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Background: Postoperative deep infection after bone tumor surgery remains a serious complication. Although there are numerous reports about risk factors for postoperative deep infection in general surgery, there is only a small number of reports about those for bone tumor surgery. This retrospective study aimed to identify risk factors for postoperative deep infection after bone tumor resection. Methods: We reviewed data of 681 patients (844 bone tumors) who underwent surgery. Associations between variables, including age, recurrent tumor, pathological fracture, surgical site (pelvis/other), chemotherapy, biological reconstruction, augmentation of artificial bone or bone cement, the use of an implant, intraoperative blood loss, operative time, additional surgery for complications, and postoperative deep infection were evaluated. Results: The rate of postoperative deep infection was 3.2% (27/844 tumors). A pelvic tumor (odds ratio [OR]: 3.4, 95% confidence interval [CI]: 1.0–11.3) and use of an implant (OR: 9.3, 95% CI: 1.9–45.5) were associated with an increased risk of deep infection. Conclusions: This retrospective study showed that pelvic tumor and use of an implant were independent risk factors for deep infection. This information will help surgeons prepare an adequate surgical plan for patients with bone tumors. [ABSTRACT FROM AUTHOR]

The bone is a metabolically active organ which undergoes repeated remodeling cycles of bone resorption and formation. In this study, we revealed a robust and extremely long-lasting circadian rhythm in ex vivo culture maintained for over six months from the femoral bone of a PERIOD2Luciferase mouse. Furthermore, we also identified robust circadian clocks in flat bones. High- or low-magnification real-time bioluminescence microscopic imaging revealed that the robust circadian rhythms emanated from the articular cartilage and the epiphyseal cartilage within the growth plate of juvenile animals. Stimulation by forskolin or dexamethasone treatment caused type 0 phase resetting, indicating canonical entraining properties of the bone clock. Together, our findings from long-term ex vivo culture revealed that “tissue-autonomous” circadian rhythm in the articular cartilage and the growth plate of femoral bone functions for several months even in an organ culture condition, and provided a useful in vitro assay system investigating the role of the biological clock in bone formation or development. [ABSTRACT FROM AUTHOR]

Background: A variety of surgical procedures are now available for tissue reconstruction after osteosarcoma excision, and an important prognostic factor is the evaluation of response to chemotherapy using histology. Although tumor-bearing autografts are useful tools for reconstruction, re-use of the primary tumor may make it difficult to assess the histological response to chemotherapy, since the entire tumor cannot be analyzed. Here, we analyzed the prognostic value of the histological response in the patients who received frozen tumor-bearing autografts for reconstruction. Method: Retrospective analysis of the medical records of 51 patients with high-grade osteosarcoma of the extremities was performed. All patients received reconstruction using frozen tumor-bearing autografts. Tumor necrosis was evaluated in extraskeletal masses and cancellous bone. Results: Five-year overall survival of patients with good and poor response to chemotherapy was 82.9% and 46.4%, respectively (P = 0.044), and 5-year event-free survival was 57.7% and 36.0%, respectively (P = 0.329). Multivariate analysis revealed that a poor histological response to chemotherapy was a significant prognostic factor for overall survival (P = 0.033). Conclusion: Histological response is an important and reliable prognostic factor in patients undergoing reconstruction using frozen tumor-bearing autografts. [ABSTRACT FROM AUTHOR]

Background: Chemotherapy is essential to improve the prognosis of the patients with osteosarcoma, and the response to chemotherapy is an important prognostic factor. In this study, the impact of various radiological examinations on overall survival (OS) and event-free survival (EFS) was evaluated. Method: Eighty-two patients with high-grade osteosarcoma were included in this study, and we evaluated the following factors for prognostic significance: age (≥40 years), gender (male), tumor location (truncal site), metastatic disease, histological response to chemotherapy, radiological response to chemotherapy assessed using X-ray, angiography, CT, MRI, 201Tl scintigraphy, and 99mTc-MIBI scintigraphy (99mTc-MIBI), and combined radiological score (CRS). Results: Univariate analyses revealed that metastatic disease, histological response, 99mTc-MIBI, and CRS were significantly correlated with OS. Multivariate analyses showed that metastatic disease (OS: HR 35.9, P<0.001; EFS: HR 17.32, P<0.001) was an independent predictor of OS and EFS. Tumor location (HR 36.1, P = 0.003), histological response (HR 31.1, P = 0.036), and 99mTc-MIBI (HR 18.4, P = 0.038) were significant prognostic factors for OS. Moreover, CRS was a marginally significant predictor of OS and EFS. Conclusion: The chemotherapeutic effects evaluated by 99mTc-MIBI and CRS could be considered as prognostic factors in osteosarcoma. [ABSTRACT FROM AUTHOR]

Background: Dendritic cells (DCs) play a pivotal role in the immune system. There are many reports concerning DC-based immunotherapy. The differentiation and maturation of DCs is a critical part of DC-based immunotherapy. We investigated the differentiation and maturation of DCs in response to various stimuli. Methods: Thirty-one patients with malignant bone and soft tissue tumors were enrolled in this study. All the patients had metastatic tumors and/or recurrent tumors. Peripheral blood mononuclear cells (PBMCs) were suspended in media containing interleukin-4 (IL-4) and granulocyte-macrophage colony stimulating factor (GM-CSF). These cells were then treated with or without 1) tumor lysate (TL), 2) TL + TNF-α, 3) OK-432. The generated DCs were mixed and injected in the inguinal or axillary region. Treatment courses were performed every week and repeated 6 times. A portion of the cells were analyzed by flow cytometry to determine the degree of differentiation and maturation of the DCs. Serum IFN-c and serum IL-12 were measured in order to determine the immune response following the DC-based immunotherapy. Results: Approximately 50% of PBMCs differentiated into DCs. Maturation of the lysate-pulsed DCs was slightly increased. Maturation of the TL/TNF-α-pulsed DCs was increased, commensurate with OK-432-pulsed DCs. Serum IFN-γ and serum IL- 12 showed significant elevation at one and three months after DC-based immunotherapy. Conclusions: Although TL-pulsed DCs exhibit tumor specific immunity, TL-pulsed cells showed low levels of maturation. Conversely, the TL/TNF-α-pulsed DCs showed remarkable maturation. The combination of IL-4/GM-CSF/TL/TNF-α resulted in the greatest differentiation and maturation for DC-based immunotherapy for patients with bone and soft tissue tumors. [ABSTRACT FROM AUTHOR]

The bone is a metabolically active organ which undergoes repeated remodeling cycles of bone resorption and formation. In this study, we revealed a robust and extremely long-lasting circadian rhythm in ex vivo culture maintained for over six months from the femoral bone of a PERIOD2(Luciferase) mouse. Furthermore, we also identified robust circadian clocks in flat bones. High- or low-magnification real-time bioluminescence microscopic imaging revealed that the robust circadian rhythms emanated from the articular cartilage and the epiphyseal cartilage within the growth plate of juvenile animals. Stimulation by forskolin or dexamethasone treatment caused type 0 phase resetting, indicating canonical entraining properties of the bone clock. Together, our findings from long-term ex vivo culture revealed that "tissue-autonomous" circadian rhythm in the articular cartilage and the growth plate of femoral bone functions for several months even in an organ culture condition, and provided a useful in vitro assay system investigating the role of the biological clock in bone formation or development.