Optimal reimplantation timing in two-stage exchange for periprosthetic joint infection: an observative cohort study in Asian population.

BACKGROUND: The optimal timing for reimplantation for periprosthetic joint infection (PJI) has not been established and varies from a few weeks to several months. The aim of this study was to assess the commendable time between implant removal and reimplantation in patients who underwent two-stage exchange arthroplasty for PJI. METHODS: We retrospectively reviewed 361 patients who were treated with two-stage exchange arthroplasty for hip and knee chronic PJI at our institution between January 2000 and December 2018. Patient characteristics, comorbidities, surgical variables, microbiology data, and time to reimplantation were recorded. All patients were followed for a minimum of one year. Treatment failure was defined by Delphi criteria. Logistic regression analyses were used to calculate survival rates and adjusted odds ratios (ORs) of treatment failure. RESULTS: In final analysis, 27 (7.5%) had treatment failure. Factors related to treatment failure including interim spacer exchange (OR, 3.13; confidence interval (CI), 1.04-9.09, p = 0.036), higher ESR level at reimplantation (OR, 1.85; CI, 1.05-3.57; p = 0.04), and time to reimplantation (OR, 1.00; CI, 1.003-1.005, p = 0.04). Performing revision arthroplasty surgery from 16 to 20 weeks had highest successful rate. The reimplantation over 24 weeks had a lower successful rate. However, no statistical significance in comparing each interval group. CONCLUSION: Our study emphasized the importance of timely reimplantation in achieving successful outcomes. Factors such as ESR levels, spacer exchange, and the duration of time to reimplantation influenced the likelihood of treatment failure in two-stage exchange arthroplasty for hip and knee PJI.

Comparison of the radiographic outcomes and total blood loss between pinless navigation and conventional method in minimally invasive total knee arthroplasty.

BACKGROUND: Computer-assisted surgical navigation has been used in total knee arthroplasty (TKA) procedures for years trying to the accuracy of prosthesis placement. We conducted this prospective randomized clinical trial to compare the accuracy of the radiographic parameters of the prosthesis, total blood loss (TBL), and related complications, between a new pinless navigation system (Stryker OrthoMap Express Knee Navigation) and conventional method in patients undergoing minimally invasive (MIS) TKA procedures. PATIENT AND METHODS: A consecutive series of 100 patients underwent unilateral primary TKA were randomly assigned into two groups: navigation group and convention group. The radiographic parameters of the knee implant and the alignment of lower limb were measured at 3 months after surgery. TBL was calculated according to Nadler's method. The duplex ultrasonography of both lower limbs was performed in all patients to detect the presence of deep-vein thrombosis (DVT). RESULTS: Totally, 94 patients have completed the radiographic measures. Only the coronal femoral component angle in the navigation group (89.12° ± 1.83°) had significant differences from that in the convention group (90.09° ± 2.18°) (p = 0.022). There were no differences in the rate of outliers. The mean TBL in the navigation group was 841 ± 267 mL, which was similar to that in the convention group at 860 ± 266 mL (p = 0.721). Postoperative DVT risk did not differ between the two groups (2% vs. 0%, p = 0.315). CONCLUSION: This pinless navigation TKA showed a comparable acceptable alignment compared with conventional MIS-TKA. There were no differences regarding postoperative TBL between the two groups.

Bidirectional association between fibromyalgia and migraine among probands and unaffected non-twin siblings: A nationwide population-based study.

OBJECTIVE: This study explored the bidirectional relationship between fibromyalgia and migraine among probands with either of the two disorders and their unaffected siblings. BACKGROUND: Evidence suggests a bidirectional association between fibromyalgia and migraine in individuals and in twins. However, whether a bidirectional association between fibromyalgia and migraine also occurs among siblings remains unknown. METHODS: Using the Taiwan National Health Insurance Research Database, we examined the data of 2677 probands with fibromyalgia, 2780 unaffected siblings, and 11,120 matched controls to assess the risk of migraine. In contrast, 1830 probands with migraine, 1936 unaffected siblings, and 7744 matched controls to assess the risk of fibromyalgia. RESULTS: Logistic regression analyses demonstrated that patients with fibromyalgia (odds ratio [OR]: 3.69; 95% confidence interval [CI]: 2.87-4.74) and unaffected siblings (OR: 1.51; 95% CI: 1.08-2.10) were more likely to develop migraine than the controls during the follow-up period. Moreover, patients with migraine and unaffected siblings had a 4.86-fold (95% CI: 3.86-6.09) and 1.59-fold (95% CI: 1.18-2.12) increased risk of fibromyalgia than the controls. CONCLUSION: The bidirectional association between fibromyalgia and migraine among probands and unaffected siblings suggests a familial coaggregation of these two conditions. Additional studies are required to investigate the genetic and environmental etiologies for this coaggregation.

Longitudinal Association of Universal Screening and Treatment for Major Depressive Disorder with Survival in Cancer Patients.

Evidence for clinical screening and intervention for depression in cancer and the effect of this intervention on cancer prognosis is suboptimal. This study substantialized a complete model with universal screening and intervention for major depressive disorder (MDD) and explored its effect on survival in patients. This longitudinal study recruited cancer patients routinely screened for MDD with a two-stage model. Data including sex, age, cancer diagnosis, first diagnosis date, date of death, cancer stage, and MDD diagnosis and treatment were collected from medical records and the national registration system for cancer. Kaplan−Meier's survival analysis and the Cox proportional hazards regression model were applied to analyze the effects of associated factors on survival. Further subgroup analysis for 14 types of cancer primary site was also performed. Overall, the hazard for patients adhering to psychiatric treatment for MDD before cancer diagnosis was not statistically different from that for patients without MDD (hazard ratio (HR) = 1.061, 95% CI: 0.889−1.267, p = 0.512). The hazard for patients adhering to psychiatric treatment after cancer diagnosis was significantly lower than that for patients without MDD (HR = 0.702, 95% CI: 0.607−0.812, p < 0.001). Those who were diagnosed with MDD after cancer diagnosis and adhered poorly to psychiatric treatment had the greatest hazard (HR = 1.829, 95% CI: 1.687−1.984, p < 0.001). The effect of intervention for MDD varied across different primary cancer types.

Comparison of Effects of a Thrombin-Based Hemostatic Agent and Topical Tranexamic Acid on Blood Loss in Patients with Preexisting Thromboembolic Risk Undergoing a Minimally Invasive Total Knee Arthroplasty. A Prospective Randomized Controlled Trial.

BACKGROUND: The efficacy of a thrombin-based hemostatic agent (Floseal®) on reducing postoperative blood loss after total knee arthroplasty (TKA) was still unclear. The aim of our study was to conduct a prospective randomized controlled study to compare the blood conservation effects of Floseal® and topical TXA in patients with preexisting thromboembolic risk undergoing primary minimally invasive TKA. METHODS: Our power analysis of this study was based upon the following description, to obtain a statistical power of 0.90 and an alpha error of 0.05, 30 patients were required in each group. Therefore, we enrolled a total of 103 patients with at least one of the risk factors for thromboembolism who underwent unilateral primary minimally invasive TKA, and the participants were randomly divided into the topical TXA group (n = 34), receiving intra-articular injection of 3 g of TXA in 100 mL saline after TKA, the topical Floseal® group (n = 34), receiving 10 mL of Floseal® intra-articularily during surgery, and the placebo group (n = 35), receiving an intra-articular saline injection only. The total blood loss (TBL) and hemoglobin (Hb) drop were compared among the 3 groups. RESULTS: The TXA group had a lower TBL of 645 mL (227 to 1090) in comparison with 1145 mL (535 to 1942) in the Floseal® group and 1103 mL (424 to 1711) in the placebo (p < 0.001, respectively). The TBL was similar between the Floseal® group and the placebo group (p = 0.819). No patients in any group had symptoms of venous thromboemblism. CONCLUSION: Our prospective randomized controlled study showed that intra-articular application of TXA was superior to hemostatic matrix (Floseal®) in terms of blood conservation in patients with preexisting thromboembolic risk undergoing minimally invasive TKA. This trial is registered with Clinicaltrials.gov (NCT02865174) on 08/09/2016.

RSF1 requires CEBP/ß and hSNF2H to promote IL-1ß-mediated angiogenesis: the clinical and therapeutic relevance of RSF1 overexpression and amplification in myxofibrosarcomas.

Myxofibrosarcoma is genetically complex and lacks effective nonsurgical treatment strategies; thus, elucidation of novel molecular drivers is urgently needed. Reanalyzing public myxofibrosarcoma datasets, we identified mRNA upregulation and recurrent gain of RSF1 and characterized this chromatin remodeling gene. Myxofibrosarcoma cell lines were employed to elucidate the oncogenic mechanisms of RSF1 by genetic manipulation and two IL-1ß-neutralizing antibodies (RD24, P2D7KK), highlighting the regulatory basis and targetability of downstream IL-1ß-mediated angiogenesis. Tumor samples were assessed for RSF1, IL-1ß, and microvascular density (MVD) by immunohistochemistry and for RSF1 gene status by FISH. In vivo, RSF1-silenced and P2D7KK-treated xenografts were analyzed for tumor-promoting effects and the IL-1ß-linked therapeutic relevance of RSF1, respectively. In vitro, RSF1 overexpression promoted invasive and angiogenic phenotypes with a stronger proangiogenic effect. RT-PCR profiling identified IL1B as a top-ranking candidate upregulated by RSF1. RSF1 required hSNF2H and CEBP/ß to cotransactivate the IL1B promoter, which increased the IL1B mRNA level, IL-1ß secretion and angiogenic capacity. Angiogenesis induced by RSF1-upregulated IL-1ß was counteracted by IL1B knockdown and both IL-1ß-neutralizing antibodies. Clinically, RSF1 overexpression was highly associated with RSF1 amplification, IL-1ß overexpression, increased MVD and higher grades (all P ≤ 0.01) and independently predicted shorter disease-specific survival (P = 0.019, hazard ratio: 4.556). In vivo, both RSF1 knockdown and anti-IL-1ß P2D7KK (200 µg twice weekly) enabled significant growth inhibition and devascularization in xenografts. In conclusion, RSF1 overexpression, partly attributable to RSF1 amplification, contributes a novel proangiogenic function by partnering with CEBP/ß to cotransactivate IL1B, highlighting its prognostic, pathogenetic, and therapeutic relevance in myxofibrosarcomas.

Extended Postoperative Prophylactic Antibiotics with First-Generation Cephalosporin Do Not Reduce the Risk of Periprosthetic Joint Infection following Aseptic Revision Total Knee Arthroplasty.

Postoperative prophylactic antibiotics administered within 24 hours of primary total knee arthroplasty (TKA) have been documented to prevent periprosthetic joint infection (PJI). However, the effectiveness of this regimen is still unclear in aseptic revision TKA. The purpose of this study was to evaluate whether extended postoperative prophylactic antibiotics would reduce the PJI rate compared with the current 24-hour standard postoperative prophylactic antibiotics after aseptic revision TKA. A retrospective review of 236 patients (46 men, 190 women, 252 knees) who underwent aseptic revision TKA between 2005 and 2013 was conducted. Patients who underwent septic revision, had a positive intraoperative culture, or who had less than 2 years of follow-up were excluded. Patients were divided according to the duration of postoperative prophylactic antibiotics to standard group (76 knees, ≤ 24 hours) or extended group (176 knees, > 24 hours). PJI was determined by the Musculoskeletal Infection Society criteria. A multivariate Cox proportional hazards regression analysis was performed. The mean follow-up was 5.2 ± 2.5 years. Patients with extended postoperative prophylactic antibiotics had a lower PJI rate (1.1%) compared with standard group (3.9%), but the difference was not statistically significant (p = 0.14). Body mass index ≥ 30 kg/m2 was the only independent risk factor of PJI (adjusted hazard ratio [HR]: 9.59; 95% confidence interval [CI]: 1.07-86.04, p = 0.043). The use of extended postoperative prophylactic antibiotics was not a risk factor for PJI (adjusted HR: 0.34; 95% CI: 0.06-2.04, p = 0.238). After 10 years, the two groups had similar infection-free implant survival rate (95.9 vs. 98.9%, p = 0.15). Our findings demonstrate that extended postoperative prophylactic antibiotics did not reduce PJI rate compared with the standard group in aseptic revision TKA. A further prospective, randomized study with a standardized postoperative antibiotic protocol is necessary to address this topic. Level of evidence is prognostic Level III.

Correction to: Treatment of cam-type femoroacetabular impingement using anterolateral mini-open and arthroscopic osteochondroplasty.

In the original publication of this article [1], the first name of the 5th author is wrong.

Treatment of cam-type femoroacetabular impingement using anterolateral mini-open and arthroscopic osteochondroplasty.

BACKGROUND: Femoroacetabular impingement (FAI) is associated with decreased hip function and early hip osteoarthritis. Surgical treatment is often required to halt the process of mechanical degeneration. The study investigated the short-to-midterm results of using a modified anterolateral mini-open and arthroscopic osteochondroplasty in the treatment of cam-type FAI. METHODS: Thirty-six patients (39 hips), with the mean age of 43.6 years, who had cam-type FAI, were operated by a mini-open and arthroscopy-assisted osteochondroplasty via the Watson-Jones interval between 2002 and 2016. Radiographic parameters and Harris hip scores were retrospectively analyzed after a mean follow-up of 44 months. RESULTS: Of the 39 hips, the mean Harris hip score significantly improved from 61.1 preoperatively to 84.2 postoperatively (P < 0.01). There were nine hips (23%) undergoing total hip arthroplasty (THA) at a mean of 22 months (range, 3~64 months) due to progression of hip osteoarthritis. The 5-year survival for hip preserving was 74.9%. Cox proportional-hazards model showed that age ≥ 55 years (P = 0.03) and preoperative Tönnis stage II (P = 0.02) were independent risk factors for conversion to THA. CONCLUSIONS: The mini-open and arthroscopic approach allowed direct visualization and improved quality of the osteochondroplasty of FAI hip while avoiding the need for surgical dislocation. This technique could be a safe and viable option for symptomatic cam-type FAI patients to relieve symptoms and improve hip function.

Fracture of cobalt chrome, fully-coat beaded femoral revision long stem, a clinical outcomes study.

BACKGROUND: Femoral bone loss during revision total hip arthroplasty poses a challenging problem. Bypass fixation over the diaphysis has achieved clinical success in cases of proximal femoral bone loss. Fracture of cementless, fully bead-coated femoral stem is an uncommon complication. The purpose of this study is to analyze the patients with and without fracture stem and find out the possible risk factors. METHODS: From 2006 to 2012, a total of 251 revision long stems (Zimmer, Warsaw, IN) were implanted. In the same period, 17 broken stems that underwent treatment were included for analysis. Patients' demographic data, pattern of femoral bone loss, stem size, medial calcar support in the proximal region of the stem, and the timing of stem breakage were collected and analyzed. RESULTS: The stem size in patients with a broken stem was smaller (p < 0.001), and medial calcar defect was 12.4% and 100% (p < 0.001), respectively. The bone defect was greater in broken group (p = 0.024). The mean duration between revision surgery and stem breakage was 58.07 ± 36.98 months. Smaller stem size, greater bone defect, and inadequate medial calcar bone support were major risk factors for stem breakage. CONCLUSIONS: Bypass fixation in the distal diaphysis with a long stem prosthesis without adequate bone support over medial calcar area may cause stress concentration in the long stem and a fatigue fracture. Use of a smaller prosthesis is the major risk of stem broken. It is essential to repair the proximal femoral bone deficiency and implant selection for better metaphyseal engagement to prevent further stem complications. LEVEL OF EVIDENCE: Level III, case control study.

A 10-Year Follow-Up of Two-Incision and Modified Watson-Jones Total Hip Arthroplasty in Patients with Osteonecrosis of the Femoral Head.

Long-term data and information indicating whether minimally invasive surgery (MIS) approaches are safe and effective with total hip arthroplasty (THA) are lacking. Between 2004 and 2006, 75 patients with alcohol-related osteonecrosis of the femoral head (ONFH) who underwent 75 THAs with the two-incision approach were studied. The medical records, radiographic parameters, and functional outcomes were collected prospectively. All data were compared with those for matched patients who underwent a modified Watson-Jones (WJ) approach. THA using the two-incision approach was associated with longer operation time, more blood loss, more lateral femoral cutaneous nerve injury, and more periprosthetic femoral fractures (p < 0.05 for all four) than the modified WJ approach. The Harris Hip Score (HHS) and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) increased significantly from the period preoperatively to 6 weeks postoperatively and thereafter up to the last follow-up in both groups. However, there were no significant differences in terms of radiographic parameters and functional outcomes between the two groups throughout the study period. Both the two-incision and the modified WJ approach provided satisfactory results and survival rates at a mean follow-up of 10.8 years. A prospective, randomized, large-scale cohort study is still warranted for evidence-based recommendations.

Chronic Kidney Disease Is an Independent Risk Factor for Transfusion, Cardiovascular Complication, and Thirty-Day Readmission in Minimally Invasive Total Knee Arthroplasty.

BACKGROUND: Little is known about the relationship between chronic kidney disease (CKD) and minimally invasive total knee arthroplasty (MIS-TKA). We hypothesized that CKD was an independent risk factor for postoperative complications and increased blood transfusion in patients following MIS-TKA. METHODS: A retrospective review of a prospective database was conducted on patients who underwent MIS-TKAs at an academic medical center between 2009 and 2012. Glomerular filtration rates (GFRs) were calculated for each patient at the time of surgery and a CKD group of 205 patients (GFR < 60 mL/min) were matched at a ratio of 1:2 with 410 patients showing a GFR ≥ 60 mL/min (control group). There were no differences between the 2 groups regarding age, gender, body mass index, and American Society of Anesthesiologists grade. Patient characteristics, comorbidities, preoperative hemoglobin, calculated total blood loss, transfusion rate, length of stay, and postoperative complications were compared between the 2 groups. RESULTS: The CKD group had lower preoperative hemoglobin levels; higher preoperative comorbidities with cardiovascular disease, diabetes mellitus, and gout; longer length of stay; and higher total blood loss than the control group. Multivariate logistic regression showed that CKD was an independent risk factor for transfusions (odds ratio [OR] 7.6, 95% confidence interval [CI] 4.79-12.21, P < .001), cardiovascular complication (OR 5.5, 95% CI 1.68-9.39, P = .002), and 30-day readmission (OR 6.2, 95% CI 1.98-12.18, P = .005). CONCLUSION: Based on our data, CKD is an independent risk factor for blood transfusion, cardiovascular complication, and 30-day readmission in patients undergoing MIS-TKA.

The Efficacy of Combined Use of Rivaroxaban and Tranexamic Acid on Blood Conservation in Minimally Invasive Total Knee Arthroplasty a Double-Blind Randomized, Controlled Trial.

BACKGROUND: Tranexamic acid (TXA) was reportedly to decrease postoperative blood loss after standard total knee arthroplasty (TKA). However, the blood-conservation effect of TXA in minimally invasive TKA, in particular, receiving a direct oral anticoagulant was unclear. The aim of the study was to investigate the efficacy of combined use of TXA and rivaroxaban on postoperative blood loss in primary minimally invasive TKA. METHODS: In a prospective, randomized, controlled trial, 198 patients were assigned to placebo (98 patients, normal saline injection) and study group (100 patients, 1g TXA intraoperative injection) during primary unilateral minimally invasive TKA. All patients received rivaroxaban 10 mg each day for 14 doses postoperatively. Total blood loss was calculated from the maximum hemoglobin drop after surgery plus amount of transfusion. The transfusion rate and wound complications were recorded in all patients. Deep-vein thrombosis was detected by ascending venography of the leg 15 days postoperatively. RESULTS: The mean total blood loss was lower in the study group (1020 mL [95% confidence interval, 960-1080 mL]) compared with placebo (1202 mL [95% confidence interval, 1137-1268 mL]) (P < .001). The transfusion rate was lower in the study group compared with placebo (1% vs 8.2%, P = .018). Postoperative wound hematoma and ecchymosis were higher in placebo than the study group (P = .003). There was no symptomatic deep-vein thrombosis or pulmonary embolism in either group. CONCLUSION: Systemic administration of TXA can effectively reduce the postoperative blood loss which results in lower rate of transfusion requirement and wound hematoma in minimally invasive TKA patients when rivaroxaban is used for thromboprophylaxis. Rivaroxaban has a high rate of bleeding complications when used alone in TKA patients.

Topical Tranexamic Acid Reduces Blood Loss in Minimally Invasive Total Knee Arthroplasty Receiving Rivaroxaban.

BACKGROUND: It is unclear whether topical (intra-articular) or intravenous TXA reduces blood loss in minimally invasive TKA patients receiving a direct oral anticoagulant for thromboprophylaxis. This study is to investigate whether TXA given intravenously or intra-articularly is effective in reducing blood loss in minimally invasive TKA patients using rivaroxaban for thromboprophylaxis. METHODS: Ninety-three patients who underwent primary minimally invasive TKA were divided into placebo group (30 patients) that received saline both intravenously and intra-articularly, intravenous (IV) group (31 patients) that received 1 g TXA intravenously, and topical group (32 patients) that received 3 g TXA in 100 ml saline intra-articularly. All patients received oral rivaroxaban of 10 mg daily for 14 days postoperatively. RESULTS: p < 0.001 and p = 0.041. The mean total blood loss was 1131 mL (567-1845) in placebo, which was higher than that in the IV group (921 mL; range, 465-1495; p = 0.014) and the topical group (795 mL; range, 336-1350; p < 0.001). The total blood loss did not differ between the IV and the topical group (p = 0.179). CONCLUSION: This prospective, randomized, controlled trial demonstrated an equal efficacy of TXA in blood conservation when administered intravenously or topically in minimally invasive TKA patients receiving rivaroxaban for thromboprophylaxis.

NAB2-STAT6 gene fusion and STAT6 immunoexpression in extrathoracic solitary fibrous tumors: the association between fusion variants and locations.

Solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm harboring NAB2-STAT6 fusion, which drives STAT6 nuclear relocation. For extrathoracic SFTs, the clinical relevance of this molecular hallmark remains obscure. We assessed STAT6 immunoexpression for 61 extrathoracic SFTs exclusive of the meninges and head and neck, and 25 had analyzable RNAs to distinguish fusion variants by RT-PCR. The immunohistochemical and molecular findings were correlated with clincopathological features and disease-free survival (DFS). Twenty-eight males and 33 females had SFTs in the body cavities (n = 31), extremities (n = 17), and trunk (n = 13), categorized into 53 non-malignant and 8 malignant tumors. The vast majority (n = 57, 93%) exhibited distinctive STAT6 nuclear expression, including malignant ones. The common fusion variants were NAB2ex6-STAT6ex16/17 in 13 SFTs and NAB2ex4-STAT6ex2 in 8, while miscellaneous variants were detected only in 4 SFTs in the limbs and trunk but not in any body cavity-based cases (P = 0.026). The worse DFS was univariately associated with malignant histology (P = 0.04) but unrelated to tumor size, location, or fusion variant. Conclusively, extrathoracic SFTs mostly harbor NAB2ex6-STAT6ex16/17, followed by NAB2ex4-STAT6ex2. Miscellaneous variants are significantly rare in SFTs within the body cavities. The clinical aggressiveness of extrathoraic SFTs is associated with malignant histology but unrelated to the NAB2-STAT6 fusion variants.

Clinicopathological and genetic heterogeneity of the head and neck solitary fibrous tumours: a comparative histological, immunohistochemical and molecular study of 36 cases.

AIMS: Solitary fibrous tumour (SFT) harbours recurrent inv12(q13q13)-derived NAB2-STAT6 fusions, resulting in STAT6 nuclear expression. SFTs affecting the head and neck are rare, for which we reported their clinicopathological, immunohistochemical, and genetic features. METHODS AND RESULTS: With 19 cases assessable for NAB2-STAT6 fusions, 36 head and neck SFTs (18 males; 18 females) diagnosed between 13 and 79 years (median, 47 years) of age were analysed for clinicopathological features and STAT6 immunoexpression. These SFTs, ranging from 5 to 80 mm (median, 25 mm), affected the oral cavity/pharynx (12), orbit (11), sinonasal structures (seven), and somatic soft tissues or skull (six). Histologically, 20 SFTs were conventional, six were giant-cell angiofibroma-like, one was fat-forming, four were cellular/atypical, and five were malignant (two developing metastases). STAT6 distinctively decorated the tumoral nuclei in 35 (97.2%) SFTs, but not in 29 site-relevant histological mimics categorized into 12 entities. Sixteen (84.2%) SFTs showed NAB2-STAT6 fusions with highly heterogeneous exon compositions, including NAB2ex6-STAT6ex17 in four cases, NAB2ex4-STAT6ex2 in three cases, NAB2ex2-STAT6ex2, NAB2ex4-STAT6ex4, NAB2ex6-STAT6ex16 and NAB2ex6-STAT6ex18 in two cases each, and NAB2ex3-STAT6ex19 in one case. CONCLUSIONS: Nuclear STAT6 immunoexpression is sensitive and specific for distinguishing SFT from mimics. However, considerable heterogeneity exists in the head and neck SFTs regarding the locations, histological patterns, and NAB2-STAT6 fusion variants.

The clinicopathological significance of NAB2-STAT6 gene fusions in 52 cases of intrathoracic solitary fibrous tumors.

NAB2-STAT6 gene fusion drives STAT6 nuclear expression and is the pathognomonic hallmark of solitary fibrous tumors (SFTs). However, no study has systematically analyzed the clinicopathological features, STAT6 immunoexpression status, or the fusion variants of NAB2-STAT6 in intrathoracic SFTs. Fifty-two intrathoracic SFTs were retrieved to appraise histopathology, assess STAT6 immunoexpression, and determine NAB2-STAT6 fusion variants by RT-PCR. Location-relevant histologic mimics served as controls. Thirty-one pleura-based, 12 mediastinal/pericardial, and nine intrapulmonary lesions were histologically categorized into eight malignant, eight atypical, and 36 conventional or cellular SFTs, including two fat-forming and two giant cell angiofibroma-like SFTs. STAT6 distinctively decorated the tumoral nuclei in 51 (98%) SFTs. However, no nuclear staining was observed in the histological mimics. NAB2-STAT6 fusion was detected in 34 SFTs. Twenty-nine (85.3%) exhibited the major NAB2ex4-STAT6ex2/3 variant and 5 (14.7%) the minor NAB2ex6-STAT6ex16/17. NAB2ex4-STAT6ex2 was significantly associated with older age (P = 0.01) and pleuropulmonary tumors (P = 0.025). After a median follow-up of 33.9 (range, 0.3-174.6) months, adverse outcomes occurred in one atypical and five malignant SFTs, including two local relapses, one intrapulmonary metastasis, and three extrathoracic metastases. Inferior disease-free survival was univariately associated with atypical/malignant histology (P = 0.001) and a mitosis >4/10 HPFs (P = 0.0012) but was unrelated to fusion variants. In conclusion, the majority of intrathoracic SFTs exhibited STAT6 nuclear staining, and NAB2ex4-STAT6ex2/3 was the predominant fusion type. However, clinical aggressiveness is associated with atypical/malignant histology primarily contributed by increased mitosis but was unrelated to the NAB2-STAT6 fusion variants.

NAB2-STAT6 fusion types account for clinicopathological variations in solitary fibrous tumors.

Solitary fibrous tumor (SFT) is characterized by the inv12(q13q13)-derived NAB2-STAT6 fusion, which exhibits variable breakpoints and drives STAT6 nuclear expression. The implications of NAB2-STAT6 fusion variants in pathological features and clinical behavior remain to be characterized in a large cohort of SFTs. We investigated the clinicopathological correlates of this genetic hallmark and analyzed STAT6 immunoexpression in 28 intrathoracic, 37 extrathoracic, and 23 meningeal SFTs. These 88 tumors were designated as histologically nonmalignant in 75 cases and malignant in 13, including 1 dedifferentiated SFT. Eighty cases had formalin-fixed and/or fresh samples to extract assessable RNAs for RT-PCR assay, which revealed NAB2-STAT6 fusion variants comprising 12 types of junction breakpoints in 73 fusion-positive cases, with 65 (89%) falling into 3 major types. The predominant NAB2ex4-STAT6ex2 (n=33) showed constant breakpoints at the ends of involved exons, whereas the NAB2ex6-STAT6ex16 (n=16) and NAB2ex6-STAT6ex17 (n=16) might exhibit variable breakpoints and incorporate NAB2 or STAT6 intronic sequence. Including 73 fusion-positive and 7 CD34-negative SFTs, STAT6 distinctively labeled 87 (99%) SFTs in nuclei, exhibited diffuse reactivity in 73, but did not decorate 98 mimics tested. In seven fusion-negative cases, 6 were STAT6-positive, suggesting rare fusion variants not covered by RT-PCR assay. Regardless of histological subtypes, intrathoracic SFTs affected older patients (P=0.035) and tended to be larger in size (P=0.073). Compared with other variants, NAB2ex4-STAT6ex2/4 fusions were significantly predominant in the SFTs characterised by intrathoracic location (P<0.001), older age (P=0.005), decreased mitoses (P=0.0028), and multifocal or diffuse STAT6 staining (P=0.013), but not found to correlate with disease-free survival. Conclusively, STAT6 nuclear expression was distinctive in the vast majority of SFTs, including all fusion-positive tumors, and exploitable as a robust diagnostics of CD34-negative cases. Despite the associations of NAB2-STAT6 fusion variants with several clincopathological factors, their prognostic relevance should be further validated in large-scale prospective studies of SFTs.

Thromboprophylaxis after minimally invasive total knee arthroplasty: a comparison of rivaroxaban and enoxaparin.

BACKGROUND: Total knee arthroplasty (TKA) carries a substantial rate of venous thromboembolism (VTE). The blood-saving of effect of tranexamic acid (TEA) in TKA using enoxaparin for thromboprophylaxis has been well known. However, the routine use of chemoprophylaxis in TKA remains controversial because of postoperative bleeding complications. Therefore, the purpose of this study was to retrospectively compare the incidence of VTE, and postoperative blood loss and wound-related complications in minimally invasive (MIS)-TKA patients who received rivaroxaban or enoxaparin prophylaxis. METHODS: A total of 113 patients who underwent primary unilateral MIS-TKA between 2009 and 2012 were studied. Of these, 61 patients (study group) received rivaroxaban prophylaxis between 2011 and 2012 and a control group of 52 patients received enoxaparin prophylaxis between 2009 and 2010. All patients received one intraoperative injection of TEA (10 mg/kg). We compared the changes in hemoglobin (Hb) level, postoperative drainage amount, total blood loss, transfusion rate, and incidence of postoperative wound complications and VTE between the two groups. RESULTS: No differences in postoperative Hb levels, blood drainage amount, total blood loss, and transfusion rate were observed between the two groups. No deep-vein thrombosis of the leg or pulmonary embolism was noted in both groups. There were no major wound complications including hematoma and infection requiring surgical intervention for open irrigation or debridement. CONCLUSIONS: Our retrospective study demonstrated a low rate of VTE in MIS-TKA patients who received rivaroxaban or enoxaparin when TEA was used for bleeding prophylaxis. No increased perioperative bleeding or postoperative wound-related complications were observed in the rivaroxaban group compared with the enoxaparin group.