Primary cutaneous infections with non-tuberculous mycobacteria: a report of 6 cases.

BACKGROUND: The incidence of non-tuberculous mycobacterium infection has shown a gradual increasing trend in recent years, among which cutaneous manifestations as an important aspect. This study aimed to describe the clinical features and microbiological findings in 6 cases of primary cutaneous nontuberculous mycobacterium infection. METHODS: In this retrospective study from June 2021 to June 2022, the clinical data and microbiological results of six cases diagnosed with primary cutaneous non-tuberculous mycobacterium infection in department of dermatology, Hangzhou Third People's Hospital were analyzed. RESULTS: All six cases were primary cutaneous non-tuberculous mycobacterium infections, four of which had a history of trauma or exposure, and two had an underlying disease that could lead to compromised immunity. All patients presented with erythema nodular skin lesions, four on the upper or lower extremities, one on the face, and one on the right hip. The histopathological findings of five patients who underwent biopsy were granulomatous inflammatory changes with mixed infiltration. Laboratory cultures using tissue or tissue fluid were all successful, including four Mycobacterium marinum, one Mycobacterium abscessus, and one Mycobacterium avium. Metagenomics next-generation sequencing detected results consistent with culture colonies in only two cases. With the exception of case 4, all patients responded well to oral medication, with a course of treatment ranging from 4 months to 1 year, and the prognosis was good. CONCLUSIONS: The clinical features of primary cutaneous non-tuberculous mycobacterium infection are often lacking in specificity, and the identification of related strains is difficult for a variety of reasons. Although the results of metagenomics next-generation sequencing are useful for pathogen spectrum identification, its diagnostic value should be carefully reevaluated under certain circumstances. Patients with suspected triggers who do not respond well to conventional treatments should be suspected as atypical infection and potential immunosuppression. If diagnosed and treated promptly, the prognosis of primary cutaneous non-tuberculous mycobacterium infection is generally good.

Biochemical analysis of soft tissue infectious fluids and its diagnostic value in necrotizing soft tissue infections: a 5-year cohort study.

BACKGROUND: Necrotizing soft tissue infections (NSTI) are rapidly progressing and life-threatening conditions that require prompt diagnosis. However, differentiating NSTI from other non-necrotizing skin and soft tissue infections (SSTIs) remains challenging. We aimed to evaluate the diagnostic value of the biochemical analysis of soft tissue infectious fluid in distinguishing NSTIs from non-necrotizing SSTIs. METHODS: This cohort study prospectively enrolled adult patients between May 2023 and April 2024, and retrospectively included patients from April 2019 to April 2023. Patients with a clinical suspicion of NSTI in the limbs who underwent successful ultrasound-guided aspiration to obtain soft tissue infectious fluid for biochemical analysis were evaluated and classified into the NSTI and non-necrotizing SSTI groups based on their final discharge diagnosis. Common extravascular body fluid (EBF) criteria were applied. RESULTS: Of the 72 patients who met the inclusion criteria, 10 patients with abscesses identified via ultrasound-guided aspiration were excluded. Based on discharge diagnoses, 39 and 23 patients were classified into the NSTI and non-necrotizing SSTI groups, respectively. Biochemical analysis revealed significantly higher albumin, lactate, lactate dehydrogenase (LDH), and total protein levels in the NSTI group than in the non-necrotizing SSTI group, and the NSTI group had significantly lower glucose levels and pH in soft tissue fluids. In the biochemical analysis, LDH demonstrated outstanding discrimination (area under the curve (AUC) = 0.955; p < 0.001) among the biochemical markers. Albumin (AUC = 0.884; p < 0.001), lactate (AUC = 0.891; p < 0.001), and total protein (AUC = 0.883; p < 0.001) levels also showed excellent discrimination. Glucose level (AUC = 0.774; p < 0.001) and pH (AUC = 0.780; p < 0.001) showed acceptable discrimination. When the EBF criteria were evaluated, the total scores of Light's criteria (AUC = 0.925; p < 0.001), fluid-to-serum LDH ratio (AUC = 0.929; p < 0.001), and fluid-to-serum total protein ratio (AUC = 0.927; p < 0.001) demonstrated outstanding discrimination. CONCLUSION: Biochemical analysis and EBF criteria demonstrated diagnostic performances ranging from acceptable to outstanding for NSTI when analyzing soft tissue infectious fluid. These findings provide valuable diagnostic insights into the recognition of NSTI. Further research is required to validate these findings.

Soft tissue scavenging patterns of mice on human remains.

Rodent scavenging of human remains is repeatedly documented in literature. However, most of this documentation is based on single-case examples. While this information is valuable, it does not provide an in-depth understanding of scavenger behavior in a single environment. Mouse scavenging data, in particular, lack larger sample sizes and data representing the full duration of scavenging activity. In documented cases, mice scavenge primarily the hands, the feet, and the head without significant progression into the rest of the body. At the Forensic Investigation Research Station in Whitewater, Colorado, deer mice (Peromyscus maniculatus group) scavenged tissue from 11 human donors. Motion activated game cameras and regular field photography documented scavenging progression and deer mouse behavior. Deer mice generally showed a preference for skin and fat, rarely consuming enough muscle to expose bone. The most scavenged sections of the body were the limbs and deer mice generally ignored the hands, the feet, and the head, unlike previous documentation. In a few cases, deer mice consumed tissue on the limbs in a distinct trail pattern. Most of the scavenging began in spring. This sample greatly expands on the existing documentation of mice overall and contributes much needed data on the progression of scavenging. Scavengers can have a significant impact on a death scene, so detailed documentation of different scavengers in a variety of environments can prove useful in the investigation process.

Proximal and classic epithelioid sarcomas are distinct molecular entities defined by MYC/GATA3 and SOX17/endothelial markers, respectively.

Epithelioid sarcoma (ES) is a rare tumor hallmarked by the loss of INI1/SMARCB1 expression. Apart from this alteration, little is known about the biology of ES. Despite recent advances in treatment, the prognosis of ES remains unsatisfactory. To elucidate the molecular underpinnings of ES, and to identify diagnostic biomarkers and potential therapeutic vulnerabilities, we performed an integrated omics profiling (RNA sequencing and methylation array) of 24 primary, untreated ESs. Transcriptome and methylome analysis identified two distinct molecular clusters that essentially corresponded to the morphologic variants of ES, classic ES (C-ES) and the more aggressive proximal ES (P-ES). The P-ES group was characterized by hyperactivation of GATA3 and MYC pathways, with extensive epigenetic rewiring associated with EZH2 overexpression. Both DNA methylation and gene expression analysis indicated a striking similarity with the "MYC subgroup" of ATRT, another SMARCB1-deficient tumor, implying a shared molecular background and potential therapeutic vulnerabilities. Conversely, the C-ES group exhibited an endothelial-like molecular profile, with expression of vascular genes and elevated pro-angiogenic SOX17 signaling. Immunohistochemistry validated the overexpression of the chromatin regulators GATA3 (9/12 vs. 0/16) and EZH2 (7/7 vs. 2/6) in P-ESs, and of the vascular factors SOX17 (8/8 vs. 1/10) and N-cadherin (5/9 vs 0/10) in C-ESs. Therefore, these molecules emerge as potential diagnostic tools to fill the gap represented by the lack of ES subtype-specific biomarkers. In summary, our study shows that P-ES and C-ES represent distinct molecular entities defined by MYC/GATA3 and SOX17/endothelial molecular traits, respectively. Besides providing insights into the biology of ES, our study pinpoints subtype-specific biomarkers and potential therapeutic vulnerabilities.

The Radiographic Characteristics of Mandibular Wisdom Teeth That Can Cause Severe Deep Neck Infection.

PURPOSE: Mandibular wisdom teeth can occasionally cause infections, which can progress to severe deep neck infections (DNIs) including deep neck abscesses or necrotizing soft tissue infections, which are fatal. This study aimed to identify the radiographic characteristics of mandibular wisdom teeth that developed severe DNIs. METHODS: This study included patients who were admitted for the treatment of severe mandibular wisdom tooth infection between July 2012 and June 2024 at a single center. Patient characteristics, clinical data, and radiographic findings were analyzed and compared between the severe DNI group and mild DNI group including patients with cellulitis or superficial abscess. P < 0.05 was considered significant. RESULTS: Nineteen of 42 patients (45.2%) were included in the severe DNI group. The multivariate analysis showed that the highest odds ratio (OR) was for the presence of a radicular cyst (OR=17.7), followed by the presence of a dentigerous cyst (OR =14.5). The most common mandibular wisdom tooth with a dentigerous cyst in patients with severe DNIs was inverted according to Winter's classification and type IIIC in the Pell and Gregory classification. CONCLUSION: Radiographic characteristics associated with severe DNIs included the presence of radicular and dentigerous cysts in the mandibular wisdom teeth. Especially in dentigerous cysts, deeply impacted teeth should be taken attention.

Penetrating Femoral Trauma: A Report on Its Management and Outcome.

Penetrating trauma of the femur poses significant life-threatening risks due to potential complications, particularly involving the femoral structures such as the femoral artery, femoral vein, and femoral nerve. These injuries can lead to severe outcomes, especially when accompanied by soft tissue damage. Effective management requires a thorough understanding of the injury's nature, including the extent of soft tissue involvement and associated complications. This report presents a case of a 42-year-old male patient with a penetrating femoral injury through the anterior and posterior aspect of the lower limb without associated fracture, which highlights the importance of prompt surgical intervention and the use of flap reconstruction to address complications such as necrotic soft tissue.

The Efficacy of Low-Level Laser Therapy on the Healing of Oral Wounds: A Systematic Review.

Wound healing is an intricate process involving biological alterations in cellular integrity. Low-level laser therapy (LLLT) includes special features that speed up tissue regeneration and wound healing. The objective of this review is to examine the outcomes of photobiomodulation therapy in terms of healing. A search strategy was prepared using MeSH terms and Boolean operators. The initial search was limited to randomized controlled trials in the English language from January 2014 until January 2024. An electronic search of the National Library of Medicine (NLM catalog), Google Scholar, and Scopus was conducted using Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. The studies used LLLT of various wavelengths and parameters on oral wound healing. A total of 54 records were identified through database searching. In total, 14 studies were included according to the inclusion criteria. Ten studies examined the effects of LLLT in post-surgical hard and soft tissue healing in humans. Four animal studies observed the efficacy of photobiomodulation on the healing of bone tissue. All investigations found a substantial contrast between control and laser groups concerning wound epithelialization. When used as an adjunct or a substitute, LLLT has advantages in terms of pain and inflammation by boosting acetylcholine esterase synaptic activity, beta-endorphin synthesis, and serotonin production. By promoting the growth of osteoblasts and fibroblasts, LLLT can enhance the production of new bone at an early stage. Hence, further studies and meta-analyses are required for a better understanding of the mechanism and to confirm the efficacy with different parameters.

Isolated Pancreatic Metastasis in a Patient With Orbital Rhabdomyosarcoma: A Report of a Rare Case.

Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and adolescents and its occurrence in adults is extremely rare. There are three major subtypes of RMS of which alveolar RMS (ARMS) has the worst prognosis and tends to metastasize to unusual locations such as the pancreas. We present a case of a 19-year-old male with a rapidly enlarging right orbital mass, the imaging of which revealed it to be an infiltrative lesion with extension into the nasal cavity, ethmoid sinuses, and intracranial involvement. Histopathology confirmed the diagnosis of ARMS. A staging CT scan showed an enlarged and hypoenhancing pancreas; the histopathology test confirmed ARMS metastasis. It is important to consider pancreatic involvement in patients with ARMS, as it may be misinterpreted with other pathologies such as pancreatitis and pancreatic lymphoma. Metastasis to the pancreas can significantly alter the clinical approach and staging, underscoring the need for accurate diagnosis and staging in these patients.

Comparison of the efficacy of medial tarsal venous flaps and traditional venous/arterial free flaps in the reconstruction of hand soft tissue defects: A new type of physiological flap.

BACKGROUND: The treatment of hand soft tissue defects primarily relies on flap reconstruction. However, traditional venous/arterial free flaps have several disadvantages, including damage to the donor site, bruising, discoloration, blister formation, and even necrosis. These issues can significantly impact patient recovery and outcomes. Therefore, there is a need for alternative approaches that minimize these complications and improve overall patient care. OBJECTIVE: To compare the efficacy of medial tarsal venous flaps and traditional venous/arterial free flaps in the reconstruction of hand soft tissue defects, evaluating various clinical outcomes and patient recovery metrics. MATERIALS AND METHODS: We screened 30 suitable patients with hand soft tissue defects and randomly assigned them to three groups. Patients in each group were transplanted with either medial tarsal free venous flaps or traditional arterial/venous free flaps to achieve coverage and reconstruction of the soft tissue defects. The results were compared and analyzed using the following metrics: operation time, survival rate, complication rate, pain index, postoperative infection rate, and functional evaluations of both the donor and recipient areas. RESULTS: There was no significant difference in operation time between the medial tarsal free venous flaps and the traditional forearm free venous flaps. The operative time for both types of flaps was shorter than that of the traditional free fibular flap from the hallux. The survival rate of the medial tarsal free venous flaps was comparable to that of the fibular free arterial flaps from the great toes and significantly higher than that of the traditional forearm free venous flaps. The complication rate showed an inverse trend to the survival rate of the flaps. In terms of pain, the pain index for the medial tarsal free venous flaps was significantly lower than that of the fibular free arterial flaps from the hallux and comparable to that of the forearm free venous flaps. Regarding postoperative infection rates, the forearm free venous flap had the highest rate, while there was no significant difference between the medial tarsal free venous flaps and the fibular free arterial flaps from the great toes. The functional recovery of the medial tarsal free venous flaps was good in both the donor and recipient areas. There was no poor functional performance in the donor areas of the fibular free arterial flaps from the hallux or the recipient areas of the forearm free venous flaps. CONCLUSIONS: The medial tarsal free venous flaps effectively avoid the disadvantages of traditional venous and arterial free flaps, combining their advantages. These flaps offer shorter operative times, higher survival rates, and lower pain indices. They also provide excellent functional recovery in both donor and recipient areas. Thus, medial tarsal free venous flaps represent an ideal solution for reconstructing hand soft tissue defects.

Recent progress of poly(glycerol adipate)-based network materials toward tissue engineering applications.

Poly(glycerol adipate) (PGA) is one of the aliphatic polyesters of glycerol. The most studied biomedical application of poly(glycerol adipate) is the use of its nanoparticles as drug delivery carriers. The PGA prepolymer can be crosslinked to network materials. The biomedical application of PGA-based network materials has largely remained unexplored till recently. The PGA-based network materials, such as poly(glycerol sebacate) elastomers, can be used in soft tissue regeneration due to their mechanical properties. The modulus of elasticity of PGA elastomers is within the range of MPa, which corresponds to the mechanical properties of human soft tissues. This short review aims at briefly summarizing the possible applications of PGA-based elastomers in tissue engineering, as indicated in recent years in research publications.

Efficacy and Safety of Cell-Assisted Acellular Adipose Matrix Transfer for Volume Retention and Regeneration Compared to Hyaluronic Acid Filler Injection.

BACKGROUND: Cell-assisted acellular adipose matrix (AAM) transfer is a novel technique for soft tissue volume restoration, where AAM acts as a scaffold for tissue proliferation and promotes host cell migration, vascularization, and adipogenesis. This study aimed to evaluate the efficacy and safety of in vivo cell-assisted AAM transfer compared to hyaluronic acid (HA) filler injection. METHODS: Human adipose tissue was used to manufacture AAM, and murine adipose-derived stem cells (ASCs) were prepared. Nude mice were divided into four groups: AAM transfer (AT), ASC-assisted AAM transfer (CAT), HA filler injection (HI), and ASC-assisted HA filler injection (CHI). Eight weeks post-transfer, in vivo graft volume/weight, histology, and gene expression were analyzed to assess efficacy and safety. RESULTS: The AAM retained its three-dimensional scaffold structure without cellular components. AT/CAT showed lower volume retention than HA/CHA; however, CAT maintained a similar volume to HA. Histologically, adipogenesis and collagen formation were increased in AT/CAT compared to HA/CHA, with CAT showing the highest levels. CAT also demonstrated superior angiogenesis, adipogenesis, and gene expression (Vegf and Pparg), along with lower Il-6 expression, higher Il-10 expression, and reduced capsule formation, indicating better biocompatibility. CONCLUSIONS: Cell-assisted AAM transfer is a promising technique for volume retention and tissue regeneration, offering a safe and effective alternative to HA filler injections. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Radiomics model for predicting distant metastasis in soft tissue sarcoma of the extremities and trunk treated with surgery.

PURPOSE: The aim of this study was to develop a radiomics model based on magnetic resonance imaging (MRI) for predicting metastasis in soft tissue sarcomas (STSs) treated with surgery. METHODS/PATIENTS: MRI and clinical data of 73 patients with STSs of the extremities and trunk were obtained from TCIA database and Jiangsu Cancer Hospital as the training set, data of other 40 patients were retrospectively collected at our institution as the external validation set. Radiomics features were extracted from both intratumoral and peritumoral regions of fat-suppressed T2-weighted images (FS-T2WIs) of patients, and 3D ResNet10 was used to extract deep learning features. Recursive feature elimination (RFE) and least absolute shrinkage and selection operator (LASSO) algorithms were used for the selection of features. Based on 4 different sets of features, 5 machine learning algorithms were used to construct intratumor, peritumor, combined intratumor and peritumor radiomics models and deep learning radiomics (DLR) model. The area under the ROC curve (AUC) and Decision curve analysis (DCA) were used to evaluate the ability of models to predict metastasis. RESULTS AND CONCLUSIONS: Based on 20 selected features from the deep-learning and radiomics features set, the DLR model was able to predict metastasis in the validation dataset, with an AUC of 0.9770. The DCA and Hosmer-Lemeshow test revealed that the DLR model had good clinical benefit and consistency. By getting richer information from MRI, The DLR model is a noninvasive, low-cost method for predicting the risk of metastasis in STSs, and can help develop appropriate treatment programs.

Comprehensive management of degloving soft tissue injuries of the extremity: A 12-year retrospective study.

BACKGROUND: Degloving soft tissue injuries (DSTIs) of the extremities, which are often underestimated in terms of their severity, present significant challenges to reconstructive surgeons. We propose a comprehensive management protocol to standardize the reconstructive approach, aiming for successful treatment of these devastating injuries. METHODS: We retrospectively analyzed data from consecutive patients with extremity DSTIs over a 12-year period. Patients were categorized into three age groups (0-17, 18-65, and >65 years) to highlight the different treatment options based on age. Various surgical techniques were employed depending on the injury pattern. Treatment strategies for each patient were individualized based on age, underlying conditions, and injury type. Wound healing, complications, and functional outcomes were recorded. RESULTS: Of the hospitalized patients, 20 were lost to follow-up, and 105 were included in the analysis. The mean age at the time of injury was 40 ± 44.9 years, with a mean follow-up of 30.1 ± 12.7 months. Furthermore, 19 % of patients were aged 0-17 years, 61 % were aged 18-65 years, and 20 % were aged >65 years. Treatment plans were personalized based on injury characteristics, with numerous patients being treated with a combination of multiple surgical techniques. Older patients had significantly longer wound healing times and delayed return to activities of daily living compared to the other age groups. Overall, patients were generally satisfied with their outcomes. The total complication rate was 46.7 %, with 79.5 % being categorized as major complications. Each complication was addressed with a tailored treatment plan. CONCLUSION: The management of DSTIs should be individualized, taking into account the specific characteristics of each injury. Age and medical fitness play crucial roles in determining both the surgical approach and prognosis. An accurate initial evaluation and thorough debridement are essential for optimal outcomes.

Ex vivo SIM-AFM measurements reveal the spatial correlation of stiffness and molecular distributions in 3D living tissue.

Living tissues each exhibit a distinct stiffness, which provides cells with key environmental cues that regulate their behaviors. Despite this significance, our understanding of the spatiotemporal dynamics and the biological roles of stiffness in three-dimensional tissues is currently limited due to a lack of appropriate measurement techniques. To address this issue, we propose a new method combining upright structured illumination microscopy (USIM) and atomic force microscopy (AFM) to obtain precisely coordinated stiffness maps and biomolecular fluorescence images of thick living tissue slices. Using mouse embryonic and adult skin as a representative tissue with mechanically heterogeneous structures inside, we validate the measurement principle of USIM-AFM. Live measurement of tissue stiffness distributions revealed the highly heterogeneous mechanical nature of skin, including nucleated/enucleated epithelium, mesenchyme, and hair follicle, as well as the role of collagens in maintaining its integrity. Furthermore, quantitative analysis comparing stiffness distributions in live tissue samples with those in preserved tissues, including formalin-fixed and cryopreserved tissue samples, unveiled the distinct impacts of preservation processes on tissue stiffness patterns. This series of experiments highlights the importance of live mechanical testing of tissue-scale samples to accurately capture the true spatiotemporal variations in mechanical properties. Our USIM-AFM technique provides a new methodology to reveal the dynamic nature of tissue stiffness and its correlation with biomolecular distributions in live tissues and thus could serve as a technical basis for exploring tissue-scale mechanobiology. STATEMENT OF SIGNIFICANCE: Stiffness, a simple mechanical parameter, has drawn attention in understanding the mechanobiological principles underlying the homeostasis and pathology of living tissues. To explore tissue-scale mechanobiology, we propose a technique integrating an upright structured illumination microscope and an atomic force microscope. This technique enables live measurements of stiffness distribution and fluorescent observation of thick living tissue slices. Experiments revealed the highly heterogeneous mechanical nature of mouse embryonic and adult skin in three dimensions and the previously unnoticed influences of preservation techniques on the mechanical properties of tissue at microscopic resolution. This study provides a new technical platform for live stiffness measurement and biomolecular observation of tissue-scale samples with micron-scale resolution, thus contributing to future studies of tissue- and organ-scale mechanobiology.

Unusual manifestation of synovial sarcoma: A rare case report with elevated beta HCG level.

Synovial sarcoma is a rare type of soft tissue sarcoma that typically arises in the lower extremities and rarely in the upper extremities. Here, we present an unusual case of a middle-aged man who complained of dyspnea, dry cough, and chest pain and was found to have a mass-like lesion on the ulnar side of his left wrist during physical examination. The patient also exhibited gynecomastia and had elevated ß-human chorionic gonadotropin (ßHCG) levels. Subsequent imaging and histopathological analysis of the wrist mass confirmed the diagnosis of synovial sarcoma with disseminated lung metastasis. This article aims to provide a comprehensive overview of the clinical and pathological characteristics of synovial sarcoma, highlight the importance of considering synovial sarcoma as a differential diagnosis in patients with abnormal hormonal assays, and emphasize the need for clinicians to be vigilant about any pathologic lesions existing on the upper extremity to avoid late diagnosis and the development of advanced cancerous diseases.

An anatomical study of thenar and hypothenar soft tissue thickness in men and women.

We hypothesized that reduced thenar soft tissue thickness may be a risk factor for distal radial fractures. We assessed MRI scans of the wrist in 78 adults. The 51 men had significantly higher palmar soft tissue thickness compared to the 27 women, even after adjusting for hand size.Level of evidence: IV.

A rare case report of tissue infection caused by Pantoea piersonii (basionym Kalamiella piersonii).

In 2019, Pantoea piersonii was initially isolated from the interior surfaces of the International Space Station. This microorganism is a species within the genus Pantoea in the family Erwiniaceae, belonging to the order Enterobacterales. Recent literature has documented four cases of its isolation. Despite initial predictions suggesting the non-pathogenicity of P. piersonii strains, evidence from observed cases indicates potential pathogenicity. According to documented evidence in the literature, this microorganism is capable of causing severe and life-threatening conditions, including sepsis. Traditional tests, as well as automated systems, may fail to provide complete differentiation due to these similarities. While MALDI-TOF MS is a valuable tool for identification in clinical diagnostic microbiology, sequencing may be necessary for precise identification. To determine the antibiotic susceptibility profile, various methods can be utilized, including minimum inhibitory concentration determination, disk diffusion testing (Kirby-Bauer test), genotypic resistance assays (PCR and sequencing), and automated systems. The literature reports a limited number of cases associating P. piersonii with human infection. This study contributes to this body of knowledge by reporting a novel case in which P. piersonii was isolated from a tissue sample for the first time. In this case report, the patient achieved recovery following the administration of appropriate antibiotic treatment based on the diagnosis. It underscores the need for precise identification and understanding of its pathogenicity.

Dedifferentiated liposarcoma of the extremities: a Korean multi-center study of 107 cases.

BACKGROUND: Dedifferentiated liposarcoma of the extremities (DDL-E) is rare in comparison to that of the retroperitoneum. Its clinical features and surgical principle for resection margins at the dedifferentiated and the well-differentiated components are yet to be elucidated. METHODS: This retrospective multi-center study examined patients diagnosed with DDL-E from August 2004 to May 2023 at 5 sarcoma centers. Clinical features, oncologic outcomes, and prognostic factors were analyzed. RESULTS: A total of 107 patients were reviewed. The 5-year local recurrence free survival (LRFS), metastasis-free survival (MFS) and disease specific survival (DSS) were 84.7%, 78.6%, and 87.8%, respectively. Other primary malignancies and extrapulmonary metastasis were observed in 27 and 4 patients, respectively. The independent risk factor for local recurrence was R1/2 margin at the dedifferentiated component of the tumor. Metastasis was associated with tumor size in univariate analysis. The independent risk factor for DSS was tumor grade. Previous unplanned excision, de novo presentation, tumor depth, absence of the well-differentiated component, infiltrative border, R1/2 margin at the well-differentiated component were not associated with oncologic outcomes. CONCLUSIONS: This is the largest study examining DDL-E to-date. Localized DDL-E has low potential for metastasis and carries an excellent prognosis. Other primary malignancy and extrapulmonary metastasis are more frequent in DDL-E, thus close monitoring of other sites during follow-up is recommended. While wide resection margin is the standard surgical approach for DDL-E, further investigation into moderated wide resection margin at the well-differentiated component is warranted.

The Effect of Surgical Resection on Cancer-Specific Mortality in Pelvic Soft Tissue Sarcoma According to Histologic Subtype and Stage.

Background/Objectives: The impact of surgical resection versus non-resection on cancer-specific mortality (CSM) in soft tissue pelvic sarcoma remains largely unclear, particularly when considering histologic subtypes such as liposarcoma, leiomyosarcoma, and sarcoma NOS. The objective of the present study was to first report data regarding the association between surgical resection status and CSM in soft tissue pelvic sarcoma. Methods: Using data from the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2019, we identified 2491 patients diagnosed with pelvic soft tissue sarcoma. Cumulative incidence plots were used to illustrate CSM and other-cause mortality rates based on the histologic subtype and surgical resection status. Competing risk regression models were employed to assess whether surgical resection was an independent predictor of CSM in both non-metastatic and metastatic patients. Results: Among the 2491 patients with soft tissue pelvic sarcoma, liposarcoma was the most common subtype (41%), followed by leiomyosarcoma (39%) and sarcoma NOS (20%). Surgical resection rates were 92% for liposarcoma, 91% for leiomyosarcoma, and 58% for sarcoma NOS in non-metastatic patients, while for metastatic patients, the rates were 55%, 49%, and 23%, respectively. In non-metastatic patients who underwent surgical resection, five-year CSM rates by histologic subtype were 10% for liposarcoma, 32% for leiomyosarcoma, and 27% for sarcoma NOS. The multivariable competing risk regression analysis showed that surgical resection provided a protective effect across all histologic subtypes in non-metastatic patients (liposarcoma HR: 0.2, leiomyosarcoma HR: 0.5, sarcoma NOS HR: 0.4). In metastatic patients, surgical resection had a protective effect for those with leiomyosarcoma (HR: 0.6) but not for those with sarcoma NOS. An analysis for metastatic liposarcoma was not possible due to insufficient data. Conclusions: In non-metastatic soft tissue pelvic sarcoma, surgical resection may be linked to a reduction in CSM. However, in metastatic patients, this protective effect appears to be limited primarily to those with leiomyosarcoma.

Introduction of a New Mandibular Reconstruction Procedure Using a Sagittal Split: A Case Report.

Soft tissue excision and segmental mandibular resection for the treatment of benign or malignant oral tumors result in surgical defects of varying extents. These procedures are often followed by adjuvant chemotherapy and radiotherapy, which induce further adverse events with limited available treatment options. To reduce the morbidity and enhance the success rate of mandibular reconstruction, we developed a novel technique that combines a sagittal mandibular split and the use of a vascularized forearm flap graft. Here, we describe our experience with this procedure in an older male patient. The bridging bone segment was pedicled using the mylohyoid muscle and periosteum, and a reliable vascularized forearm graft was used to repair the soft tissue defect. The patient experienced a rapid recovery, and a two-year follow-up revealed that the bone and skin grafts tolerated radiotherapy well. We conclude that this technique is a viable alternative for patients with a bony gap around 4 cm or in whom a vascularized fibular flap graft is contraindicated.