Background: This study aims to identify the incidence and risk factors of periprosthetic infections following endoprosthetic reconstruction of femoral metastatic bone disease (MBD). In this population with MBD, the marked impact of infection on the patient’s systemic treatment highlights the importance of understanding both the incidence and associated risk factors. Methods: This retrospective cohort study included a total of 140 patients who underwent endoprosthetic reconstruction for femoral MBD at a tertiary referral hospital in South Korea between 2009 and 2019. Infection-free survival was estimated using the Kaplan-Meier method, and Cox proportional hazards model analyses were performed to evaluate the risk factors associated with periprosthetic infection. Results: The incidence of periprosthetic infection in patients who underwent endoprosthetic reconstruction for femoral MBD was 9% (12 out of 140 patients). Risk factors for periprosthetic infection were hepatocellular carcinoma (HCC) as the primary tumor (hazard ratio [HR], 6.08; 95% CI, 1.63–22.6; p = 0.007) and low preoperative absolute neutrophil count (HR, 6.99; 95% CI, 1.79–27.4; p = 0.005). Conclusions Patients with femoral MBD had a 9% risk of developing a periprosthetic infection. Given their limited life expectancy, this translated to a substantial rate of 58.9 infections per 1,000 person-joint-years. Possible risk factors for periprosthetic infection were low preoperative absolute neutrophil count and HCC as the primary tumor. The high incidence of periprosthetic infection and its associated risk factors should be considered in patients undergoing endoprosthetic reconstruction for femoral MBD.

Background: This study aims to identify the incidence and risk factors of periprosthetic infections following endoprosthetic reconstruction of femoral metastatic bone disease (MBD). In this population with MBD, the marked impact of infection on the patient’s systemic treatment highlights the importance of understanding both the incidence and associated risk factors. Methods: This retrospective cohort study included a total of 140 patients who underwent endoprosthetic reconstruction for femoral MBD at a tertiary referral hospital in South Korea between 2009 and 2019. Infection-free survival was estimated using the Kaplan-Meier method, and Cox proportional hazards model analyses were performed to evaluate the risk factors associated with periprosthetic infection. Results: The incidence of periprosthetic infection in patients who underwent endoprosthetic reconstruction for femoral MBD was 9% (12 out of 140 patients). Risk factors for periprosthetic infection were hepatocellular carcinoma (HCC) as the primary tumor (hazard ratio [HR], 6.08; 95% CI, 1.63–22.6; p = 0.007) and low preoperative absolute neutrophil count (HR, 6.99; 95% CI, 1.79–27.4; p = 0.005). Conclusions Patients with femoral MBD had a 9% risk of developing a periprosthetic infection. Given their limited life expectancy, this translated to a substantial rate of 58.9 infections per 1,000 person-joint-years. Possible risk factors for periprosthetic infection were low preoperative absolute neutrophil count and HCC as the primary tumor. The high incidence of periprosthetic infection and its associated risk factors should be considered in patients undergoing endoprosthetic reconstruction for femoral MBD.

Background: This study aims to identify the incidence and risk factors of periprosthetic infections following endoprosthetic reconstruction of femoral metastatic bone disease (MBD). In this population with MBD, the marked impact of infection on the patient’s systemic treatment highlights the importance of understanding both the incidence and associated risk factors. Methods: This retrospective cohort study included a total of 140 patients who underwent endoprosthetic reconstruction for femoral MBD at a tertiary referral hospital in South Korea between 2009 and 2019. Infection-free survival was estimated using the Kaplan-Meier method, and Cox proportional hazards model analyses were performed to evaluate the risk factors associated with periprosthetic infection. Results: The incidence of periprosthetic infection in patients who underwent endoprosthetic reconstruction for femoral MBD was 9% (12 out of 140 patients). Risk factors for periprosthetic infection were hepatocellular carcinoma (HCC) as the primary tumor (hazard ratio [HR], 6.08; 95% CI, 1.63–22.6; p = 0.007) and low preoperative absolute neutrophil count (HR, 6.99; 95% CI, 1.79–27.4; p = 0.005). Conclusions Patients with femoral MBD had a 9% risk of developing a periprosthetic infection. Given their limited life expectancy, this translated to a substantial rate of 58.9 infections per 1,000 person-joint-years. Possible risk factors for periprosthetic infection were low preoperative absolute neutrophil count and HCC as the primary tumor. The high incidence of periprosthetic infection and its associated risk factors should be considered in patients undergoing endoprosthetic reconstruction for femoral MBD.

Background: This study aims to identify the incidence and risk factors of periprosthetic infections following endoprosthetic reconstruction of femoral metastatic bone disease (MBD). In this population with MBD, the marked impact of infection on the patient’s systemic treatment highlights the importance of understanding both the incidence and associated risk factors. Methods: This retrospective cohort study included a total of 140 patients who underwent endoprosthetic reconstruction for femoral MBD at a tertiary referral hospital in South Korea between 2009 and 2019. Infection-free survival was estimated using the Kaplan-Meier method, and Cox proportional hazards model analyses were performed to evaluate the risk factors associated with periprosthetic infection. Results: The incidence of periprosthetic infection in patients who underwent endoprosthetic reconstruction for femoral MBD was 9% (12 out of 140 patients). Risk factors for periprosthetic infection were hepatocellular carcinoma (HCC) as the primary tumor (hazard ratio [HR], 6.08; 95% CI, 1.63–22.6; p = 0.007) and low preoperative absolute neutrophil count (HR, 6.99; 95% CI, 1.79–27.4; p = 0.005). Conclusions Patients with femoral MBD had a 9% risk of developing a periprosthetic infection. Given their limited life expectancy, this translated to a substantial rate of 58.9 infections per 1,000 person-joint-years. Possible risk factors for periprosthetic infection were low preoperative absolute neutrophil count and HCC as the primary tumor. The high incidence of periprosthetic infection and its associated risk factors should be considered in patients undergoing endoprosthetic reconstruction for femoral MBD.

Purpose: Brain metastasis rarely occurs in soft tissue sarcoma (STS). Here, we present five cases of STS with brain metastases with genetic profiles. Materials and Methods: We included five patients from Seoul National University Hospital who were diagnosed with STS with metastasis to the brain. Tissue from the brain metastasis along with that from the primary site or other metastases were used for DNA and RNA sequencing to identify genetic profiles. Gene expression profiles were compared with sarcoma samples from The Cancer Genome Atlas. Results: The overall survival after diagnosis of brain metastasis ranged from 2.2 to 34.3 months. Comparison of mutational profiles between brain metastases and matched primary or other metastatic samples showed similar profiles. In two patients, copy number variation profiles between brain metastasis and other tumors showed several differences including MYCL, JUN, MYC, and DDR2 amplification. Gene ontology analysis showed that the group of genes significantly highly expressed in the brain metastasis samples was enriched in the G-protein coupled receptor activity, structural constituent of chromatin, protein heterodimerization activity, and binding of DNA, RNA, and protein. Gene set enrichment analysis showed enrichment in the pathway of neuroactive ligand-receptor interaction and systemic lupus erythematosus. Conclusion The five patients had variable ranges of clinical courses and outcomes. Genomic and transcriptomic analysis of STS with brain metastasis implicates possible involvement of complex expression modification and epigenetic changes rather than the addition of single driver gene alteration.

Purpose: Seoul National University College of Medicine operates a faculty development program for clinical teachers at multiple affiliated teaching hospitals. In 2020, the program was moved online due to coronavirus disease 2019. The purpose of this study was to determine whether it is feasible and effective to provide faculty development programs online in terms of clinical teachers’ participation and satisfaction in comparison with offline programs. Methods: Clinical teachers participated in the clinical teaching methods programs offline in 2019 and online in 2020. We analyzed participation rate and satisfaction level. All surveys items were rated on a 5-point Likert scale. We also interviewed instructors about the advantages and drawbacks of the online program. Results: The participation rate of the online program (89.5%) was significantly higher than that of the offline program (67.8%). The overall satisfaction level for the online program (4.37) was similar to that for the offline program (4.50). Conclusion Faculty development programs online are feasible and effective in medical education. We need to design training content that fits online programs, consider various online training methods to reinforce the strengths of online programs, and support participants to make good use of these programs.

Purpose: Seoul National University College of Medicine operates a faculty development program for clinical teachers at multiple affiliated teaching hospitals. In 2020, the program was moved online due to coronavirus disease 2019. The purpose of this study was to determine whether it is feasible and effective to provide faculty development programs online in terms of clinical teachers’ participation and satisfaction in comparison with offline programs. Methods: Clinical teachers participated in the clinical teaching methods programs offline in 2019 and online in 2020. We analyzed participation rate and satisfaction level. All surveys items were rated on a 5-point Likert scale. We also interviewed instructors about the advantages and drawbacks of the online program. Results: The participation rate of the online program (89.5%) was significantly higher than that of the offline program (67.8%). The overall satisfaction level for the online program (4.37) was similar to that for the offline program (4.50). Conclusion Faculty development programs online are feasible and effective in medical education. We need to design training content that fits online programs, consider various online training methods to reinforce the strengths of online programs, and support participants to make good use of these programs.

BACKGROUND: Spontaneous disease stabilization of desmoid-type fibromatosis (DF) has been demonstrated in many reports, and the watchful waiting approach without any frontline treatment is becoming popular as an initial management strategy. In this study, we aimed to assess the disease stabilization rate and identify predictive factors for disease stabilization of DF in patients with conservative treatment. METHODS: We reviewed 76 patients with sporadic extra-abdominal DF who were managed with frontline conservative treatment in our institute. The minimum follow-up was 12 months. Stabilization was defined as radiological evidence of no change or continuous decrease in size of the tumor for six months or more. The primary endpoint was stabilization of DF. Possible patient-, disease-, and treatment-related factors predictive of disease stabilization were analyzed with multivariate analysis. RESULTS: At final follow-up, 54 of the 76 tumors (71%) were stable, and mean time to stabilization was 30.4 months (range, 7 to 112 months). On Kaplan-Meier survival analysis, the spontaneous stabilization rate was 25.4% at one year, 52.7% at two years, and 70.9% at three years. The mean time to spontaneous stabilization was longer in patients with ≤ 40 years of age (p = 0.022) or recurrence (p = 0.041). On multivariate analysis with the Cox proportional hazard method, recurrence (hazard ratio [HR], 1.79; p = 0.041) and younger age (HR, 2.04; p = 0.022) were identified as independent prognostic factors for longer time to disease stabilization. CONCLUSIONS Frontline conservative treatment seems to be the optimal treatment for most patients with DF. Younger patients or those with recurrence may require longer time to spontaneous disease stabilization.

Background: Cancer stem cells (CSCs) are cells characterized by their self-renewal and tumorigenic potential. The purpose of this study was to discover the role of the delta-like factor 1 (DLK1) in sarcoma. Methods: mRNA expression of DLK1 from 13 sarcoma cell lines was examined. Isolated CSCs from the tumors were examined using fluorescence-activated cell sorting (FACS) with CD133, the CSC marker, or sphere-forming assay. The relationship between DLK1 and CSCs in sarcoma was examined using cell proliferation and cell invasion assays after they were treated with DLK1 short interfering RNA (siRNA). Results: A high expression of DLK1 mRNA was observed in all sarcoma cell lines. However, CSCs were isolated from over expressed sarcomas of the DLK1 gene, and they have shown to be expressed lower than the wild type. The anti-cancer effects of DLK1 siRNA inhibited cell proliferation and invasion in U2OS, A204, and sw872. In addition, treatment with DLK1 siRNA inhibited cell invasion in sw872 CSCs. DLK1 gene induces tumorigenesis in various sarcoma cells and regulates the invasiveness of liposarcoma. These results suggest that DLK1 could serve as a possible therapeutic target for sarcoma. Conclusions Our study showed that the DLK1 gene induces tumorigenesis in various sarcomas and is associated with invasive mechanism in sarcoma. These results suggest DLK1 could serve as a possible therapeutic target in a variety of sarcomas.

PURPOSE: To identify prognostic factors influencing progression-free survival (PFS) of aggressive fibromatosis (AF) after postoperative radiotherapy (PORT) and assess correlations between immunohistochemistry (IHC) features of β-catenin/smooth muscle actin (SMA) and PFS. MATERIALS AND METHODS: Records of 37 patients with AF treated by PORT from 1984 to 2015 were retrospectively reviewed. Fifteen patients underwent wide excision for AF and 22 patients received debulking operation. The median total dose of PORT was 59.4 Gy. IHC staining results of β-catenin and SMA were available for 11 and 12 patients, respectively. RESULTS: The median follow-up duration was 105.9 months. Five-year PFS rate was 70.9%. Tumor size or margin status was not related to PFS in univariate analysis (p = 0.197 and p = 0.716, respectively). Multivariate analysis showed that increased interval from surgery to PORT (>5.7 weeks) was a marginal risk factor for PFS (p = 0.054). Administration of PORT at the initial diagnosis resulted in significantly improved PFS compared to deferring PORT after recurrence (p = 0.045). Patient with both risk factors of deferring PORT after recurrence and interval from surgery to PORT >5.7 weeks had significantly lower 5-year PFS than patients without risk factor (34.1% vs. 100.0%; p = 0.012). Nuclear β-catenin intensity tended to inversely correlate with 5-year PFS, although it did not reach statistical significance (62.5% at low vs. 100.0% at high; p = 0.260). SMA intensity was not related to PFS (p = 0.700). CONCLUSION: PORT should be performed immediately after surgery irrespective of margin status or tumor size especially in recurrent case. Nuclear β-catenin staining intensity of IHC might correlate with local recurrence.
Actins ; beta Catenin ; Diagnosis ; Disease-Free Survival ; Fibromatosis, Aggressive ; Follow-Up Studies ; Humans ; Immunohistochemistry ; Multivariate Analysis ; Radiotherapy ; Radiotherapy, Adjuvant ; Recurrence ; Retrospective Studies ; Risk Factors