matrices, and from 3.04 to 3.9(mean, 3.55) in areas with chondroid matrices. Other regions with fibrous tissue proliferation, hemorrhage, and fatty necrosis showed values of 2.92-9.83(mean, 7.20), 2.65 -5.96(mean, 3.59), and 1.43 -3.11(mean, 2.68) respectively. The values of various tissues overlapped. No statistically significant difference was found between regions in which tumors were viable and those with tumor necrosis. CONCLUSION: Although we hypothesized that areas of necrotic tumor would show an increased water component(proton number) and would have a longer T1 value than viable tumor tissues, our results were otherwise. Necrotic osteosarcoma tissves showed a wide range of T1 values according to the prevailing tissue components.
Cell Survival ; Drug Therapy ; Hemorrhage ; Humans ; Magnetic Resonance Imaging ; Necrosis ; Osteosarcoma* ; Relaxation ; Theophylline