The 2020 WHO Classification of Tumors of Soft Tissue: Selected Changes and New Entities

Postoperative outcome and clinical management of tumor-induced osteomalacia: a single-center retrospective cohort study on 117 patients

We reported a single-center retrospective cohort study on 117 patients of Tumor-induced osteomalacia (TIO) to summarize our experience with TIO over the past decade. The clinical characteristics, diagnosis, treatment and postoperative outcomes were analyzed. Together, our data demonstrate the characteristics and prognosis of TIO and unveil a possible TIO management process.

INTRODUCTION

TIO is a rare paraneoplastic syndrome that ultimately results in debilitating musculoskeletal deficits and regressive activity obstacles due to hypophosphatemia. The diagnosis and treatment of TIO are challenging owing to nonspecific symptoms, occult tumors and the lack of awareness. We aimed to summarize our experience with TIO over the past decade and to optimize its clinical management.

METHODS

A retrospective analysis was conducted of all patients with TIO admitted to our department and underwent surgical treatment at our hospital between 2012 and 2023. Clinical characteristics and postoperative outcomes were evaluated.

RESULTS

A total of 117 patients with typical clinical characteristics were enrolled, manifesting diffuse bone pain, decreased serum phosphate and elevated serum intact fibroblast growth factor-23 (iFGF23). All the patients were managed using a stepwise pathway detailing diagnosis, identification of the causative tumors, operations and postoperative surveillance. The causative tumors were equally located in bone and soft tissues, and the main sites were the lower extremities and pelvis (63.2%). 117 cases were caused by phosphaturic mesenchymal tumors (PMTs), which were usually small and benign, with a median volume of 1.45cm3 (IQR 0.70-4.17 cm3) and low Ki67 labeling indices (< 10%, 91.7%). After surgery, the serum P became normal within 7 days in 82.7% of the cured patients; serum iFGF23 decreased rapidly in one day and then gradually increased to normal with other laboratory indices and bone mineral density. The median follow-up period was 12 months (range, 1-144), during which 19 patients remained uncured. Among them, 5 patients experienced local recurrence and 2 suffered distant metastases. Younger age, bone-derived tumors and malignant tumors were risk factors for adverse outcomes. Tumors located in the femoral head, acetabulum, and spine showed a higher risk of obstinacy among bone-derived tumors.

CONCLUSION

TIO patients were able to benefit from the management including early recognition and diagnosis of the disease, identification and complete removal of the causative tumors, followed by regular postoperative surveillance. Of particular concern were patients with bone-derived tumors, who had high non-remission and recurrence rates.

CLINICAL TRIAL REGISTRATION

This study was registered with CHICTR.ORG.CN (ChiCTR2100042796).

Misdiagnosis of chordoma: A case report and a review of the literature

The present study aimed to investigate the clinicopathological features and diagnostic criteria for differentiating between chordoma and chordoid meningioma. A case of chordoma was retrospectively analyzed using clinical, radiographic, histological and immunohistochemical data, alongside a literature review. A 59-year-old male patient was admitted with headaches and dizziness persisting for 2 months without any obvious precipitating factors. The patient underwent two intracranial tumor resections between March 2022 and December 2023. The pathology report from the first surgery indicated that the tumor was composed of cords of epithelioid cells with vacuolated cytoplasm embedded in a basophilic stroma. Immunohistochemical analysis showed positivity for cytokeratin, vimentin, epithelial membrane antigen, synaptophysin, cytokeratin 8/18 and E-cadherin, with a Ki-67 proliferation index of 3%. Progesterone receptor, D2-40, glial fibrillary acidic protein, S100 and SOX10 staining were negative. Based on the pathology and immunohistochemical findings, the diagnosis was determined to be a chordoma-like meningioma (World Health Organization Grade 2). The pathology report from the second surgery revealed a tumor composed of cords and isolated epithelioid cells with intracytoplasmic vacuoles within a myxoid matrix. However, immunohistochemical analysis indicated positivity for Brachyury, leading to a diagnosis of chordoma. In conclusion, the histological morphology of chordoma is similar to that of chordoid meningioma and lacks clinical specificity. Immunohistochemical staining of tumor markers assists in both the diagnosis and differential diagnosis. Currently, treatment for chordoma and choroid mengioma primarily focuses on surgical resection, which is associated with high rates of relapse. The differential diagnosis predominantly influences the postoperative treatment strategy.

Pictorial essay on selected new, emerging, and reclassified entities in the 2020 WHO classification of soft tissue tumors

The 2020 WHO classification of soft tissue tumors includes major updates, incorporating new and emerging tumor entities, along with reclassified tumor types, supported by advances in immunohistochemistry and genetic data. This pictorial essay provides an overview of the selected new, "emerging," and reclassified soft tissue tumors, highlighting their imaging characteristics. Given the rarity of many of these entities, familiarity with their imaging features will aid in accurate diagnosis, ultimately contributing to improved patient care and management of these tumors.

A national survey of the current management of nonmalignant lipomatous tumours and a proposal for unified UK guidelines for practice

Although there exists clear guidance to determine which lipomatous lesions should be referred to a sarcoma multidisciplinary team (MDT) for discussion, subsequent guidelines for management advice are only focused on malignant lesions. This study aimed to address the management of benign and intermediate lipomatous lesions with reference to the available literature, precedent from 15 of the 17 UK sarcoma MDTs, and local experience. Fifteen mock cases were presented to each MDT to determine local management pathways. This revealed significant heterogeneity within the management of these benign and intermediate lipomatous lesions across the UK. After combining this data with the available evidence in the literature, we developed recommendations for management of these lesions with the aim to reduce national variability. We propose the first set of national management guidelines specific to benign lipomatous lesions, which stratifies resources according to lipomatous tumour type.

Radiomics and Deep Learning Model for Benign and Malignant Soft Tissue Tumors Differentiation of Extremities and Trunk

RATIONALE AND OBJECTIVES

To develop radiomics and deep learning models for differentiating malignant and benign soft tissue tumors (STTs) preoperatively based on fat saturation T2-weighted imaging (FS-T2WI) of patients.

MATERIALS AND METHODS

Data of 115 patients with STTs of extremities and trunk were collected from our hospital as the training set, and data of other 70 patients were collected from another center as the external validation set. Outlined Regions of interest included the intratumor and the peritumor region extending outward by 5 mm, then the corresponding radiomics features were extracted respectively. Deep learning was performed using pretrained 3D ResNet algorithms, and deep learning features were extracted from the entire FS-T2WI of patients. Recursive feature elimination and least absolute shrinkage and selection operator were used to select the radiomics and deep learning features with predictive value. Five machine learning algorithms were applied to build radiomics models, the area under the ROC curve (AUC) in the validation set were used to evaluate the diagnostic performance, and decision curve analysis (DCA) was used to evaluate the clinical benefit of models.

RESULTS

Based on 20 selected deep learning and radiomics features, the deep learning radiomics (DLR) model had the best predictive performance in the validation set, with an AUC of 0.9410. DCA and calibration curves showed that the DLR model had better clinical net benefit and goodness of fit.

CONCLUSION

By extracting more features from FS-T2WI, the DLR model is a noninvasive, low-cost, and highly accurate preoperative differential diagnosis of benign and malignant STTs.

The role of molecular pathology in soft tissue tumor diagnosis: what the radiologist needs to know

For both general radiologists and those specializing in soft tissue sarcoma imaging, understanding the importance and basic concepts of molecular pathology is becoming increasingly relevant to current clinical practice. As molecular research identifies the most fundamental causes and markers of disease, diagnostic testing is increasingly focused on the cell nucleus and its genetic material. Identifying molecular abnormalities, such as mutations, deletions, and amplifications, has advanced our ability to diagnose genetic diseases, including a variety of cancers. Over the past two decades, molecular pathology has rapidly evolved, enhancing our understanding of sarcoma pathogenesis, diagnosis, and classification. This progress forms the foundation of the 2020 WHO classification of soft tissue and bone tumors. This article will highlight cases where molecular diagnostics are crucial for the definitive classification and diagnosis of select soft tissue tumors, with MRI correlation and key teaching points.

Deciphering the role of liquid-liquid phase separation in sarcoma: Implications for pathogenesis and treatment

Liquid-liquid phase separation (LLPS) is a significant reversible and dynamic process in organisms. Cells form droplets that are distinct from membrane-bound cell organelles by phase separation to keep biochemical processes in order. Nevertheless, the pathological state of LLPS contributes to the progression of a variety of tumor-related pathogenic issues. Sarcoma is one kind of highly malignant tumor characterized by aggressive metastatic potential and resistance to conventional therapeutic agents. Despite the significant clinical relevance, research on phase separation in sarcomas currently faces several major challenges. These include the limited availability of sarcoma samples, insufficient attention from the research community, and the complex genetic heterogeneity of sarcomas. Recently, emerging evidence have elaborated the specific effects and pathways of phase separation on different sarcoma subtypes, including the effect of sarcoma fusion proteins and other physicochemical factors on phase separation. This review aims to summarize the multiple roles of phase separation in sarcoma and novel molecular inhibitors that target phase separation. These insights will broaden the understanding of the mechanisms concerning sarcoma and offer new perspectives for future therapeutic strategies.

Differentiation of benign, intermediate, and malignant soft-tissue tumours by using multiple diffusion-weighted imaging models

AIM

The aim of this study was to determine whether intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) can differentiate benign, intermediate, and malignant soft-tissue tumours (STTs) of the extremities and trunk.

MATERIALS AND METHODS

We prospectively recruited 100 STT patients (32, 15, and 53 patients with benign, intermediate, and malignant tumours, respectively). The patients underwent IVIM and DKI, and the following parameters were measured: standard apparent diffusion coefficient (ADC), perfusion fraction (f), true diffusion coefficient (Dslow), pseudo-diffusion coefficient (Dfast), water diffusion heterogeneity index (α), distributed diffusion coefficient (DDC), mean diffusivity (MD), and mean kurtosis (MK). Statistical analyses were performed using receiver operating characteristic curves, the Kruskal-Wallis H test, and post hoc test with Bonferroni correction.

RESULTS

Standard ADC, Dslow, DDC, and MD values gradually decreased from benign to intermediate and malignant STTs. Intermediate STTs displayed a lower f value than benign tumours (P=0.029). The MK value was higher in malignant tumours than in intermediate and benign tumours (P=0.021 and <0.001, respectively). The DDC value best differentiated benign tumours from nonbenign (intermediate and malignant) tumours (area under the curve [AUC] = 0.884, 0853, and 0.892, respectively). The optimal MK cut-off value for differentiating intermediate and malignant tumours was 0.65 (sensitivity: 73.33%, specificity: 81.13%, accuracy: 79.41%).

CONCLUSION

IVIM and DKI parameters were helpful for differentiating benign, intermediate, and malignant STTs and can complement conventional MRI, with DDC and MK values showing high diagnostic efficacy.

Epiphyseal osteosarcoma with serial changes of pretreatment imaging findings: a case report

BACKGROUND

Osteosarcoma is not often at the forefront of differential diagnoses for epiphyseal bone tumors because of its rarity; however, more than half of individuals affected by these uncommon cases experience a delay in diagnosis. In such clinical situations, the decision to promptly perform a biopsy of an epiphyseal bone tumor-while considering a potential diagnosis of osteosarcoma -remains unclear, particularly in adolescents. We present herein a case of epiphyseal osteosarcoma in an adolescent, the diagnosis of which was made with minimal delay.

CASE PRESENTATION

A 17-year-old male athlete presented to a previous hospital with knee pain. Radiographs obtained at the initial visit revealed a sclerotic mass in the femoral epiphysis. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a 32-mm lesion adjacent to the remaining epiphyseal scar. When the patient was referred to our hospital 3 weeks later, X-rays showed a circular radiolucent shadow lesion, as well as an enlargement involving the scar on CT. MRI showed altered signal intensities in the cartilage region, with an increase in synovial fluid. These longitudinal changes indicated the need for an incisional biopsy with minimal delay, considering the possibility of malignancy, which resulted in a diagnosis of epiphyseal osteosarcoma. The patient received perioperative chemotherapy followed by a wide resection. The pathological examination of the resected sample validated the initial diagnosis. As of 1 year post-surgery, disease relapse had not been detected.

CONCLUSIONS

This case highlights the benefit of longitudinal imaging investigations, which assisted in making a crucial diagnosis with minimal delay and enabled timely initiation of treatment before further disease progression.

Clinical diagnosis and treatment of abdominal inflammatory myofibroblastic tumors

OBJECTIVE

This study aims to summarize the clinicopathological characteristics, treatment methods, and prognosis of these patients. The goal is to enhance our understanding of the disease and provide insights for the standardized diagnosis and treatment of abdominal inflammatory myofibroblastic tumors(IMT).

METHODS

This retrospective cohort study included clinical data of 26 patients with abdominal IMT admitted to the First Hospital of Jilin University between January 2015 and December 2023. The clinical manifestations, pathological features, treatment methods, and prognoses were analyzed.

RESULTS

Among 26 patients, 6 had hepatic IMT, 2 splenic IMT, and 1 abdominal wall IMT, all detected incidentally as painless masses during routine exams. Six patients with mesenteric IMT reported abdominal distension, pain, nausea, vomiting, and low-grade fever. Of five patients with gastric IMT, three had gastrointestinal bleeding, one had distension and fever, and one had dysphagia. Four small intestine cases included one asymptomatic and three with obstruction symptoms. The colon and rectal cases presented with intermittent hematochezia. Surgery was performed in 24 patients, and 2 with metastases received palliative therapy. During follow-up, five patients relapsed; three received palliative therapy, and two had surgery. At last follow-up, 20 patients were disease-free, 3 were living with tumors, and 3 had died.

CONCLUSIONS

Abdominal IMTs are rare, low-grade tumors with favorable prognoses. Pathological examination is essential for diagnosis, and surgery is the primary treatment. Adjuvant therapy depends on tumor location and risk factors. Close follow-up is necessary due to the potential for recurrence and metastasis.

Surgical resection of a rare biatrial giant sarcoma: a case report

Primary cardiac undifferentiated sarcoma is an exceptionally rare entity, marked by nonspecific symptoms that considerably challenge its diagnosis and treatment. Surgical resection generally serves as the primary treatment modality. This article describes the case of a 32-year-old female patient admitted to the hospital with symptoms of abdominal distension and pain. Subsequent echocardiography revealed a cardiac tumor that occupied almost the entire left and right atria. The tumor was surgically removed in an emergency procedure, and subsequent pathological examination confirmed an undifferentiated sarcoma. The patient was successfully discharged 17 days after surgery. She then completed six cycles of chemotherapy. A six-month follow-up showed no signs of tumor recurrence or metastasis.

Relative Tumor Density of Soft-Tissue Sarcoma in Korean Population: An Institutional Review

BACKGROUND

Comprehensive studies on the tumor burden of soft-tissue sarcoma (STS) by anatomical site are lacking in Asian populations.

OBJECTIVE

To investigate the anatomical distribution of STS via relative tumor density (RTD) in a Korean cohort.

METHODS

The RTDs of patients with STS at a single-institution from 2007-2022 were retrospectively analyzed. To describe the STS locations, the body was divided into 4 anatomical sites, and the RTD of each was calculated to the compare topographic tumor burden.

RESULTS

Fifty-nine cases in 58 individuals, 35 male (60.3%) and 23 female (39.7%), with a mean age of 56.5±20.4 were analyzed. Overall, the most frequent STS site was the lower extremity (LE, n=22, 37.3%), and the highest RTD was in the head and neck (H&N, 2.44; 95% confidence interval, 1.39-3.77). Dermatofibrosarcoma protuberans (DFSP), Kaposi's sarcoma (KS), and angiosarcoma (AS) accounted for 76.3% of all the cases. DFSP, KS, and AS showed significantly higher RTD on the trunk (2.55, p=0.025), LE (3.88, p<0.001), and H&N (7.42, p<0.001), respectively, than elsewhere.

CONCLUSION

Each STS displays topographic variability and produces different topographic tumor burdens by body site in an Asian population.

Systematic Review of Soft Tissue Sarcomas in Latin America

PURPOSE

Soft tissue sarcomas (STSs) are rare malignant neoplasms posing significant public health challenges globally, especially in Latin America with limited research resources. This systematic review provides an overview of the epidemiology, clinical characteristics, treatment, and outcomes of STSs in Latin America, emphasizing the impact of insufficient investment in research and health care infrastructure.

MATERIALS AND METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a systematic literature review of clinicopathologic characteristics of STSs in Latin American patients. Studies published between January 1986 and August 2024 were included. A comprehensive search across multiple databases yielded 502 papers, refined to 18 publications and three national records included in the study. A meta-analysis was done for survival evaluation.

RESULTS

Data from 2,931 patients with mean age 47 years were analyzed, and 340 patients had pretreatment biopsy. The most common sarcoma types were liposarcoma (23.2%) and synovial sarcoma (21.2%), with high-grade tumors (52%) predominating. Treatment primarily involved surgery (863 patients), often combined with radiotherapy (559 patients) and chemotherapy (307 patients). Five-year overall survival was 61%.

DISCUSSION

The findings highlight challenges in managing STSs in Latin America, including advanced disease at diagnosis and high-grade tumors. Survival rates correlate with local advanced disease reported by other countries. Barriers include limited access to specialized centers and inadequate use of preoperative biopsies. Improved diagnostic and treatment strategies and collaborations to enhance research and clinical practices are needed.

CONCLUSION

This review underscores critical gaps in STS management in Latin America. Increased investment in research, a cohesive network of specialized care centers, and a multidisciplinary approach are essential to improve outcomes and quality of life for patients in the region.

Case Report: a giant liposarcoma of the spermatic cord

Background

Liposarcoma of the spermatic cord is an extremely rare urological malignancy, with fewer than 300 cases reported in the literature worldwide, and it is often difficult to distinguish from inguinal hernias and epididymal cysts. Typically, it presents as an asymptomatic, slow-growing paratesticular mass.

Case presentation

The case described herein involves a 59-year-old man who presented to our hospital with a painless mass in the left scrotum. Physical examination revealed a fixed, firm mass in the left scrotum. Ultrasonography of the scrotum demonstrated an inhomogeneous echogenic mass measuring approximately 113 x 83 x 62 mm on the left side. Testicular MRI showed a mass in the left scrotum measuring approximately 67 x 56 x 98 mm, exhibiting isointence T1 mixed with high T2 signals. The patient then underwent surgery and pathology confirmed a liposarcoma of the spermatic cord. Currently no signs of tumor recurrence on follow-up.

Conclusions

Liposarcoma of the spermatic cord is an exceedingly rare condition, for which surgical intervention is the preferred treatment option. While there is no definitive evidence supporting the use of adjuvant radiotherapy following surgery, it remains necessary in cases where surgical margins are uncertain.

Prevalence of hematological malignancies in Africa: A systematic review and meta-analysis

Hematological malignancies are a class of neoplasms that include a variety of diverse diseases that all develop from and change into lymphatic and bone marrow cells. Hematological malignancies significantly contribute to illness and mortality in African nations. The prevalence of these malignancies has not been evaluated in this continent. The purpose of this systematic review and meta-analysis was to assess the pooled prevalence of hematological malignancies in Africa. From October to November 2023, the electronic databases PubMed, Google Scholar, Web of Science, Research Gate, Embase, and Scopus were extensively searched to identify pertinent research. The Newcastle‒Ottawa Quality Scale for cross-sectional studies was used to assess the quality of the included studies. The analysis tool used was STATA-14. To calculate the pooled prevalence of hematological malignancies, a random effects model was used. Heterogeneity was measured by using the I2 value. Subgroup analysis was conducted for country, age of study subjects, population type, study design, and publication year. We evaluated publication bias through the implementation of a funnel plot and Egger's test and conducted a sensitivity analysis. A total of 34 published articles including 43,099 study participants were included. The pooled prevalence of hematological malignancies was 27.30%. There was high heterogeneity, with an I2 value of 99.2%. Leukemia had the highest pooled prevalence (53.69%) among the hematological malignancy types, followed by lymphoma (38.36%). According to subgroup analysis conducted in African countries, Kenya had the highest pooled prevalence (44.69%). On the other hand, the lowest pooled prevalence reported in Nigeria (20.52%). Furthermore, the age-based subgroup analysis of the study participants revealed that children had a greater pooled prevalence of hematological malignancies than adults (60.92% vs. 17.02%), respectively. In African populations, the pooled prevalence of hematological malignancies was 27.30%. This suggests that there is a significant prevalence of hematological malignancy, necessitating regular monitoring and accurate diagnosis.Trial registration PROSPERO CRD42023427152.

Self-assembled patient-derived tumor-like cell clusters for personalized drug testing in diverse sarcomas

Several patient-derived tumor models have emerged recently. However, soft tissue sarcomas (STSs) present a challenge in developing preclinical drug-testing models due to their non-epithelial and complex nature. Here, we report a model termed patient-derived tumor-like cell clusters (PTCs) derived from STS patients. PTCs result from the self-assembly and proliferation of mesenchymal stem cells (MSCs), epithelial cells, and immune cells, faithfully recapitulating the morphology and function of the original tumors. Through standardized culture and drug-response assessment protocols, PTCs facilitate personalized drug testing, evaluating hundreds of therapies within two weeks. Notably, PTCs exhibit 100% accuracy in distinguishing between complete or partial response and disease progression. We demonstrate the utility of PTCs in guiding chemotherapy selection for a patient with relapse and metastases following conventional therapy, who exhibited a positive response after non-conventional therapy identified through PTC. These findings underscore the potential of PTCs for prospective use in clinical decision-making regarding therapy selection.

A Rare Chordoma-The Epiglottic chordoma

Chordomas are rare malignant bone tumors. Chordomas originate from notochordal elements. Chordomas have the phenotype of the embryonic notochord, characterized by the dual expression of cytokeratin and brachyury. Chordomas occur anywhere along the central axis. Rarely, chordomas occur in extra-axial structures. We could not find any reports on epiglottic chordoma. Here, we present a case of epiglottic chordoma to highlight this rare cause of laryngeal mass.

Total talectomy and reconstruction using unrestricted 3D printed prosthesis for pediatric talus hemangioendothelioma

Background

Epithelioid hemangioendothelioma (EHE) is an ultra-rare vascular sarcoma with an extremely low incidence and prevalence, particularly in children. We report the case of a 9-year-old girl diagnosed with EHE. There are limited reconstruction methods available following total talus resection for vascular endothelioma of the talus, and the use of a 3D-printed talus prosthesis in pediatric cases has not been previously documented.

Case presentation

A 9-year-old girl presented to our unit with swelling, pain, and limited mobility of the ankle for one month without an obvious cause. X-ray and CT imaging revealed osteolytic lesions in the talus, which was identified as a low-grade malignant tumor that had nearly completely invaded the talus and was surrounded by immature bone. The American Foot and Ankle Surgery Association (AOFAS) score was 75/100. We performed a total resection of the talus followed by unrestricted talus replacement. Three months post-operation, the child was able to walk unaided. Ankle function was assessed at 6 and 13 months post-surgery, with the AOFAS score improving from 75 to 91, indicating that her functional needs for daily life were largely met.

Conclusion

Following complete excision of the lesion, the immature bone surrounding the talus was successfully preserved using an unrestricted 3D-printed prosthesis during ankle reconstruction. Our patient demonstrated satisfactory ankle function during the 6-month follow-up. This method is both safe and stable, yielding promising results, particularly for juvenile patients.

Preoperative denosumab combined with microwave ablation for joint preservation in advanced giant cell tumor of bone: a retrospective study

BACKGROUND

Preoperative denosumab has been an essential part of the management of giant cell tumor of bone (GCTB) which enhanced subchondral bone integrity and facilitated joint preservation surgery. However, evidence suggests that denosumab-induced sclerotic changes may potentially increase the risk of postoperative recurrence. This study evaluates the efficacy of microwave ablation (MWA) as an adjuvant to intralesional curettage following denosumab treatment in advanced GCTB.

METHODS

A retrospective review was conducted on 54 patients with extremity GCTB treated with preoperative denosumab between 2019 and 2024. 33 patients underwent curettage, while 21 patients underwent combined microwave ablation with curettage. The recurrence rates and joint preservation rates were analyzed. Functional outcomes were assessed by the Musculoskeletal Tumor Society (MSTS) score.

RESULTS

Local recurrence occurred in 14 patients, including 3 in the MWA group and 11 in the curettage-only group. In the MWA group, all recurrences were managed with repeat curettage, whereas 6 patients in the curettage-only group required extensive resection. The joint preservation rate was significantly higher in the MWA group (100%) compared to the curettage-only group (81.8%). The local recurrence rate was lower in the MWA group (14.3%) than in the curettage-only group (33.3%), with two-year local recurrence-free survival rates of 95.2% and 68.2%, respectively; however, the difference was not statistically significant (P = 0.12). Functional outcomes were comparable, with a mean MSTS score of 24.9 ± 1.33.

CONCLUSION

The preoperative denosumab combined with adjuvant MWA offers an alternative approach to enhance joint preservation in advanced GCTB, emphasizing its potential as an effective adjuvant strategy. Further large-scale studies are warranted to validate these findings and refine treatment strategies.

ANKRD2 Knockdown as a Therapeutic Strategy in Osteosarcoma: Effects on Proliferation and Drug Response in U2OS and HOS Cells

Ankrd2, a mechanoresponsive protein primarily studied in muscle physiology, is emerging as a player in cancer progression. This study investigates the functional role of Ankrd2 in osteosarcoma cells, revealing its critical involvement in cell proliferation and response to chemotherapeutic drugs. We showed that Ankrd2 knockdown impairs the activation of PI3K/Akt and ERK1/2 pathways, reduces levels of cell cycle regulators including cyclin D1 and cyclin B, and counteracts the expression of nuclear lamin A and lamin B, disrupting nuclear morphology and DNA integrity. Strikingly, the loss of Ankrd2 enhances the sensitivity of osteosarcoma cells to doxorubicin and cisplatin, highlighting Ankrd2 potential as a therapeutic target to improve chemotherapeutic efficacy. Defining a novel mechanistic role for Ankrd2 in promoting tumor progression, we propose that Ankrd2 reduction could be exploited as an adjuvant strategy to enhance the efficacy of chemotherapy, offering new therapeutic opportunities for OS treatment.

The Impact of Surgical Margin Distance on Local Recurrence and Survival in Patients with Soft Tissue Sarcoma

Background and Objectives: The primary objective of surgeons treating bone and soft tissue sarcomas (STS) is to achieve optimal local tumor control, ensuring a tumor-free margin and preventing local recurrence. However, the impact of surgical resection margin status on extremity STSs remains an area that requires further exploration. Therefore, this study aims to investigate the effects of surgical resection margin status on both local recurrence and overall survival rates. Materials and Methods: One hundred and eighty-five patients who underwent surgical resection with a diagnosis of soft tissue sarcoma were studied. The study recorded patient demographics, tumor characteristics, surgical margin distance (in millimeters), and disease-related outcomes. Results: The minimum follow-up period was 24 months (24-168). The mean time to local recurrence after resection was 103.2 months (95% CI 91.73 to 114.64). The mean local recurrence-free survival was found to be 7.23 months in patients with positive surgical margins, 87.42 months in patients with ≤1 mm, and 139.80 months in patients with >1 mm (p < 0.001). Patients with surgical margins ≤1 mm were more likely to have local recurrence than patients with >1 mm (0.41 [0.21-0.81], p = 0.010). The mean overall survival was 106.72 months (95% CI 95.98 to 117.46). Positive surgical margins were associated with decreased overall survival (3.58 [1.46-8.80], p = 0.005). There was a statistically significant difference between the histologic grade in terms of local recurrence (4.50 [95% CI 2.57 to 7.88]; p < 0.001) and overall survival (3.12 [95% CI 1.52 to 6.41]; p = 0.002). Conclusions: Achieving a negative surgical margin distance of more than 1 mm appears to be correlated with a reduced risk of local recurrence. Positive surgical margins are a risk factor that detrimentally impacts overall patient survival. However, determining the appropriate margin distance for all patients poses a significant challenge.

Primary Pulmonary Liposarcoma: A Case Report

Primary liposarcoma of the lung is extremely rare. To date, only 24 cases have been reported in the English literature. Herein, we present a case of well-differentiated pulmonary liposarcoma that was misdiagnosed as teratoma on positron emission tomography/computed tomography (CT) and contrast-enhanced CT. Radical surgery with left superior lobectomy and mediastinal lymph node dissection were performed. The patient experienced recurrence and distant metastases 33 months after surgery. He was alive at the time of writing this report (36 months postoperatively). To our knowledge, this is the first case report of pulmonary well-differentiated liposarcoma.

Pain Accelerates, Swelling and Sensory Disturbances Delay Diagnosis in Mesenchymal Tumors

Sarcomas are rare mesenchymal tumors with significant heterogeneity, encompassing both bone and soft tissue neoplasms that can range from benign to malignant and from superficial to deep-seated lesions [...].

Prognostic significance of lymph node metastasis of soft tissue sarcoma of the extremities. National cancer institute experience

BACKGROUND AND OBJECTIVE

Lymph node metastasis (LNM) in soft tissue sarcoma (STS) of the extremities is relatively rare. We aimed to evaluate the prognosis and the survival of patients with LNM and correlate them to the pattern of metastasis.

METHODS

A retrospective study of patients diagnosed with STS of the extremities from 2015 to 2019.

RESULTS

111/1506 patients (7.4%) had LNM. Nodal metastasis was correlated significantly with old age, advanced tumor stages, high-grade tumors, presence of Lymphovascular invasion (LVI), and resection margins <  = 2 cm. Metachronous LNM was documented in 96 patients (86.5%) and synchronous LNM in 15 patients (13.5%). The 6-year overall survival (OS) was 36.3% for those with LNM and 52.9% for those without LNM. The 6-year disease-free survival (DFS) was 5.7% for those with LNM and 32.6% for those without LNM. Metachronus pattern of LNM showed a significantly poorer outcome regarding 6-year OS and DFS than the synchronous pattern.

CONCLUSIONS

LNM significantly negatively predicts OS and DFS in the extremities' STS. In particular, the metachronous pattern of LNM indicates a grave prognosis as these patients are supposed to harbor an occult LNM at presentation and were not subjected to lymphadenectomy at their initial primary treatment surgery. Therefore, seeking a valid noninvasive diagnostic tool such as sentinel lymph node biopsy to detect nodal metastasis is necessary.

MRI Characteristics for Distinguishing Solitary Fibrous Tumor From Desmoid Tumor

OBJECTIVE

To elucidate the magnetic resonance imaging (MRI) characteristics for distinguishing solitary fibrous tumors (SFTs) from desmoid tumors (DTs).

MATERIALS AND METHODS

A retrospective study of 66 consecutive patients with histopathologically proven SFT (n = 34; 13 males and 21 females; mean age, 52.0 ± 17.1 years) or DT (n = 32; 11 males and 21 females; mean age, 39.0 ± 21.3 years) was conducted. The two groups were quantitatively compared in terms of the size, signal intensity ratio (SIR), and apparent diffusion coefficient value. For qualitative analysis, the tumor location, boundary, shape, internal uniformity, predominant signal intensity, T1-weighted images (T1WI) characteristics (hyperintense area), T2-weighted images (T2WI) characteristics (hypointense area, marked hyperintense area, flow void, band sign, and yin-yang sign), and contrast-enhanced T1WI characteristics (unenhanced area and degree of enhancement) were compared between the two groups. Multiple stepwise logistic regression analyses were conducted to distinguish between the SFT and DT.

RESULTS

T1 (P = 0.010) and T2 (P = 0.026) SIRs were higher in SFTs than in DTs. Hyperintense areas on T1WI (P < 0.001), marked hyperintense areas on T2WI (P = 0.025), and flow void (P = 0.025) were more frequently noted in SFTs. On T1WI, the solid component predominantly revealed hyperintensity in SFTs and isointensity in DTs (P < 0.001). Indistinct tumor boundary (P < 0.001), hypointense area on T2WI (P < 0.001), and band sign (P < 0.001) were more frequently observed in DTs. Multiple stepwise logistic regression analysis revealed that the hyperintense area on T1WI (odds ratio favoring SFT, 12.80, P = 0.002) and band sign (odds ratio favoring DT, 0.03; P < 0.001) were independent predictors.

CONCLUSION

MRI characteristics can help distinguish SFT from DT. The presence of a hyperintense area relative to the skeletal muscle on T1WI in SFTs and the band sign on T2WI in DTs are important MRI features.

"From Drowning to Treading Water": Adolescents and Young Adults Living with Incurable and Indolent Metastatic Soft Tissue Sarcoma for More than Two Years

INTRODUCTION

Adolescent/young adult (AYA) patients with metastatic soft tissue sarcoma (STS) typically face a dismal prognosis. However, a subset of patients with incurable disease lives beyond two years. Due to the rarity of diagnoses and inherent heterogeneity within this population, a paucity of data exists regarding the experiences of AYAs with an indolent course (and how to best capture these experiences). With increasing biological insight and clinical experience, including the use of targeted or immune therapies, it is anticipated that more such patients will experience prolonged survival. Our pilot study aimed to describe the clinical characteristics and illness experiences of AYAs with incurable yet indolent metastatic STS who were living two years after their diagnoses. Our exploratory aim was to generate a conceptual framework that could subsequently be tested in a multi-center study with a larger cohort of patients.

MATERIALS AND METHODS

Patients with metastatic incurable STS, aged 15-39 years at diagnosis, and at least two years from diagnosis, were eligible. Patients were recruited over a two-year period at a quaternary children's hospital with a comprehensive AYA oncology program. Participants completed a demographic form and PROMIS short form questionnaires for seven domains and answered an open-ended question. Responses to open-ended questions were coded independently by two authors and utilized to generate themes. Clinical variables were collected from medical records.

RESULTS

Five patients completed questionnaires. Mean age was 29.4 years (18.5-39.8 years) at diagnosis and 34 years (23.2-45.7 years) at study. Three patients were female; two were male; four were White; and one was Black/African American. Diagnoses included ASPSCR1::TFE3 alveolar soft part sarcoma; WWTR1::CAMTA1 epithelioid hemangioendothelioma; INI-1 deficient epithelioid sarcoma; EWSR1::NR4A3 extra-skeletal myxoid chondrosarcoma; and low-grade ARHGAP23::FER spindle cell malignancy, a novel fusion-driven sarcoma. Mean time since diagnosis was 4.5 years (2.6-6 years), and mean treatment duration was 4.2 years (1.5-6 years). On average, patients received 4.8 lines (range 2-8 lines) of antineoplastic therapy. All patients received at least one targeted therapy or immune checkpoint inhibitor. Patients reported increased fatigue and anxiety and decreased physical function compared to the standardized US reference population. Themes emerging from qualitative responses included managing physical symptoms, navigating feelings of guilt and inadequacy, self-reflection generating gratitude, and changing illness experiences over time.

CONCLUSIONS

AYA patients living with incurable metastatic soft tissue sarcoma for more than two years were treated with multiple lines of antineoplastic therapy longitudinally. PROMIS data identified fatigue, anxiety, and decreased physical function within this population. Exploratory thematic analysis of qualitative responses generated concepts that could be further tested in an expanded cohort of patients.

Myogenesis gone awry: the role of developmental pathways in rhabdomyosarcoma

Rhabdomyosarcoma is a soft-tissue sarcoma that occurs most frequently in pediatric patients and has poor survival rates in patients with recurrent or metastatic disease. There are two major sub-types of RMS: fusion-positive (FP-RMS) and fusion-negative (FN-RMS); with FP-RMS typically containing chromosomal translocations between the PAX3/7-FOXO1 loci. Regardless of subtype, RMS resembles embryonic skeletal muscle as it expresses the myogenic regulatory factors (MRFs), MYOD1 and MYOG. During normal myogenesis, these developmental transcription factors (TFs) orchestrate the formation of terminally differentiated, striated, and multinucleated skeletal muscle. However, in RMS these TFs become dysregulated such that they enable the sustained properties of malignancy. In FP-RMS, the PAX3/7-FOXO1 chromosomal translocation results in restructured chromatin, altering the binding of many MRFs and driving an oncogenic state. In FN-RMS, re-expression of MRFs, as well as other myogenic TFs, blocks terminal differentiation and holds cells in a proliferative, stem-cell-like state. In this review, we delve into the myogenic transcriptional networks that are dysregulated in and contribute to RMS progression. Advances in understanding the mechanisms through which myogenesis becomes stalled in RMS will lead to new tumor-specific therapies that target these aberrantly expressed developmental transcriptional pathways.

Intriguing tumor, synovial sarcoma: hard to diagnose, harder to treat

BACKGROUND

Synovial sarcoma (SS) is classified as an aggressive high-grade soft tissue sarcoma that predominantly affects the extremities. Despite its prevalence in the extremities (up to 80%), diagnostic and treatment challenges persist. This study aims to address these challenges by providing a comprehensive analysis of SS in extremities, focusing on diagnostic accuracy and treatment outcomes. The central questions of this study are: What are the diagnostic and treatment challenges associated with SS? How do tumor volume and histologic subtype influence prognosis? What role do immunohistochemistry and genetic markers play in SS diagnosis and management?

HYPOTHESIS

We hypothesize that larger tumor volume and poor histologic differentiation are associated with worse survival outcomes in patients with SS.

PATIENTS AND METHODS

This retrospective study analyzed data from 63 patients diagnosed with SS between 2005 and 2020 at a single center. Patients with complete records of pathology, radiology, and surgery, and a minimum follow-up of 12 months were included. Tumor characteristics, treatment modalities, and follow-up data were reviewed.

RESULTS

he study included 63 patients and 65 tumors. The mean age was 38 ± 17 years. There were 31 females (49%) and 32 males (51%). SS predominantly affected the extremities (n = 63, 97%), especially the lower limbs (n = 49, 75%). Tumor volume, with a mean of 110 ± 176 cm³, was a significant factor, with tumors >30 cm³ associated with higher rates of metastasis (p = 0,006) and reduced survival (p = 0,027). Histologically, 25 (38%) were monophasic, 24 (37%) were biphasic, and 16 (25%) were poorly differentiated, with poorer survival linked to poorly differentiated subtypes. Immunohistochemistry showed high positivity rates for Bcl-2 (89%, 17/19), EMA (88%, 52/59), and TLE1 (87%, 13/15). SS18-SSX fusion gene detected in 73% of cases (8/11). Metastasis occurred in 27 (42%) patients and recurrence in 24 (37%). 15 (23%) patients died from the disease.

DISCUSSION

Accurate diagnosis of SS is crucial for effective management. Clinicians should be aware of negative predictive factors, including tumor volume >30 cm³ and poor histologic differentiation, when making treatment decisions. The study highlights the importance of extended follow-up due to the risk of late recurrence.

LEVEL OF EVIDENCE

IV.

Identification and validation of soft tissue sarcoma-specific transcriptomic model for predicting radioresistance

PURPOSE

We aimed to identify the transcriptomic signatures of soft tissue sarcoma (STS) related to radioresistance and establish a model to predict radioresistance.

MATERIALS AND METHODS

Nine STS cell lines were cultured. Adenosine triphosphate-based viability was determined 5 days after irradiation with 8 Gy of X-rays in a single fraction. Radiosensitive and radioresistant groups were stratified according to the survival rates. Whole transcriptomic sequencing analysis was performed and differentially expressed genes (DEGs) were identified between the radiosensitive and radioresistant groups. For model generation, a cohort of 59 patients with sarcomas from The Cancer Genome Atlas (TCGA) was used. DEGs of the responder and non-responder groups according to the radiotherapy-best response were identified. The overlapping DEGs between those from TCGA data and the STS cell line were subjected to linear regression to develop a formula, namely the STS-specific radioresistance index (STS-RRI), and its performance was compared with that of the previously established radiosensitivity index (RSI).

RESULTS

We selected thirteen overlapping DEGs and established STS-RRI using seven of them: STS-RRI = 1.5185 × MYO16-0.01575 × MYH11 + 3.900375 × KCTD16 + 0.105375 × SYNPO2-0.777375 × MYPN-0.849875 × PCSK6-0.700125 × LTK + 39.4635. Delong's test revealed that the STS-RRI performed better at stratifying responder and non-responder in TCGA cohort than the RSI (p = .002). The progression-free survival curves of the TCGA cohort were significantly discriminated by STS-RRI (p = .013) but not by RSI (p = .241).

CONCLUSION

We developed the STS-RRI to predict the radioresistance of patients with STS in the TCGA dataset, showing a higher performance than RSI.

Primary renal BCOR::CCNB3 sarcoma in a female patient: case report

BCOR-rearranged sarcoma was classified by the World Health Organization in 2020 as a new subgroup of undifferentiated small round-cell sarcoma. It is known to occur very rarely in the kidney. This report presents the first case of a primary renal BCOR::CCNB3 sarcoma in a 22-year-old woman. An 8-cm cystic mass was identified in the left kidney by abdominal pelvic computed tomography. Histopathologic examination revealed the mass to be composed of small round to oval or spindle cells with fibrous septa and a delicate vascular network. A BCOR::CCNB3 fusion was detected by next-generation sequencing-based molecular testing. BCOR::CCNB3 sarcoma presents diagnostic difficulties, highlighting the importance of recognizing its histological features. Immunohistochemical markers are helpful for diagnosis, but genetic molecular testing is necessary for accurate diagnosis. These tumors have a very poor and aggressive prognosis, and an optimal therapeutic regimen has not yet been defined. Therefore, further studies are needed.

Metastatic multicentric epithelioid angiosarcoma of bone. A case report with pitfalls. Tumor seeding after percutaneous biopsy and hypercalcemia

Angiosarcomas are a type of malignant tumor of vascular origin. They represent <1% of all primary bone tumors. The multicentric or metastatic does not differ in its high aggressiveness and poor prognosis. A 72-year-old male with bone angiosarcoma initially located in proximal femur. After biopsy in a non-expert sarcoma center, he presented tumor involvement in the needle trajectory and multicentric/metastatic involvement at the sacro-coccygeal level. He associated tumoral-hypercalcemia and was referred to our sarcoma center. He was treated by tumoral resection and tumor prosthesis. In the follow-up he presented pulmonary metastasis and new implants, dying 2 months later. Multicentric or metastatic bone involvement in angiosarcomas has only theoretical relevance for their management. Biopsy should be performed in sarcoma centers due to the risk of dissemination. Although hypercalcemia in sarcomas is uncommon, we highlight its investigation.

Are all vulvar masses Bartholin cysts? A series of cases

INTRODUCTION

While vulvar masses are not prevalent in society, they are one of the reasons for complaints that arise during visits to gynecology outpatient clinics. An excision is typically necessary for both the purpose of diagnosing and treating the condition.

METHODS

We documented three exceptional instances with distinct histopathological diagnoses and varying presentations, as well as a consecutive series of five patients, including one Bartholin abscess and one labia major abscess.

RESULTS

During the compilation of this article, we intended to show that vulvar masses can manifest in various forms. It is important not to overlook pathologies other than Bartholin cysts and abscesses, which are commonly encountered reasons for admission to gynecology clinics. Additionally, it is crucial to always consider the possibility of malignant pathologies.

DISCUSSION

Clinicians' expertise and understanding of vulvar masses are comparatively inferior to their knowledge of other gynecological disorders. This case series presents the uncommon vulva masses that we found in our clinic.

DKI and 1H-MRS in angiogenesis evaluation of soft tissue sarcomas: a prospective clinical study based on MRI-pathology control method

BACKGROUND

The vascular endothelial growth factor (VEGF) and microvessel density (MVD) have been widely employed as angiogenesis indicators in the diagnosis and treatment of soft tissue sarcomas. While diffusion kurtosis imaging (DKI) and proton magnetic resonance spectroscopy (1H-MRS) imaging hold potential in assessing angiogenesis in other tumors, their reliability in correlating with angiogenesis in soft tissue sarcomas remains uncertain, contingent upon accurately acquiring the region of interest (ROI).

METHODS

23 patients with soft tissue sarcomas (STSs) confirmed by pathology were selected, underwent DKI and 1H-MRS at 3.0T MRI. The DKI parameters mean diffusivity (MD), mean kurtosis (MK), kurtosis anisotropy (KA), and 1H-MRS parameters choline (Cho), lipid/lactate (LL) were measured by two radiologists. Two pathologists obtained pathological slices using a new sampling method called MRI-pathology control and evaluated VEGF and MVD in the selected regions. Correlations between MRI parameters and angiogenesis markers were assessed by Person or Spearman tests.

RESULTS

The DKI parameters MD and KA, and the 1H-MRS parameters Cho and LL, have varying degrees of correlation with the expression levels of VEGF and MVD. Among them, Cho exhibits the strongest correlation (r = 0.875, P < 0.001; r = 0.807, P < 0.001).

CONCLUSION

Based on this preliminary clinical studies, DKI and 1H-MRS parameters are correlated with angiogenesis markers obtained through the "MRI-pathology control" method.

NTRK-rearranged spindle cell tumor with SPECC1L-NTRK3 fusion in the thoracic spine: a case report

Neurotrophic Tyrosine Receptor Kinase (NTRK)-rearranged spindle cell tumors are a category of soft tissue tumors characterized by rearrangements of the NTRK gene family (NTRK1, NTRK2, and NTRK3), which leads to distinct molecular genetics, morphological, and immunophenotypic characteristics. The central feature of these tumors is the fusion of NTRK genes with other genes, resulting in abnormal expression and activation of tropomyosin receptor kinase proteins.In this report, we present the first documented case of an NTRK spindle cell tumor with SPECC1L-NTRK3 fusion located in the thoracic spine. This case underscores the diagnostic and therapeutic importance of next-generation sequencing in identifying tumor-specific genetic alterations and selecting targeted therapies. Following 1 month of entrectinib treatment, the patient experienced considerable tumor shrinkage and symptomatic improvement. For bone-derived NTRK-rearranged spindle cell sarcomas, entrectinib shows promising therapeutic efficacy and should be considered a preferred treatment option.

Development and validation of a novel immune-related prognostic model and the potential metastatic mechanism in synovial sarcoma

Background

Several clinical trials have shown that immunotherapy plays a pivotal role in the treatment of patients with metastatic synovial sarcoma. Immune-related genes (IRGs) have been demonstrated to predict the immunotherapy response in certain malignant tumours. However, the clinical significance of IRGs in patients with synovial sarcoma (SS) is still unclear.

Methods

We first combined the immune-related ImmPort gene set to search for SS related to metastatic and differentially expressed immune-related genes (DEIRGs) in the GSE40021 dataset from the GEO database. The soft tissue sarcoma database in TCGA was used for univariate Cox regression analyses to identify DEIRGs that were related to overall survival and to build an immune-related prognostic assessment model.

Results

The study screened a total of six DEIRGs that were closely related to prognosis in metastatic SS. Further analysis showed that there was no significant difference in the expression of several immune checkpoints between the two groups in the GSE40021 data. Moreover, the GREM2 and CTSS genes were significantly expressed in metastatic patients. Further verification of clinical SS tissues from our centre by RT-qPCR analysis demonstrated reduced infiltration of activated NK cells and macrophages but increased M2-type macrophages in metastatic patients. Together, our study successfully constructed an immune-related prognostic assessment model and probably explains the poor efficacy of PD-1 inhibitors for SS patients.

Conclusion

The research deepens our understanding of the tumor immune microenvironment and proposes a new immune mechanism for metastatic SS. Early intervention and reversal of immunosuppressive microenvironmental changes are expected to delay metastasis and improve survival.

Accurate prediction of colorectal cancer diagnosis using machine learning based on immunohistochemistry pathological images

Colorectal cancer (CRC) ranks as the third most prevalent tumor and the second leading cause of mortality. Early and accurate diagnosis holds significant importance in enhancing patient treatment and prognosis. Machine learning technology and bioinformatics have provided novel approaches for cancer diagnosis. This study aims to develop a CRC diagnostic model based on immunohistochemical staining image features using machine learning methods. Initially, CRC disease-specific genes were identified through bioinformatics analysis, SVM-RFE and Random Forest algorithm utilizing RNA-seq data from both GEO and TCGA databases. Subsequently, verification of these genes was performed using proteomics data from CPTAC and HPA database, resulting in identification of target proteins (AKR1B10, CA2, DHRS9, and ZG16) for further investigation. SVM and CNN were then employed to analyze and integrate the characteristics of immunohistochemical images to construct a reliable CRC diagnostic model. During the training and validation process of this model, cross-validation along with external validation methods were implemented to ensure accuracy and reliability. The results demonstrate that the established diagnostic model exhibits excellent performance in distinguishing between CRC and normal controls (accuracy rate: 0.999), thereby presenting potential prospects for clinical application. These findings are expected to provide innovative perspectives as well as methodologies for personalized diagnosis of CRC while offering more precise references for promising treatment.

Beyond the surface: A comprehensive radiological review of primary retroperitoneal neoplasms

Primary retroperitoneal neoplasms (PRNs) are a complex and diverse group of tumors arising in the retroperitoneal space, excluding those from retroperitoneal organs. These masses present significant diagnostic challenges due to their heterogeneous nature. PRNs primarily include sarcomas, neurogenic tumors, extragonadal germ cell tumors, and lymphomas, with the majority being malignant. This necessitates thorough evaluation by radiologists to assess resectability and the need for biopsy. Liposarcomas, the most common primary retroperitoneal sarcomas, and leiomyosarcomas, known for potential vessel involvement, exhibit distinct imaging patterns aiding differentiation. Neurogenic tumors, originating from nerve sheath, ganglionic, or paraganglionic cells, often appear in younger patients and have characteristic imaging features. Primary retroperitoneal extragonadal germ cell tumors are rare and are believed to originate from primordial germ cells that do not successfully migrate during embryonic development. Lymphomas are generally homogeneous on cross-sectional imaging; however, non-Hodgkin lymphomas can sometimes appear heterogeneous, complicating differentiation from other non-lipomatous retroperitoneal masses. Additionally, conditions like retroperitoneal fibrosis and Erdheim-Chester disease can mimic PRNs, complicating diagnosis and management. This review aims to provide radiologists with essential diagnostic points for identifying PRNs, emphasizing the importance of precise imaging interpretation. Understanding these distinctions is vital for guiding clinical management and optimizing patient outcomes.

Magnetic Resonance Imaging Radiomics Predicts Histological Response to Neoadjuvant Chemotherapy in Localized High-grade Osteosarcoma of the Extremities

RATIONALE AND OBJECTIVES

Research involving radiomics models based on magnetic resonance imaging (MRI) has mainly used radiomics features derived from a single MRI sequence at a single time point to develop predictive models. This study aimed to construct radiomics models based on before and after neoadjuvant chemotherapy (NAC) MRI for predicting the histological response to NAC in patients with high-grade osteosarcoma.

MATERIALS AND METHODS

We included 109 patients with localized high-grade osteosarcomas of the extremities, who underwent pre- and post-NAC MRI examinations, from which radiomics features were extracted. According to the tumor necrosis rate, all patients were classified as good responders (GRs) or poor responders (PRs) and were randomly allocated into training and test sets at a 7:3 ratio. Radiomics features were extracted from T2-weighted (T2WI) and contrast-enhanced T1-weighted imaging (T1CE) of the two MRI scans to construct three models: pre-NAC, post-NAC, and combined pre-NAC and post-NAC (combined model).

RESULTS

In total, 1175 radiomics features were extracted from each sequence. Following feature selection, nine radiomics features were selected for each model to construct radiomics signatures. The radiomics signatures of the pre-NAC, post-NAC, and combined models demonstrated good predictive performance for chemotherapy response in osteosarcoma. The combined model achieved the highest areas under the receiver operating curve (AUC) values of 0.999 and 0.915 in the training and test sets, respectively. The AUCs of the post-NAC model were higher than those of the pre-NAC model.

CONCLUSION

MRI-based radiomics models demonstrate excellent performance in predicting the histological response to NAC in patients with high-grade osteosarcoma.

Sarcopenia Is Associated with Neoplasm of Bone and Articular Cartilage: Findings from Mendelian Randomized Study

Exploring the causal relationship between sarcopenia and neoplasm of bone and articular cartilage (NBAC) by bidirectional Mendelian randomization (MR). Genome-wide association study (GWAS) data on sarcopenia-associated traits including appendicular lean mass, low handgrip strength (including criteria from the European Working Group on Sarcopenia in Older People and the Foundation for the National Institutes of Health), and usual walking speeds were obtained from the UK Biobank. GWAS data for NBAC (benign and malignant) were provided by the Finnish Genetic Database. Three different methods of MR analysis, including inverse-variance weighted, Mendelian randomized Egger regression, and weighted median methods, were utilized. MR analysis showed that high appendicular lean mass was positively associated with the risk of developing benign NBAC (odds ratio and 95% confidence interval = 1.236 (1.026,1.489), p = 0.025). At the same time, there is no statistically significant association was found between traits related to sarcopenia and malignant neoplasm of bone and articular cartilage. There was also no reverse causal correlation between NBAC and traits related to sarcopenia. In European populations, better appendicular lean body mass is positively associated with the risk of benign neoplasm of bone and articular cartilage, representing the possibility that sarcopenia may be a protective factor against neoplasm of bone and articular cartilage.

Dedifferentiated recurrent liposarcoma of the uterine corpus: A case report and literature review

Liposarcoma of the uterine corpus represents an exceptionally rare tumor, with few cases documented in the literature, underscoring its unique histopathologic characteristics and management challenges. This case describes the clinical management of a 57-year-old patient with well-differentiated liposarcoma of the uterine corpus who presented with a three-month history of abdominal pain and distension. She underwent an abdominal hysterectomy followed by chemotherapy but experienced local recurrence in the mesentery and retroperitoneum after 21 months. Tumor resection was performed again, followed by chemotherapy, but the patient experienced a second recurrence 15 months later, involving the small intestine, vaginal stump, and ureter, with evidence of dedifferentiated liposarcoma. A third surgical resection was carried out without administering chemotherapy and the patient remained asymptomatic at follow-up appointments every 3 months for a year. This case highlights the importance of acknowledging the aggressive nature of recurrent liposarcoma, especially its transition into dedifferentiated liposarcoma, and the need for tailored management strategies.

Dysregulation of miRNAs in Soft Tissue Sarcomas

MicroRNAs (miRNAs) are pivotal regulators of gene expression, influencing key cellular processes such as proliferation, differentiation, apoptosis, and metastasis. In the realm of sarcomas-a diverse group of malignant tumors affecting soft tissues and bone sarcomas-miRNAs have emerged as crucial players in tumorigenesis and tumor progression. This review delves into the intricate roles of miRNAs across various soft tissue sarcoma subtypes, including rhabdomyosarcoma, liposarcoma, leiomyosarcoma, synovial sarcoma, fibrosarcoma, angiosarcoma, undifferentiated pleomorphic sarcoma (UPS), and malignant peripheral nerve sheath tumor (MPNST). We explore how dysregulated miRNAs function as oncogenes or tumor suppressors, modulating critical pathways that define the aggressive nature of these cancers. Furthermore, we discuss the diagnostic and prognostic potential of specific miRNAs and highlight their promise as therapeutic targets. By understanding the miRNA-mediated regulatory networks, this review aims to provide a comprehensive overview of current research while pointing towards future directions for miRNA-based therapies. Our findings underscore the potential of miRNAs to transform the landscape of sarcoma treatment, offering hope for more precise, personalized, and effective therapeutic strategies.

NTRK3-EML4-rearranged spindle cell tumor with co-expression of S100 and CD34: an unusual mesenchymal tumor in the spectrum of the bland-looking spindle cell lesions of the oral cavity

A novel category of spindle cell tumors characterized by Neurotrophic Tyrosine Receptor Kinase (NTRK) rearrangements with a dual immunoreactivity for S-100 and CD34 has emerged in the last years as a distinct entity among soft tissue neoplasms. These genetic alterations lead to the continuous activation of NTRK genes, driving tumorigenesis and offering a unique prospect for targeted therapy. We herein present a rare case of NTRK3-rearranged spindle cell tumor with a hitherto unreported gene fusion involving the exon 14 of NTRK3 with the exon 2 of Echinoderm Microtubule-Associated Protein-Like 4, arising in the head and neck region. Tumor occurred in a 45-year-old patient who presented with a painful nodule in the oral mucosa. Due to the possibility of personalizing the treatment strategy for such tumors, pathologists should be aware of this emerging group of spindle cell tumors to promptly recognize them even when they occur in uncommon locations, including the oral cavity.

Multifocal malignant perivascular epithelioid cell tumor (PEComa) of the peritoneum: A case report

INTRODUCTION AND IMPORTANCE

Neoplasms with perivascular epithelioid-cell differentiation (PEComa) are rare. We present a case of multifocal malignant PEComas arising in the peritoneum.

CASE PRESENTATION

A 61-year-old woman presented with a painful abdominal mass that had progressed over the past year and recently increased in size. Pelvic magnetic resonance imaging (MRI) showed two masses: an 11-cm partially solid and cystic tumor, with moderate contrast uptake probably originating from the left ovary, and an 18-cm sized, intraperitoneal abdominal heterogeneous enhancing mass. Two nodules in the mesentery and the bladder peritoneum were discovered intraoperatively. The patient underwent Hudson's intervention with resection of the epiploic mass and the two nodules. Microscopic examination revealed a tumor proliferation of epithelioid clear cells with delicate vascular septae. Immunohistochemistry was positive for HMB45, MelanA and SMA. The final diagnosis of a malignant PEComa was retained. The patient developed two local peritoneal recurrences and died after 26 months of follow-up.

CLINICAL DISCUSSION

Our case is original by its multifocal presentation being the seventh case of a multifocal malignant PEComa reported in the literature. PEComa's clinical presentation and radiographic appearance can often mimic a soft tissue clear cell sarcoma.

CONCLUSION

Clinical and pathological correlations are mandatory to make a precise diagnosis and adapt the treatment of PEComas.

Trabectedin for L-Type Sarcoma: A Retrospective Multicenter Study

(1) Background: Metastatic L-type sarcomas (liposarcoma and leiomyosarcoma) are rare and have a poor prognosis. Trabectedin is an effective agent that can be used after anthracyclines. This study was designed to evaluate the real-life effectiveness and safety of trabectedin. (2) Methods: A retrospective multicenter study was conducted on patients who were treated with trabectedin for metastatic L-type sarcomas at ten tertiary oncology centers between 2015 and 2023. The objective response rate (ORR), disease control rate (DCR), time to treatment failure (TTF), and overall survival (OS) were evaluated in the cohort. Cox regression analysis was used to determine prognostic factors for survival. (3) Results: A total of 98 patients (52% liposarcoma and 48% leiomyosarcoma) were included in the study. The median treatment line was three (range: 1 to 6). Thirteen patients (13.3%) underwent local treatment due to oligoprogression, and dose reduction was required in seventeen patients (17.3%) due to toxicity. The ORR and DCR were 16% and 42%, respectively. The median TTF was 3 months, and the median OS was 10 months. In univariate analysis, a significantly longer median TTF was observed in patients who underwent local treatment (p = 0.008), obtained objective responses (p < 0.001), and underwent dose reduction (p = 0.002). No statistical differences were observed according to the histologic subtype and metastatic site. In the multivariate analysis for OS, it was found that obtaining an objective response was a good prognostic factor (p = 0.003), while the presence of liver metastases was associated with a poor prognosis (p = 0.016). (4) Conclusion: Trabectedin is a suitable option for L-type sarcoma after doxorubicin-based treatments. Survival was not worse in patients who underwent dose reduction. The use of local therapies simultaneously with trabectedin can be effective.

Patterns of expression of VEGFR2, PDGFRs and c-Kit in pediatric patients with high grade non-rhabdomyosarcoma soft tissue sarcoma

Introduction

Activated vascular endothelial growth factor receptors (VEGFRs), platelet-derived growth factor receptors (PDGFRs) and c-Kit have been shown to be involved in the growth, invasion and metastasis of non-rhabdomyosarcoma soft tissue sarcoma tumor (NRSTS) with promising results for targeted therapy. Our aim was to assess the expression of these markers among different histological types and correlate with outcomes.

Material and methods

This retrospective study included pediatric patients aged ≤ 18 years diagnosed with high-grade NRSTS who were treated at Children Cancer Hospital Egypt 57357 as per the COG NRSTS protocol (ARST0332). Expression of VEGFR2, PDGFRs (α and β) and c-Kit in tumor tissue was assessed by immunohistochemistry and correlated with clinical outcome.

Results

Of 113 patients, 96 were eligible for the analysis with a median age of 11 years. Overall, 32.3% demonstrated high expression of PDGFRα, 17.7% for PDGFRβ, 19.8% for VEGFR2 and 8.3% exhibited positive expression for c-kit on the tumor cells. Most cases of synovial sarcoma (45.8%) and 43.7% of patients with undifferentiated sarcoma exhibited high expression of PDGFRα while 41.6% of MPNST showed high expression to PDGFRβ. The 5-year overall survival (OS), event free survival and relapse free survival (RFS) for the whole cohort were 59%, 54% and 60% respectively. In univariate analyses, only PDGFRα had a negative prognostic impact on relapse free survival (RFS) (p=0.03). In multivariate analyses, VEGFR2 was found to have a negative prognostic impact for OS (p = 0.02).

Conclusion

Our findings indicated that tyrosine kinase receptors are upregulated in NRSTS and exhibited a distinct expression pattern within various subgroups. High expression of VEGFR2 and PDGFRα significantly correlated with reduced survival and may guide targeted therapy approaches for this poor prognosis group of patients.

Rare primary dedifferentiated liposarcoma of the thoracic spine: A case report and literature review

Introduction

Primary dedifferentiated liposarcomas of the spine mark a rare tumor entity.

Research question and case description

We present a rare case of a primary dedifferentiated liposarcoma of the thoracic spine. A 36-year-old previously completely healthy woman presented with a sudden ascending paresthesia of both legs, persistently increasing over the course of two days before initial presentation.

Case report

Computed tomography and magnetic resonance imaging revealed an expansively growing tumor mass extending from T5 to T6 and absolutely compressing the dural sac and spinal cord. The patient's neurological function completely recovered after emergency posterior decompression via laminectomy with intralesional tumor debulking. The tumor was histologically classified as primary grade 2 dedifferentiated liposarcoma (DDLPS) of the spine and after referral to a sarcoma center, the patient was treated with three courses of polychemotherapy (doxorubicin plus ifosfamide). Chemotherapy was followed by aggressive resection by en-bloc spondylectomy in cooperation with a spine tumor center. Subsequently, the patient also underwent radiation therapy.

Results

The patient still undergoes structured tumor aftercare and is tumor- and metastasis-free 53 months after tumor resection.

Discussion and conclusion

DDLPS rarely occur in the spine, with definitive resection of the tumor being the treatment of choice. Surgery should be accompanied by other (radio-) oncological treatment options in cases where only subtotal resection is possible. Also, referral of patients with primary sarcomas of the spine to specialized sarcoma centers is essential, so they can be provided with individual treatment options and structured interdisciplinary aftercare, that ensure the best possible outcome.

Prognostic factors of cutaneous soft tissue sarcomas in children: a SEER population-based study

This study aims to analyze the clinicopathological characteristics and survival outcomes of cutaneous soft tissue sarcomas (CSTS) in children. We selected pediatric cases of CSTS diagnosed between 2000 and 2019 from the Surveillance, Epidemiology, and End Results (SEER) database. Survival rates were calculated using Kaplan-Meier methods. We performed univariate analyses with the log-rank test and multivariate survival analyses using Cox proportional-hazards models to determine factors affecting overall survival (OS). Additionally, we constructed a predictive nomogram based on the outcomes of the Cox regression. A total of 148 pediatric patients with CSTS were reviewed. The median age at diagnosis was 13 years (range: 0-18 years). Prognostically, tumors located on the extremities showed better outcomes compared to those on the head, neck, or trunk. Among the histological types, angiosarcoma had the lowest five-year survival rate at 51.3%, which was substantially lower compared to fibrous histiocytoma and leiomyosarcoma. Cox regression analysis highlighted surgical intervention as the only significant independent prognostic factor for OS, with an increased risk of mortality observed in patients not undergoing surgery. Additionally, patients with distant-stage disease exhibited significantly lower survival rates than those with localized conditions. Pediatric CSTS represents a diverse and infrequent group of tumors, predominantly fibrous histiocytoma and leiomyosarcoma. Surgery was identified as the crucial determinant of survival, underscoring its role in effectively managing these patients.

Giant ganglioneuroma of the mediastinum: a case report

Ganglioneuroma (GN) is a rare benign neurogenic tumor that originates from the sympathetic nerves. It is extremely uncommon to find a lesion originating from the mediastinum that occupies the entire left hemithorax. In this report, we present the case of a 48-year-old female patient with a large mediastinal GN who presented with cough, sputum, and wheezing. Multislice spiral-enhanced CT and magnetic resonance imaging (MRI) revealed a large oval mass in the left thoracic cavity. The surgical operation completely resected the lesion, and the histopathological examination of the resected specimen confirmed the diagnosis of giant ganglion cell neuroma of the mediastinum. Due to the low incidence of GN and the lack of specific imaging manifestations, many radiologists may lack sufficient knowledge of GN and may be prone to misdiagnosis, resulting in delayed treatment. To enhance radiologists' awareness of giant ganglion cell neuroma of mediastinal origin occupying the thoracic cavity, we provided detailed CT/MRI imaging information for this case, along with a brief summary of similar previously reported cases, to highlight the specific clinical and radiological features of this condition.

Genetic and Molecular Heterogeneity of Synovial Sarcoma and Associated Challenges in Therapy

Synovial sarcoma (SS) is one of the most common types of pediatric soft tissue sarcoma (STS) being far less frequent in adults. This STS type is characterized by one specific chromosomal translocation SS18-SSX and the associated changes in signaling. However, other genetic and epigenetic abnormalities in SS do not necessarily include SS18-SSX-related events, but abnormalities are more sporadic and do not correlate well with the prognosis and response to therapy. Currently, targeted therapy for synovial sarcoma includes a limited range of drugs, and surgical resection is the mainstay treatment for localized cancer with adjuvant or neoadjuvant chemotherapy and radiotherapy. Understanding the molecular characteristics of synovial sarcoma subtypes is becoming increasingly important for detecting new potential targets and developing innovative therapies. Novel approaches to treating synovial sarcoma include immune-based therapies (such as TCR-T cell therapy to NY-ESO-1, MAGE4, PRAME or using immune checkpoint inhibitors), epigenetic modifiers (HDAC inhibitors, EZH2 inhibitors, BRD disruptors), as well as novel or repurposed receptor tyrosine kinase inhibitors. In the presented review, we aimed to summarize the genetic and epigenetic landscape of SS as well as to find out the potential niches for the development of novel diagnostics and therapies.