Radiographic evaluation of robot-assisted versus manual total hip arthroplasty: a multicenter randomized controlled trial.

BACKGROUND: The effectiveness of robot-assisted surgery remains contentious due to the lack of high-quality randomized controlled trials (RCTs) to elevate the level of evidence. We aimed to evaluate the postoperative radiographic outcomes of robot-assisted (RAS-THA) versus manual (M-THA) total hip arthroplasty. METHODS: This multicenter RCT was performed from March 1, 2021 to December 1, 2021. Patients were randomly assigned to routine M-THA or to RAS-THA that used the TRex-RS orthopedic joint surgical navigation system. The primary outcome was to compare the acetabular component orientation, femoral stem alignment, femoral canal fill ratio, and leg length discrepancy between RAS-THA and M-THA using postoperative radiography. Subgroup analyses of the two groups stratified by surgical approach, gender, and BMI were also conducted. RESULTS: Seventy-three participants were randomly allocated to the RAS-THA group, while seventy-two participants were assigned to the M-THA group. Compared to the M-THA group, the RAS-THA group exhibited less variability in the preoperative planning of the vertical center of rotation (VCOR; P < 0.001), demonstrated a significant advantage in femoral stem alignment (P = 0.004), and showed pronounced decreases in inequality and in the variability in leg length discrepancy (P < 0.001). There was no significant difference in the Lewinnek safe-zone ratio (P = 0.081) and the femoral canal fill ratio (P > 0.05) between the two groups. Further subgroup analysis also showed that the RAS-THA group had fewer horizontal center of rotation (HCOR) and leg length differences when stratified by surgical approach, gender, and overweight status. CONCLUSION: This RCT found that, regardless of the surgical approach, gender, or body mass index, RAS-THA can effectively improve the postoperative VCOR and significantly reduce the variability of leg length difference. RAS-THA should be considered an effective method to enhance surgical precision by achieving less variability in challenging patients with leg length discrepancies. TRIAL REGISTRATION: ChiCTR2100044124.

Primary pulmonary meningioma and minute pulmonary meningothelial-like nodules: Rare pulmonary nodular lesions requiring more awareness in clinical practice.

In this editorial, we comment on an article by Ruan et al published in a recent issue of the World Journal of Clinical Case. Pulmonary meningothelial proliferative lesions, including primary pulmonary meningiomas, minute pulmonary meningothelial-like nodules, and metastatic pulmonary meningiomas are rare pulmonary lesions. These lesions are difficult to differentiate from lung cancers based on clinical and imaging manifestations. Herein, we briefly introduce the clinical, imaging, and pathological characteristics of these lesions and discuss their pathogenesis to strengthen the current understanding of pulmonary meningothelial proliferative lesions in clinical diagnosis and therapy.

Multi-Physics Modeling of Melting-Solidification Characteristics in Laser Powder Bed Fusion Process of 316L Stainless Steel.

In the laser powder bed fusion process, the melting-solidification characteristics of 316L stainless steel have a great effect on the workpiece quality. In this paper, a multi-physics model was constructed using the finite volume method (FVM) to simulate the melting-solidification process of a 316L powder bed via laser powder bed fusion. In this physical model, the phase change process, the influence of temperature gradient on surface tension of molten pool, and the influence of recoil pressure caused by the metal vapor on molten pool surface were considered. Using this model, the effects of laser scanning speed, hatch space, and laser power on temperature distribution, keyhole depth, and workpiece quality were studied. This study can be used to guide the optimization of process parameters, which is beneficial to the improvement of workpiece quality.

Improved radiographic outcomes and decreased complications rate on the femoral side can be achieved by a novel designed whole-process robotic assisted hip system for total hip arthroplasty: a prospective randomized controlled trial.

Postoperative complications due to inaccurate prosthesis positioning are the main causes of early revision. The aim of this study was to (1) determine whether novel designed whole-process robotic assisted hip system allowed better radiographic outcomes and lower complications risk on the femoral side particularly stem subsidence compared to conventional THA, and to (2) identify the comparison of early clinical outcomes. 72 patients were initially enrolled and randomly divided into 2 groups. Finally, only 65 patients (31 RA-THAs, 34 C-THAs) were analyzed who had full 18-month follow-up data. Radiographic follow-up was performed at immediate and 6-month postoperatively, while clinical follow-up at 18-month postoperatively. Stem-related radiographic outcomes, femoral side complications and clinical scores were compared. The robotic arm allowed better radiographic outcomes of the femoral side, including a higher canal fill ratio (CFR) at B1 (P = 0.040), more neutral stem alignment (P = 0.029), lower subsidence (P = 0.023) and lower leg length discrepancy (LLD) (P = 0.010). In addition, low CFR at B1 (P = 0.001) was found the risk factor for subsidence. However, early clinical outcomes were consistent between both groups. The novel designed whole-process robotic assisted hip system covers both femoral and acetabular side operations. It allows accurate and safe manipulation of femoral side, including better stem-related radiographic outcomes and lower risk of subsidence and LLD. However, no advantage of robotic system in early clinical score was identified. Clinical trial registration number: ChiCTR2100044124.

A new designed full process coverage robot-assisted total hip arthroplasty: a multicentre randomized clinical trial.

OBJECTIVE: To compare the effect of a new complete robot-assisted total hip arthroplasty (RA-THA) with that of the manual total hip arthroplasty (MTHA) and to verify the accuracy and safety of the former. METHODS: Overall, 148 patients were enroled from 3 March 2021 to 28 December 2021 in this study and classified into RA-THA ( n =74 patients) and MTHA ( n =74 patients) groups. The sex, age, operative side, BMI, diagnosis, other basic information, operative time, acetabular prosthesis anteversion and inclination, femoral prosthesis anteversion and angulation, femoral prosthesis filling rate, leg length discrepancy (LLD), Harris hip score, and visual analogue scale (VAS) score of the two groups were compared. RESULTS: No significant differences were observed in the two groups regarding sex, age, operative side, BMI, diagnosis, Harris hip score, VAS score, acetabular inclination, acetabular prosthesis anteversion, femoral prosthesis anteversion, combined anteversion, and femoral prosthesis filling rate ( P >0.05). The operative time was significantly longer in the RA-THA group than in the MTHA group (106.71±25.22 min vs. 79.42±16.16 min; t=7.30, P <0.05). The femoral angulation (1.78°±0.64°) and LLD (2.87±1.55 mm) in the RA-THA group were significantly lesser than those in the MTHA group (2.22°±1.11° and 5.81±6.27 mm, respectively; t=-2.95 and t=-3.88, P <0.05). CONCLUSION: The complete RA-THA has some advantages over the traditional procedure in restoring the lower limb length and controlling the femoral prosthesis angulation. Thus, this study verifies the accuracy and safety of the robot-assisted system.

Suppression of MALAT1 promotes human synovial mesenchymal stem cells enhance chondrogenic differentiation and prevent osteoarthritis of the knee in a rat model via regulating miR-212-5p/MyD88 axis.

Osteoarthritis (OA) is one of the most common diseases of the skeleton. Long non-coding RNAs (lncRNAs) are emerging as key players in OA pathogenesis. This work sets out to determine the function of lncRNA MALAT1 in OA and the mechanisms by which it does so. Mesenchymal stem cells isolated from the human synovial membrane are called hSMSCs. The hSMSCs' surface markers were studied using flow cytometry. To determine whether or not hSMSC might differentiate, researchers used a number of different culture settings and labeling techniques. The expression levels of associated genes and proteins were determined using quantitative real-time polymerase chain reaction (RT-qPCR), western blotting (WB), and immunostaining. A dual luciferase reporter experiment and RNA immunoprecipitation (RIP) test demonstrated the direct association between miR-212-5p and MALAT1 or MyD88. MALAT1 was downregulated during the chondrogenic differentiation of hSMSCs, and underexpression of MALAT1 promotes chondrogenesis in hSMSCs. Using dual luciferase reporter and RIP assays facilitated the identification of MALAT1 as a competitive endogenous RNA (ceRNA) that sequesters miR-212-5p. Additionally, the expression of MYD88 was regulated by MALAT1 through direct binding with miR-212-5p. Significantly, the effects of MALAT1 on the chondrogenic differentiation of hSMSCs were counteracted by miR-212-5p/MYD88. Furthermore, our in vivo investigation revealed that the inhibition of MALAT1 mitigated osteoarthritis progression in rat models. In conclusion, the promotion of chondrogenic differentiation in hSMSCs and the protective effect on cartilage tissue in OA can be achieved by suppressing MALAT1, which regulates the miR-212-5p/MyD88 axis.

Factors Associated with Re-Displacement after Nonsurgical Treatment of Distal Radius Fractures in Adults: A Retrospective Study.

OBJECTIVE: Closed reduction combined with external fixation is a frequently utilized approach for treating distal radial fractures in adults. Nonetheless, the potential for re-displacement following external fixation remains. Analyzing the factors influencing re-displacement after nonsurgical treatment of distal radial fractures in adults is vital for preventing re-displacement and making prognostic assessments. METHODS: A retrospective analysis was performed on 884 patients who underwent nonsurgical treatment for distal radius fractures in the reduction room of the Orthopedics and Traumatology Department of Integrated Traditional Chinese and Western Medicine at Tianjin Hospital, Tianjin, China, between July 2019 and December 2022. Patients were categorized into two groups, namely displaced and nondisplaced, based on radiographic outcomes. Factors affecting fracture re-displacement were examined, including sex, age, side, AO/OTA type, external fixation, and radiographic outcomes at pre-reduction and immediate reduction. Logistic regression analysis was employed to identify the risk factors for fracture re-displacement, and ROC curves were constructed. RESULTS: Among the 884 patients, 563 (63.69%) experienced re-displacement after fracture reduction. There were no statistically significant differences (p > 0.05) between the two groups in terms of gender, external fixation method, and palmar tilt angle at pre-reduction and immediate reduction, while significant differences (p < 0.05) were observed in age, side, AO/OTA type, and radial inclination, radial length, and radiographic outcomes of ulnar variance at pre-reduction and immediate reduction. Multifactorial logistic regression analysis revealed that age (odds ratio [OR] = 1.027, p < 0.001), AO/OTA type (OR = 2.327, p = 0.005), ulnar variance at pre-reduction (OR = 1.142, p = 0.048), and ulnar variance at immediate reduction (OR = 1.685, p < 0.001) were significant factors (p < 0.05) associated with re-displacement following nonoperative treatment of adult distal radius fractures. For patients aged ≥60 years, the amount of missing radiographic outcomes was positively correlated with age. The receiver operating characteristic curve demonstrated that age ≥65.5 years, ulnar variance >3.26 mm at pre-reduction, and ulnar variance >2.055 mm at immediate reduction were high-risk factors for fracture re-displacement. CONCLUSIONS: Nonsurgical treatment of distal radius fractures exhibits a higher rate of re-displacement. Age, AO/OTA type, pre-reduction, and immediate reduction ulnar variance are key factors predicting fracture re-displacement.

Elucidating the mechanism of IL-1ß-Mediated Piezo1 expression regulation of chondrocyte autophagy and apoptosis via the PI3K/AKT/mTOR signaling Pathway.

For the pathogenesis of osteoarthritis (OA), the classical view is that chondrocyte apoptosis is associated with and may cause age-related joint degeneration. Recent observations indicate that Piezo1, a mechanical stress channel expressed in articular cartilage, plays a crucial role in this process. We wanted to investigate whether other conditions activate the expression of Piezo1 in chondrocytes. Therefore, we simulated OA to investigate whether Piezo1 gene expression and channel function were affected by the inflammatory factor,interleukin-1ß, and the role of Piezo1 in the regulation of autophagy and apoptosis of chondrocytes. After the primary culture of human chondrocytes, the primary chondrocytes were treated with different concentrations of IL-1ß. It was found that IL-1ß upregulated the expression of Piezo1 in human chondrocytes. After Piezo1 activation, we analyzed the expression of autophagy and apoptosis of chondrocytes and investigated whether the downstream PI3K/AKT/mTOR pathway mediated the autophagy and apoptosis of chondrocytes. IL-1ß activates Piezo1 to inhibit chondrocyte autophagy and promote chondrocyte apoptosis partially, represented by up-regulation of related proteins c-caspase 3, Bax expression, and down-regulation of Bcl2, LC3, p62 expression. Piezo1-siRNA inverted this step partially. Inhibition of the PI3K/AKT/mTOR pathway reduces Piezo1 inhibition of chondrocyte autophagy and activation of chondrocyte apoptosis. Therefore, IL-1ß-mediated Piezo1 inhibition of chondrocyte autophagy and promotion of chondrocyte apoptosis partially through the PI3K/AKT/mTOR pathway is considered a novel pathogenesis of osteoarthritis.

Primary adenomatoid tumor of the adrenal gland: A case report and literature review.

RATIONALE: Adenomatoid tumors are rare benign tumors, mainly involving the reproductive tract, such as the epididymis in men and the uterus and fallopian tubes in women. However, a few cases can occur outside the reproductive tract. Herein, we report a rare case of a primary adenomatoid tumor of the adrenal gland. PATIENT CONCERNS: A 50-year-old man underwent ultrasound examination and was found to have a right adrenal mass without elevated blood pressure, weakness after fatigue, frequent nocturnal urination urgency, pain, or a history of hematuria. The patient's general health was normal. Computed tomography revealed a polycystic mixed-density lesion in the right adrenal region, approximately 7.3 × 4.5 cm in size. DIAGNOSES: Based on the clinical information, morphological features, and immunohistochemistry results, a pathological diagnosis of primary adenomatoid tumor of the adrenal gland was made. INTERVENTION: Excision of the right adrenal gland and tumor through the 11 ribs. OUTCOMES: The patient's postoperative course was uneventful. LESSONS: Preventing misdiagnosis adenomatoid tumors with other types of adrenal gland tumors or metastatic tumors is imperative. Morphological and immunohistochemical features can help diagnose primary adenomatoid tumors of the adrenal gland.

Accuracy and safety of a new robotic arm for both femoral and acetabular side in total hip arthroplasty: a cadaveric study.

BACKGROUND: To investigate the accuracy and safety of a newly constructed robotic arm which can cover the whole process of THA, we performed a series of robot-assisted total hip replacement on the cadaver. METHODS: Fifteen frozen cadaveric specimens (30 hips) were used for this study. In this investigation, united hip system and Longwell robotic-assisted system were used. The entire lower limb was CT scanned prior to surgery. The 3D model was produced based on CT data; the site of the prosthesis, including acetabular anteversion, inclination angle, and the position of femoral prosthesis, was planned. With the assistance of a robotic arm, the surgeon changed the parameters based on the preoperative plan and the actual condition during surgery, and completed the whole procedure. Following surgery, we measured the acetabular anteversion angle, acetabular inclination angle, femur anteversion angle, combined anteversion angle, stem angulation, and canal fill ratio. RESULTS: The parameters proved that the acetabular anteversion angle was 16.85 ± 3.00°, the acetabular inclination angle was 40.38 ± 5.37°, femur anteversion angle was 15.90 ± 9.01°, combined anteversion angle was 32.75 ± 9.03°, stem angulation was 1.84 ± 0.99°, and leg length discrepancy was 2.47 ± 1.43 mm. The canal fill ratio (CFR) of femoral prosthesis of osteotomy line in sagittal section is 99.72 ± 1.54% and in coronal section is 62.94 ± 8.91%; below osteotomy line 2.5 cm in sagittal section is 100.00% and in coronal section is 81.48 ± 12.94%; below osteotomy line 7.5 cm in sagittal section is 59.51 ± 12.94% and in coronal section is 89.79 ± 11.13%; femoral shaft isthmus in sagittal section is 56.41 ± 13.80% and in coronal section is 84.95 ± 15.17%. CONCLUSION: The accuracy and safety of this novel robotic arm are suitable for preparing both the acetabular and femoral sides, providing evidence for clinical trial.

Temperature sensitive nanogel-stabilized pickering emulsion of fluoroalkane for ultrasound guiding vascular embolization therapy.

Various X-ray imaging technologies like computed tomography (CT) and digital subtraction angiography (DSA) are widely used in transcatheter arterial embolization (TAE) therapy for treating hepatocellular cancer (HCC) patients. Although they display high-contrast imaging, they have a few disadvantages, such as complex operation and exposure to ionizing radiation. Thus, ultrasound (US) imaging plays an important role in medical diagnosis because of its advantages, like simple and fast operation, no ionizing radiation exposure, and accurate real-time imaging. Subsequently, Poly N-isopropylacrylamide-co-2,2,3,4,4,4-Hexafluorobutyl methacrylate (PNF) nanogels were synthesized for stabilizing TGFPE, the Pickering emulsions of 2H, 3H-decafluoropentane (HDFP). These emulsions displayed dual abilities of thermosensitive sol-gel transition and long-term US imaging in vitro. Thus, it was concluded that these emulsions could achieve vascular embolization and long-term US imaging in vivo as per the TAE animal model results. The emulsion droplets' flow and accumulation were visualized under the US imaging guidance. In summary, the Pickering emulsions have the potential to be used as US-guided embolization material for mediating TAE surgeries.

Artificial intelligence planning and 3D printing augmented modules in the treatment of a complicated hip joint revision: a case report.

Total hip revision with osseous defects can be very difficult. Artificial intelligence offers preoperative planning, real-time measurement, and intraoperative judgment, which can guide prothesis placement more accurately. Three-dimensional printed metel augment modules which are made according to the individualized osseous anatomy, can fit the osseous defects well and provide mechanical support. In this case, we used AI to plan the size and position of the acetabular cup and 3D-printed augmented modules in a complicated hip revision with an acetabular bone defects, which achieved stable fixation and relieved hip pain postoperatively.

Piezo1 transforms mechanical stress into pro senescence signals and promotes osteoarthritis severity.

Osteoarthritis (OA) is a prevalent disease among elderly people and is often characterized by chronic joint pain and dysfunction. Recently, growing evidence of chondrocyte senescence in the pathogenesis of OA has been found, and targeting senescence has started to be recognized as a therapeutic approach for OA. Piezo1, a mechanosensitive Ca2+ channel, has been reported to be harmful in sensing abnormal mechanical overloading and leading to chondrocyte apoptosis. However, whether Piezo1 can transform mechanical signals into senescence signals has rarely been reported. In this study, we found that severe OA cartilage expressed more Piezo1 and the senescence markers p16 and p21. 24 h of periodic mechanical stress induced chondrocyte senescence in vitro. In addition, we demonstrated the pivotal role of Piezo1 in OA chondrocyte senescence induced by mechanical stress. Piezo1 sensed mechanical stress and promoted chondrocyte senescence via its Ca2+ channel ability. Moreover, Piezo1 promoted SASP factors production under mechanical stress, particularly in IL-6 and IL-1ß. p38MAPK and NF-κB activation were two key pathways that responded to Piezo1 activation and promoted IL-6 and IL-1ß production, respectively. Collectively, our study revealed a connection between abnormal mechanical stress and chondrocyte senescence, which was mediated by Piezo1.

Inverse correlation between Alzheimer's disease and cancer from the perspective of hypoxia.

Sporadic Alzheimer's disease and cancer remain epidemiologically inversely related, and exploring the reverse pathogenesis is important for our understanding of both. Cognitive dysfunctions in Alzheimer's disease (AD) might result from the depletion of adaptive reserves in the brain. Energy storage in the brain is limited and is dynamically regulated by neurovascular and neurometabolic coupling. The research on neurodegenerative diseases has been dominated by the neurocentric view that neuronal defects cause the diseases. However, the proposal of the 2-hit vascular hypothesis in AD led us to focus on alterations in the vasculature, especially hypoperfusion. Chronic hypoxia is a feature shared by AD and cancer. It is interesting how contradicting chronic hypoxia's effects on both cancer and AD are. In this article, we discuss the potential links between the 2 diseases' etiology, from comparable upstream circumstances to diametrically opposed downstream effects. We suggest opposing potential mechanisms, including upregulation and downregulation of hypoxia-inducible factor-1α, the Warburg and reverse-Warburg effects, lactate-mediated intracellular acidic and alkaline conditions, and VDAC1-mediated apoptosis and antiapoptosis, and search for regulators that may be identified as the crossroads between cancer and AD.

An experimental study on the impact of prosthesis temperature on the biomechanical properties of bone cement fixation.

PURPOSE: To investigate the effect of the femoral component and tibial plateau component temperature on the strength of cement fixation during total knee arthroplasty (TKA). METHODS: Femoral prosthesis, tibial plateau prosthesis, and polypropylene mold base were used to simulate TKA for bone cement fixation. Pre-cooling or pre-warming of femoral and tibial plateau components at different temperatures (4 °C, 15 °C, 25 °C, 37 °C, 45 °C), followed by mixing and stirring of bone cement at laboratory room temperature (22 °C), were performed during research. The prosthesis and the base adhered together, and the bone cement was solidified for 24 h at a constant temperature of 37 °C to verify the hardness of the bone cement with a push-out test. RESULTS: The push-out force of the femoral prosthesis after fixation was higher than that of the tibial plateau prosthesis, and with the increase of the prosthesis temperature, the push-out force after fixation of the bone cement also increased linearly and the porosity of the prosthetic cement in the tibia and femur decreased as the temperature increased. CONCLUSION: Without changing the mixing temperature and solidification temperature, the fixation strength of the femoral prosthesis is higher than that of the tibial plateau prosthesis. Properly increasing the temperature of the prosthesis can increase the push-out force of the fixation strength.

The influence of prosthetic positioning and proximal femoral morphology on leg length discrepancy and early clinical outcomes of cementless total hip arthroplasty.

BACKGROUND: Leg length discrepancy (LLD) is a common complication of total hip arthroplasty (THA). However, the relationship between femoral prosthesis filling, proximal femoral morphology, and acetabular prosthesis positioning with postoperative LLD and clinical outcomes is unclear. The aims of this study were to investigate the influence of canal flare index (CFI), canal fill ratio (CFR), center of rotation (COR), and femoral offset (FO) on (1) postoperative LLD; and (2) clinical outcomes in the two stem designs with different coating distribution. METHODS: The study cohort included 161 patients who underwent primary cementless THA between January 2021 and March 2022 with either proximal coating or full coating stems. Multivariate logistic regression was used to assess the effect of CFI, CFR, COR, and FO on postoperative LLD, and linear regression to assess their effect on clinical outcomes. RESULTS: No statistical difference was found in clinical outcomes or postoperative LLD between the two groups. High CFI (p = 0.014), low ΔVCOR (p = 0.012), and Gender (p = 0.028) were found independent risk factors for LLD one day postoperative. High CFI was also an independent risk factor for postoperative subjectively perceived LLD (p = 0.013). CFR at the level of 2 cm below the LT (p = 0.017) was an independent risk factor for Harris Hip Score. CONCLUSIONS: Proximal femoral morphology and acetabular prosthesis positioning but not femoral prosthesis filling affected the LLD. High CFI was an independent risk factor for postoperative LLD and subjectively perceived LLD, and low ΔVCOR was also an independent risk factor for postoperative LLD. Women were susceptible to postoperative LLD.

Selective Construction of Molecular Borromean Rings and [2]Catenane Utilizing Ether Bipyridyl Ligands.

A series of Cp* Rh-based discrete architectures was constructed by selecting four ether bipyridyl ligands and three half-sandwich rhodium(III) bimetallic construction units, respectively. This study demonstrates a strategy for making the transition from a binuclear D-shaped ring to a tetranuclear [2]catenane by adjusting the length of bipyridyl ligands. In addition, changing the position on the naphthyl group of the bipyridyl ligand from 2,6- to 1,5-position substitution can realize the selective synthesis of [2]catenane and Borromean rings under similar conditions. The above-mentioned constructions have been determined via X-ray crystallographic analysis, detailed NMR techniques, electrospray ionization-time-of-flight/mass spectrometry analysis, and elemental analysis.

Primary acinic cell carcinoma of the trachea: A case report and literature review.

RATIONALE: Salivary gland-type acinic cell carcinoma (ACC) is a low-grade malignancy. Primary ACC of the trachea and lungs is rare; here, we describe 1 such case. The histological morphology of tracheal ACC was similar to that of its salivary gland-associated equivalent. Because of its rarity, it is easily misdiagnosed as another type of tracheal or lung tumor. Microscopic analysis of pathological features and immunohistochemistry help diagnose primary ACC of the trachea and lungs. PATIENT CONCERNS: A 33-year-old female complained of shortness of breath and hemoptysis for 2 years, and reported the symptoms to have aggravated over the last 4 months. The patient was admitted to our hospital for further treatment. Enhanced computed tomography revealed a soft tissue density nodule shadow in the trachea, which was approximately 1.3 × 1.2 cm in size. DIAGNOSES: Based on the clinical information, morphological features, and immunohistochemistry, the pathological diagnosis was primary ACC of the trachea. INTERVENTION: The tracheal lesion was resected with an electric snare, electrotomy, freezing, and an argon knife using a rigid bronchoscope. OUTCOMES: The patient's postoperative course was uneventful. LESSONS: It is important to prevent misdiagnosis of this type of tumor as another type of lung tumor. Morphological and immunohistochemical features can be useful in diagnosing primary ACC of the trachea and lungs.

Thymic lipofibroadenomas: Three case reports.

BACKGROUND: Thymic lipofibroadenomas are extremely rare. In this study, we investigated the clinicopathological characteristics of thymic lipofibroadenomas. CASE SUMMARY: This study included three patients with thymic lipofibroadenomas. We retrospectively analyzed the patient data to determine the clinicopathological characteristics of thymic lipofibroadenomas. The study included one man and two women [mean age, 43 (33-59) years]. All patients were non-smokers and presented with well-defined anterior mediastinal tumors. The cut surfaces of the tumors were solid, with a mixture of yellow and white areas. Microscopic evaluation of resected specimens showed scattered cord-like structures of epithelial cells embedded within abundant fibrotic and hyaline stroma admixed with variable quantities of adipose tissue. One patient showed hyperplastic thymic tissue in a part of the tumor. CONCLUSION: Thymic lipofibroadenomas are an extremely rare type of benign thymic tumor. Surgical removal of lipofibroadenomas is usually curative.