Proximal-Type Epithelioid Sarcoma in Skull Base: a Pathological Diagnosis Challenge with Other Intracranial Tumors

Clinicopathological Characteristics, Treatment, and Survival in Patients Diagnosed With Proximal-Type Epithelioid Sarcoma: A Case Report and Systematic Review

Epithelioid sarcoma is a rare entity that shows a predilection for the young and middle-aged population. There are two subtypes, i.e., the distal or conventional type, which is located in distal extremities, and the proximal type, located in proximal areas of the extremities, pelvis, perineal, and genital region. The latter is characterized by more aggressive behavior, a higher recurrence rate, and poor prognosis. Histopathological and immunohistochemical diagnoses are key to correct and timely treatment and a higher survival rate. We report a case of a 41-year-old man who presented a palpable progressive growth mass in the hypogastrium. The disease time was of nine months, and the tumor was resected, but it recurred a few months later in the same location. Computed tomography (CT) scans showed images suggestive of lung metastasis and the patient had to undergo a second surgery. He received eight cycles of chemotherapy and a subsequent CT scan control showed the progression of the disease, so a new chemotherapy regimen was established. The patient received three cycles of chemotherapy without improvement, so he decided to discontinue treatment. His last outpatient medical consultation was in January 2022. A systematic review of the studies published in PubMed and Google Scholar was performed. We identified 291 articles, but only 41 reports and case series were included, with a total of 55 patients. It is important to include this type of tumor in the differential diagnosis of epithelial tumors due to its aggressive behavior. Correct and timely diagnosis is crucial to obtain lower recurrence rates, lower mortality, and higher survival rates in these patients.

Clinical characteristics and survival analysis of patients with limb epithelioid sarcoma

Limb epithelioid sarcoma (LES) is a rare and aggressive soft tissue sarcoma, which is scarcely reported. Therefore, the current study was performed to analyze the clinicopathologic features and risk factors of survival among patients with LES. By using the Surveillance, Epidemiology, and End Results database, data were obtained regarding patients who were diagnosed with LES for the period between 2010 and 2016. We first analyzed overall survival (OS) and cancer-specific survival (CSS) by applying univariate Cox regression analysis. Then we performed multivariate analysis to confirm independent predictors of survival. In total, we identified 475 patients with LES for survival analysis, of which 291 were males (61.3%) and 184 females (38.7%). The mean and median age at diagnosis were 38 and 36 years, respectively. The 5-year OS and CSS rates among Patients with LES were 65.4% and 69.5%, respectively. Gender, age, tumor stage, tumor size, and treatment type were significant predictors of OS on both univariate and multivariate analyses (P < .05). As for CSS, multivariable analysis revealed that age <60 years, localized stage, and tumor size <5 cm were significantly associated with increased survival (P < .05). Predictors of improved survival for LES patients include gender, age, tumor stage, tumor size, and treatment type. Surgery only was recommended for treating LES patients. Future studies are warranted to determine effective treatment types for LES patients.

Primary adult sellar SMARCB1/INI1-deficient tumor represents a subtype of atypical teratoid/rhabdoid tumor

Loss of function in SMARCB1/INI1 has been observed in a group of malignancies collectively defined as SMARCB1/INI1-deficient neoplasms. Primary intracranial SMARCB1/INI1-deficient tumors in adults are extremely rare. We collected eight primary adult sellar SMARCB1/INI1-deficient tumors to study their clinicopathological and (epi)genetic characteristics. We performed a comprehensive assessment of the clinical, radiological, morphological and immunohistochemical features. FISH analysis for the SMARCB1 locus and target exome sequencing for 425 cancer relevant genes were performed. Furthermore, six bona fide proximal epithelioid sarcoma (PES), fourteen atypical teratoid/rhabdoid tumors (ATRT) in brain and five pediatric poorly differentiated chordomas (PDC) in the clivus were collected for comparative analysis of differential diagnostic maker expression and DNA methylation profile. The median age was 47.1 years, ranging from 26 to 73 years. On morphology, tumors were characterized by sheets of monomorphic larger epithelioid-like cells, in two cases with rhabdoid cells. "Stag-horn" vasculatures were observed in five cases. The loss of INI1 protein expression, co-expression of epithelial makers and mesenchymal markers were observed in all cases. CD34 expression was observed in six cases. Heterozygous deletion of SMARCB1/INI1 was confirmed using FISH in six cases. The results of target exome sequencing showed three patients harbored heterozygous point mutations in SMARCB1. The epigenetic features of the primary adult sellar SMARCB1/INI1-deficient tumors resembled the ATRT-MYC subgroup, but clustered apart from PES and PDC. Based on epigenetic characteristics, primary adult sellar SMARCB1/INI1-deficient tumors represent a subtype of ATRT with similar epigenetic characteristics of ATRT-MYC subgroup. Our findings suggest that DNA methylation profiling should be utilized for differential diagnosis for the majority of epithelioid sarcoma and (sellar) rhabdoid tumor.

Epithelioid Sarcoma Arising in a Long-Term Survivor of an Atypical Teratoid/Rhabdoid Tumor in a Patient With Rhabdoid Tumor Predisposition Syndrome

Rhabdoid tumor predisposition syndrome (RTPS) is defined as the presence of a SMARCB1 or SMARCA4 genetic aberration in a patient with malignant rhabdoid tumor. Patients with RTPS are more likely to present with synchronous or metachronous rhabdoid tumors. Based on the current state of rhabdoid tumor taxonomy, these diagnoses are based largely on patient demographics, anatomic location of disease, and immunohistochemistry, despite their nearly identical histologic and immunohistochemical profiles. Thus, the true distinction between such tumors remains a diagnostic challenge. Central nervous system atypical teratoid/rhabdoid tumor (AT/RT) is a rare, aggressive, primarily pediatric malignancy with variable histologic features and a well documented association with loss of SMARCB1 expression. Epithelioid sarcoma (ES) is a rare soft tissue tumor arising in patients of all ages and characteristically staining for both mesenchymal and epithelial immunohistochemical markers while usually demonstrating loss of SMARCB1 expression. To our knowledge we herein present the first documented case of a patient with RTPS who presented with metachronous AT/RT and ES.

Proximal-type epithelioid sarcoma of the oral cavity: a case report and literature review

Proximal-type epithelioid sarcoma (PES) is an exceedingly rare malignant tumor of soft tissue; PES within the oral cavity is even rarer. Pathologic examination is the primary diagnostic modality, and surgical treatment is recommended as the preferred method for the treatment of PES. Currently, there is a paucity of literature that systematically reports on PES in the oral cavity. Here, we describe a 42-year-old man with PES in the oral cavity, which showed positivity for vimentin, cytokeratin, CD31, S-100 but did not express BCL-2, HMB-45, or desmin. We performed a wide excision and neck dissection, and then used the free anterolateral thigh flap to reconstruct the defect in the soft tissue. Furthermore, we review the current literature with regard to diagnosis and treatment of PES.