The Prognostic Significance of Surgical Treatment for Excessive Elderly Soft Tissue Sarcoma Patients Over 90 Years Old: A Clinicopathological Study of 16 Cases.

OBJECTIVES: The incidence of soft tissue sarcomas (STS) among older patients is increasing. Although surgical treatment of elderly patients with STS has been reported to improve their prognosis, most of these studies included patients with STS aged < 85 years. This study aimed to analyze the clinical features and prognostic factors of STS in elderly patients aged ≥ 90 years. SUBJECT AND METHODS: We retrospectively identified patients aged ≥ 90 years with STS who were treated at our two hospitals between 1994 and 2022. Data on clinical information and detailed assessments were collected. We evaluated the features and factors affecting the prognosis of patients with older-extremity STS. In addition, we compared the clinical courses and results of patients treated with surgery and radiotherapy for primary tumors. RESULTS: Among 454 patients with STS, 16 were aged ≥ 90 years. Kaplan-Meier curves for overall survival showed a significantly poorer prognosis in patients who did not receive surgical treatment (p = 0.0348) and those who received radiotherapy (p = 0.0070). Moreover, we investigated the difference in prognosis between surgical treatment and radiotherapy, excluding two cases with distant metastasis at initial diagnosis and one case with no treatment. Kaplan-Meier curves for overall survival showed a significantly better prognosis in patients who underwent surgical treatment (p = 0.0161). Univariate analysis revealed that only primary tumor size was a significant predictor of poor prognosis (p = 0.0426). CONCLUSION: In patients with STS aged ≥ 90 years old, aggressive surgical treatment may improve the prognosis more than radiotherapy.

Effect of Acridine Orange and Zoledronic Acid on Bone Metastasis in Renal Cell Carcinoma.

BACKGROUND/AIM: The increasing incidence of renal cell carcinoma (RCC) and its associated bone metastasis pose challenges in surgical interventions, warranting the exploration of novel therapeutic approaches. Therefore, this study aimed to assess the impact of hematogenously administering acridine orange (AO) alone and in combination with zoledronic acid (ZA) on bone metastasis in RCC. MATERIALS AND METHODS: RENCA cells (1.0×106 cells/10 µl) were directly injected into the right femur of male BALB/c mice. The mice were categorized into four groups based on the applied therapeutic intervention and were euthanized after five weeks. Micro-computed tomography was performed to quantify the extent of periosteal reaction, indicative of bone metastasis, along the entire length of the femur. Tumor weight and volume were measured at euthanization. Hematoxylin and eosin staining was used to examine the extent of tumor development in the bone. Apoptotic cell, osteoclast, and vascular endothelial growth factor (VEGF)-positive cell counts were assessed using TdT-mediated dUTP-biotin nick end labeling, tartrate-resistant acid phosphatase staining, and VEGF staining, respectively. RESULTS: The periosteal reaction was significantly reduced in the intervention groups compared to the control group (p<0.05). The apoptotic cell numbers in the intervention groups surpassed that in the control group (p<0.05), whereas those of osteoclasts and VEGF-positive cells in the intervention groups were lower than those in the control group (p<0.05). CONCLUSION: AO hinders bone metastasis progression in RCC, and combination therapy with ZA may be more effective than AO administration alone.

Development of a New Focal Mouse Model of Bone Metastasis in Renal Cell Carcinoma.

BACKGROUND/AIM: Developing animal models of bone metastasis in renal cell carcinoma (RCC) is challenging as immunodeficient mice are required. The aim of this study was to develop a simple immune model of RCC bone metastasis. MATERIALS AND METHODS: RENCA tumor cells were injected into the right femurs of BALB/c mice. Sixty mice were grouped into each twenty-mouse group according to the tumor cell concentration, and the presence or absence and extent of bone metastasis in the total length of the femur were compared using hematoxylin and eosin staining of the excised tissues. RESULTS: Bone metastasis was significantly higher in the high concentration group than in the other groups (p<0.05), with 10 mice developing bone metastasis at two weeks and nine mice developing bone metastasis at three weeks. The extent of bone metastasis was significantly greater in the high concentration group than in the other groups (p<0.05). Multiple logistic regression analysis was performed to examine the factors influencing bone metastasis, and only the high concentration was a significant factor (p<0.05). CONCLUSION: We developed a normal immunity mouse model of local bone metastasis from RCC. This model could prove valuable for research into the treatment of bone metastases in RCC.

Coefficient of variation of T2-weighted MRI may predict the prognosis of malignant peripheral nerve sheath tumor.

BACKGROUND: We investigated whether non-enhancement MRI features, including measurement of the heterogeneity of the tumor with MR T2 imaging by calculating coefficient of variation (CV) values, were associated with the prognosis of non-metastatic malignant peripheral nerve sheath tumors (MPNST). METHODS: This retrospective study included 42 patients with MPNST who had undergone surgical resection (mean age, 50 years ± 21; 20 male participants). Non-enhancement MR images were evaluated for signal intensity heterogeneity on T1- and T2-weighted imaging, tumor margin definition on T1- and T2-weighted imaging, peritumoral edema on T2-weight imaging, and CV. We measured the signal intensities of MR T2-weighted images and calculated the corresponding CV values. CV is defined as the ratio of the standard deviation to the mean. The associations between factors and overall survival (OS) were investigated via the Kaplan-Meier method with log-rank tests and the Cox proportional hazards model. RESULTS: The mean CV value of MR T2 images was 0.2299 ± 0.1339 (standard deviation) (range, 0.0381-0.8053). Applying receiver operating characteristics analysis, the optimal cut-off level for CV value was 0.137. This cut-off CV value was used for its stratification into high and low CV values. At multivariate survival analysis, a high CV value (hazard ratio = 3.63; 95% confidence interval = 1.16-16.0; p = 0.047) was identified as an independent predictor of OS. CONCLUSION: The CV value of the signal intensity of heterogenous MPNSTs MR T2-weighted images is an independent predictor of patients' OS.

Factors Affecting the Second Complete Atypical Femoral Fracture after the First Atypical Fracture.

OBJECTIVES: Atypical femoral fracture (AFF) is an atypical low-energy subtrochanteric and diaphyseal femoral fracture. Even if bone fusion is achieved in patients with AFF, the risk of AFF in the contralateral femur must be considered. This study aimed to investigate the factors affecting complete AFF in the contralateral femur and conservatively treated incomplete AFF. SUBJECT AND METHODS: Radiographs of 111 femurs in 104 AFF cases were examined, and the femurs were classified as follows: 85 contralateral femurs with complete AFF; 18 contralateral femurs with incomplete AFF; 8 femurs with incomplete AFF without surgical treatment. Various patients' clinical data were collected, and we investigated the factors affecting the second complete AFF. RESULTS: Complete fractures occurred in 10 (9.7%) of 103 femurs without incomplete AFF at the first visit and in 3 (37.5%) of 8 femurs with incomplete AFF. The Kaplan-Meier curve revealed that lateral cortical bone thickening and thigh pain were associated with significantly poorer prognoses (p = 0.026 and p = 0.013, respectively). Multivariate analyses revealed that eldecalcitol usage after AFF onset (p = 0.0094) and previous use of bisphosphonate or denosumab (p = 0.0126) were protective factors for second complete AFF and that the presence of thigh pain (p = 0.0134) was a risk factor for second complete AFF. CONCLUSIONS: Eldecalcitol administration after bone union of first AFF may prevent AFF recurrence. In addition, painful incomplete AFF has a high risk of developing a complete fracture.

Effects of bisphosphonates and treadmill exercise on bone and kidney in adenine-induced chronic kidney disease rats.

INTRODUCTION: The increasing prevalence of osteoporosis and chronic kidney disease (CKD) due to the aging of society has highlighted the need for development of effective treatments for elderly patients. This study examined whether the combination of treadmill exercise therapy and alendronate (ALN) can improve bone mineral density (BMD) and bone strength without worsening renal function in adenine-induced CKD model rats. MATERIALS AND METHODS: 8-week-old male Wistar rats (n = 70) were divided into experimental groups based on the treatment protocol, i.e., non-CKD (control), vehicle only (CKD), ALN only, exercise only, and combined ALN plus exercise. A 0.75% adenine diet was used to induce CKD. Groups were killed at either 20 or 30 weeks of age. Comprehensive assessments included serum and urine biochemistry tests, renal histology, bone histomorphometry, BMD measurement, micro-computed tomography examinations, and biomechanical testing. RESULTS: Blood biochemistry tests, urine analyses and histological evaluations of the kidney demonstrated that ALN treatment did not worsen renal function or kidney fibrosis in moderate-stage CKD model rats. Both ALN and treadmill exercise significantly suppressed bone resorption (p < 0.05-p < 0.01). Moreover, ALN monotherapy and combined ALN and treadmill exercise significantly improved BMD of the lumbar spine and femur, bone microstructure, and trabecular bone strength (p < 0.05-p < 0.01). Treadmill exercise was also shown to decrease cortical porosity at the mid-diaphysis of the femur and improve kidney fibrosis. CONCLUSION: The combination of ALN and treadmill exercise is effective in improving BMD, the microstructure of trabecular and cortical bone, and bone strength, without compromising renal function in adenine-induced CKD model rats.

Effects of Soft Tissue Sarcoma and Doxorubicin on Bone Metabolism in Mice.

BACKGROUND/AIM: This study aimed to evaluate the effects of doxorubicin (Dox) on bone microstructure and metabolism in a mouse model of soft tissue sarcoma. MATERIALS AND METHODS: CCRF S-180II cells (2-4×105 cells/0.2 ml) were injected subcutaneously into the back of mice. The mice were divided into four groups according to tumor and treatment status and were reared and sacrificed after 2 or 4 weeks. Micro-computed tomography (CT) was performed to calculate the architecture of the femoral bone. The proximal tibia was double stained with tartrate-resistant acid phosphatase (TRACP) and alkaline phosphatase (ALP), and bone morphometry was performed. RESULTS: Trabecular bone mass was significantly reduced in the Sarcoma and Sarcoma+Dox groups. Cortical bone thickness was reduced in the DOX group, with a stronger effect observed in the Sarcoma+Dox group. In bone morphometry, osteoclast number at the bone surface (Oc.N/BS) was significantly lower in the Dox, Sarcoma, and Sarcoma+Dox groups than in the Control group at 2 weeks. The osteoblast surface at the bone surface (Ob.S/BS) was significantly lower in the Dox and Sarcoma groups than in the Control group at 2 weeks. At 4 weeks, the differences were smaller for both Oc.N/BS and Ob.S/BS. CONCLUSION: The use of doxorubicin alone worsened the cortical bone structure; however, the presence of both soft-tissue sarcoma and doxorubicin use worsened both cortical and trabecular bone structures from an early stage.

Soft Tissue Tumor Without Neurofibromatosis Type 1 With Histopathological Suspicion of Atypical Neurofibromatous Neoplasm of Uncertain Biological Potential (ANNUBP).

Atypical neurofibromatous neoplasm of uncertain biological potential (ANNUBP), defined as a borderline lesion that is difficult to distinguish whether benign or malignant, is one of the intermediate stages to malignant peripheral nerve sheath tumor, a peripheral nerve-derived malignant tumor that develops from nerve sheath cells. Because ANNUBP is a new concept, only a few cases have been reported, all in patients with neurofibromatosis type 1 (NF-1).An 88-year-old woman presented with a mass on the left upper arm persisting for one year. Magnetic resonance imaging showed a large tumor spreading between the humerus and biceps muscle, which was diagnosed as undifferentiated pleomorphic sarcoma by needle biopsy. Extensive tumor resection was performed, including partial cortical bone resection of the humerus. Based on the histological features, although the patient did not have NF-1, the tumor was strongly suspected to be ANNUBP. As malignant peripheral nerve sheath tumors have been sporadically reported in patients without NF-1, it is feasible that ANNUBP could also occur in patients without NF-1.

Comparison of the Continuation Rate of Twice-Weekly and Weekly Teriparatide Administration in a Rural Area.

Teriparatide plays an important role in the treatment of patients with severe osteoporosis; however, it is meaningless if patients cannot continue. In recent years, the use of a twice-weekly auto-injector teriparatide preparation has become possible. However, its continuation rate and the factors affecting it have not been adequately investigated. Therefore, this study aimed to examine the continuation rate of twice-weekly teriparatide and the factors affecting it. This retrospective study included 143 patients who were administered teriparatide weekly (65 patients) or twice-weekly (78 patients) in a rural hospital. Patient information, such as age, the distance between the hospital and home, family structure, past osteoporosis treatment and fracture, adverse events, and period of teriparatide continuation, were collected. We compared the differences in continuation rates between the twice-weekly and the weekly groups using the Kaplan-Meier curves, and we examined factors influencing teriparatide discontinuation using multivariate analyses. The 12- and 24-month continuation rates of twice-weekly administration of teriparatide were 79.5% and 61%, respectively. The twice-weekly group showed a significantly higher continuation rate (P < 0.0001). The multivariate analyses showed that older age and adverse events were identified as risk factors negatively influencing teriparatide continuation (P = 0.0237 and P < 0.0001, respectively). On the other hand, twice-weekly teriparatide was shown to reduce the risk of discontinuation (P = 0.0043). The twice-weekly teriparatide has a considerably higher continuation rate than the weekly teriparatide. Weekly preparation, older age, and adverse event were identified as risk factors negatively influencing teriparatide continuation.

Macrophage numbers in the marginal area of sarcomas predict clinical prognosis.

Even when treated comprehensively by surgery, chemotherapy, and radiotherapy, soft-tissue sarcoma has an unfavorable outcome. Because soft-tissue sarcoma is rare, it is the subject of fewer clinicopathological studies, which are important for clarifying pathophysiology. Here, we examined tumor-associated macrophages in the intratumoral and marginal areas of sarcomas to increase our knowledge about the pathophysiology. Seventy-five sarcoma specimens (not limited to a single histological type), resected at our institution, were collected, and the number of CD68-, CD163-, and CD204-positive macrophages in the intratumoral and marginal areas was counted. We then performed statistical analysis to examine links between macrophage numbers, clinical factors, and outcomes. A high number of macrophages positive for all markers in both areas was associated with worse disease-free survival (DFS). Next, we divided cases according to the FNCLCC classification (Grade 1 and Grades 2/3). In the Grade 1 group, there was no significant association between macrophage number and DFS. However, in the Grade 2/3 group, high numbers of CD163- and CD204-positive macrophages in the marginal area were associated with poor DFS. By contrast, there was no significant difference between the groups with respect to high or low numbers of CD68-, CD163-, or CD204-positive macrophages in the intratumoral area. Multivariate analysis identified the number of CD163- and CD204-positive macrophages in the marginal area as an independent prognostic factor. Macrophage numbers in the marginal area of soft-tissue sarcoma may better reflect clinical behavior.

Teriparatide and etelcalcetide improve bone, fibrosis, and fat parameters in chronic kidney disease model rats.

Objectives: Chronic kidney disease (CKD) complicated by secondary hyperparathyroidism (SHPT) is associated with an increased risk of fragility fractures. Etelcalcetide (EC) is a treatment for SHPT that reduces serum parathyroid hormone (PTH) levels. However, the effects of combined treatment with osteoporosis drugs such as teriparatide (TPTD) remain unclear. This study investigates the combined effects of EC and TPTD on bone in CKD model rats. Methods: The CKD model was established in 8-week-old male Wistar rats by feeding them a 0.75% adenine diet for 4 weeks. At 20 weeks of age, the rats were divided into 4 groups (N = 9-10 in each group): CKD group (vehicle administration), TPTD group (30 µg/kg, 3 times/week), EC group (0.6 mg/kg, daily), and Comb group (TPTD and EC combined). EC was injected for 12 weeks starting at 20 weeks of age, and TPTD was injected for 8 weeks starting at 24 weeks of age. After treatment, the followings were evaluated: bone mineral density, bone strength, biochemical tests, bone and fat histomorphometry, and micro-computed tomography. Results: In CKD model rats, the combination of EC and TPTD was more effective in increasing cortical bone thickness and bone strength and inhibiting porosity. In addition, the combined treatment decreased bone marrow adiposity and fibrosis, and it increased bone mass and improved bone microstructure in trabecular bone. Conclusions: With the observed benefits such as improved bone mass, bone strength, structural properties, and bone marrow adiposity, combination therapy may be a potential way to improve bone fragility in CKD.

Intravascular Administration of Acridine Orange and Zoledronate in a Bone Metastasis Model of Breast Cancer.

BACKGROUND/AIM: This study evaluated the effect of haematogenous administration of acridine orange (AO) alone and in combination with zoledronate (ZOL) on bone metastases. MATERIALS AND METHODS: E0771 cells (1.0×105 cells/10 µl) were injected directly into the right femur of female mice. The mice were divided into five groups according to treatment (drugs and irradiation) and were reared and sacrificed after 6 weeks. Micro-computed tomography (µCT) was performed to calculate the destruction rate of the femur bone. We measured tumour weight and volume at sacrifice and performed terminal deoxynucleotidyl transferase dUTP Nick-End Labelling staining of tumours. RESULTS: At 4 weeks, the bone destruction rate was lower in the AO+ZOL group than in the radiation group. At 6 weeks, the AO+ZOL group had a lower bone destruction rate than the control and radiation groups; the ZOL group had a lower rate than the radiation group. The AO and AO+ZOL groups had suppressed tumour weight and volume compared to the control and radiation groups. The number of extraosseous apoptotic cells was higher in the AO+ZOL group than in all other groups except the AO group. CONCLUSION: In a model of local bone metastasis of breast cancer, haematogenous administration of AO reduced tumour size and more so when combined with ZOL.

Risk Factors of Early Distant Metastasis After Primary Tumor Treatment in Soft Tissue Sarcoma.

BACKGROUND/AIM: Distant metastasis has a strong influence on prognosis in patients with soft tissue sarcoma (STS). While various risk factors have been reported for distant metastases, risk factors for distant metastases early after treatment of primary tumor have not been investigated. This study aimed to evaluate the factors of early distant metastasis after primary tumor resection in patients with STS. PATIENTS AND METHODS: We retrospectively identified patients with STS involving the extremities or trunk without any metastasis at the first visit. Data on clinical information and detailed assessment were collected. We evaluated clinical information as a risk factor for distant or lung metastases. Additionally, we evaluated risk factors for metastases in patients with distant metastases as early as 6 months after the initial resection of the primary tumor. RESULTS: A total of 337 patients were included in the study. Multivariate analysis revealed that the size of the primary tumor (p=0.0011 and p=0.0167), consultation in a short period after onset (p=0.0325 and p=0.0402), histological high grade (p=0.0006 and p=0.0002), and inadequate surgical margin (p=0.0151 and p=0.0055) were significant predictors for poor prognosis for all distant and lung metastases, respectively. However, the only risk factor for early metastases within 6 months was young age (p=0.0148). CONCLUSION: The only risk factor for early distant metastasis after primary tumor resection in patients with STS was young age, even though large tumor diameter and histological high grade were risk factors for distant metastasis.

Successful Treatment of Atypical Femoral Fracture with Bowed Femur Using Contralateral Intramedullary Nail Combined with Early Daily Teriparatide.

We report a case of atypical femoral fracture achieving early fracture union with combination therapy comprising contralateral nail and immediate teriparatide injection. Fracture union of atypical fractures is often delayed due to bowing deformity and bone metabolic disorders. Combination treatment that takes both problems into consideration represents a useful treatment option for atypical femoral fracture.

Non-ossifying fibromas and fibrous cortical defects around the knee - an epidemiologic survey in a Japanese pediatric population.

BACKGROUND: The aim of the present study was to evaluate the prevalence of non-ossifying fibroma (NOF) and fibrous cortical defect (FCD) in a Japanese pediatric population and the association between the lesion size and pain. METHODS: This retrospective study, conducted across 10 Japanese institutions, included patients aged 5-15 years who had undergone standard antero-posterior and lateral view radiography of the knee. Using these radiographs, we diagnosed the lesion as a NOF or FCD. Patient demographics, including age, sex, the size and location of the NOF, and chief complaint were recorded. The lesion size was determined using radiographs. Student's t-test was used to compare the associations between the lesion size and spontaneous pain. RESULTS: A total of 6222 subjects (3567 boys and 2455 girls) were included in this study. The number of NOF and FCD cases was 143 and 437, respectively, and the prevalence of NOF and FCD was 2.3% and 7.0%, respectively. The average size of NOF and FCD was 22.1 mm (range: 4-102 mm) and 13.2 mm (range: 5-21 mm), respectively. Three patients (2.1%) had pathological fractures due to NOF. Of the 140 NOFs and 437 FCDs, we obtained complaints from the medical records of 126 and 393 patients, respectively. The number of patients with spontaneous pain or other problems with NOF was 68 (54%) and 58 (46%), respectively, that of patients with FCD was 195 (50%) and 198 (50%) patients, respectively. The lesion size was not associated with spontaneous pain in either lesion (p = 0.67 and p = 0.27, respectively). CONCLUSION: The prevalence of NOF and FCD around the knee was lower than that reported in previous studies. The prevalence of NOF increased and that of FCD decreased with advancing age. In both lesions, the lesion size may not be associated with pain.

Development of New Mouse Breast Cancer Model of Local Bone Metastasis and Verification Using Bisphosphonates.

BACKGROUND/AIM: Local tumor injection models require complicated procedures. The purpose was to establish a simple local bone metastasis model using normal mice, and to study the usefulness of the model with bisphosphonates (BP). MATERIALS AND METHODS: This study used a versatile C57BL/6 mouse model and E0771 cells. Tumor cells were injected into the right femur. Mice were divided into groups depending on the concentration of cells injected and the use of BP or not. The degree of bone destruction between the different conditions was compared using micro-computed tomography (µCT). RESULTS: Bone destruction was confirmed in four mice in the high-concentration group at 3 weeks, and in all other mice at 4 and 6 weeks. At 6 weeks post-injection, bone destruction was significantly suppressed in the BP group (p<0.05). CONCLUSION: We created a breast cancer mouse model of local bone metastasis. Zoledronate showed the same usefulness as in previous models. It may be an effective model for evaluating treatments for bone metastasis.

Effects of teriparatide and low-intensity aerobic exercise on osteopenia in type 2 diabetes mellitus rats.

INTRODUCTION: In patients with type 2 diabetes mellitus (T2DM), bone fragility increases fracture risk. Teriparatide (TPTD) improves bone strength, and exercise therapy suppresses blood glucose levels in T2DM. In this study, the combined effects of TPTD and exercise therapy on trabecular and cortical bone were examined in advanced T2DM model rats. MATERIALS AND METHODS: Thirty-week-old Otsuka Long-Evans Tokushima Fatty rats were divided into four groups (n = 9-10 in each group at two time points): Cont group (vehicle-treated control), TPTD group (TPTD 30 µg/kg injected subcutaneously, 3 times/week), Exe group (treadmill exercise, 10 m/min, 60 min/day, 5 times/week), and Comb group (TPTD-treated and treadmill exercise combined). Five and 10 weeks after treatment, bone mineral density (BMD), bone strength, and bone micro-architecture were measured. RESULTS: TPTD and combined treatment significantly increased BMDs of the lumbar spine and femur compared to the Cont group (p < 0.05 to p < 0.01). In the three-point bending test of the femur, only combined treatment increased the maximum load at 5 weeks compared with the Cont and Exe groups (p < 0.01). In the compression test of the distal femoral metaphysis, both TPTD and combined treatment increased the trabecular bone strength compared with the Cont and Exe groups (p < 0.05 to p < 0.01). Although TPTD and combined treatment improved the micro-architecture of trabecular bone (p < 0.05 to p < 0.01), only combined treatment improved the micro-structures of cortical bone from 5 weeks of treatment (p < 0.05 to p < 0.01). CONCLUSION: The combination of TPTD and treadmill exercise increased BMD and trabecular and cortical bone strength of the femur with improved micro-architecture in T2DM model rats.

Guideline-based Treatment of Glucocorticoid-induced Osteoporosis in Patients with Rheumatoid Arthritis: A Retrospective Study with the AORA Registry.

Glucocorticoid-induced osteoporosis (GIOP) is one of the side effects associated with glucocorticoid (GC) therapy. In 2014, the Japanese Society for Bone and Mineral Research (JSBMR) provided new guidelines for the management and treatment of GIOP. The aim of the present study was to clarify the prevalence of patients with rheumatoid arthritis (RA) requiring treatment according to the new guidelines and to identify risk factors associated with lack of treatment in these patients. Patients in the 2018 Akita Orthopedic group on Rheumatoid Arthritis (AORA) database were enrolled. Of 2,234 patients with RA in the database, 683 (30.6%) met the 2014 JSBMR guideline treatment criteria, and 480 (70.3%) had been treated. The untreated group included a larger number of males, younger patients, and patients treated in clinics rather than hospital (p<0.001, p=0.015, and p<0.001, respectively). Multivariate analyses found that male sex, younger age, and clinic-based RA care were significant risk factors associated with lack of treatment (p<0.001, p=0.013, and p<0.001, respectively). Thus, male sex, younger age, and clinic-based care were identified as risk factors.

Deep Angiomyxoma of the Thigh That Is Difficult to Diagnose: A Case Report and Literature Review.

We present an extremely rare case of deep angiomyxoma (DAM) in the thigh that was misdiagnosed as desmoid-type fibromatosis. A 40-year-old Japanese woman presented with a mass on the left thigh. The histological diagnosis by needle biopsy was desmoid-type fibromatosis; the tumor grew slowly and was resected 4 years later. The histological diagnosis from the resected tumor was DAM. As of 16 months post-surgery, the patient has not noticed any local recurrence. Although DAM in a lower extremity is extremely rare, clinicians must be aware of its possible occurrence in areas relatively close to the pelvis.