Malignant Chest Wall Tumors: Complex Defects and Their Management-A Review of 181 Cases.

BACKGROUND: Chest wall tumors are a heterogeneous group of tumors that are managed by surgeons from diverse specialties. Due to their rarity, there is no consensus on their diagnosis and management. MATERIALS: This retrospective, descriptive analysis includes patients with malignant chest wall tumors undergoing chest wall resection. Tumors were classified as primary, secondary, and metastatic tumors. The analysis includes clinicopathological characteristics, resection-reconstruction profile, and relapse patterns. RESULTS: A total of 181 patients underwent chest wall resection between 1999 and 2020. In primary tumors (69%), the majority were soft tissue tumors (59%). In secondary tumors, the majority were from the breast (45%) and lung (42%). Twenty-five percent of patients received neoadjuvant chemotherapy, and 98% of patients underwent R0 resection. Soft tissue, skeletal + soft tissue, and extended resections were performed in 45%, 70%, and 28% of patients, respectively. The majority of patients (60%) underwent rib resections, and a median of 3.5 ribs were resected. The mean defect size was 24 cm2. Soft tissue reconstruction was performed in 40% of patients, mostly with latissimus dorsi flaps. Rigid reconstruction was performed in 57% of patients, and 18% underwent mesh-bone cement sandwich technique reconstruction. Adjuvant radiotherapy and chemotherapy were given to 29% and 39% of patients, respectively. CONCLUSIONS: This is one of the largest single-institutional experiences on malignant chest wall tumors. The results highlight varied tumor spectra and multimodality approaches for optimal functional and survival outcomes. In limited resource setting, surgery, including reconstructive expertise, is very crucial.

Evaluating the Alignment of Artificial Intelligence-Generated Recommendations With Clinical Guidelines Focused on Soft Tissue Tumors.

BACKGROUND: The integration of artificial intelligence (AI), particularly, in oncology, has significantly shifted the paradigms of medical diagnostics and treatment planning. However, the utility of AI, specifically OpenAI's ChatGPT, in soft tissue sarcoma treatment, remains unclear. METHODS: We evaluated ChatGPT's alignment with the Japanese Orthopaedic Association (JOA) clinical practice guidelines on the management of soft tissue tumors 2020. Twenty-two clinical questions (CQs) were formulated to encompass various aspects of sarcoma diagnosis, treatment, and management. ChatGPT's responses were classified into "Complete Alignment," "Partial Alignment," or "Nonalignment" based on the recommendation and strength of evidence. RESULTS: ChatGPT demonstrated an 86% alignment rate with the JOA guidelines. The AI provided two instances of complete alignment and 17 instances of partial alignment, indicating a strong capability to match guideline criteria for most questions. However, three discrepancies were identified in areas concerning the treatment of atypical lipomatous tumors, perioperative chemotherapy for synovial sarcoma, and treatment strategies for elderly patients with malignant soft tissue tumors. Reassessment with guideline input led to some adjustments, revealing both the potential and limitations of AI in complex sarcoma care. CONCLUSION: Our study demonstrates that AI, specifically ChatGPT, can align with clinical guidelines for soft tissue sarcoma treatment. It also underscores the need for continuous refinement and cautious integration of AI in medical decision-making, particularly in the context of treatment for soft tissue sarcoma.

A case of cutaneous malignant glomus tumor.

Glomus tumors are well-known but relatively rare vascular neoplasms, with their malignant counterparts still being rarer. There are very few reports of cutaneous malignant glomus tumors, and the current limited evidence suggests that they follow a more indolent course than deep-seated malignant glomus tumors. Herein, we are reporting a case of cutaneous malignant glomus tumor. A 94-year-old male presented with a right-sided ulcerated scalp lesion, which, on biopsy, showed a diffusely infiltrative epithelioid malignancy with considerable pleomorphism and a notable perivascular growth pattern. The tumor cells were positive for smooth muscle actin (SMA) and h-caldesmon, and negative for cytokeratin MNF116, CK5, p40, S100, SOX10, HMB45, Melan-A, ERG, CD31, CD45, CD3, CD20, ALK, desmin, CD68, CD34, and HHV8. A diagnosis of cutaneous malignant glomus tumor was made, and the patient underwent a wider excision. Cutaneous malignant glomus tumors are extremely rare and should be considered when examining unusual cutaneous mesenchymal tumors.

Pitfalls in soft tissue cytopathology.

Fine needle aspiration biopsy (FNAB) is a diagnostic modality for the evaluation of suspicious soft tissue masses. Despite its reasonable sensitivity, specificity and positive predictive value in differentiating benign from malignant neoplasms, the exact subtyping of the primary soft tissue tumours can be challenging. Certain tumours constitute "pitfalls" and add to the diagnostic challenge. This review provides a detailed account of the diagnostic challenges in soft tissue cytopathology, including pitfalls and, more importantly, the ways to overcome these challenges by integrating clinical details, key cytomorphological features and judicious application of ancillary techniques.

Unresectable infantile myofibroma discovered in utero.

The authors present a case of a proliferative nodule located beneath an infant's lower lip that was initially discovered on prenatal ultrasound and fetal magnetic resonance imaging (MRI). Biopsy revealed a smooth muscle actin-positive spindled cell proliferation with hemangiopericytoma-like vessels consistent with infantile myofibromatosis (IM). Since the location prevented surgical management, the clinicians opted to observe the lesion. Ultimately, the lesion fully regressed on its own confirming conservative management is an option for isolated IM.

MRI features of benign peripheral nerve sheath tumors: how do sporadic and syndromic tumors differ?

OBJECTIVES: To compare MRI features of sporadic and neurofibromatosis syndrome-related localized schwannomas and neurofibromas. METHODS: In this retrospective study, our pathology database was searched for "neurofibroma" or "schwannoma" from 2014 to 2019. Exclusion criteria were lack of available MRI and intradural or plexiform tumors. Qualitative and quantitative anatomic (location, size, relationship to nerve, signal, muscle denervation) and functional (arterial enhancement, apparent diffusion-weighted coefficient) MRI features of sporadic and syndrome-related tumors were compared. Statistical significance was assumed for p < 0.05. RESULTS: A total of 80 patients with 64 schwannomas (sporadic: 42 (65.6%) v. syndrome-related: 22 (34.4%)) and 19 neurofibromas (sporadic: 7 (36.8%) v. syndrome-related: 12 (41.7%)) were included. Only signal heterogeneity (T2W p=0.001, post-contrast p=0.03) and a diffused-weighted imaging target sign (p=0.04) were more frequent with schwannomas than neurofibromas. Sporadic schwannomas were similar in size to syndrome-related schwannomas (2.9±1.2cm vs. 3.7±3.2 cm, p = 0.6), but with greater heterogeneity (T2W p = 0.02, post-contrast p = 0.01). Sporadic neurofibromas were larger (4.6±1.5cm vs. 3.4±2.4 cm, p = 0.03) than syndrome-related neurofibromas, also with greater heterogeneity (T2W p=0.03, post-contrast p=0.04). Additional tumors along an affected nerve were only observed with syndrome-related tumors). There was no difference in apparent diffusion coefficient values or presence of early perfusion between sporadic and syndrome-related tumors (p > 0.05). CONCLUSIONS: Although syndrome-related and sporadic schwannomas and neurofibromas overlap in their anatomic, diffusion and perfusion features, signal heterogeneity and presence of multiple lesions along a nerve are differentiating characteristics of syndrome-related tumors.

RNA Sequencing Reveals Novel Oncogenic Fusions and Depicts Detailed Fusion Transcripts of FN1-FGFR1 in Phosphaturic Mesenchymal Tumors.

Phosphaturic mesenchymal tumors (PMTs) are rare neoplasms of soft tissue or bone. Although previous studies revealed that approximately 50% of PMTs harbor FN1::FGFR1 fusions, the molecular mechanisms in the remaining cases are largely unknown. In this study, fusion genes were investigated using RNA-based next-generation sequencing in 76 retrospectively collected PMTs. Novel fusions were validated with Sanger sequencing and fluorescence in situ hybridization. Fusion genes were detected in 52/76 (68.4%) PMTs, and 43/76 (56.6%) harbored FN1::FGFR1 fusions. Fusion transcripts and breakpoints of the FN1::FGFR1 fusions were diverse. The most common fusion transcript was between exon 20 of FN1 and exon 9 of FGFR1 (7/43, 16.3%). The most upstream breakpoint of the FN1 gene was located at the 3' end of exon 12, and the most downstream breakpoint of the FGFR1 gene was at the 5' end of exon 9, suggesting the inessential nature of the third fibronectin-type domain of FN1 and the necessity of the transmembrane domain of FGFR1 in the FN1::FGFR1 fusion protein, respectively. Moreover, the reciprocal FGFR1::FN1 fusions, which had not been identified in previous studies, were detected in 18.6% (8/43) of FN1::FGFR1 fusion-positive PMTs. Novel fusions were identified in 6/76 (7.9%) FN1::FGFR1 fusion-negative PMTs, including 2 involving FGFR: FGFR1::USP33 (1/76, 1.3%) and FGFR1::TLN1 (1/76, 1.3%). Other novel fusions identified were the PDGFRA::USP35 (1/76, 1.3%), SPTBN1::YWHAQ (1/76, 1.3%), GTF2I::RALGPS1 (1/76, 1.3%), and LTBP1::VWA8 (1/76, 1.3%) fusions. In addition to these novel fusions, FN1::FGFR2 (1/76, 1.3%), NIPBL::BEND2 (1/76, 1.3%), and KIAA1549::BRAF fusions (1/76, 1.3%) were also identified in FN1::FGFR1-negative cases arising from the thigh, ilium, and acetabulum, respectively. The frequency of oncogenic fusions was significantly higher (P = .012) in tumors derived from extremities (29/35, 82.9%) compared with other locations (23/41, 56.1%). No significant correlation was identified between fusions and recurrence (P = .786). In conclusion, we report fusion transcripts and breakpoints of FN1::FGFR1 in PMTs in detail, providing insights into fusion protein functions. We also revealed that a considerable proportion of PMTs without FN1::FGFR1 fusion carried novel fusions, providing further insight into the genetic basis of PMTs.

MRI Fat-Saturated T2-Weighted Radiomics Model for Identifying the Ki-67 Index of Soft Tissue Sarcomas.

BACKGROUND: Ki-67 expression has been shown to be an important risk factor associated with prognosis in patients with soft tissue sarcomas (STSs). Its assessment requires fine-needle biopsy and its accuracy can be influenced by tumor heterogeneity. PURPOSE: To develop and test an MRI-based radiomics nomogram for identifying the Ki-67 status of STSs. STUDY TYPE: Retrospective. POPULATION: A total of 149 patients at two independent institutions (training cohort [high Ki-67/low ki-67]: 102 [52/50], external validation cohort [high Ki-67/low ki-67]: 47 [28/19]) with STSs. FIELD STRENGTH/SEQUENCE: Fat-saturated T2-weighted imaging (FS-T2WI) with a fat-suppressed fast spin/turbo spin echo sequence at 1.5 T or 3 T. ASSESSMENT: After radiomics feature extraction, logistic regression (LR), random forest (RF), support vector machine (SVM), and k-nearest neighbor (KNN) were used to construct radiomics models to distinguish between high and low Ki-67 status. Clinical-MRI characteristics included age, gender, location, size, margin, and MRI morphological features (size, margin, signal intensity, and peritumoral hyperintensity) were assessed. Univariate and multivariate logistic regression analysis were applied for screening significant risk factors. Radiomics nomogram was constructed by radiomics signature and risk factors. STATISTICAL TESTS: Model performances (discrimination, calibration, and clinical usefulness) were validated in the validation cohort. The nomogram was assessed using the Harrell index of concordance (C-index), calibration curve analysis. The clinical utility of the model was assessed by decision curve analysis (DCA). RESULTS: LR, RF, SVM, and KNN models represented AUCs of 0.789, 0.755, 0.726, and 0.701 in the validation cohort (P > 0.05). The nomogram had a C-index of 0.895 (95% CI: 0.837-0.953) in the training cohort and 0.852 (95% CI: 0.796-0.957) in the validation cohort and it demonstrated good calibration and clinical utility (P = 0.972 for the training cohort and P = 0.727 for the validation cohort). DATA CONCLUSION: This MRI-based radiomics nomogram developed showed good performance in identifying Ki-67 expression status in STSs. TECHNICAL EFFICACY STAGE: 2.

Incidence of radiation-associated sarcoma after breast-conserving surgery plus radiation.

BACKGROUND: Radiation-associated sarcoma (RAS) is a rare sequela of radiotherapy. Radiotherapy modalities for breast conservation and radiation treatment (BCT) have changed over time. We sought to determine if the incidence of RAS after BCT has changed over time. METHODS: We identified breast cancer survivors (diagnosed 1988-2012) treated with BCT within the SEER database. We excluded patients with prior cancer, <1-year follow-up/survival, and nonexternal beam radiation (n = 276 301). We identified patients with a subsequent chest sarcoma diagnosis. The primary predictor variable was a 5-year period of breast cancer diagnosis year (1988-1992, 1993-1997, etc.). The incidence of sarcoma was estimated by the Kaplan-Meier method, censoring at sarcoma diagnosis, death, or last follow-up (available through December 2017). Given the known latency of RAS, we used Joinpoint analysis to identify the time point at which RAS incidence significantly increased (start of the analytic window). A log-rank test assessed differences in RAS incidence by diagnosis year. RESULTS: The incidence of RAS was 0.03% at 5 years (95% confidence interval [CI]: 0.03-0.04) and 0.16% at 10 years (95% CI: 0.14-0.18). No statistical difference in RAS incidence by diagnosis year was observed (p = 0.2). CONCLUSIONS: RAS remains a rare but persistent sequela after BCT. As new radiation modalities become more common, ongoing surveillance is necessary to track these rare events.

Effects of time to treatment initiation on outcomes for soft tissue sarcomas.

BACKGROUND AND OBJECTIVES: Few studies have investigated the effects of time to treatment initiation (TTI) for soft tissue sarcomas (STS). Our objective was to investigate the risk factors for prolonged TTI and the effects of prolonged TTI on local recurrence free survival (LRFS), distant metastasis free survival (DMFS), and disease specific survival (DSS). METHOD: Patients diagnosed with high-grade STS of the extremities and trunk from 2011 to 2020 were included. TTI was grouped into two groups (treatment provided in less than vs. more than or equal to 30 days). Two-year and 5-year survival probabilities were calculated for LRFS, DMFS, and DSS. Cox regression and Kruskal-Wallis tests in univariate analysis were conducted to find risk factors affecting TTI and the survival outcomes. RESULTS: In the univariate analysis, diagnosis in the later 5-year period of the study, tumor size, and treatment modality were associated with prolonged TTI. TTI ≥30 days was associated with higher DMFS but no association was found with LRFS or DSS. Tumor size, surgical margins, and provision of surgery were associated with DSS. CONCLUSION: Despite the delay in treatment for STS patients caused by the COVID-19 pandemic, our study showed TTI of more than 30 days does not negatively impact patients.

Extramammary myofibroblastoma of the oral cavity.

Myofibroblastoma is a rare, benign mesenchymal tumor first described as a neoplasm of the breast. Extramammary myofibroblastoma is a histopathologically and genetically identical lesion occurring outside the breast. Herein is presented a case of extramammary myofibroblastoma arising in the oral cavity. A 59-year-old woman presented with a 1.5 cm nodule on the buccal surface of the lower lip. Wide local excision was performed. Histopathologic examination revealed haphazard fascicles of monomorphic spindle cells with hyalinized collagen bundles without fat. The spindled cells were diffusely positive for CD34, and focally for progesterone receptor. Desmin, smooth muscle actin, estrogen receptor, androgen receptor, S100, and STAT6 were negative. Rb1 expression was lost in tumor cells. Thus, the diagnosis of extramammary myofibroblastoma was made. Differential diagnoses include spindle-cell lipoma and angiofibroma. All three tumors are members of the 13q14 deletion/RB1 loss family. Indolent but locally aggressive (solitary fibrous tumor, desmoid fibromatosis) and frankly malignant (low-grade peripheral nerve sheath tumor, dermatofibrosarcoma protuberans) entities can be excluded by immunohistochemistry and careful microscopic examination. Extensive sampling extramammary myofibroblastoma is important to exclude the possibility of malignancy. Clinicians and pathologists alike should be aware of this entity and its potential to arise rarely in unusual locations.

Diagnostic accuracy of multiparametric ultrasound for peripheral nerve schwannoma.

BACKGROUND: Ultrasound (US) diagnostic techniques have the advantages of low cost, convenient operation, and high availability. PURPOSE: To explore the diagnostic accuracy of multiparametric US in evaluating signs of peripheral schwannoma. MATERIAL AND METHODS: This retrospective case-control study included patients with soft-tissue masses on the limbs (divided into the schwannoma and non-schwannoma groups) between January 2017 and November 2020. US features were compared between the two groups, and receiver operating characteristics analysis was used to evaluate the diagnostic efficacy of these features. RESULTS: A total of 165 patients were included in this study; of them, 63 (38.2%) were diagnosed with schwannoma. Regular morphology (95.2% vs. 39.2%), cystic degeneration (71.4% vs. 27.5%), target sign on elastography (82.5% vs. 0), and polar blood supply sign (87.3% vs. 14.7%) were more common in schwannomas than in non-schwannoma lesions (all P < 0.001). Combining the four signs for diagnosis of schwannomas, the sensitivity, specificity, and accuracy were 95.24%, 96.08%, and 95.76%, respectively, with an area under the curve (AUC) of 0.987 (95% confidence interval = 0.955-0.998). Entering and exiting nerve sign was observed in 87.3% of schwannomas and in 3.0% of non-schwannoma lesions (P < 0.001), while split-fat sign was similar between the two groups (9.5% vs. 2.0%; P = 0.068). CONCLUSION: Polar blood supply sign and target sign on elastography are specific US signs in peripheral schwannomas. The combination of two-dimensional imaging, color flow imaging, and elastography can achieve an excellent diagnostic accuracy in schwannomas.

Musculoskeletal oncology and thermal ablation: the current and emerging role of interventional radiology.

The role of interventional radiology (IR) is expanding. With new techniques being developed and tested, this radiology subspecialty is taking a step forward in different clinical scenarios, especially in oncology. Musculoskeletal tumoral diseases would definitely benefit from a low-invasive approach that could reduce mortality and morbidity in particular. Thermal ablation through IR has already become important in the palliation and consolidation of bone metastases, oligometastatic disease, local recurrences, and treating specific benign tumors, with a more tailored approach, considering the characteristics of every patient. As image-guided ablation techniques lower their invasiveness and increase their efficacy while the collateral effects and complications decrease, they become more relevant and need to be considered in patient care pathways and clinical management, to improve outcomes. We present a literature review of the different percutaneous and non-invasive image-guided thermal ablation methods that are currently available and that could in the future become relevant to manage musculoskeletal oncologic diseases.

Immunohistochemical and molecular updates in cutaneous soft tissue neoplasms.

Accurate classification of soft tissue neoplasms of the skin and subcutis can be challenging given the sometimes significant histomorphologic and immunohistochemical overlap between the entities that comprise this ever-expanding category of tumors. With the benefit of continually emerging adjuncts to histologic diagnosis, pathologists have a number of tools at their disposal for navigating this group of neoplasms. This article aims to review recent immunohistochemical and molecular updates in the diagnosis of cutaneous soft tissue neoplasms.

[Giant cell-containing tumors of bone and differential diagnoses]. / Riesenzell-haltige Tumoren des Knochens und Differenzialdiagnosen.

Osteoclastic giant cells represent a common cellular component of lesions arising in bone. Highlighting this morphological finding, the current WHO classification of bone tumors defines a diagnostic group comprising aneurysmal bone cyst, giant cell tumor of bone and non-ossifying fibroma, which may display morphologic similarities while being distinct with regard to molecular and biological features. Starting with these tumors - putting a focus on lesions arising in bone - this article gives a survey of other (chondrogenic and osteogenic) tumors that frequently contain osteoclastic giant cells, which may, particularly in small biopsies, enter differential diagnosis. Overlapping features with selected giant cell-containing soft tissue tumors, which may be of differential diagnostic relevance in daily routine, are discussed.

Orbital myopericytoma: an unusual tumor in an unusual location.

A 71-year-old male with a 4-month history of bulging, tearing, and redness in the right eye presented with vision loss, proptosis, conjunctival hyperemia, and chemosis. Magnetic resonance imaging showed a right intraconal solid mass with extraconal extension, hyper-intense in T2 sequences with heterogeneous contrast enhancement. Complete excision of the mass was performed through a lateral orbitotomy. Histological analysis revealed a neoplasm with high vessel density, solid growth of oval cells, a concentric proliferation of the wall of small vessels, and a weak and patchy positivity for smooth muscle actin. These findings were consistent with the diagnosis of myopericytoma. After surgery, visual acuity improved in the affected eye and after 18 months of follow-up there have been no signs of recurrence.

Whole-exome sequencing reveals novel vacuolar ATPase genes' variants and variants in genes involved in lysosomal biology and autophagosomal formation in oral granular cell tumors.

BACKGROUND: Granular cell tumors (GCTs) are rare neuroectodermal soft tissue neoplasms that mainly affect the skin of the upper limbs and trunks and the oral cavity. GCTs are derived from Schwann cells and, ultrastructurally, their intracytoplasmic granules are considered autophagosomes or autophagolysosomes and are consistent with myelin accumulation. METHODS: In this study, a convenience set of 22 formalin-fixed, paraffin-embedded samples of oral GCTs, all but one sample located at the tongue, was screened for mutations by whole-exome (WES) or targeted sequencing. RESULTS: WES revealed two novel variants in genes of the vacuolar ATPase (V-ATPase) complex: ATP6AP1 frameshift c.746_749del, leading to p.P249Hfs*4, and ATP6V1A non-synonymous c.G868A, leading to p.D290N. Each of these mutations occurred in one case. With regard to the samples that were wild type for these V-ATPase variants, at least two samples presented variants in genes that are part of endosomal/lysosomal/autophagosomal networks including ABCA8, ABCC6, AGAP3, ATG9A, CTSB, DNAJC13, GALC, NPC1, SLC15A3, SLC31A2, and TMEM104. CONCLUSION: Although the mechanisms involved in oral GCT initiation and progression remain unclear, our results suggest that oral GCTs have V-ATPase variants similarly to GCTs from other tissues/organs, and additionally show variants in lysosomes/endosomes/autophagosomal genes.

Rhabdomyomatous mesenchymal hamartoma presenting as telangiectasia in a 57-year-old man.

Rhabdomyomatous mesenchymal hamartoma (RMH) is a rare congenital malformation of the dermis and subcutaneous tissue. Usually, RMH occurs in the midline of the face and neck region. We described a case of RMH presenting as telangiectasia in a 57-year-old man with a history of pityriasis lichenoides chronicus. Histopathological examination revealed a subepidermal haphazard proliferation of striated muscular tissue perpendicular to the epidermis. These bundles of striated muscular tissue were admixed with adnexal structures. The diagnosis was consistent with RMH. RMH is more common in the neonatal period or in young children, but we should consider it as part of a differential diagnosis in older adults as well.

Comparative cytological and histological assessment of 828 primary soft tissue and bone lesions, and proposal for a system for reporting soft tissue cytopathology.

INTRODUCTION: The aim of the study was to evaluate the diagnostic utility of fine needle aspiration (FNA) cytology and core needle biopsies (CNBs) in a series of primary soft tissue and bone lesions and to test a possible system for reporting results of FNA cytology of soft tissue lesion. METHODS: This retrospective study encompassed 828 primary soft tissue and bone lesions, analysed with FNA, CNB and/or surgical specimen in order to perform sensitivity/specificity as well as accuracy analyses. The series was then used to test a system for reporting soft tissue cytopathology with six categories and the risk of malignancy in each category was calculated. RESULTS: With a malignant diagnosis defined as positive test result, FNA and CNB analysis showed sensitivity of 87% and 94%, respectively, and specificity of 89% and 95%, respectively. FNA and CNB analyses identified the correct histopathological entity of the examined lesion in 55% and 66%, respectively. The risk of malignancy within the tested categories was non-diagnostic 42%, non-neoplastic 0%, atypia of unknown significance 46%, neoplasm benign 3%, neoplasm of unknown malignant potential 27%, suspicious for malignancy 72% and malignant 97%. CONCLUSION: FNA cytology is a suitable tool to determine the malignant potential of a sampled soft tissue/bone lesion but is inferior to CNB in defining the correct entity. A standardised reporting system might improve the clinical management of patients with soft tissue tumours examined primarily by FNA cytology.

Soft tissue pathology for the radiologist: a tumor board primer with 2020 WHO classification update.

Radiologists serve an important role in the diagnosis and staging of soft tissue tumors, often through participation in multidisciplinary tumor board teams. While an important function of the radiologist is to review pertinent imaging and assist in the differential diagnosis, a critical role is to ensure that there is concordance between the imaging and the pathologic diagnosis. This requires a basic understanding of the pathology of soft tissue tumors, particularly in the case of diagnostic dilemmas or incongruent imaging and histologic features. This work is intended to provide an overview of soft tissue pathology for the radiologist to optimize participation in multidisciplinary orthopedic oncology tumor boards, allowing for contribution to management decisions with expertise beyond image interpretation.