Soft tissue tumor imaging in adults: whole-body staging in sarcoma, non-malignant entities requiring special algorithms, pitfalls and special imaging aspects. Guidelines 2024 from the European Society of Musculoskeletal Radiology (ESSR).

OBJECTIVES: The revised European Society of Musculoskeletal Radiology (ESSR) consensus guidelines on soft tissue tumor imaging represent an update of 2015 after technical advancements, further insights into specific entities, and revised World Health Organization (2020) and AJCC (2017) classifications. This second of three papers covers algorithms once histology is confirmed: (1) standardized whole-body staging, (2) special algorithms for non-malignant entities, and (3) multiplicity, genetic tumor syndromes, and pitfalls. MATERIALS AND METHODS: A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements that had undergone interdisciplinary revision were scored online by the level of agreement (0 to 10) during two iterative rounds, that could result in 'group consensus', 'group agreement', or 'lack of agreement'. RESULTS: The three sections contain 24 statements with comments. Group consensus was reached in 95.8% and group agreement in 4.2%. For whole-body staging, pulmonary MDCT should be performed in all high-grade sarcomas. Whole-body MRI is preferred for staging bone metastasis, with [18F]FDG-PET/CT as an alternative modality in PET-avid tumors. Patients with alveolar soft part sarcoma, clear cell sarcoma, and angiosarcoma should be screened for brain metastases. Special algorithms are recommended for entities such as rhabdomyosarcoma, extraskeletal Ewing sarcoma, myxoid liposarcoma, and neurofibromatosis type 1 associated malignant peripheral nerve sheath tumors. Satisfaction of search should be avoided in potential multiplicity. CONCLUSION: Standardized whole-body staging includes pulmonary MDCT in all high-grade sarcomas; entity-dependent modifications and specific algorithms are recommended for sarcomas and non-malignant soft tissue tumors. CLINICAL RELEVANCE STATEMENT: These updated ESSR soft tissue tumor imaging guidelines aim to provide support in decision-making, helping to avoid common pitfalls, by providing general and entity-specific algorithms, techniques, and reporting recommendations for whole-body staging in sarcoma and non-malignant soft tissue tumors. KEY POINTS: An early, accurate, diagnosis is crucial for the prognosis of patients with soft tissue tumors. These updated guidelines provide best practice expert consensus for standardized imaging algorithms, techniques, and reporting. Standardization can improve the comparability examinations and provide databases for large data analysis.

MR-guided focused ultrasound therapy of extra-abdominal desmoid tumors: a multicenter retrospective study of 105 patients.

OBJECTIVE: To assess the safety and efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) for the treatment extra-abdominal desmoids. METHODS: A total of 105 patients with desmoid fibromatosis (79 females, 26 males; 35 ± 14 years) were treated with MRgFUS between 2011 and 2021 in three centers. Total and viable tumors were evaluated per patient at last follow-up after treatment. Response and progression-free survival (PFS) were assessed with (modified) response evaluation criteria in solid tumors (RECIST v.1.1 and mRECIST). Change in Numerical Rating Scale (NRS) pain and 36-item Short Form Health Survey (SF-36) scores were compared. Treatment-related adverse events were recorded. RESULTS: The median initial tumor volume was 114 mL (IQR 314 mL). After MRgFUS, median total and viable tumor volume decreased to 51 mL (95% CI: 30-71 mL, n = 101, p < 0.0001) and 29 mL (95% CI: 17-57 mL, n = 88, p < 0.0001), respectively, at last follow-up (median: 15 months, 95% CI: 11-20 months). Based on total tumor measurements (RECIST), 86% (95% CI: 75-93%) had at least stable disease or better at last follow-up, but 50% (95% CI: 38-62%) of remaining viable nodules (mRECIST) progressed within the tumor. Median PFS was reached at 17 and 13 months for total and viable tumors, respectively. NRS decreased from 6 (IQR 3) to 3 (IQR 4) (p < 0.001). SF-36 scores improved (physical health (41 (IQR 15) to 46 (IQR 12); p = 0.05, and mental health (49 (IQR 17) to 53 (IQR 9); p = 0.02)). Complications occurred in 36%, most commonly 1st/2nd degree skin burns. CONCLUSION: MRgFUS reduced tumor volume, reduced pain, and improved quality of life in this series of 105 patients with extra-abdominal desmoid fibromatosis. CLINICAL RELEVANCE STATEMENT: Imaging-guided ablation is being increasingly used as an alternative to surgery, radiation, and medical therapy for the treatment of desmoid fibromatosis. MR-guided high-intensity focused ultrasound is an incisionless ablation technique that can be used to reduce tumor burden effectively and safely. KEY POINTS: • Desmoid fibromatosis was treated with MR-guided high-intensity focused ultrasound in 105 patients. • MR-guided focused ultrasound ablation reduced tumor volume and pain and improved quality of life. • MR-guided focused ultrasound is a treatment option for patients with extra-abdominal desmoid tumors.

Soft tissue tumor imaging in adults: European Society of Musculoskeletal Radiology-Guidelines 2023-overview, and primary local imaging: how and where?

OBJECTIVES: Early, accurate diagnosis is crucial for the prognosis of patients with soft tissue sarcomas. To this end, standardization of imaging algorithms, technical requirements, and reporting is therefore a prerequisite. Since the first European Society of Musculoskeletal Radiology (ESSR) consensus in 2015, technical achievements, further insights into specific entities, and the revised WHO-classification (2020) and AJCC staging system (2017) made an update necessary. The guidelines are intended to support radiologists in their decision-making and contribute to interdisciplinary tumor board discussions. MATERIALS AND METHODS: A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements were scored online by level of agreement (0 to 10) during two iterative rounds. Either "group consensus," "group agreement," or "lack of agreement" was achieved. RESULTS: Eight sections were defined that finally contained 145 statements with comments. Overall, group consensus was reached in 95.9%, and group agreement in 4.1%. This communication contains the first part consisting of the imaging algorithm for suspected soft tissue tumors, methods for local imaging, and the role of tumor centers. CONCLUSION: Ultrasound represents the initial triage imaging modality for accessible and small tumors. MRI is the modality of choice for the characterization and local staging of most soft tissue tumors. CT is indicated in special situations. In suspicious or likely malignant tumors, a specialist tumor center should be contacted for referral or teleradiologic second opinion. This should be done before performing a biopsy, without exception. CLINICAL RELEVANCE: The updated ESSR soft tissue tumor imaging guidelines aim to provide best practice expert consensus for standardized imaging, to support radiologists in their decision-making, and to improve examination comparability both in individual patients and in future studies on individualized strategies. KEY POINTS: • Ultrasound remains the best initial triage imaging modality for accessible and small suspected soft tissue tumors. • MRI is the modality of choice for the characterization and local staging of soft tissue tumors in most cases; CT is indicated in special situations. Suspicious or likely malignant tumors should undergo biopsy. • In patients with large, indeterminate or suspicious tumors, a tumor reference center should be contacted for referral or teleradiologic second opinion; this must be done before a biopsy.

The health-related quality of life of sarcoma patients treated with neoadjuvant versus adjuvant radiotherapy - Results of a multi-center observational study.

AIM: The sequence of radiotherapy and resection in patients with soft tissue sarcomas is usually discussed on an individual basis. Better understanding of potential differences of health-related quality of life (QoL) between patients undergoing adjuvant (ART) versus neoadjuvant radiotherapy (NART) is therefore helpful for clinical decision making. METHODS: Adult sarcoma patients from 39 hospitals completed the European Organisation for Research and Treatment of Cancer Quality of Life Core Questionnaire (EORTC QLQ-C30). Differences in global QoL, physical functioning, role functioning, fatigue, pain, and insomnia between ART versus NART were investigated with multivariate regression, adjusting for age, gender, chemotherapy, grading, stage, tumor location, recurrence/distant metastasis, sarcoma type, time since last treatment, and treatment status using validated thresholds. RESULTS: A total of 1110 patients participated. Of them, 340 had received radiotherapy (NART: n = 95, 28%; ART: n = 245, 72%). Global QoL was 59.3 on average after NART and 60.5 after ART (Badj = 1.0, p = 0.74). Physical functioning was 65.9 compared to 70.5 (Badj = 4.2; p = 0.16), role function 48.8 vs. 56.7 (Badj = 7.0, p = 0.08), fatigue 47.5 vs. 45.4 (Badj = -1.2; p = 0.71), pain 40.2 vs. 34.1 (Badj = -6.8; p = 0.08), and insomnia 33.7 vs. 41.6 (Badj = 5.5, p = 0.16). Among patients with NART, clinically relevant QoL impairments were less frequent 2 years after treatment compared to < 2 years thereafter (n = 6 vs. n = 4 on average). CONCLUSION: There is little evidence for QoL differences in most domains and overall QoL between the two irradiation groups. However, patients after NART might experience worse role functioning and pain but fewer problems with insomnia compared to patients after ART.

Tratamiento multidisciplinario de un sarcoma recurrente de la fosa isquiorrectal / A successful multidisciplinary approach to a recurrent ischiorectal fossa sarcoma

Los tumores de la fosa isquiorrectal son poco frecuentes, habitualmente descritos en reportes o series de casos. Estas lesiones son un reto terapéutico, requiriendo un estudio preoperatorio apropiado, además de discusión y manejo guiado por un comité multidisciplinario, que permiten lograr resultados óptimos tanto oncológicos como funcionales. Presentamos un caso de un hombre de 73 años con antecedentes de resección de un tumor glúteo izquierdo en otro centro 5 años antes. La biopsia fue compatible con un sarcoma epiteloideo (SE) de alto grado, con margen quirúrgico < 0,5 mm que requirió ampliación de los márgenes posteriormente. Además, se realizó radioterapia adyuvante. Al cuarto año de seguimiento el paciente desarrolla dolor e induración con retracción en relación a cicatriz quirúrgica, siendo objetivada una recidiva tumoral local. Luego de una discusión multidisciplinaria, se realizó una desfuncionalización con ileostomía en asa laparoscópica y resección tumoral con preservación del ano y del piso pélvico. El defecto fue cubierto por el equipo de cirugía plástica utilizando un colgajo perforante de la arteria glútea superior. La biopsia confirmó la recidiva tumoral y los márgenes quirúrgicos fueron negativos. El paciente es dado de alta a los 25 días postoperatorios por cuidados del colgajo, sin complicaciones. Al año de seguimiento el paciente no presenta recidiva tumoral, la ileostomía fue cerrada, y sus resultados funcionales en términos defecatorios y de la herida son buenos.

Ischiorectal fossa tumors are rare lesions, mostly described in case reports or case series. These lesions represent a diagnostic and therapeutic challenge. Hence, an appropriate preoperative study and multidisciplinary discussion are essential to achieve good oncologic and functional results. We report a case of a 73-year-old male operated on five years before in another health center due to the diagnosis of a left gluteal tumor. The lesion was excised, and biopsies confirmed a high-grade epithelioid sarcoma with a close margin, requiring a subsequent wider excision of the surgical margins. The patient received adjuvant radiotherapy. After four years of follow-up, the patient developed mild pain with skin retraction around the former incision. A local recurrence was diagnosed by imaging. In a multidisciplinary team meeting, a decision to resect the lesion with preservation of the anus and the pelvic floor was taken. The patient underwent a laparoscopic defunctioning loop ileostomy and a resection of the recurrent tumor in the ischiorectal fossa with preservation of the anal sphincter. The defect was covered utilizing a superior gluteal artery perforator flap and a partial gluteus maximus muscle rotation. The tumor was completely excised with negative margins. The patient was discharged without complications after 25 days due to flap management. After one year of follow-up, the patient is recurrence-free, and the ileostomy was closed.

Lipofibromatosis-like neural tumors: Report of a case and review of 73 reported cases.

Lipofibromatosis-like neural tumors (LPF-NTs) are a recently discovered group of spindle cell tumors defined by the presence of a lipofibromatosis-like pattern, CD34 and/or S100 reactivity, and frequent neurotrophic receptor tyrosine kinase 1 (NTRK1) gene rearrangements. As new cases emerge, the spectrum of features observed in LPF-NTs continues to evolve. Here we describe the case of an 11-year-old with LPF-NT with a dermatofibrosarcoma protuberans-like honeycomb pattern, CD34 and S100 co-expression, and an NTRK1 rearrangement. We also review the clinical and molecular features of the 73 cases of LPF-NT previously described in the literature.

The oncological outcomes of isolated limb perfusion and neo-adjuvant radiotherapy in soft tissue sarcoma patients - A nationwide multicenter study.

INTRODUCTION: Patients with locally extensive high-grade extremity soft tissue sarcomas (eSTS) are often presented in multidisciplinary teams to decide between ablative surgery (amputation) or limb-salvage surgery supplemented with either neo-adjuvant radiotherapy (RT) or induction isolated limb perfusion (ILP). In The Netherlands, ILP typically aims to reduce the size of tumors that would otherwise be considered irresectable, whereas neo-adjuvant RT aims mainly at improving local control and reducing morbidity of required marginal margins. This study presents a 15-year nationwide cohort to describe the oncological outcomes of both pre-operative treatment strategies. METHODS: All consecutive patients with locally extensive primary high-grade eSTS surgically treated between 2000 and 2015 at five tertiary sarcoma centers that received neo-adjuvant ILP or RT were included. 169 patients met the inclusion criteria (89 ILP, 80 RT). Median follow-up was 7.3 years. RESULTS: Limb salvage was achieved in 84% of cases in the ILP group (80% for patients with amputation indication) and 96% of cases in the RT group. 5-Year overall survival was 47% in the ILP group, 69% in the RT group. 5-Year local recurrence rate was 14% in the ILP group, 10% in the RT group. Distant metastasis rate was 55% in the ILP group, 36% in the RT group. CONCLUSION: We find oncological outcomes and limb salvage rates in line with existing literature for both treatment modalities. Whether the tumor was locally advanced with an indication for induction therapy to prevent amputation or morbid surgery appeared to be the main determinant in choosing between neo-adjuvant ILP or RT.

Primary Soft-Tissue Lymphomas: MRI Features Help Discriminate From Other Soft-Tissue Tumors.

OBJECTIVES: MRI presentation of extra-nodal soft-tissue lymphomas (STLs) is scarcely reported and lacks of comparison with other soft-tissue tumors (STTs) including sarcomas (STS). Yet, suggesting this diagnosis on MRI would considerably reduce diagnostic intervals. Our aim was to investigate if conventional MRI could discriminate STLs from other STTs. METHODS: MRIs of STL patients were compared with those of patients addressed to a sarcoma reference center for the diagnosis of a STT. MRI characteristics depicting the tumor (size, signal, habitats, shape, surrounding tissues) were reported. Uni- and multivariate associations with STL diagnosis were evaluated in the entire cohort, and in the subgroups of benign and malignant STTs patients. Diagnostic performances of MRI features combinations were tested. RESULTS: We included 39 patients with STLs (median age: 69 years) and 368 patients with other STTs (122 benign STTs and 246 STS; median age: 58 years). Six MRI features were independent predictors of STL compared to all other STTs: intermediate SI on T1-WI, homogeneous enhancement (without necrotic areas), no blood signal, no fibrotic signal, no peritumoral enhancement and lack of abnormal intra- and peritumoral vasculature (p-value range: <0.0001-0.0163). Their simultaneous presence had a sensitivity of 0.88 (0.71-0.96) and a specificity of 0.88 (0.84-0.91). Other relevant MRI features were: no fat signal to discriminate against STS (p = 0.0409), the infiltrative growth pattern and the vessel and nerve encasement to discriminate against benign STTs (p = 0.0016 and 0.0011, respectively). CONCLUSION: Our research demonstrates that conventional MRI can help discriminating STLs from other STTs. Indeed, radiologists can help suggesting the possible diagnosis of STL, which could speed-up the subsequent proper histopathological analysis in light of MRI findings.

Long-term disease stability with bicalutamide in a man with aggressive angiomyxoma: case report and state of art.

Aggressive angiomyxoma (AA) is a rare mesenchymal neoplasm, which is commonly diagnosed in females and located in the perineal and pelvic region. Tissue specimens of AA patients often show positivity for estrogen (ER) and progesterone receptors (PgR), while some cases of androgen receptor (AR) positivity have been reported in males. When feasible, surgical excision represent the most effective treatment of AA; however, when experiencing advanced or recurrent disease, local disease control could be achieved with systemic hormonal treatment. To date, evidence regarding AA management in male patients is scarce, and only a few cases have been reported in literature. Hereby, we describe the case of a 59-year-old-man suffering from perineal AA with positivity for androgen receptors (AR) showing a long-lasting disease stability during the treatment with an AR-blocking drug (bicalutamide). A literature review regarding the state of art of AA management with a particular look to male patients is also provided.

Intravascular Myopericytoma: A Case Report.

Myopericytoma is a rare tumor that arises from perivascular myoid cells. Intravascular myopericytoma is an exceptionally rare subtype with a small number of cases reported. Here, we describe the case of a 31-year-old woman who presented with a lump on the dorsum of the right foot for nine months. Imaging indicated that the lesion is in close proximity to the dorsalis pedis vessels. Following surgical excision, the histological analysis revealed a benign neoplasm arising within a vein wall with features of vascular and pericytic differentiation. When using immunohistochemistry, the blood vessels were highlighted by the cluster of differentiation (CD) 31 and smooth muscle actin (SMA) with negative staining for pancytokeratins. These features led to the diagnosis of intravascular myopericytoma.

Lipoma gigante: tratamento cirúrgico / Giant lipoma: surgical treatment

Introdução: Lipomas gigantes (>1000g), embora raros, têm importância médica relevante, pois podem acometer qualquer região do corpo e ser diagnosticados em fases avançadas, nas quais há comprometimento funcional. Eles também podem ser confundidos com neoplasias malignas de tecidos moles. Ademais, a história natural de surgimento e evolução de lipomas gigantes ainda não é exatamente conhecida, o que justifica a realização de estudos adicionais. O objetivo do corrente estudo é apresentar os resultados do tratamento cirúrgico de um caso de lipoma gigante. Relato de Caso: Relato de caso ocorrido no serviço de cirurgia plástica do Hospital Roberto Santos em Salvador, Bahia, no ano de 2016. Homem de 62 anos, lavrador, 1,80m de altura, 74kg, com tumoração dorsal de 35cm de diâmetro, avaliado por meio de história clínica e exame de tomografia computadorizada e submetido a excisão elíptica e fechamento em plástica em W. Não houve complicações pós-operatórias. A histopatologia confirmou o diagnóstico de lipoma gigante (2881g). Os resultados pós-cirúrgicos foram considerados excelentes pelo paciente e equipe cirúrgica. Conclusão: O lipoma gigante foi removido satisfatoriamente sem complicações, com excelentes resultados funcionais e estéticos.

Introduction: Giant lipomas (>1000g), although rare, have relevant medical importance, as they can affect any region of the body and are diagnosed in advanced stages, in which there is functional impairment. They can also be confused with malignant soft tissue neoplasms. Furthermore, the natural history of the emergence and evolution of giant lipomas is still not exactly known, which justifies further studies. The current study aims to present the results of the surgical treatment of a case of giant lipoma. Case Report: Case report that occurred in the plastic surgery service of the Roberto Santos Hospital in Salvador, Bahia, in the year 2016. A 62-year-old male farmer, 1.80 m tall, 74 kg, with a dorsal tumor measuring 35 cm in diameter, evaluated through clinical history and computed tomography examination and submitted to elliptical excision and plastic closure in W. There were no postoperative complications. Histopathology confirmed the diagnosis of giant lipoma (2881g). Post-surgical results were considered excellent by the patient and surgical team. Conclusion: The giant lipoma was satisfactorily removed without complications, with excellent functional and aesthetic results.

Fibrous hamartoma of infancy with sarcomatous transformation: an unusual morphology.

Background: Fibrous hamartoma of infancy (FHI) is a rare soft tissue lesion arising as a subcutaneous mass involving the axilla, trunk, and upper arm in infants and children <2yrs. Sarcomatous transformation in FHI is described in anecdotal cases in the literature. Case Report: We describe one such example arising as a mass in the lower back in a 3-month-old infant. On histology, the tumor contained classic triphasic morphology; however, brisk mitotic activity noted at multiple foci was diagnostically challenging to categorize. The tumor was evaluated for ETV6-NTRK3 fusion to exclude other common differentials. Conclusion: While FHI may be frequently encountered in infants, rare sarcomatous transformation are known to occur and merits special attention as it can be misdiagnosed. Also, a close follow-up is warranted as the lesion is known to recur locally.

Leiomioma primario de páncreas en una gestante: presentación de caso / Primary pancreatic leimyoma in a pregnant woman: case report

RESUMEN Introducción: Los tumores pancreáticos en el embarazo son muy raros, el diagnóstico y tratamiento en este grupo de pacientes es complejo. Objetivo: Presentar el primer caso de un leiomioma primario del páncreas en una gestante. Caso clínico: Embarazada de 26 años de edad, sin antecedentes relevantes. Primigesta, que se encontraba cursando la semana 13 de gestación. Durante una evaluación ecográfica de rutina, se le detecta una tumoración en la glándula pancreática. Se remitió a la consulta multidisciplinaria de atención a la materna y en conjunto deciden realizar la interrupción voluntaria del embarazo. Luego la paciente fue remitida a la consulta de la especialidadde Cirugía General. Al recibir a la misma, se quejaba de dolor en epigastrio e hipocondrio izquierdo, además de hipo ocasional. Al examen físico se encontró una tumoración palpable en epigastrio. Se realizaron exámenes analíticos básicos sin encontrarse alteraciones, en los estudios de imagen realizados, ecografía abdominal y tomografía contrastada de abdomen se demostró una tumoración en el cuerpo y cola del páncreas. Se planificó tratamiento quirúrgico electivo, se realizó pancreatectomía distal con esplenectomía, por invasión del estómago, se complementó con gastrectomía subtotal. La paciente evoluciona sin complicaciones. La biopsia informó un tumor mesenquimal benigno primario de páncreas, tipo leiomioma, bien encapsulado. Conclusiones: Se presenta el primer caso de un leiomioma primario del páncreas en una gestante. Los tumores pancreáticos en embarazadas son enfemedades raras, el manejo por un equipo multidisciplinario es la mejor forma de obtener resultados satisfactorios para la paciente.

ABSTRACT Introduction: Pancreatic tumors during pregnancy are very rare, diagnosis and treatment are always difficult. Objective: To present the first case of a primary pancreatic leiomyoma in a pregnant woman. Case report: A 26 years old primiparous pregnant is reported, with no relevant backgrounds. She was in her first trimesters of pregnancy. Diagnosed with a pancreatic tumor during a routine evaluation. She was referred to a multidisciplinary consult, deciding the voluntary interruption of pregnancy, then she is evaluated by the General Surgery specialty clinic for complaining of epigastric pain and hiccup. On physical examination an epigastric tumor was found. Auxiliary exams were normal. Imagenologic studies confirm a tumor in the pancreatic body and tail. Surgical treatment was scheduled, distal pancreatectomy with splenectomy, due to invasion of gastric wall subtotal distal gastrectomy was performed. Patient evolution without complications. Biopsy reported a well capsulated, leiomyoma type, primary mesenchymal pancreatic tumor. Conclusions: The first case of a primary pancreatic leiomyoma in a pregnant woman is presented. Pancreatic tumors during pregnancy are rare. Multidisciplinary approach is the best way to improve results.

Fibrous hamartoma of infancy with sarcomatous transformation: an unusual morphology

ABSTRACT Background Fibrous hamartoma of infancy (FHI) is a rare soft tissue lesion arising as a subcutaneous mass involving the axilla, trunk, and upper arm in infants and children <2yrs. Sarcomatous transformation in FHI is described in anecdotal cases in the literature. Case Report We describe one such example arising as a mass in the lower back in a 3-month-old infant. On histology, the tumor contained classic triphasic morphology; however, brisk mitotic activity noted at multiple foci was diagnostically challenging to categorize. The tumor was evaluated for ETV6-NTRK3 fusion to exclude other common differentials. Conclusion While FHI may be frequently encountered in infants, rare sarcomatous transformation are known to occur and merits special attention as it can be misdiagnosed. Also, a close follow-up is warranted as the lesion is known to recur locally.

MRI-histopathological correlation in paediatric conventional central chondrosarcoma: a report of 17 cases.

OBJECTIVE: To describe the MRI features of paediatric conventional central chondrosarcoma (CC-CS) and correlate with histological grade. MATERIALS AND METHODS: A retrospective review of children/adolescents with histologically confirmed CC-CS. Data collected included age, sex, skeletal location, and histology from needle biopsy or resection, which was classified as atypical cartilaginous tumours/grade 1 CS (ACT/Gd 1 CS), high-grade chondrosarcoma (HGCS), and dedifferentiated chondrosarcoma (DD-CS). MRI studies were reviewed independently by 2 radiologists blinded to the histology grade, who graded the tumours as ACT/Gd 1 CS, HGCS, and DD-CS based on MRI features. RESULTS: The study included 7 males and 10 females with mean age 13.9 years (range 6-18 years). Tumours were located in the femur (n = 6), humerus (n = 3), tibia, ilium, scapula, and ulna (n = 1 each), and the small bones of the hands or feet (n = 4). Final histology grade was ACT/Gd 1 CS in 15 cases and HGCS in 2 (both grade 1 CS with focal transition to grade 2), 15 based on surgical specimens, 1 based on open biopsy, and 1 on needle biopsy alone. Predicted MRI grade for the 2 readers was ACT/Gd 1 CS in 11 cases each and HGCS in 6 cases each, indicating a mismatch between predicted MRI grade and histological grade in 8 (47%) cases (4 cases with one reader mismatch and 4 cases with both). CONCLUSIONS: MRI findings in paediatric CC-CS may be misleading, showing features suggestive of HGCS 7 of 17 (41.2%) of cases. This should be taken into consideration when planning surgical treatment.

Epithelioid Sarcoma of the Peripheral Nerve: Clinicopathologic Series of Three Cases and Literature Review.

OBJECTIVES: Epithelioid sarcoma (ES) rarely arises in the nerve. To increase our understanding of this unusual tumor originating in the nerve, we describe the features of three cases and review the literature. METHODS: Clinical data, imaging, pathology, treatment, and follow-up are detailed. A systematic literature review was conducted. RESULTS: Two patients were male and one female; the median age was 24 years. The patients had neurologic symptoms, and the tumors arose in large nerves and ranged from 2.4 to 5.8 cm. The tumors were avid on positron emission tomography-computed tomography and showed increased signal intensity on T2-weighted magnetic resonance imaging. Centered in the nerve, the tumors grew with an infiltrative pattern and encased the nerve fascicles. All were treated with wide resection, and adjuvant treatment included combinations of chemotherapy and radiation. One recurred, and the limb was amputated. Metastases were documented to lymph nodes, lung, pleura, and skin. One patient died of disease after 54 months. Literature review including our cases showed that tumors stained with pancytokeratin (9/9), EMA (4/4), and CD34 (7/7); there was loss of INI1 in all six cases tested. CONCLUSIONS: ES rarely arises in the peripheral nerve, and its infiltrative nature often requires morbid surgery. The differential includes a variety of benign and malignant epithelioid neoplasms.

Fine-needle aspiration biopsy for the diagnosis of bone and soft tissue lesions: a systematic review and meta-analysis.

INTRODUCTION: The workup of musculoskeletal (MSK) lesions utilizes a range of diagnostic tests including incisional biopsy, core needle biopsy, and fine-needle aspiration (FNA). FNA is the most cost-effective and least invasive biopsy method, but variation in its reported diagnostic performance has constrained its use for MSK lesions. Herein, we undertake a meta-analysis to clarify the diagnostic performance of FNA for bone and soft tissue lesions. MATERIALS AND METHODS: A systematic search was run in MEDLINE, EMBASE, and CINAHL. Included studies were aggregated for pooled estimates of adequacy, accuracy, and sensitivity/specificity for all MSK lesions as well as bone and soft tissue independently. Analysis of heterogeneity and risk of bias were assessed across studies. Covariate subgroup analyses were attempted to investigate potential influences on diagnostic accuracy. RESULTS: Twenty-five articles met inclusion criteria, representing 4604 FNAs. Adequacy was 92.3% (range: 59.2%-98.0%, S = 9.4%), and sensitivity/specificity for the nature (malignant or benign) of the lesion was 95.6% (95% CI: 94.5%-96.5%) and 96.9% (95% CI: 95.9%-97.7%). FNA was 75.8% accurate (range: 42.5%-99.3%, S = 17.3%) for definitive diagnosis. FNA provides higher accuracy for benign versus malignant nature in bone lesions but achieves a definitive diagnosis more frequently in soft tissue lesions. CONCLUSIONS: The results of this meta-analysis support the expanded use of FNA in the diagnostic workup of bone and soft tissue lesions, particularly in light of a sensitivity and specificity comparable to incisional and core needle biopsy.

[Multiple recurrent retroperitoneal liposarcoma in a 66-year-old man]. / Multipel rezidivierendes retroperitoneales Liposarkom bei einem 66-jährigen Patienten.

In this article, the authors present the case of a 66-year-old man who was diagnosed with the first recurrence of his retroperitoneal liposarcoma 7 years after initial diagnosis. In the following 10 years, he needed a total of eight operations, chemotherapy, and radiotherapy because of another seven recurrences. This is the first report on a patient with eight recurrences of a retroperitoneal liposarcoma being in a relatively good general condition even 17 years after initial diagnosis.

Distinguishing bone and soft tissue infections mimicking sarcomas requires multimodal multidisciplinary team assessment.

INTRODUCTION: The aims of this study were to report the presenting characteristics and identify how best to distinguish bone and soft-tissue infections that mimic sarcomas. MATERIALS AND METHODS: A total of 238 (211 osteomyelitis and 27 soft-tissue infections) patients referred to a tertiary sarcoma multidisciplinary team with suspected sarcoma who were ultimately diagnosed with a bone or soft tissue infection were included. Data from a prospectively collated database was analysed retrospectively. RESULTS: Of all possible bone and soft-tissue sarcoma referrals, a diagnosis of infection was made in 2.1% and 0.7%, respectively. Median age was 18 years in the osteomyelitis group and 46 years in the soft-tissue infection group. In the osteomyelitis group, the most common presenting features were pain (85.8%) and swelling (32.7%). In the soft-tissue infection group, the most common clinical features were swelling (96.3%) and pain (70.4%). Those in the soft-tissue group were more likely to have raised inflammatory markers. Radiological investigations were unable to discern between tumour or infection in 59.7% of osteomyelitis and 81.5% of soft-tissue infection cases. No organism was identified in 64.9% of those who had a percutaneous biopsy culture. CONCLUSIONS: This study has highlighted that infection is frequently clinically indistinguishable from sarcoma and remains a principle non-neoplastic differential diagnosis. When patients are investigated for suspected sarcoma, infections can be missed due to falsely negative radiological investigations and percutaneous biopsy. As no single clinical, biochemical or radiological feature or investigation can be relied upon for diagnosis, clinicians should have a low threshold for tissue biopsy and discussion in a sarcoma multidisciplinary team meeting.