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Background: Clear cell sarcoma (CCS) and alveolar soft part sarcoma (ASPS) are rare, and standard systemic therapy is not established except for sunitinib in ASPS. It is known that CCS and ASPS have a common biological feature of melanoma and Xp11.2/TFE3 translocation renal cell carcinoma, and immune‐checkpoint inhibitors (ICIs) are effective in these tumors. The authors conducted a phase 2 trial to evaluate the efficacy and safety of nivolumab for CCS and ASPS. Methods: The number of patients expected to be enrolled was 15–25 and was determined based on the Bayesian design. The primary end point was the confirmed objective response rate (ORR) according to the central review and the secondary end points included ORR, progression‐free survival (PFS), overall survival (OS), and safety. Results: A total of 26 patients (CCS, 12; ASPS, 14) were enrolled. Efficacy and safety were analyzed on 25 and 26 patients, respectively. The minimum number of responses required for a positive conclusion regarding the efficacy was four. However, only one patient (4.0%) with ASPS had a partial response. Complete response, stable disease, progression disease, and not evaluable were 0%, 60%, 32%, and 4.0%, respectively. Adverse events of grade 3 or 4 occurred in 57.7% (15 of 26). The median PFS was 4.9 months (95% confidence interval [CI], 3.7–8.6 months) and the median OS was 15.8 months (95% CI, 8.2–not reached). Conclusions: The primary end point of the ORR was not met for CCS and ASPS on the central review. Further studies are needed to evaluate ICIs in patients with ASPS. This study evaluated the efficacy and safety of nivolumab monotherapy for patients with clear cell sarcoma and alveolar soft part sarcoma in a single‐arm phase 2 trial. The results showed no clinical efficacy among patients with clear cell sarcoma, whereas further investigation was considered necessary among patients with alveolar soft part sarcoma. [ABSTRACT FROM AUTHOR]

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Intracranial teratomas constitute the majority of congenital Central Nervous System (CNS) germ cell tumours. Pure mature or immature teratomas present with giant intracranial masses that cause irreversible brain damage and impair the quality of life. Two such cases are reported here: the first involves a four-month-old female infant with a large right hemispheric lesion, and the second involves a three-month-old female infant with a similar large right hemispheric space-occupying lesion. Both underwent craniotomy but ultimately succumbed to death within a few days after the operation. Immature teratomas of the ovaries are the second most common malignant germ cell tumour following dysgerminoma, with good prognosis and excellent overall survival rates. One such case is presented here, involving a 16-year-old adolescent female with a history of irregular and painful menstruation presenting with a large abdomino-pelvic mass that was determined to be of ovarian origin through imaging studies. Alveolar Soft Part Sarcoma (ASPS) is a rare soft-tissue sarcoma with a poor prognosis, demonstrated in a 17-year-old girl who presented with a painless left thigh mass that was clinically misdiagnosed as a benign intramuscular lipoma. Another case involves a 14-year-old boy with Ewing sarcoma of the ring finger, an extremely rare hand tumour with a high potential for misdiagnosis and delayed treatment, accompanied by a focus of pulmonary metastasis. The final case involves a poorly differentiated carcinoma of the Ileum in a 17-year-old girl who was eventually lost to follow-up checkups.

Alveolar soft part sarcoma (ASPS) is a rare malignant soft tissue tumor characterized by painless, non-functional, and slow-growing masses. Its rarity and deceptive growth pattern can make early diagnosis and timely management challenging in clinical practice. We report a case of ASPS in a 37-year-old male who presented with a five-year-old, initially undiagnosed swelling in his right axilla. Subsequently, the patient experienced intermittent dizziness, dysgraphia, and metamorphopsia. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a mass in the right axilla, multiple lung nodules, and a left parieto-occipital occupying lesion. Craniotomy confirmed metastatic ASPS in the intracranial region. Subsequent resection of the right axillary mass identified it as the primary tumor site. This article presents a literature review of ASPS, summarizing its CT, MRI, and clinical manifestations. We aim to enhance physician understanding of ASPS, providing insights for early diagnosis and treatment to improve long-term patient survival rates.

Background: Primary uterine alveolar soft part sarcoma (ASPS) is a rare, indolent mesenchymal malignancy with less than 40 patients documented in the literature. Case: We report an example of ASPS in a 61-year-old postmenopausal woman. Macroscopically, the uterus showed multiple nodular masses. Microscopic examination revealed tumor arranged in nests and alveolar pattern. The tumor cells were moderately to markedly pleomorphic, epithelioid to polygonal, with eccentrically placed nuclei, vesicular chromatin, prominent macro-nucleoli, and moderate to abundant eosinophilic cytoplasm. PAS-positive and diastase-resistant intracytoplasmic crystals were also seen in some tumor cells. On immunohistochemistry, the tumor cells showed diffuse positivity for vimentin and nuclear positivity for TFE3, a surrogate marker for ASPS. These were negative for SMA, desmin, CD10, h-caldesmon, cyclin D1, EMA, Melan A, and CD34. SMARCB1 expression was retained. Based on the histopathology and IHC, a final diagnosis of uterine ASPS was rendered. Conclusions: Knowledge of the characteristic histopathologic and immunohistochemical features can help accurately diagnose such rare tumors. Knowledge of the characteristic histopathologic and immunohistochemical features can help accurately diagnose such rare sarcoma in an uncommon site with an unusual age. [ABSTRACT FROM AUTHOR]

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Abstract Objective To investigate the correlation between MRI findings and histological features for preoperative prediction of histological grading and Ki-67 expression level in alveolar soft part sarcoma (ASPS). Methods A retrospective analysis was conducted on 63 ASPS patients (Jan 2017–May 2023). All patients underwent 3.0-T MRI examinations, including conventional sequences, dynamic contrast-enhanced scans with time-intensity curve analysis, and diffusion-weighted imaging with apparent diffusion coefficient (ADC) measurements. Patients were divided into low-grade (histological Grade I) and high-grade (histological Grade II/III) groups based on pathology. Immunohistochemistry was used to assess Ki-67 expression levels in ASPS. Statistical analysis included chi-square tests, Wilcoxon rank-sum test, binary logistic regression analysis, Spearman correlation analysis, and receiver operating characteristic curve analysis of various observational data. Results There were 29 low-grade and 34 high-grade patients (26 males and 37 females) and a wide age range (5–68 years). Distant metastasis, tumor enhancement characteristics, and ADC values were independent predictors of high-grade ASPS. High-grade ASPS had lower ADC values (p = 0.002), with an area under the curve (AUC), sensitivity, and specificity of 0.723, 79.4%, and 58.6%, respectively, for high-grade prediction. There was a negative correlation between ADC values and Ki-67 expression (r = −0.526; p

Objective: Alveolar soft part sarcoma (ASPS) is characterized by distinctive histomorphology of variably discohesive epithelioid cells arranged in nests and translocation of t(x;17) (p11.2;q25) resulting in ASPSCR1-TFE3 fusion. The aim of the present study is to review the clinical, histopathological, and immunohistochemical profile of ASPS with a focus on unusual histological features. Material and Method: The present study is retrospective and descriptive. All cases with a diagnosis of ASPS were retrieved with clinical and radiology details. Results: 22 patients of ASPS were identified. The most common site was the lower extremity and the size range was 3-22 cm. 54.5% of the patients had metastasis, with the lung as the most common site. Metastasis preceded detection of primary tumour in two cases. All cases showed similar histopathology of monomorphic epithelioid cells arranged in nests encircled by sinusoidal vasculature. Architecturally, the organoid pattern (81.8%) was followed by the alveolar pattern. 68.2% of the cases showed apple bite nuclei as the predominant nuclear feature. Rare nuclear features included binucleation (n=13), multinucleation (n=8), pleomorphism (n=4), nuclear grooves in three cases and intranuclear inclusion in one case, mitosis (n=5), and focal necrosis (n=6). All cases were positive for TFE3 and negative for AE1/AE3, EMA, HMB45, PAX8, MyoD1, SMA, synaptophysin, and chromogranin. Only two cases showed focal S100 positivity while one showed focal desmin positivity. Conclusion: Diffuse strong nuclear TFE3 positivity is sensitive for ASPS in an appropriate clinicoradiological context. Due to the high propensity for early metastasis, complete metastatic work-up and long term follow up is recommended.

Abstract Background Alveolar soft part sarcoma is a rare tumour of soft tissues, mostly localized in muscles or deep soft tissues of the extremities. In rare occasions, this tumour develops in deep tissues of the abdomen or pelvis. Case presentation In this case report, we described the case of a 46 year old man who developed a primary splenic alveolar soft part sarcoma. The tumour displayed typical morphological alveolar aspect, as well as immunohistochemical profile notably TFE3 nuclear staining. Detection of ASPSCR1 Exon 7::TFE3 Exon 6 fusion transcript in molecular biology and TFE3 rearrangement in FISH confirmed the diagnosis. Conclusion We described the first case of primary splenic alveolar soft part sarcoma, which questions once again the cell of origin of this rare tumour.

Objective: To investigate the correlation between MRI findings and histological features for preoperative prediction of histological grading and Ki-67 expression level in alveolar soft part sarcoma (ASPS). Methods: A retrospective analysis was conducted on 63 ASPS patients (Jan 2017–May 2023). All patients underwent 3.0-T MRI examinations, including conventional sequences, dynamic contrast-enhanced scans with time-intensity curve analysis, and diffusion-weighted imaging with apparent diffusion coefficient (ADC) measurements. Patients were divided into low-grade (histological Grade I) and high-grade (histological Grade II/III) groups based on pathology. Immunohistochemistry was used to assess Ki-67 expression levels in ASPS. Statistical analysis included chi-square tests, Wilcoxon rank-sum test, binary logistic regression analysis, Spearman correlation analysis, and receiver operating characteristic curve analysis of various observational data. Results: There were 29 low-grade and 34 high-grade patients (26 males and 37 females) and a wide age range (5–68 years). Distant metastasis, tumor enhancement characteristics, and ADC values were independent predictors of high-grade ASPS. High-grade ASPS had lower ADC values (p = 0.002), with an area under the curve (AUC), sensitivity, and specificity of 0.723, 79.4%, and 58.6%, respectively, for high-grade prediction. There was a negative correlation between ADC values and Ki-67 expression (r = −0.526; p < 0.001). When the cut-off value of ADC was 0.997 × 10−3 mm²/s, the AUC, sensitivity, and specificity for predicting high Ki-67 expression were 0.805, 65.6%, and 83.9%, respectively. Conclusion: Qualitative and quantitative MRI parameters are valuable for predicting histological grading and Ki-67 expression levels in ASPS. Critical relevance statement: This study will help provide a more nuanced understanding of ASPS and guide personalized treatment strategies. Key Points: There is limited research on assessing ASPS prognosis through MRI. Metastasis, enhancement, and ADC correlated with histological grade; ADC related to Ki-67 expression. MRI provides clinicians with valuable information on ASPS grading and proliferation activity. [ABSTRACT FROM AUTHOR]

Objective: Alveolar soft part sarcoma (ASPS) is characterized by distinctive histomorphology of variably discohesive epithelioid cells arranged in nests and translocation of t(x;17) (p11.2;q25) resulting in ASPSCR1-TFE3 fusion. The aim of the present study is to review the clinical, histopathological, and immunohistochemical profile of ASPS with a focus on unusual histological features. Material and Methods: The present study is retrospective and descriptive. All cases with a diagnosis of ASPS were retrieved with clinical and radiology details. Results: 22 patients of ASPS were identified. The most common site was the lower extremity and the size range was 3-22 cm. 54.5% of the patients had metastasis, with the lung as the most common site. Metastasis preceded detection of primary tumour in two cases. All cases showed similar histopathology of monomorphic epithelioid cells arranged in nests encircled by sinusoidal vasculature. Architecturally, the organoid pattern (81.8%) was followed by the alveolar pattern. 68.2% of the cases showed apple bite nuclei as the predominant nuclear feature. Rare nuclear features included binucleation (n=13), multinucleation (n=8), pleomorphism (n=4), nuclear grooves in three cases and intranuclear inclusion in one case, mitosis (n=5), and focal necrosis (n=6). All cases were positive for TFE3 and negative for AE1/AE3, EMA, HMB45, PAX8, MyoD1, SMA, synaptophysin, and chromogranin. Only two cases showed focal S100 positivity while one showed focal desmin positivity. Conclusion: Diffuse strong nuclear TFE3 positivity is sensitive for ASPS in an appropriate clinicoradiological context. Due to the high propensity for early metastasis, complete metastatic work-up and long term follow up is recommended. [ABSTRACT FROM AUTHOR]

Background: Alveolar soft part sarcoma is a rare tumour of soft tissues, mostly localized in muscles or deep soft tissues of the extremities. In rare occasions, this tumour develops in deep tissues of the abdomen or pelvis. Case presentation: In this case report, we described the case of a 46 year old man who developed a primary splenic alveolar soft part sarcoma. The tumour displayed typical morphological alveolar aspect, as well as immunohistochemical profile notably TFE3 nuclear staining. Detection of ASPSCR1 Exon 7::TFE3 Exon 6 fusion transcript in molecular biology and TFE3 rearrangement in FISH confirmed the diagnosis. Conclusion: We described the first case of primary splenic alveolar soft part sarcoma, which questions once again the cell of origin of this rare tumour. [ABSTRACT FROM AUTHOR]

Uterine cervical sarcomas are extremely rare tumors. Patients may present with vaginal bleeding, mass protruding from vagina, and vaginal discharge. Surgical treatment as well as chemotherapy or radiotherapy can be utilized. Fertility-sparing surgery can be performed since most patients are in their reproductive age. Data of four patients with a mean age of 17.7 years are discussed. Fertility-sparing surgery was performed in all of these patients and adjuvant chemotheraphy was needed in two of them. Subtype of sarcomas were embryonal rhabdomyosarcoma in three patients, and alveolar soft part sarcoma in one patient. Three patients are being followed as disease-free, one case died. [ABSTRACT FROM AUTHOR]

Xingtao Long,1 Qingming Jiang,2 Rengui Li,1 Dong Wang,1 Dongling Zou1 1Department of Gynaecological Oncology, Chongqing University Cancer Hospital, Chongqing, People’s Republic of China; 2Department of Pathology, Chongqing University Cancer Hospital, Chongqing, People’s Republic of ChinaCorrespondence: Dongling Zou, Department of Gynaecological Oncology, Chongqing University Cancer Hospital, 181 Hanyu Road, Shapingba District, Chongqing, 400000, People’s Republic of China, Tel +8613657690699, Fax +8602365075612, Email cqzl_zdl@163.comIntroduction: Alveolar soft part sarcoma (ASPS) is a rare and distinct subtype of soft tissue sarcoma. This study aims to describe the unique presentation of ASPS in the female genital tract.Methods: Prognostic factors for cancer-specific overall survival (CSS) were evaluated using multivariate analyses.Results: In our case series, we identified a novel TFE3-PRCC gene fusion in a 24-year-old unmarried patient with cervical ASPS who underwent fertility-sparing surgery and remained recurrence-free for 41 months. The other two patients underwent radical hysterectomy and bilateral salpingo-oophorectomy. At the time of writing, the two patients had been disease-free for 49 and 71 months, fluorescence in situ hybridization showed break-apart signals for the ASPL-TFE3 gene. Among the 55 cases with available information from the PubMed/Medline database, most presented with localized disease, and at the last follow-up, all patients were alive and 45 patients showed no evidence of disease. The 5-year CSS rate in the female genital tract cohort from SEER database was 86.2%. Multivariate analysis revealed that older age was associated with a 1.042-fold increased risk of cancer-specific mortality (HR=1.042, 95% CI 1.022– 1.063, P < 0.001), involvement of soft tissue including the heart was associated with a 4.786-fold higher risk (HR=4.7868, 95% CI 1.681– 13.623, P= 0.003), and regional infiltration and distant metastasis were associated with approximately 8.6-fold and 18-fold higher risk of cancer-specific mortality compared to local disease, respectively (HR=8.652, 95% CI 2.529– 29.63, P = 0.001; HR=18.366, 95% CI 6.153– 54.817, P< 0.001). Patients who underwent radical excision did not show reduced cancer-specific mortality compared to those who underwent local excision (HR=0.492, 95% CI 0.224– 1.081, P = 0.078).Discussion: Previously unrecognized genetic diversity exists in ASPS. Patients with ASPS in the female genital tract have the lowest likelihood of presenting with a distant disease and are associated with a more favorable survival outcome.Keywords: ASPSCR1, TFE3, alveolar soft part sarcoma, fusion

Abstract Objective This study aimed to investigate the clinicopathological features and prognostic indicators of alveolar soft part sarcoma (ASPS). Methods The characteristics of 26 ASPS patients diagnosed at our hospital between January 2011 and January 2019 were retrospectively analysed. Results The data for 12 male and 14 female patients, with a median age of 27.5 years, were assessed. The clinical symptoms mainly included painless enlarged masses in deep soft tissues. ASPS had a characteristic pathological morphology. Twenty-four patients were positive for TFE3, and TFE3 gene rearrangement was detected in 12 patients. Among the 26 patients who completed follow-up, 14 had metastasis, 1 had local recurrence, and 7 died. Kaplan–Meier survival analysis revealed that prognosis was significantly correlated with sex, tumour size and metastasis (P

Aims: Mesenchymal neoplasms involving TFE3 gene fusions are diverse, mainly include alveolar soft part sarcoma (ASPS) that is characterised by ASPSCR1::TFE3 fusion, and a small subset of perivascular epithelioid cell tumours (PEComas) referred to as TFE3‐rearranged PEComa, that most frequently harbours SFPQ::TFE3 fusion. Historically, ASPS and TFE3‐rearranged PEComa are considered two distinctive entities despite their known morphological overlap. However, recent studies have suggested a potential histogenetic relationship between them, and several neoplasms that showed morphological features more closely fit PEComa rather than ASPS but harboured ASPSCR1::TFE3 fusion have been documented. In this study, we report three cases of PEComa with ASPSCR1::TFE3 fusion. Methods and results: Clinicopathological features were assessed and partner agnostic targeted next‐generation sequencing on clinically validated platforms were performed. The patients are two females and one male with age at presentation ranging from 21 to 51 years. All three tumours were located in the viscera (rectum, kidney and cervix). On a relatively limited follow‐up period (range = 9–15 months), all patients are alive without evidence of recurrent or metastatic disease. The neoplasms were composed of tight nested architecture of epithelioid clear cells separated by a delicate vascular network, two of which were associated with sheets of plump spindle cells, and none showed significant discohesive tumour morphology. Immunohistochemically, in addition to TFE3 protein, all three neoplasms demonstrated co‐expression of melan‐A and smooth muscle actin. RNA‐sequencing identified ASPSCR1::TFE3 fusion in all three cases that were confirmed by subsequent fluorescence in‐situ hybridisation analyses. Conclusions: Our study expands the molecular genetic spectrum of TFE3‐rearranged PEComa and further indicates its close relationship to ASPS. [ABSTRACT FROM AUTHOR]

Background Antimicrobial stewardship programs (ASPs) promote optimal antimicrobial use to prevent resistance, improve outcomes, and reduce costs. We explored how pediatric ASPs enact prospective audit and feedback (PAF) and preauthorization and characterized programs' perceptions of how these choices affected attainment of stewardship goals. Methods We conducted focus groups with US pediatric ASP practitioners, organized by predominant strategy: PAF, preauthorization, or a hybrid. We asked open-ended questions about organization, staffing, and operation of these strategies, as well as rationales for and perceived advantages and disadvantages of these choices. We used applied thematic analysis to analyze transcripts, organizing coded text into themes and categories. We formulated a conceptual model for how the design and performance of PAF and preauthorization affect stewardship goals and stewards' work experiences. Results Eighteen physicians and 14 pharmacists from 24 hospitals participated in five focus groups. Stewards described myriad advantages and limitations of PAF and preauthorization that support or detract from stewardship goals. For example, PAF uncovered institutional trends in antibiotic use and fostered relationship building but was time-consuming. Preauthorization efficiently reduced broad-spectrum antimicrobial use, yet offered limited educational opportunities. How these strategies facilitated or impeded appropriate antimicrobial use in turn affected stewards' professional satisfaction, creating a feedback loop that could reinforced positive or negative outcomes. Conclusions ASPs reported differing emphasis on and implementation of PAF and preauthorization. Each strategy entailed contrasting benefits and trade-offs for steward satisfaction and perceived efficacy, suggesting that a hybrid approach could enable ASPs to maximize strengths of each to mitigate drawbacks of the other. [ABSTRACT FROM AUTHOR]

Objective: Female genital alveolar soft part sarcoma (ASPS) is rare and has a favourable prognosis compared to ASPS from other sites. We reported our experience to manage a case with uterine corpus ASPS (UC ASPS) and conducted a literature review on prognosis of ASPS from different sites of female genital tract. Case report: This report represented a 33-year-old woman who had UC ASPS. She received tumor excision with uterine preservation and had the longest follow-up time (155 months) without recurrence in the literature. Conclusion: UC ASPS has better prognosis than ASPS from the uterine cervix, the low uterine segment, vulvovaginal area and perineum. We recommended conservative treatment for young women with UC ASPS.

Abstract Background Bone and soft tissue sarcomas are rare tumors and extremely rarely metastasize to the brain. Previous studies have examined the characteristics and poor prognostic factors in cases of sarcoma brain metastasis (BM). Due to the rarity of cases of BM from sarcoma, limited data exist concerning the prognostic factors and treatment strategies. Methods A retrospective single‐center study was performed on sarcoma patients with BM. The clinicopathological characteristics and treatment options for BM of sarcoma were investigated to identify predictive prognostic factors. Results Between 2006 and 2021, 32 patients treated for newly diagnosed BM at our hospital were retrieved among 3133 bone and soft tissue sarcoma patients via our database. The most common symptom was headache (34%), and the most common histological subtypes were alveolar soft part sarcoma (ASPS) and undifferentiated pleomorphic sarcoma (25%). Non‐ASPS (p = 0.022), presence of lung metastasis (p = 0.046), a short duration between initial metastasis, and the diagnosis of brain metastasis (p = 0.020), and the absence of stereotactic radiosurgery for BM (p = 0.0094) were significantly correlated with a poor prognosis. Conclusions In conclusion, the prognosis of patients with brain metastases of sarcomas is still dismal, but it is necessary to be aware of the factors associated with a relatively favorable prognosis and to select treatment options appropriately.

Abstract Background Alveolar soft part sarcoma (ASPS) is a rare kind of malignant soft tissue tumor with undefined differentiation, of which the incidence rate accounts for only 0.5–1.0% among all kinds of soft tissue tumors. An even rarer ASPS occurs in kidney. Case presentation Here we reported a case of a 7-year-old girl diagnosed with nephrogenic ASPS, regarding the analyses of the incidence, clinical manifestation, pathology and genetic diagnosis, in order to deepen the recognition of the disease. Conclusions ASPS is very rare, and tends to occur to young patients. It is very significant to precisely diagnose ASPS at an early stage, which will be the key point for the following treatment choices and prognosis.

Abstract Background Myositis ossificans circumscripta is a self-limiting, benign, ossifying lesion that can affect any type of soft tissue. It is most commonly found in muscles as a solitary lesion. A history of recent trauma has been reported in approximately 50% of cases. Clinically, MOC presents as a painful swelling, which rapidly increases in size. The pain and inflammatory symptoms spontaneously disappear after approximately 2–6 weeks, and the mass stabilizes or decreases. Radiologically, myositis ossificans circumscripta can be divided into two phases. The first is the acute phase, which is followed by the mature phase 2–6 weeks later. During the acute phase, the radiological aspect does not show any specific abnormality. In the mature phase, plain radiographs and computed tomography show blurred calcifications around a hypodense center. We describe here the first case of myositis ossificans circumscripta, with appropriate follow-up, occurring during sunitinib exposure. Case presentation We report a case of myositis ossificans circumscripta in a 34-year-old man (ethnicity unknown) receiving sunitinib for metastatic alveolar soft part sarcoma of the left thigh after surgery and radiotherapy. Four months after the first dose of sunitinib, the patient experienced painful swelling in the surgical scar area. Magnetic resonance imaging showed diffuse and marked edema of the anterior compartment of the thigh, without nodular lesions circumscribing a central core, and without bone signal abnormality. The increased visibility of the intermuscular fascia and convergence of normal muscle fibers (black hole effect), without the displacement seen in tumors, were suggestive of myositis. Therefore, antiangiogenic treatment was discontinued, and the symptoms rapidly resolved within a few days. Three weeks after the discontinuation of sunitinib, the inflammatory findings completely disappeared. Two months after the diagnosis of myositis ossificans circumscripta, plain radiographs and computed tomography showed an extensive calcified mass measuring > 12 cm. The continuation of favorable clinical outcomes was confirmed. Conclusions To the best of our knowledge, this is the first case of myositis ossificans circumscripta with appropriate follow-up occurring during sunitinib exposure. Owing to multimodal treatment of sarcoma, we cannot rule out the radiotherapy and surgery causality.

Background: Bone and soft tissue sarcomas are rare tumors and extremely rarely metastasize to the brain. Previous studies have examined the characteristics and poor prognostic factors in cases of sarcoma brain metastasis (BM). Due to the rarity of cases of BM from sarcoma, limited data exist concerning the prognostic factors and treatment strategies. Methods: A retrospective single‐center study was performed on sarcoma patients with BM. The clinicopathological characteristics and treatment options for BM of sarcoma were investigated to identify predictive prognostic factors. Results: Between 2006 and 2021, 32 patients treated for newly diagnosed BM at our hospital were retrieved among 3133 bone and soft tissue sarcoma patients via our database. The most common symptom was headache (34%), and the most common histological subtypes were alveolar soft part sarcoma (ASPS) and undifferentiated pleomorphic sarcoma (25%). Non‐ASPS (p = 0.022), presence of lung metastasis (p = 0.046), a short duration between initial metastasis, and the diagnosis of brain metastasis (p = 0.020), and the absence of stereotactic radiosurgery for BM (p = 0.0094) were significantly correlated with a poor prognosis. Conclusions: In conclusion, the prognosis of patients with brain metastases of sarcomas is still dismal, but it is necessary to be aware of the factors associated with a relatively favorable prognosis and to select treatment options appropriately. [ABSTRACT FROM AUTHOR]

Abstract Background Alveolar soft part sarcoma (ASPS) is a rare histological subtype of soft-tissue sarcoma, which remains refractory to conventional cytotoxic chemotherapy. We aimed to characterize ASPS and investigate whether the oncological outcome has improved over the past decade. Methods One hundred and twenty patients with newly diagnosed ASPS from 2006 to 2017, identified from the Bone and Soft-Tissue Tumor Registry in Japan, were analyzed retrospectively. Results The study cohort comprised 34 (28%) patients with localized ASPS and 86 (72%) with metastatic disease at presentation. The 5-year disease-specific survival (DSS) was 68% for all patients and 86% and 62% for localized and metastatic disease, respectively (p = 0.019). Metastasis at presentation was the only adverse prognostic factor for DSS (hazard ratio [HR]: 7.65; p = 0.048). Patients who were > 25 years (80%; p = 0.023), had deep-seated tumors (75%; p = 0.002), and tumors > 5 cm (5–10 cm, 81%; > 10 cm, 81%; p

Alveolar soft part sarcoma is a very rare malignant neoplasm of peripheral muscular, adipose or neural tissue. Its occurrence, as a primary intracranial tumour, is even rarer. To the best of our knowledge, only nine cases of primary intracranial alveolar soft part sarcoma exist in English scientific literature. We attempt to write a comprehensive review on this poorly understood intracranial malignancy, with no evident systemic lesions, such as in the case of our 22 years old patient. In addition to absent definitive proof of benefit of radiologic or chemotherapeutic management, we highlight the role of surgery as the primary treatment. Younger patients with this tumour may have a worse prognosis than elderly patients. Key words: alveolar soft part sarcoma, intracranial, headache, radiosurgery.

Background: Alveolar soft part sarcoma (ASPS) is a rare translocation-related soft tissue sarcoma, occurring mainly in the limbs and trunk in young adults and adolescents. ASPS is rarely seen in the head and neck and one fourth of those cases described are tongue primary. Given its nonspecific symptoms, clinical findings, and rarity in this location, lingual ASPS (L-ASPS) has been reported to be commonly misdiagnosed as various benign tumors, leading to adverse outcomes. Methods: We report a case of L-ASPS occurring in the oldest (78 years) female patient published to date and comprehensively review the literature from 1952 to 2022. Results: She presented with a slow-growing (2-year duration) tongue mass, measuring 3.5 cm on palpation. Intraoperative frozen section could not render the definitive diagnosis. The pathological findings of the tumor were characteristic of ASPS with eosinophilic polygonal cells in an organoid/nested pattern, rich sinusoidal capillaries, and TFE3 immunoreactivity, except for the strong diffuse aberrant cytoplasmic CD68 immunoexpression and absence of intracytoplasmic crystalline inclusions on PAS with diastase. After TFE3 gene rearrangement had been identified with fluorescent in-situ hybridization, reflex testing confirmed a rearrangement of TFE3 gene with the known fusion partner ASPSCR1. Conclusions: ASPS should be included in the differential diagnoses in cases of any slow-growing lingual masses (especially vascular ones) with non-specific clinical pictures, regardless of the patient's age. [ABSTRACT FROM AUTHOR]

Background: Alveolar soft part sarcoma (ASPS) is a rare kind of malignant soft tissue tumor with undefined differentiation, of which the incidence rate accounts for only 0.5–1.0% among all kinds of soft tissue tumors. An even rarer ASPS occurs in kidney. Case presentation: Here we reported a case of a 7-year-old girl diagnosed with nephrogenic ASPS, regarding the analyses of the incidence, clinical manifestation, pathology and genetic diagnosis, in order to deepen the recognition of the disease. Conclusions: ASPS is very rare, and tends to occur to young patients. It is very significant to precisely diagnose ASPS at an early stage, which will be the key point for the following treatment choices and prognosis. [ABSTRACT FROM AUTHOR]

Alveolar soft part sarcoma (ASPS) is a rare, highly vascular, deep soft tissue mesenchymal malignancy that is classically seen in the lower extremities of young adults. We reported a case of a 32-year-old young Chinese woman in Hong Kong with a biopsy-proven alveolar soft part sarcoma. The condition can be suggested by classical features using contrast-enhanced CT scans and MRIs or confirmed by image-guided biopsies. Early recognition of the condition is important due to its poor prognosis and lack of awareness. The mainstay of treatment for ASPS is complete surgical resection of the primary tumor and radiotherapy for microscopic residual disease at the primary site, or chemotherapy in special cases.

The ASPSCR1::TFE3 fusion gene, resulting from chromosomal translocation, is detected in alveolar soft part sarcoma (ASPS) and a subset of renal cell carcinomas (RCC). The ASPSCR1::TFE3 oncoprotein, functioning as an aberrant transcription factor, contributes to tumor development and progression by inappropriately upregulating target genes. Here, we identified insulin receptor substrate 2 (IRS-2), a cytoplasmic adaptor protein, as a novel transcriptional target of ASPSCR1::TFE3. Ectopic expression of ASPSCR1::TFE3 led to increased IRS-2 mRNA and protein levels. Chromatin immunoprecipitation and luciferase assays demonstrated that ASPSCR1::TFE3 bound to the IRS-2 promoter region and enhanced its transcription. Moreover, IRS-2 was highly expressed in the ASPSCR1::TFE3-positive RCC cell line FU-UR1, while small interfering RNA-mediated depletion of ASPSCR1::TFE3 markedly decreased IRS-2 mRNA and protein levels. Functionally, IRS-2 knockdown attenuated activation of the PI3K/AKT pathway and reduced proliferation, migration, invasion, adhesion, and clonogenicity in FU-UR1 cells. Pharmacological inhibition of IRS-2 also reduced AKT activation as well as cell viability, clonogenicity, migration, invasion, and adhesion. These findings suggest that IRS-2, regulated by ASPSCR1::TFE3, promotes tumor progression by activating PI3K/AKT signaling and enhancing the malignant phenotype. [ABSTRACT FROM AUTHOR]

Background: Myositis ossificans circumscripta is a self-limiting, benign, ossifying lesion that can affect any type of soft tissue. It is most commonly found in muscles as a solitary lesion. A history of recent trauma has been reported in approximately 50% of cases. Clinically, MOC presents as a painful swelling, which rapidly increases in size. The pain and inflammatory symptoms spontaneously disappear after approximately 2–6 weeks, and the mass stabilizes or decreases. Radiologically, myositis ossificans circumscripta can be divided into two phases. The first is the acute phase, which is followed by the mature phase 2–6 weeks later. During the acute phase, the radiological aspect does not show any specific abnormality. In the mature phase, plain radiographs and computed tomography show blurred calcifications around a hypodense center. We describe here the first case of myositis ossificans circumscripta, with appropriate follow-up, occurring during sunitinib exposure. Case presentation: We report a case of myositis ossificans circumscripta in a 34-year-old man (ethnicity unknown) receiving sunitinib for metastatic alveolar soft part sarcoma of the left thigh after surgery and radiotherapy. Four months after the first dose of sunitinib, the patient experienced painful swelling in the surgical scar area. Magnetic resonance imaging showed diffuse and marked edema of the anterior compartment of the thigh, without nodular lesions circumscribing a central core, and without bone signal abnormality. The increased visibility of the intermuscular fascia and convergence of normal muscle fibers (black hole effect), without the displacement seen in tumors, were suggestive of myositis. Therefore, antiangiogenic treatment was discontinued, and the symptoms rapidly resolved within a few days. Three weeks after the discontinuation of sunitinib, the inflammatory findings completely disappeared. Two months after the diagnosis of myositis ossificans circumscripta, plain radiographs and computed tomography showed an extensive calcified mass measuring > 12 cm. The continuation of favorable clinical outcomes was confirmed. Conclusions: To the best of our knowledge, this is the first case of myositis ossificans circumscripta with appropriate follow-up occurring during sunitinib exposure. Owing to multimodal treatment of sarcoma, we cannot rule out the radiotherapy and surgery causality. [ABSTRACT FROM AUTHOR]

Background: Alveolar soft part sarcoma (ASPS) is a rare sarcoma that has been shown to be highly effective to antiangiogenic agents and immune checkpoint inhibitors, but most reported studies about ASPS were concentrated on adult population. In this study, we aimed to describe the clinical features and therapeutic outcomes of ASPS in children. Methods: We retrospectively reviewed the records of patients with ASPS in our institution since Jan 2015. All patients included in this study were pathologically confirmed ASPS and aged under 12 years at the time of initial diagnosis. Demographic characteristics, tumor sizes, primary tumor sites, metastasis, treatments used, therapeutic responses and survivals were evaluated. Results: We identified a total of 56 patients to be initially diagnosed as ASPS since Jan 2015. A predisposition of high occurrence in head and neck (32.1%) was observed (versus 41.1% in limbs and 21.4% in trunk). 26 (46.4%) patients developed metastasis at the time of diagnosis or during follow-up. Tumors in tongue, pharynx and larynx had the least likelihood to metastasize (7.7%, P<0.05). Observation was recommended for 15 stage IV patients with only pulmonary metastasis. 7 (46.7%) patients remained stable until last follow up. The 1-year PFS rate was 83.3% and median progression-free survival time (PFS) was 29.4 months. 15 patients with progressive disease received mono or combined therapy. 11 patients received PD-1 monotherapy. 2 patients achieved partial response and 5 stable disease. The overall response rate was 18.2%. The median PFS of this group was 22.0 months, and the 1-year PFS rate was 70.0%. 4 patients received a combination therapy of PD-1 inhibitors plus tyrosine kinase inhibitors. All of them remained stable. No disease-related death occurred during follow-up. Conclusions: ASPS exhibits a higher occurrence in head and neck in children. ASPS originating from glossopharyngeal region tends to have a lower metastasis rate. ASPS displays a more indolent growth pattern in children, which makes observation a preferable choice for children with sole pulmonary metastasis. Pediatric ASPS appears to be less effective to targeted therapy and immunotherapy than adults. The treatment of progressive ASPS in children remains challenging. [ABSTRACT FROM AUTHOR]

Introduction: ASPS is a rare, soft tissue tumor which represents 0.2-1 % of soft tissue sarcomas. A characteristic nonreciprocal translocation is found in nearly all cases. The resulting ASPSCR1-TFE3 fusion gene is postulated to be involved in the pathogenesis of this tumor., Case Report: 29 years-old female presented with abdominal pain for few months. MRI and CT revealed a large necrotic abdominopelvic mass, which is extra-uterine, extra-ovarian, and peritoneal nodules. Exploratory laparotomy revealed a large mass arising from the distal part of the descending colon involving the mesentery and the surrounding peritoneum. She underwent left colectomy with primary anastomosis, and resection of the involved adjacent peritoneal and mesenteric surface nodules. Histopathology revealed ASPS involving the outer serosal layer of the large bowel wall negative margins. It also involved the resected mesenteric fat, greater omentum, and peritoneum. No further treatment was received as the patient traveled to home country., Discussion: The treatment of early-stage ASPS involves radical surgical excision of the primary tumor. Traditionally, patients with advanced ASPS have limited therapeutic options because of the resistance of the tumor to conventional cytotoxic chemotherapy, however, it is a targetable sarcoma. The response rate of metastatic ASPS to targeted therapy is clinically meaningful, and comparable to that of first-line chemotherapy. Most patients who received targeted therapy achieved disease control. Patients who had refractory or progressive disease to one targeted agent demonstrated a response to other agents. More randomized trials are warranted to expand treatment options and compare them to standard care regimens., Conclusion: In conclusion, while radical surgical excision remains crucial for early-stage ASPS, the landscape for advanced cases is evolving with targeted therapies showing promising results. However, further randomized trials are necessary to broaden the treatment options available and to evaluate these new therapies against existing standard care regimens. This ongoing research is vital to improving outcomes for patients with ASPS and tailoring more effective treatment strategies., Competing Interests: Conflict of interest statement I declare that this manuscript is original and has not been published before. It is not currently being considered for publication elsewhere. I have no conflicts of interest to disclose,, (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Soft tissue tumors of childhood are an extremely heterogeneous group of tumors that require precise diagnosis for therapy. In this article, selected tumors of uncertain origin that exhibit characteristic histological, immunophenotypical, and molecular features are addressed. Angiomatoid fibrous histiocytoma, alveolar soft part sarcoma, extrarenal rhabdoid tumor, synovial sarcoma, and desmoplastic small round cell tumor differ in their pathology, their clinical behavior, and prognosis., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Alveolar soft part sarcoma is a rare soft tissue neoplasm that accounts for approximately 1% of all sarcomas and is usually identified in the extremities in adults. The occurrence of alveolar soft part sarcoma in the orbit is extremely rare, estimated at approximately 5% – 15% among all cases of alveolar soft part sarcoma . Here, we present a case of 29-year-old woman with orbital alveolar soft part sarcoma. We describe the magnetic resonance and F-18 2-fluoro-2-deoxy-D-glucose-position emission tomography/computed tomography findings of this case. This young woman had a spindle-shaped mass. A higher signal compared to the extraocular muscle on T1-weighted images, numerous flow voids on T2-weighted images, and intense enhancement could be key findings of this disease.

BackgroundAlveolar soft part sarcoma (ASPS) is a rare sarcoma that has been shown to be highly effective to antiangiogenic agents and immune checkpoint inhibitors, but most reported studies about ASPS were concentrated on adult population. In this study, we aimed to describe the clinical features and therapeutic outcomes of ASPS in children.MethodsWe retrospectively reviewed the records of patients with ASPS in our institution since Jan 2015. All patients included in this study were pathologically confirmed ASPS and aged under 12 years at the time of initial diagnosis. Demographic characteristics, tumor sizes, primary tumor sites, metastasis, treatments used, therapeutic responses and survivals were evaluated.ResultsWe identified a total of 56 patients to be initially diagnosed as ASPS since Jan 2015. A predisposition of high occurrence in head and neck (32.1%) was observed (versus 41.1% in limbs and 21.4% in trunk). 26 (46.4%) patients developed metastasis at the time of diagnosis or during follow-up. Tumors in tongue, pharynx and larynx had the least likelihood to metastasize (7.7%, P

Alveolar soft part sarcoma (ASPS) is a rare soft tissue sarcoma with unique tumor characteristics, which is rare in children. Herein, we present the immunophenotype, treatment, and prognosis of three children with ASPS from The Second Xiangya Hospital of Central South University, and 51 children with ASPS have been reported in the previous literature, along with a focused review of the clinical features, pathological features, differential diagnosis, treatment, and prognosis of ASPS in pediatric patients.

Background: Atezolizumab has been studied in multiple indications for both pediatric and adult patient populations. Generally, clinical studies enrolling pediatric patients may not collect sufficient pharmacokinetic data to characterize the drug exposure and disposition because of operational, ethical, and logistical challenges including burden to children and blood sample volume limitations. Therefore, mechanistic modeling and simulation may serve as a tool to predict and understand the drug exposure in pediatric patients. Objective: To use mechanistic physiologically-based pharmacokinetic (PBPK) modeling to predict atezolizumab exposure at a dose of 15 mg/kg (max 1,200 mg) in pediatric patients to support dose rationalization and label recommendations. Methods: A minimal mechanistic PBPK model was used which incorporated age-dependent changes in physiology and biochemistry that are related to atezolizumab disposition such as endogenous IgG concentration and lymph flow. The PBPK model was developed using both in vitro data and clinically observed data in adults and was verified across dose levels obtained from a phase I and multiple phase III studies in both pediatric patients and adults. The verified model was then used to generate PK predictions for pediatric and adult subjects ranging from 2- to 29-year-old. Results: Individualized verification in children and in adults showed that the simulated concentrations of atezolizumab were comparable (76% within twofold and 90% within three-fold, respectively) to the observed data with no bias for either over- or under-prediction. Applying the verified model, the predicted exposure metrics including Cmin, Cmax, and AUCtau were consistent between pediatric and adult patients with a geometric mean of pediatric exposure metrics between 0.8- to 1.25-fold of the values in adults. Conclusion: The results show that a 15 mg/kg (max 1,200 mg) atezolizumab dose administered intravenously in pediatric patients provides comparable atezolizumab exposure to a dose of 1,200 mg in adults. This suggests that a dose of 15 mg/kg will provide adequate and effective atezolizumab exposure in pediatric patients from 2- to 18-year-old. [ABSTRACT FROM AUTHOR]

Background: Alveolar soft part sarcoma (ASPS) is a rare histological subtype of soft-tissue sarcoma, which remains refractory to conventional cytotoxic chemotherapy. We aimed to characterize ASPS and investigate whether the oncological outcome has improved over the past decade.Methods: One hundred and twenty patients with newly diagnosed ASPS from 2006 to 2017, identified from the Bone and Soft-Tissue Tumor Registry in Japan, were analyzed retrospectively.Results: The study cohort comprised 34 (28%) patients with localized ASPS and 86 (72%) with metastatic disease at presentation. The 5-year disease-specific survival (DSS) was 68% for all patients and 86% and 62% for localized and metastatic disease, respectively (p = 0.019). Metastasis at presentation was the only adverse prognostic factor for DSS (hazard ratio [HR]: 7.65; p = 0.048). Patients who were > 25 years (80%; p = 0.023), had deep-seated tumors (75%; p = 0.002), and tumors > 5 cm (5-10 cm, 81%; > 10 cm, 81%; p < 0.001) were more likely to have metastases at presentation. In patients with localized ASPS, adjuvant chemotherapy or radiotherapy did not affect survival, and 13 patients (45%) developed distant metastases in the lung (n = 12, 92%) and brain (n = 2, 15%). In patients with metastatic ASPS (lung, n = 85 [99%]; bone, n = 12 [14%]; and brain n = 9 [11%]), surgery for the primary or metastatic site did not affect survival. Prolonged survival was seen in patients who received pazopanib treatment (p = 0.045), but not in those who received doxorubicin-based cytotoxic chemotherapy. Overall, improved DSS for metastatic ASPS has been observed since 2012 (5-year DSS, from 58 to 65%) when pazopanib was approved for advanced diseases, although without a statistically significant difference (p = 0.117).Conclusion: The national study confirmed a unique feature of ASPS with frequent metastasis to the lung and brain but an indolent clinical course. An overall trend toward prolonged survival after the introduction of targeted therapy encourages continuous efforts to develop novel therapeutic options for this therapeutically resistant soft-tissue sarcoma. [ABSTRACT FROM AUTHOR]

Context Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor most commonly occurring in deep intramuscular plane of lower extremities of adolescents and young adults. It is a highly vascular, slow growing tumor with malignant potential having lung as the most common site of metastases at the time of presentation. Aims The aim is to review the imaging findings of ASPS and determine characteristic imaging features of this rare tumor. Materials and Methods Sixteen patients having histopathological diagnosis and preoperative imaging of ASPS attending the dedicated sarcoma clinic at our institute were included in the study. The demographic, clinical, and imaging data were retrieved from the case records and then evaluated for characteristic imaging features which may raise suspicion of ASPS. Results The patients ranged from 3 to 72 years of age and with a slight male preponderance. Of the eight CECTs evaluated, 62.5% tumors showed well-defined lobulated margins, 87.5% cases showed intense enhancement with presence of feeder vessels. On CEMRI of 10 patients, 70% had well circumscribed lobulated margins with intense enhancement and tortuous flow voids in most of them. All cases showed T2 hyperintense signal. Fourteen of 16 (87.5%) patients had metastatic disease with lung as the most common site (92.8%). Conclusion ASPS is a rare soft tissue sarcoma seen in children and young adults. Imaging may mimic a vascular malformation due to the presence of tortuous feeders. Misdiagnosis at an early stage may lead to later metastatic presentation of the disease, thus emphasizing the need to suspect it on imaging.

Purpose: Alveolar soft part sarcoma (ASPS) is a very rare type of soft tissue sarcomas which usually occurs in the limbs and trunk. Observations: A 25-year-old woman presented with proptosis and redness of the right eye for 8-month. She suffered from severe right upper lid edema, conjunctival chemosis, downward displacement of the globe, and proptosis. Radiological imaging was nonconclusive. Histopathological evaluations confirmed ASPS. The patient underwent exenteration as a lifesaving procedure. At 16-month follow-up, the patient is stable without any signs of recurrence or metastasis. Conclusions and importance: We report an extremely rare case of ASPS occurring in the superior rectus muscle. Few orbital ASPS cases have been reported in the literature. A literature review of orbital ASPS was done to shed lights on the diagnosis and management of this rare tumor.

Alveolar soft part sarcoma (ASPS) is a potentially lethal soft tissue tumor with a xropensity for distant metastasis. We report an exceedingly rare case of an ASPS arising from the pectoralis major in a young woman, with initial clinical findings mimicking a breast mass. We present the radiographic, immunohistochemical, and molecular workup leading to the correct diagnosis, with review of the differential diagnosis.

Alveolar soft part sarcoma (ASPS) is an ultra-rare chemo-resistant sarcoma in children, occurring preferentially in young adults. We aimed to describe and compare its clinical presentation and behaviour in children and young adults to determine whether the same therapeutic strategy should be addressed for both populations. National retrospective multicentre study of children (0–18 years) vs. young adults (19–30 years) included in the "ConticaBase" sarcoma database, treated for ASPS between 2010 and 2019 with pathology reviewed via the NETSARC + network. Overall, 45 patients were identified, 19 children (42%) and 26 young adults (58%). All ASPS diagnoses were confirmed with TFE3 rearrangement by immunohistochemistry or FISH. All clinical characteristics were balanced between both populations with frequent metastases at diagnosis (8/19 vs. 10/26). The therapeutic strategy was based on surgery (17/19 vs. 21/26), radiotherapy (8/19 vs. 12/26) ± systemic treatment (8/19 vs. 9/26). In patients with initially localized disease, metastatic relapse occurred only in adults (8/16), whereas metastatic progression was present in both metastatic groups (5/8 vs. 8/10). After a median follow-up of 5.2 years (range, 0.2–12.2), 5-year EFS was 74% [95%CI, 56–96] vs. 47% [30–74] (p = 0.071) respectively, and 5-year OS was 95% [85−100] vs. 85% [70−100] (p = 0.84). For localized tumours, 5-year MFS was 100% [100−100] vs. 60% [39–91] (p = 0.005). The 5-year OS of all patients with metastasis at diagnosis was 80.2% (62.2%–100%). ASPS appears to have the overall same clinical characteristics, but a more aggressive behaviour in young adults than in children. However, despite frequent metastases at diagnosis, long-term survival is high in both groups. Overall, the same therapeutic strategies may be considered for both populations. • Alveolar Soft Part Sarcoma is an ultra-rare sarcoma in children and young adults. • Clinical presentation and behaviour are similar in children and young adults. • Alveolar Soft Part Sarcoma has a more aggressive behaviour in young adults than in children • Despite frequent metastases at diagnosis, long-term survival is high in young patients. • The same therapeutic strategies should be considered for both populations. [ABSTRACT FROM AUTHOR]