Primary Epithelioid Sarcoma of the Conchal Bowl in a 64-Year-Old Male: A Case Report and Review of the Literature.

ABSTRACT: Epithelioid sarcoma (ES) is a distinctive malignant mesenchymal neoplasm with atypical epithelioid cells palisading around a central zone of necrosis. ES is a rare entity even in soft tissue pathology. Immunohistochemically, tumors usually show diffuse epithelial membrane antigen and cytokeratin expression and loss of nuclear INI1 (SMARCB1) expression. Here, we report a case of a 64-year-old man with ES arising in the left conchal bowl. Given the clinical presentation including patient's age, sun-exposed area of skin, and slow-growing, asymptomatic, small pink pearly papule, this patient was initially misdiagnosed with basal cell carcinoma clinically and treated with topical imiquimod at an outside facility. The lesion continued to grow and eventually became symptomatic despite the treatment after which biopsy was obtained. Despite the unusual anatomic site and the patient's age, the microscopic and immunohistochemical findings were characteristic of conventional-type ES. Our case shows that ES can arise in rare locations and in older adults where it may be more easily misdiagnosed clinically and pathologically as a nonmelanoma skin cancer.

Diffuse spinal cord metastasis after resection of SMARCB1 sinonasal carcinoma manifesting with a right foot drop-a case report.

INTRODUCTION: The sinonasal carcinoma are rare tumors of the head and neck. The undifferentiated sinonasal carcinoma subtypes are constantly being explored and new mutations, with different prognosis markers and biological behaviors are being described. The SMARCB1 negative sinonasal carcinoma subtypes have been recently described with few reports of leptomeningeal and spinal cord invasion. CASE PRESENTATION: This study presents the case of a 59-year-old woman, with no previous disease, presenting initially with epistaxis that evolved to cranial nerve deficits and a left eye complete oftalmoplegia. After diagnostic investigation, she had a diagnosis of a left ethmoid sinus sinonasal carcinoma. Following resection of the tumor, she evolved with a right foot drop that eventually has been linked to diffuse spinal cord impairment. The histopathological diagnosis confirmed a SMARCB1 negative sinonasal carcinoma. Due to the diffuse metastasis, she underwent palliative care and died eight months after the surgery. DISCUSSION: Spinal cord metastasis may manifest with different clinical signs. Our case shows a rare manifestation of SMARCB1-deficient sinonasal carcinoma, a new subtype of sinonasal carcinoma, summarizing the importance of a high grade of suspicion of spinal cord invasion on these patients. SMARCB1 sinonasal carcinomas are rare new tumors of the head and neck, whose biological behaviors are yet to be explored. To the best of our knowledge, this is one of the few case reports describing simultaneous spread of this tumor to the central nervous system and spinal cord.

Case Report of Small Cell Carcinoma of the Ovary, Hypercalcemic Type (Ovarian Rhabdoid Tumor) with SMARCB1 Mutation: A Literature Review of a Rare and Aggressive Condition.

Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a rare and aggressive condition that is associated with the SMARCA4 mutation and has a dismal prognosis. It is generally diagnosed in young women. Here, we report a case of a young woman with SCCOHT harboring a rare molecular finding with a highly aggressive biological behavior. The patient had a somatic SMARCB1 mutation instead of an expected SMARCA4 alteration. Even though the patient was treated with high-dose chemotherapy followed by stem cell transplantation, she evolved with disease progression and died 11 months after her first symptoms appeared. We present a literature review of this rare disease and discuss the findings in the present patient in comparison to expected molecular alterations and options for SCCOHT treatment.

SMARCB1 (Integrase Interactor 1)-Deficient Sinonasal Carcinoma of the Maxillary Sinus: A Newly Described Sinonasal Neoplasm.

SMARCB1 (integrase interactor 1) is a tumor suppressor gene encoded on chromosome 22q11.2 that encodes a core subunit of SWI/SNF chromatin remodeling complexes and plays a critical role in regulating gene expression and chromatin structure. We describe a case of SMARCB1 (integrase interactor 1)-deficient sinonasal carcinoma of the left maxillary sinus in a 63-year-old woman with an initial presentation of numbness of the maxillary teeth and facial swelling.

SMARCB1 (INI-1) and NUT immunoexpression in a large series of head and neck carcinomas in a Brazilian reference center.

BACKGROUND: SMARCB1 (INI-1)-deficient carcinomas and NUT carcinomas are aggressive neoplasms, often affecting the sinonasal region. Not uncommonly, their diagnoses are made retrospectively. METHODS: Through SMARCB1 (INI-1) and NUT immunomarkers, 643 head and neck carcinomas were assessed retrospectively. Moreover, SMARCB1 (INI-1)-deficient and NUT carcinomas were additionally evaluated by immunohistochemistry, as well as in situ hybridization analysis for HPV and EBV. RESULTS: Four SMARCB1 (INI-1)-deficient carcinomas (located in lower lip, soft palate, hypopharynx and vocal cord, this latter high-risk HPV positive) and three NUT carcinomas (all located in oropharynx) were detected, previously diagnosed as nonkeratinizing or moderately differentiated squamous cell carcinoma. All cases showed squamous differentiation. NUT carcinomas than SMARCB1 (INI-1)-deficient carcinomas showed low overall survival rate. CONCLUSION: The current cases expand the clinicopathological spectrum of SMARCB1 (INI-1)-deficient carcinomas and NUT carcinomas. Notably, the diagnosis of these cases is easily reached through immunohistochemistry, with impact on their accurate classification, treatment, and prognosis.

Metastatic poorly differentiated chordoma: the eyes do not see what the mind does not know

Chordoma is a rare tumor. It has unique clinical, pathological and immunohistochemical characteristics. Accurate diagnosis is essential as the tumor shows an aggressive clinical course and requires a multimodal therapeutic approach. A case with wide spread distant metastatic disease that was initially thought to represent metastatic thyroid carcinoma is presented. Appropriate clincopathologic correlation and the histologic findings raised the possibility of poorly differentiated chordoma. The diagnosis was confirmed by immunohistochemistry for INI-1 and Brachyury. The approach to the diagnosis emphasizing the clinical and pathologic findings of this case is discussed and reviewed in the context of the published literature.

Epithelial-Myoepithelial Carcinoma: Frequent Morphologic and Molecular Evidence of Preexisting Pleomorphic Adenoma, Common HRAS Mutations in PLAG1-intact and HMGA2-intact Cases, and Occasional TP53, FBXW7, and SMARCB1 Alterations in High-grade Cases.

We hypothesized that there is a relationship between the preexisting pleomorphic adenoma [PA]), histologic grade of epithelial-myoepithelial carcinomas (EMCAs), and genetic alterations. EMCAs (n=39) were analyzed for morphologic and molecular evidence of preexisting PA (PLAG1, HMGA2 status by fluorescence in situ hybridization, FISH, and FGFR1-PLAG1 fusion by next-generation sequencing, NGS). Twenty-three EMCAs were further analyzed by NGS for mutations and copy number variation in 50 cancer-related genes. On the basis of combined morphologic and molecular evidence of PA, the following subsets of EMCA emerged: (a) EMCAs with morphologic evidence of preexisting PA, but intact PLAG1 and HMGA2 (12/39, 31%), (b) Carcinomas with PLAG1 alterations (9/39, 23%), or (c) HMGA2 alterations (10/39, 26%), and (d) de novo carcinomas, without morphologic or molecular evidence of PA (8/39, 21%). Twelve high-grade EMCAs (12/39, 31%) occurred across all subsets. The median disease-free survival was 80 months (95% confidence interval, 77-84 mo). Disease-free survival and other clinicopathologic parameters did not differ by the above defined subsets. HRAS mutations were more common in EMCAs with intact PLAG1 and HMGA2 (7/9 vs. 1/14, P<0.001). Other genetic abnormalities (TP53 [n=2], FBXW7 [n=1], SMARCB1 deletion [n=1]) were seen only in high-grade EMCAs with intact PLAG1 and HMGA2. We conclude that most EMCAs arose ex PA (31/39, 80%) and the genetic profile of EMCA varies with the absence or presence of preexisting PA and its cytogenetic signature. Progression to higher grade EMCA with intact PLAG1 and HMGA2 correlates with the presence of TP53, FBXW7 mutations, or SMARCB1 deletion.

Epigenetic Alterations in Bone and Soft Tissue Tumors.

Human malignancies are driven by heritable alterations that lead to unchecked cellular proliferation, invasive growth and distant spread. Heritable changes can arise from changes in DNA sequence, or, alternatively, through altered gene expression rooted in epigenetic mechanisms. In recent years, high-throughput sequencing of tumor genomes has revealed a central role for mutations in epigenetic regulatory complexes in oncogenic processes. Through interactions with or direct modifications of chromatin, these proteins help control the accessibility of genes, and thus the transcriptional profile of a cell. Dysfunction in these proteins can lead to activation of oncogenic pathways or silencing of tumor suppressors. Although epigenetic regulators are altered across a broad spectrum of human malignancies, they play a particularly central role in tumors of mesenchymal and neuroectodermal origin. This review will focus on recent advances in the understanding of the molecular pathogenesis of a subset of tumors in which alterations in the polycomb family of chromatin modifying complexes, the SWI/SNF family of nucleosome remodelers, and histones play a central role in disease pathogenesis. Although this review will focus predominantly on the molecular mechanisms underlying these tumors, each section will also highlight areas in which an understanding of the molecular pathogenesis of these diseases has led to the adoption of novel immunohistochemical and molecular markers.

A complex karyotype in an atypical teratoid/rhabdoid tumor: case report and review of the literature.

Atypical teratoid/rhabdoid tumor (AT/RT) is a highly aggressive and uncommon neoplasm of the central nervous system that usually occurs in children less than 2 years of age. It is characterized by deletions and/or mutations of the INI1 tumor suppressor gene located in chromosome band 22q11.2. We performed cytogenetic and molecular studies of an AT/RT on a 15-month-old boy. The tumor showed a complex karyotype with one cell line showing monosomy 22 and another near-tetraploid one with additional chromosomal abnormalities, involving chromosomes 2, 3, 5, 6, and Y, which had not been previously described. Sequence analysis of the tumor did not identify mutations of the INI1 gene. The karyotypic evolution observed in this tumor suggests that INI1 has an epigenetic role in the maintenance of genome integrity by affecting genes, which produces mitotic defects and polyploidy. Finally, this case is the first to support the theory that loss of INI1 could induce the chromosomal instability that might be responsible for the genesis of this tumor.