Purpose: Few studies have been conducted on the level of cortical atrophy and whether its incidence increases according to the surgical site. Therefore, this study compared the reduction ratio of cortical atrophy at each stem level and the incidence rates of cortical atrophy at the surgical sites. Materials and Methods: This study retrospectively reviewed 45 stems (17 on the tibia, three on the humerus, and 25 on the femur) from 29 patients who underwent a wide excision of malignant bone or soft tissue tumors with tumor prosthesis surgery, from January 2008 to January 2023. The cortical thickness was measured using plain radiographs in the anteroposterior and lateral views along each stem level, with intervals close to a year. Results: The mean patient age was 55.0 years (range, 21.0–79.0 years), and the mean follow-up period was 4.1 years (range, 1.3–12.5 years). Grade 1 cortical atrophy (20%–50% reduction) was observed in 19 stems (nine stems on the tibia, two stems on the humerus, and eight stems on the femur), of which 10 were non-cement, and nine were cement within an average of 2.24 years. Grade 2 cortical atrophy (>50% reduction) was observed in three of 19 stems, two of which eventually developed from grade 1 cortical atrophy within an average of 3.19 years. Fourteen stems showed cortical atrophy 1 cm below the resection level. In contrast, four, three, and two stems showed cortical atrophy at the midline level of the stem, the tip of the stem, and the end of the cement line, respectively. The reduction ratios of the bone length between the atrophic and non-atrophic groups were 43.3% and 43.6%, respectively, and no significant difference was observed between the groups. Conclusion Depending on the specific stem level, cortical atrophy can be observed more frequently in a specific period, but it is not observed more frequently according to the resection site, resection length, or use of cemented or non-cemented stems. Care should be taken to monitor cortical atrophy to prevent prosthetic failure, and the expansion of tumor prosthesis surgery should be achieved through a large multicenter prospective study to gain additional insights.

Purpose: Few studies have been conducted on the level of cortical atrophy and whether its incidence increases according to the surgical site. Therefore, this study compared the reduction ratio of cortical atrophy at each stem level and the incidence rates of cortical atrophy at the surgical sites. Materials and Methods: This study retrospectively reviewed 45 stems (17 on the tibia, three on the humerus, and 25 on the femur) from 29 patients who underwent a wide excision of malignant bone or soft tissue tumors with tumor prosthesis surgery, from January 2008 to January 2023. The cortical thickness was measured using plain radiographs in the anteroposterior and lateral views along each stem level, with intervals close to a year. Results: The mean patient age was 55.0 years (range, 21.0–79.0 years), and the mean follow-up period was 4.1 years (range, 1.3–12.5 years). Grade 1 cortical atrophy (20%–50% reduction) was observed in 19 stems (nine stems on the tibia, two stems on the humerus, and eight stems on the femur), of which 10 were non-cement, and nine were cement within an average of 2.24 years. Grade 2 cortical atrophy (>50% reduction) was observed in three of 19 stems, two of which eventually developed from grade 1 cortical atrophy within an average of 3.19 years. Fourteen stems showed cortical atrophy 1 cm below the resection level. In contrast, four, three, and two stems showed cortical atrophy at the midline level of the stem, the tip of the stem, and the end of the cement line, respectively. The reduction ratios of the bone length between the atrophic and non-atrophic groups were 43.3% and 43.6%, respectively, and no significant difference was observed between the groups. Conclusion Depending on the specific stem level, cortical atrophy can be observed more frequently in a specific period, but it is not observed more frequently according to the resection site, resection length, or use of cemented or non-cemented stems. Care should be taken to monitor cortical atrophy to prevent prosthetic failure, and the expansion of tumor prosthesis surgery should be achieved through a large multicenter prospective study to gain additional insights.

Purpose: Few studies have been conducted on the level of cortical atrophy and whether its incidence increases according to the surgical site. Therefore, this study compared the reduction ratio of cortical atrophy at each stem level and the incidence rates of cortical atrophy at the surgical sites. Materials and Methods: This study retrospectively reviewed 45 stems (17 on the tibia, three on the humerus, and 25 on the femur) from 29 patients who underwent a wide excision of malignant bone or soft tissue tumors with tumor prosthesis surgery, from January 2008 to January 2023. The cortical thickness was measured using plain radiographs in the anteroposterior and lateral views along each stem level, with intervals close to a year. Results: The mean patient age was 55.0 years (range, 21.0–79.0 years), and the mean follow-up period was 4.1 years (range, 1.3–12.5 years). Grade 1 cortical atrophy (20%–50% reduction) was observed in 19 stems (nine stems on the tibia, two stems on the humerus, and eight stems on the femur), of which 10 were non-cement, and nine were cement within an average of 2.24 years. Grade 2 cortical atrophy (>50% reduction) was observed in three of 19 stems, two of which eventually developed from grade 1 cortical atrophy within an average of 3.19 years. Fourteen stems showed cortical atrophy 1 cm below the resection level. In contrast, four, three, and two stems showed cortical atrophy at the midline level of the stem, the tip of the stem, and the end of the cement line, respectively. The reduction ratios of the bone length between the atrophic and non-atrophic groups were 43.3% and 43.6%, respectively, and no significant difference was observed between the groups. Conclusion Depending on the specific stem level, cortical atrophy can be observed more frequently in a specific period, but it is not observed more frequently according to the resection site, resection length, or use of cemented or non-cemented stems. Care should be taken to monitor cortical atrophy to prevent prosthetic failure, and the expansion of tumor prosthesis surgery should be achieved through a large multicenter prospective study to gain additional insights.

Background: During the coronavirus disease 2019 (COVID-19) pandemic, patients with myasthenia gravis (MG) were more susceptible to poor outcomes owing to respiratory muscle weakness and immunotherapy. Several studies conducted in the early stages of the COVID-19 pandemic reported higher mortality in patients with MG compared to the general population. This study aimed to investigate the clinical course and prognosis of COVID-19 in patients with MG and to compare these parameters between vaccinated and unvaccinated patients in South Korea. Methods: This multicenter, retrospective study, which was conducted at 14 tertiary hospitals in South Korea, reviewed the medical records and identified MG patients who contracted COVID-19 between February 2022 and April 2022. The demographic and clinical characteristics associated with MG and vaccination status were collected. The clinical outcomes of COVID-19 infection and MG were investigated and compared between the vaccinated and unvaccinated patients. Results: Ninety-two patients with MG contracted COVID-19 during the study. Nine (9.8%) patients required hospitalization, 4 (4.3%) of whom were admitted to the intensive care unit. Seventy-five of 92 patients were vaccinated before contracting COVID-19 infection, and 17 were not. During the COVID-19 infection, 6 of 17 (35.3%) unvaccinated patients were hospitalized, whereas 3 of 75 (4.0%) vaccinated patients were hospitalized (P < 0.001). The frequencies of ICU admission and mechanical ventilation were significantly lower in the vaccinated patients than in the unvaccinated patients (P = 0.019 and P = 0.032, respectively). The rate of MG deterioration was significantly lower in the vaccinated patients than in the unvaccinated patients (P = 0.041). Logistic regression after weighting revealed that the risk of hospitalization and MG deterioration after COVID-19 infection was significantly lower in the vaccinated patients than in the unvaccinated patients. Conclusion This study suggests that the clinical course and prognosis of patients with MG who contracted COVID-19 during the dominance of the omicron variant of COVID-19 may be milder than those at the early phase of the COVID-19 pandemic when vaccination was unavailable. Vaccination may reduce the morbidity of COVID-19 in patients with MG and effectively prevent MG deterioration induced by COVID-19 infection.

Purpose: Soft tissue sarcomas (STS) are a group of rare mesenchymal cancers with more than 50 histological subtypes. A recently published study identified the chemosensitivity according to the tumor subtype and grade. This study assessed the efficacy of gemcitabine/ docetaxel (GD) and other agents by comparing the results with the literature. Materials and Methods: One hundred and eight patients with STS were enrolled between May 2012 and February 2020. Sixteen cases (16 patients) received second-line pazopanib or GD for advanced STS. The progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier product-limit method. The overall response rate (ORR) was determined based on the proportion of individuals within a treatment group who achieved either a partial response or complete response to the treatment within a specific timeframe. The quality of life of the patients before and after chemotherapy was evaluated using the EORTC QLQ-C30 (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire) questionnaire. Results: Pazopanib yielded a median OS of 13.2 months and a median PFS of 10.8 months at the authors’ institution. The median OS and PFS for GD were 16.0 and 12.9 months, respectively. In the present 16 assessable cases, GD and pazopanib achieved a 37.5% ORR. After chemotherapy, the EORTC QLQ-C30 functional scale score improved in both groups, but the difference was not statistically significant. Conclusion Pazopanib and GD may be effective second-line treatments for improving the OS and PFS. GD was associated with a better OS and ORR than pazopanib in patients with advanced STS and appeared more efficient.

Purpose: Differential diagnosis between benign and malignant tumors is critical for appropriate treatment. Patients with soft tissue sarcomas of the foot and ankle are often diagnosed late, and it can be predicted their prognosis will be poor. This study was aimed to investigate whether the delayed diagnosis of soft tissue sarcoma of the foot and ankle affects the oncological results and prognoses. Materials and Methods: We retrospectively reviewed the data from our tumor database and included all patients who had undergone a first wide excision of primary soft tissue sarcoma of the foot and ankle. Wide excision had been performed at a single regional musculoskeletal oncology center, and the patients had been followed up for more than 1 year. Between January 2007 to January 2021, we reviewed 26 patients with soft tissue sarcomas of the foot and ankle. Statistical analyses were performed by dividing the time of diagnosis based on 6 months, 1 year, 2 years, and 5 years or more. The primary endpoints of the study were overall, local recurrence-free, and metastasis-free survival rates. Actuarial survival was estimated using the Kaplan–Meier method and Cox regression analysis. The log-rank test was used to determine whether there was a significant difference between the survival curves according to the time of diagnosis. Results: Six, eight, and ten patients died, had distant metastasis, and developed local recurrence during the study period, respectively. The 5-year overall survival, 5-year metastasis-free survival, and 5-year local recurrence-free survival rates of the entire patient group were 80.1%, 73.0%, and 56.7%, respectively. The 5-year overall survival rate was higher in patients diagnosed earlier when the duration until diagnosis was 1 and 5 years than in those diagnosed later. A statistically insignificant difference was observed in local recurrence and distant metastasis during each period according to the diagnostic delay. Conclusion Delayed diagnosis in patients with soft tissue sarcoma of the foot and ankle has no influence on the oncological prognosis. Therefore, even if the self-observation period is long in the above patients, it is necessary to actively engage in treatment.

Chondromyxoid fibroma is a rare bone tumor of cartilaginous origin, representing less than 1% of all bone tumors. It preferentially arises in the eccentric location of the metaphysis of a long tubular bone. Juxtacortical locations are reported infrequently in the long bones and even more rarely in short tubular bones, with only three cases documented. Here we present two new cases of juxtacortical chondromyxoid fibroma in the small bones. One was an intracortical osteolytic lesion of the metatarsal bone of the foot with degenerative atypia that histologically should be differentiated from chondrosarcoma. The other was a phalangeal mass protruding into the interphalangeal joint of the hand, which had been labeled mistakenly as a soft tissue mass preoperatively. These cases illustrated that chondromyxoid fibromas have various the manifestations and should be included in the differential diagnosis of an osteolytic lesion or an exophytic mass in the small bones.

Background: and Purpose Fingolimod (FTY) inhibits lymphocyte egress from lymphoid organs to cause lymphopenia, but the clinical implications of FTY-induced lymphopenia are not fully understood. We aimed to determine the frequency and severity of lymphopenia during FTY treatment among Korean patients with multiple sclerosis (MS), and its association with infections. Methods: We retrospectively reviewed the medical records of patients with MS treated using FTY from 12 referral centers in South Korea between March 2013 and June 2021. Patients were classified according to their nadir absolute lymphocyte count (ALC) during treatment:grade 1, 800–999/μL; grade 2, 500–799/μL; grade 3, 200–499/μL; and grade 4, <200/μL. Results: FTY treatment was administered to 69 patients with a median duration of 18 months (range=1–169 months), with 11 patients being treated for ≥7 years. During FTY treatment, mean ALCs were reduced after the first month (653.0±268.9/μL, mean±standard deviation) (p<0.0001) and remained low during treatment lasting up to 84 months. During follow-up, 41 (59.4%) and 7 (10.1%) patients developed grade-3 and grade-4 lymphopenia, respectively.No significant difference was found in age at FTY initiation, sex, baseline ALC, body mass index, or prior disease-modifying treatment between patients with and without grade-4 lymphopenia. Infections were observed in 11 (15.9%) patients, and the frequencies of patients with and without grade-4 lymphopenia were similar. Conclusions FTY treatment induced grade-4 lymphopenia in 10% of South Korean patients with MS, but did not appear to be associated with an increased infection risk.

Background: Bone tumors can cause severe pain and poor quality of life due to recurrence and non-achievement of complete remission after surgery, chemotherapy, or radiotherapy. Radiofrequency ablation (RFA) can be considered for minimally invasive treatment of bone tumors that are difficult to radically excise. In this study, RFA was performed for bone tumors that were difficult to radically excise and did not respond to surgery, chemotherapy, or radiotherapy due to their large sizes and/or locations. The purpose of this study was to retrospectively analyze the clinical characteristics and survival rates of bone tumors after RFA and provide one more treatment option for the future. Methods: There were 43 patients with bone tumors who underwent percutaneous RFA at our hospital from April 2007 to October 2017. The median age of the patients was 59 years (range, 31–75 years), and the median follow-up duration was 67.2 months (range, 10.2–130.5 months). Of the 43 patients, 26 were male and 17 were female. Thirty-four cases were metastatic bone tumors, 5 were chordomas, 3 were osteosarcomas, and 1 was a giant cell tumor. Pain and functional ability of the patients were evaluated using a visual analog scale (VAS) and the Musculoskeletal Tumor Society (MSTS) functional scoring system, respectively. Scores were recorded preoperatively, 1 week postoperatively, and 4 weeks postoperatively. The 1-year, 2-year, and 5-year survival rates were evaluated using the Kaplan-Meier method. Results: The mean VAS score was 8.21 preoperatively. The mean VAS score at 1 week, 4 weeks, 12 weeks, and 24 weeks postoperatively were 3.91, 3.67, 3.31, and 3.12, respectively. The mean preoperative MSTS score was 64.0% (range, 32%–87%). The mean postoperative MSTS score was 71.0% (range, 40%–90%). The 1-year, 2-year, and 5-year survival rates were 95.3%, 69.8%, and 30.2%, respectively. Conclusions As per our study findings, RFA was effective in reducing pain and improving functional ability of patients with bone tumors that were difficult to radically excise.

Background: Bone tumors can cause severe pain and poor quality of life due to recurrence and non-achievement of complete remission after surgery, chemotherapy, or radiotherapy. Radiofrequency ablation (RFA) can be considered for minimally invasive treatment of bone tumors that are difficult to radically excise. In this study, RFA was performed for bone tumors that were difficult to radically excise and did not respond to surgery, chemotherapy, or radiotherapy due to their large sizes and/or locations. The purpose of this study was to retrospectively analyze the clinical characteristics and survival rates of bone tumors after RFA and provide one more treatment option for the future. Methods: There were 43 patients with bone tumors who underwent percutaneous RFA at our hospital from April 2007 to October 2017. The median age of the patients was 59 years (range, 31–75 years), and the median follow-up duration was 67.2 months (range, 10.2–130.5 months). Of the 43 patients, 26 were male and 17 were female. Thirty-four cases were metastatic bone tumors, 5 were chordomas, 3 were osteosarcomas, and 1 was a giant cell tumor. Pain and functional ability of the patients were evaluated using a visual analog scale (VAS) and the Musculoskeletal Tumor Society (MSTS) functional scoring system, respectively. Scores were recorded preoperatively, 1 week postoperatively, and 4 weeks postoperatively. The 1-year, 2-year, and 5-year survival rates were evaluated using the Kaplan-Meier method. Results: The mean VAS score was 8.21 preoperatively. The mean VAS score at 1 week, 4 weeks, 12 weeks, and 24 weeks postoperatively were 3.91, 3.67, 3.31, and 3.12, respectively. The mean preoperative MSTS score was 64.0% (range, 32%–87%). The mean postoperative MSTS score was 71.0% (range, 40%–90%). The 1-year, 2-year, and 5-year survival rates were 95.3%, 69.8%, and 30.2%, respectively. Conclusions As per our study findings, RFA was effective in reducing pain and improving functional ability of patients with bone tumors that were difficult to radically excise.