Chang-Bae Kong

RANKL expression is related to treatment outcome of patients with localized, high-grade osteosarcoma.

The receptor activator of nuclear factor κB ligand (RANKL/TNFSF11) is expressed in metastatic bone cancer cells and has been suggested to play a key role in cell migration and metastatic behavior. We determined whether RANKL expression is correlated to clinical behavior of localized, high‐grade osteosarcoma.

Combination of 18F-FDG PET/CT and Diffusion-Weighted MR Imaging as a Predictor of Histologic Response to Neoadjuvant Chemotherapy: Preliminary Results in Osteosarcoma

We evaluated the potential of 18F-FDG PET/CT and diffusion-weighted imaging (DWI) to monitor the histologic response in patients with extremity osteosarcoma receiving neoadjuvant chemotherapy, using sequential PET/CT and MR imaging. Methods: We prospectively registered 28 patients with high-grade osteosarcoma treated with 2 cycles of neoadjuvant chemotherapy and surgery. All patients underwent sequential 18F-FDG PET/CT and MR imaging before (PET/MR1) and after neoadjuvant chemotherapy (PET/MR2). Maximum standardized uptake value (SUV), tumor volume based on MR imaging (MRV), and the mean apparent diffusion coefficient (ADC) values were measured on PET/MR1 (SUV1, MRV1, and ADC1) and PET/MR2 (SUV2, MRV2, and ADC2). The percentage changes in maximum SUV (ΔSUV), MRV (ΔMRV), and ADC (ΔADC) were calculated, and the correlations among these parameters were evaluated. After surgery, the effects of neoadjuvant chemotherapy were graded histopathologically: grades III and IV (necrosis of ≥ 90%) indicated a good response, and grades I and II (necrosis of < 90%) indicated a poor response. The optimum cutoff values of ΔSUV, ΔMRV, ΔADC, and their combination for predicting histologic response were assessed by single- and multi-receiver-operating-characteristic curve analysis. Results: Twenty-seven patients were enrolled in the present study after 1 patient with inadequate acquisition of MR imaging was excluded. ΔSUV and ΔADC negatively correlated with each other (ρ = −0.593, P = 0.001), and ΔMRV did not correlate with ΔSUV or ΔADC. The cutoff value, sensitivity, specificity, and accuracy for predicting good histologic response were ≤ −52%, 67%, 87%, and 78%, respectively, for ΔSUV and > 13%, 83%, 73%, and 78%, respectively, for ΔADC. However, ΔMRV did not predict histologic response. Sensitivity, specificity, and accuracy were 83%, 87%, and 85%, respectively, using the combined criterion of ΔSUV ≤ −31% and ΔADC > 13%. Conclusion: In the current preliminary study, both PET/CT and DWI are useful for predicting histologic response after neoadjuvant chemotherapy in osteosarcoma. Combining PET/CT and DWI may be an effective method to predict the histologic response of patients to neoadjuvant chemotherapy.

Initial Metabolic Tumor Volume Measured by 18F-FDG PET/CT Can Predict the Outcome of Osteosarcoma of the Extremities

We evaluated the ability of metabolic and volumetric parameters measured by pretreatment 18F-FDG PET/CT to predict the survival of patients with osteosarcoma of the extremities. Methods: The records of 83 patients with American Joint Committee on Cancer stage II extremity osteosarcoma treated with surgery and chemotherapy were retrospectively reviewed. Imaging parameters (maximum standardized uptake value, metabolic tumor volume [MTV], total lesion glycolysis, and tumor volume based on MR images) were measured before treatment, and histologic responses to neoadjuvant chemotherapy were assessed by examination of postsurgical specimens. Receiver-operating-characteristic curve analyses and the Cox proportional hazards model were used to analyze whether imaging and clinicopathologic parameters could predict metastasis-free survival. Results: Of the imaging parameters, MTV at the fixed standardized uptake value threshold of 2.0 (MTV(2.0)) most accurately predicted metastasis by receiver-operating-characteristic curve analysis (area under the curve = 0.679, P = 0.011). By multivariate analysis, MTV(2.0) > 105 mL (relative risk, 3.93; 95% confidence interval, 1.55–9.92) and poor response to neoadjuvant chemotherapy (relative risk, 4.83; 95% confidence interval, 1.64–14.21) independently shortened metastasis-free survival (P = 0.004 for both parameters). The stratification of patients by the combined criteria of MTV(2.0) and histologic response predicted outcome in more detail. Conclusion: MTV is an independent predictor of metastasis in patients with osteosarcoma of the extremities. The combination of MTV and histologic response predicts survival more accurately than the chemotherapeutic response alone.

Treatment Outcome of Korean Patients with Localized Ewing Sarcoma Family of Tumors: A Single Institution Experience

OBJECTIVE Controversy exists about the treatment outcomes of the Ewing sarcoma family of tumors among low-incidence populations. We evaluated whether Korean Ewing sarcoma family of tumors patients have poorer outcomes than Euro-American patients. METHODS We retrospectively analyzed the clinicopathologic characteristics and outcomes of patients with localized Ewing sarcoma family of tumors treated at Korea Cancer Center Hospital between 1986 and 2008. RESULTS Seventy-six patients (48 male, 28 female) of median age 20 years (range: 1-69 years) were evaluated. Tumors were located in central-axial parts of the body in 33 cases (43.4%) and extremity in 43 cases (56.6%). Pelvis and femur were the most frequently involved sites. Histologic response to preoperative chemotherapy was analyzed in 48 cases and there were 32 (66.7%) good responders and 16 (33.3%) poor responders. For a median follow-up of 37.9 months (range: 0.9-260.6 months), 5-year overall survival and event-free survival rates were 58.9 ± 6.1 and 52.6 ± 6.1%, respectively. A poor histologic response to preoperative chemotherapy (P= 0.01) and a tumor location in a central-axial body region (P= 0.008) were found to be related to a poorer event-free survival. CONCLUSIONS Survival of our Ewing sarcoma family of tumors patients was not inferior to those reported for Euro-American cases. Collaborative studies are necessary for further improvements of outcome and we believe that our data provide a basis for future studies targeting Ewing sarcoma family of tumors.

Prognostic Value of SUVmax Measured by Pretreatment Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in Patients with Ewing Sarcoma.

Aim The aim of this retrospective study was to determine whether glucose metabolism assessed by using Fluorine-18 (F-18) fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) provides prognostic information independent of established prognostic factors in patients with Ewing sarcoma. Methods We retrospectively reviewed the medical records of 34 patients (men, 19; women, 15; mean age, 14.5 ± 9.7 years) with pathologically proven Ewing sarcoma. They had undergone F-18 FDG PET/CT as part of a pretreatment workup between September 2006 and April 2012. In this analysis, patients were classified by age, sex, initial location, size, and maximum standardized uptake value (SUVmax). The relationship between FDG uptake and survival was analyzed using the Kaplan-Meier method with the log-rank test and Cox’s proportional hazards regression model. Results The median survival time for all 34 subjects was 999 days and the median SUV by using PET/CT was 5.8 (range, 2–18.1). Patients with a SUVmax ≤ 5.8 survived significantly longer than those with a SUVmax > 5.8 (median survival time, 1265 vs. 656 days; p = 0.002). Survival was also found to be significantly related to age (p = 0.024), size (p = 0.03), and initial tumor location (p = 0.036). Multivariate analysis revealed that a higher SUVmax (p = 0.003; confidence interval [CI], 3.63–508.26; hazard ratio [HR], 42.98), older age (p = 0.023; CI, 1.34–54.80; HR, 8.59), and higher stage (p = 0.03; CI, 1.21–43.95; HR, 7.3) were associated with worse overall survival. Conclusions SUVmax measured by pretreatment F-18-FDG PET/CT can predict overall survival in patients with Ewing sarcoma.

Role of Surgical Margin on Local Recurrence in High Risk Extremity Osteosarcoma: A Case-Controlled Study

Background The relationship between surgical margin and local recurrence (LR) in osteosarcoma patients with poor responses to chemotherapy is unclear. Moreover, the incidences of LR according to three different resection planes (bone, soft tissue, and perineurovascular) are not commonly known. Methods We evaluated the incidence of LR in three areas. To assess whether there is a role of surgical margin on LR in patients resistant to preoperative chemotherapy, we designed a case (35 patients with LR) and control (70 patients without LR) study. Controls were matched for age, location, initial tumor volume, and tumor volume change during preoperative chemotherapy. Results LR occurred at the soft tissues in 18 cases (51.4%), at the perineurovascular tissues in 11 cases (31.4%), and at the bones in six cases (17.2%). The proportion of inadequate perineurovascular margin was higher in the case group than in the control group (p = 0.01). Within case-control group (105 patients), a correlation between each margin status and LR at corresponding area was found in the bone (p < 0.001) and perineurovascular area (p = 0.001). Conclusions LR is most common in soft tissues. In patients showing similar unfavorable responses to chemotherapy, the losses of perineurovascular fat plane on preoperative magnetic resonance imaging may be a valuable finding in predicting LR.

Outcome of re-excision for intralesionally treated parosteal osteosarcoma

The purpose of this study is to evaluate the risk of subsequent local recurrence (LR) and survival of parosteal osteosarcoma (POS) patients who underwent re‐excision after intralesional excision.

Soft-Tissue Ewing Sarcoma in a Low-incidence Population: Comparison to Skeletal Ewing Sarcoma for Clinical Characteristics and Treatment Outcome

OBJECTIVE Due to the low incidence, treatments for Korean soft tissue Ewing sarcoma patients have been heterogeneous, and reported data are limited. In this study, we retrospectively analyzed soft tissue Ewing cases treated at our institution. METHODS We analyzed the clinicopathologic characteristics and treatment outcome of soft tissue Ewing sarcoma patients and compared with those of skeletal cases. RESULTS Twenty-seven soft tissue Ewing sarcoma cases were evaluated. Patients with soft tissue Ewing sarcoma were older than patients with skeletal tumors (P = 0.03), and tended to have metastasis at diagnosis (P = 0.12). However, sex ratios, pathologies, tumor volumes, and histologic response to preoperative chemotherapy were not different in the two groups. The 5-year overall survival (49.0%) and event-free survival (45.6%) of soft tissue Ewing sarcoma patients were similar to those of skeletal tumor patients (51.8% and 46.0%, respectively). Presence of metastasis at diagnosis and poor histologic response to preoperative chemotherapy were associated with an adverse outcome for both groups. Similar to skeletal tumors, central tumor location, pathology and tumor volume tended to be related to the survival of soft tissue Ewing sarcoma. However, age and the use of a modality other than surgery to achieve local control did not influence the survival of soft tissue Ewing sarcoma patients. CONCLUSIONS Our data could provide a basis to design a collaborative or multinational study targeting Ewing sarcoma family tumors.

Zoledronic acid is an effective radiosensitizer in the treatment of osteosarcoma.

To overcome radioresistance in the treatment of osteosarcoma, a primary malignant tumor of the bone, radiotherapy is generally combined with radiosensitizers. The purpose of this study was to investigate a third-generation bisphosphonate, zoledronic acid (ZOL), as a radiosensitizer for osteosarcoma. We found that exposure of KHOS/NP osteosarcoma cells to 20 μM ZOL decreased the γ-radiation dose needed to kill 90% of cells. This radiosensitizing effect of ZOL was mediated through decreased mitochondrial membrane potential, increased levels of reactive oxygen species, increased DNA damage (as assessed by counting γ-H2AX foci), decreased abundance of proteins involved in DNA repair pathways (ATR, Rad52, and DNA-PKcs), and decreased phosphorylation of PI3K-Akt and MAPK pathway proteins (Raf1, MEK1/2, ERK1/2, and Akt), as compared to γ-irradiation alone. Cells treated with ZOL plus γ-irradiation showed impaired cell migration and invasion and reduced expression of epithelial-mesenchymal transition markers (vimentin, MMP9, and Slug). In Balb/c nude mice, the mean size of orthotopic osteosarcoma tumors 2 weeks post-inoculation was 195 mm3 following γ-irradiation (8 Gy), while it was 150 mm3 after γ-irradiation plus ZOL treatment (0.1 mg/kg twice weekly for 2 weeks). These results provide a rationale for combining ZOL with radiotherapy to treat osteosarcoma.

Pelvis and extremity osteosarcoma with similar tumor volume have an equivalent survival

The poor prognosis of pelvic osteosarcoma is well recognized, but the cause of this prognosis has not been well defined.