Targeting stroma and tumor, silencing galectin 1 treats orthotopic mouse hepatocellular carcinoma.

This study examines inhibiting galectin 1 (Gal1) as a treatment option for hepatocellular carcinoma (HCC). Gal1 has immunosuppressive and cancer-promoting roles. Our data showed that Gal1 was highly expressed in human and mouse HCC. The levels of Gal1 positively correlated with the stages of human HCC and negatively with survival. The roles of Gal1 in HCC were studied using overexpression (OE) or silencing using Igals1 siRNA delivered by AAV9. Prior to HCC initiation induced by RAS and AKT mutations, lgals1-OE and silencing had opposite impacts on tumor load. The treatment effect of lgals1 siRNA was further demonstrated by intersecting HCC at different time points when the tumor load had already reached 9% or even 42% of the body weight. Comparing spatial transcriptomic profiles of Gal1 silenced and OE HCC, inhibiting matrix formation and recognition of foreign antigen in CD45+ cell-enriched areas located at tumor-margin likely contributed to the anti-HCC effects of Gal1 silencing. Within the tumors, silencing Gal1 inhibited translational initiation, elongation, and termination. Furthermore, Gal1 silencing increased immune cells as well as expanded cytotoxic T cells within the tumor, and the anti-HCC effect of lgals1 siRNA was CD8-dependent. Overall, Gal1 silencing has a promising potential for HCC treatment.

Primary and secondary angiosarcomas of the liver: a multi-institutional study of 32 cases.

Angiosarcomas involving the liver can be hepatic primary or metastasis from another anatomic site, which have not been systematically compared. We analyzed a series of liver biopsy or resection specimens carrying a diagnosis of angiosarcoma collected between 2005 and 2022 at 3 tertiary medical centers. The cohort included 32 patients (20 M and 12 F) with a median age of 64 years. Nineteen were primary hepatic angiosarcoma (PHA) and 13 metastatic angiosarcoma to liver (MA). Males were predominant in PHA (15/19, 78%) compared to MA (5/13, 38%, P = .025). There was no age difference between the 2 groups. Five cases had background hepatic cirrhosis, which more likely harbored PHA (4/5, 80%). Multifocality and multiorgan involvement were common in both groups. Tumor size was significantly larger in PHA than in MA (10.4 versus 4.7 cm, P < .01). Histologically, there were no differences in terms of tumor morphology (spindled versus epithelioid) and growth patterns (vasoformative versus solid) between the 2 groups. Immunohistochemically, all tumor cells were positive for CD31 (28/28, 100%) and ERG (18/18, 100%). Molecular analysis in 5 cases demonstrated different mutation profiles involving different genes, including MTOR, PIK3CA, ARID1A, CDKN2A, PTEN, TP53, ATRX, KDR/VEGFR2, and so forth. On follow-up, 30 patients (93%) died of disease, with a median survival of 114 days. Univariate and multivariate analyses revealed PHA and epithelioid morphology to be associated with worse survival (P < .05), while treatment was associated with better survival (P < .001). Our results confirmed that angiosarcoma, particularly PHA, is extremely aggressive. Epithelioid morphology is an adverse prognosticator and may be used for tumor subclassification.

Ovarian Granulosa Cell Tumor Initially Presenting as a Giant Liver Mass Radiologically Mimicking Primary Cystic Cholangiocarcinoma.

BACKGROUND: Ovarian granulosa cell tumor (GCT) is a rare type of malignant sex-cord stromal tumor, with adult and juvenile types. The ovarian GCT initially presented as a giant liver mass clinically mimicking primary cholangiocarcinoma is exceedingly rare. CASE REPORT: We report such a case of a 66-year-old woman who presented with right upper quadrant pain. Abdominal magnetic resonance imaging (MRI) and a subsequently fused positron emission tomography/computed tomography (PET/CT) showed a solid and cystic mass with hypermetabolic activity concerning intrahepatic primary cystic cholangiocarcinoma. A fine-needle core biopsy of the liver mass showed coffee-bean-shaped tumor cells. The tumor cells were positive for Forkhead Box L2 (FOXL2), inhibin, Wilms tumor protein 1 (WT-1), steroidogenic factor 1 (SF1), vimentin, estrogen receptor (ER), and smooth muscle actin (SMA). The histologic features and immunoprofile supported a metastatic sex-cord stromal tumor favoring granulosa cell tumor, adult type. Strata next-generation sequencing test was performed on the liver biopsy and FOXL2 c.402C>G (p.C134W) mutation was present, consistent with granulosa cell tumor. CONCLUSION: To the best of our knowledge, this is the first documented case of ovarian granulosa cell tumor with FOXL2 mutation initially presenting as a giant liver mass clinically mimicking primary cystic cholangiocarcinoma.

Metabolic reprogramming and its clinical implication for liver cancer.

Cancer cells often encounter hypoxic and hypo-nutrient conditions, which force them to make adaptive changes to meet their high demands for energy and various biomaterials for biomass synthesis. As a result, enhanced catabolism (breakdown of macromolecules for energy production) and anabolism (macromolecule synthesis from bio-precursors) are induced in cancer. This phenomenon is called "metabolic reprogramming," a cancer hallmark contributing to cancer development, metastasis, and drug resistance. HCC and cholangiocarcinoma (CCA) are 2 different liver cancers with high intertumoral heterogeneity in terms of etiologies, mutational landscapes, transcriptomes, and histological representations. In agreement, metabolism in HCC or CCA is remarkably heterogeneous, although changes in the glycolytic pathways and an increase in the generation of lactate (the Warburg effect) have been frequently detected in those tumors. For example, HCC tumors with activated ß-catenin are addicted to fatty acid catabolism, whereas HCC tumors derived from fatty liver avoid using fatty acids. In this review, we describe common metabolic alterations in HCC and CCA as well as metabolic features unique for their subsets. We discuss metabolism of NAFLD as well, because NAFLD will likely become a leading etiology of liver cancer in the coming years due to the obesity epidemic in the Western world. Furthermore, we outline the clinical implication of liver cancer metabolism and highlight the computation and systems biology approaches, such as genome-wide metabolic models, as a valuable tool allowing us to identify therapeutic targets and develop personalized treatments for liver cancer patients.

Clear-cell Variant of Mucoepidermoid Carcinoma Presenting as a Palatal Mass in a 10-Year-old Boy.

BACKGROUND: The clear-cell variant of mucoepidermoid carcinoma (MEC) involving minor salivary glands is extremely rare in children. CASE REPORT: We report a case of clear-cell variant MEC in the minor salivary gland in a 10-year-old boy who presented with a mass of the right hard palate. Fine-needle aspiration showed features suggestive of clear-cell variant of MEC. Microscopically, the tumor cells showed predominant clear cells and scattered mucous cells. There was increased mitotic activity (6/mm2). No tumor necrosis or nuclear pleomorphism was identified. The tumor cells were positive for cytokeratin 7 (CK7), tumor protein p63, P40 (ΔNp63), CK5/6 and mucicarmine. Rearrangement of mastermind-like transcriptional coactivator 2 (MAML2) (11q21) gene was present in the tumor cells by fluorescence in situ hybridization, supporting the diagnosis of an intermediate-grade clear-cell variant of MEC. A right infrastructure maxillectomy for palate carcinoma with negative margins was performed. Grossly, the tumor was a 2.1 cm well-circumscribed, friable, pale tan mass with focal areas of cystic change. The final pathological diagnosis was clear-cell variant of MEC, intermediate grade, pT2. Post surgery, the patient recovered and was doing well, with no tumor recurrence or metastasis at the 6-month follow-up. CONCLUSION: To the best of our knowledge, this is the first documented case of clear-cell variant MEC in a child. Due to low to intermediate tumor grade, an overtly aggressive treatment should be avoided in a child.

Exosomal microRNAs and Progression of Nonalcoholic Steatohepatitis (NASH).

Nonalcoholic fatty liver disease (NAFLD)/metabolic associated fatty liver disease (MAFLD) is becoming a public health problem worldwide. Steatosis as the simple form and nonalcoholic steatohepatitis (NASH) as its progression form are commonly seen in liver biopsy specimens from patients with obesity, diabetes, hyperlipidemia, hypertension, and the use of certain drugs. Patients with NASH and advanced fibrosis were associated with increased risks of liver-related complications, including hepatocellular carcinoma (HCC). However, the mechanisms regarding the progression from simple steatosis to NASH fibrosis remain incompletely understood. Because NASH-caused liver injury is a complex process and multiple cell types are involved, intercellular communication is likely mediated by extracellular vesicles. Exosomes are a type of small extracellular vesicles and contain various cellular molecules, including proteins, messenger RNAs (mRNAs), and microRNAs (miRNAs). MiRNAs are short, non-coding RNA species that are important post-transcriptional regulators of gene expression and may play an important role in the pathogenesis of NALFD/NASH. In this article, we review the articles about NASH and exosomal miRNAs published in the most recent English literature through PubMed search and discuss the most recent criteria for histological diagnosis, pathogenesis from steatosis to NASH, roles of exosomal miRNAs in NASH pathogenesis and progression, as well as their potential in future clinical diagnosis and treatment for patients with NASH.

Molecular Characteristics and Immunogenomic Profiling of Cholangioblastic Variant of Intrahepatic Cholangiocarcinoma in a 68-year-old Patient.

BACKGROUND/AIM: Cholangioblastic variant of intrahepatic cholangiocarcinoma (CVICC) is an exceedingly rare primary biliary tract tumor and typically occurs in young patients with a median age of 24.5-year-old. It can mimic metastatic well-differentiated neuroendocrine tumors in the liver with its similar histologic and immunophenotypic features. CASE REPORT: We hereby report a CVICC in a 68-year-old female patient with distinctive biphasic cytologic features. The patient was diagnosed and treated as a metastatic well differentiated neuroendocrine tumor. The recurrent liver tumor was resected and the tumor cells were strongly positive for Inhibin A and cytokeratin 19 (CK19), focally and weakly positive for synaptophysin and chromogranin, and negative for Insulinoma associated protein 1 (INSM1). Ribonucleic acid (RNA) sequencing showed that the tumor bared a characteristic Nipped-B-like protein (NIPBL)-Nucleus accumbens-associated protein 1 (NACC1) gene fusion. CONCLUSION: To the best of our knowledge, this is the first documented case in an elder patient of this entity with NIPPL-NACC1 gene fusion. Acknowledgment of the biphasic cytology, screening with Inhibin A in suspicious cases, and coupled with a molecular study may facilitate accurate classification of this aggressive tumor and lead to proper clinical management.

Emerging Trends in the Pathological Research of Human Papillomavirus-positive Oropharyngeal Squamous Cell Carcinoma.

Oropharyngeal squamous cell carcinomas (OPSCCs) have shown an alarming rate of increase in incidence over the past several decades, markedly in men. In the United States, transcriptionally-active human papillomavirus (HPV), particularly HPV 16, has become the highest contributive agent of OPSCCs, affecting approximately 16,000 people a year. Compared to patients with HPV-negative OPSCCs, patients with HPV-positive OPSCCs exhibit better health responses to chemoradiotherapy and an overall increase in long-term survival. Despite promising treatment options, many OPSCCs are discovered at an advanced stage, and ~20% of cases will recur after definitive treatment. Therefore, extensive research is ongoing to identify new targets for precision treatment and to stratify tumor prognosis. The aim of this review is to capture the most updated research on HPV-positive OPSCCs, emphasizing their relevance as potential new targets for precision medicine and survival prognosis.

Tumor microenvironment in pancreatic ductal adenocarcinoma: Implications in immunotherapy.

Pancreatic ductal adenocarcinoma is one of the most aggressive and lethal cancers. Surgical resection is the only curable treatment option, but it is available for only a small fraction of patients at the time of diagnosis. With current therapeutic regimens, the average 5-year survival rate is less than 10% in pancreatic cancer patients. Immunotherapy has emerged as one of the most promising treatment options for multiple solid tumors of advanced stage. However, its clinical efficacy is suboptimal in most clinical trials on pancreatic cancer. Current studies have suggested that the tumor microenvironment is likely the underlying barrier affecting immunotherapy drug efficacy in pancreatic cancer. In this review, we discuss the role of the tumor microenvironment in pancreatic cancer and the latest advances in immunotherapy on pancreatic cancer.

Synchronous Penile Squamous Cell Carcinoma, Bladder Urothelial Carcinoma and Prostate Adenocarcinoma Diagnosed in One Procedure.

BACKGROUND: The synchronous diagnoses of three primary malignancies in a patient is rare and represents a difficult treatment challenge. We report a rare case of an 81-year-old male with synchronous triple urogenital cancers including penile squamous cell carcinoma, bladder papillary urothelial carcinoma, and prostate adenocarcinoma. CASE REPORT: The patients presented with a penile lesion with blood draining through the foreskin. Further examination with cystoscopy during the biopsy procedure revealed a 1.5-cm tumor along the left lateral bladder wall and a firm prostate in bilateral lobes. Diagnosis of penile squamous cell carcinoma was confirmed by biopsies of the penile lesions and glans as confirmed by cystoscopy and histological evaluation of the tissue obtained by transurethral resection of the bladder. Biopsies of the prostatic urethra confirmed a diagnosis of prostate adenocarcinoma. All biopsies were performed in a single procedure. Pathology findings revealed moderately differentiated squamous cell carcinoma (p16+) invading the lamina propria of the glans penis, noninvasive low-grade papillary urothelial carcinoma of the bladder, and high-grade prostatic adenocarcinoma (Gleason score 5+5=10) within the prostatic stroma. CONCLUSION: Review of the English literature through PubMed search suggests that this specific combination of synchronous triple urogenital cancer is the first documented case of its kind. Incidence, diagnosis, and treatment for the combination of these cancer types are discussed with consideration for concurrent management of three primary cancers.

Metastatic SMARCB1 Deficient Skin Carcinoma With Neuroendocrine Differentiation in the Parotid Glands Clinically Mimicking Primary Salivary Gland Malignancy: Unusual Case With Diagnostic Pitfalls.

BACKGROUND/AIM: SMARCB1(INI1)-deficient cutaneous carcinomas are an emerging subset of rare tumors, with only a few cases reported, making its diagnosis challenging. CASE REPORT: A 84-year-old male with a history of prostate adenocarcinoma and skin squamous cell cancer presented with a rapidly growing upper neck mass. Computed tomography (CT) and positron emission tomography (PET)/CT scans were suspicious of a salivary gland neoplasm of the parotid glands. Needle core biopsy of the right parotid gland mass showed poorly differentiated carcinoma. The patient underwent bilateral superficial parotidectomies and neck lymph nodes dissection. Histologically, the tumor showed rhabdoid and plasmacytoid morphology with diffuse loss of SMARCB1, positive deltaNp63 (p40), focally positive synaptophysin, and 80% of Ki67 index. Retrospectively, SMARCB1 deficiency carcinoma with squamous and neuroendocrine differentiation was confirmed in the prior skin lesion of the right frontal scalp. The patient had a poor prognosis even though post-surgical radiation therapy was given. CONCLUSION: We present a unique case of metastatic SMARCB1-deficient cutaneous carcinoma in the parotid glands with both squamous and neuroendocrine differentiation. This entity should be considered in any difficult-to-classify skin carcinoma, as timely definitive diagnosis will be mandatory for optimizing therapy.

New insights in diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms.

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are rare epithelial neoplasms derived from pluripotent endocrine cells along the gastrointestinal tract and pancreas. GEP-NENs are classified into well-differentiated neuroendocrine tumors and poorly differentiated neuroendocrine carcinomas. Despite overlapping morphological features, GEP-NENs vary in molecular biology, epigenetic, clinical behavior, treatment response, and prognosis features and remain an unmet clinical challenge. In this review, we introduce recent updates on the histopathologic classification, including the tumor grading and staging system, molecular genetics, and systemic evaluation of the diagnosis and treatment of GEP-NENs at different anatomic sites, together with some insights into the diagnosis of challenging and unusual cases. We also discuss the application of novel therapeutic approaches for GEP-NENs, including peptide receptor radionuclide therapy, targeted therapy, and immunotherapy with immune checkpoint inhibitors. These findings will help improve patient care with precise diagnosis and individualized treatment of patients with GEP-NENs.

Non-invasive detection and complementary diagnosis of liver metastases via chemokine receptor 4 imaging.

Noninvasive detection of early-stage liver metastases from different primary cancers is a pressing unmet medical need. The lack of both molecular biomarkers and the sensitive imaging methodology makes the detection challenging. In this study, we observed the elevated expression of chemokine receptor 4 (CXCR4) in uveal melanoma (UM) patient liver tissues, and high CXCR4 expression in liver metastases of UM murine models, regardless of the expression levels in the primary tumors. Based on these findings, we identified CXCR4 as an imaging biomarker and exploited a CXCR4-targeted MRI contrast agent ProCA32.CXCR4 for molecular MRI imaging. ProCA32.CXCR4 has strong CXCR4 binding affinity, high metal selectivity, and r1 and r2 relaxivities, which enables the sensitive detection of liver micrometastases. The MRI imaging capacity for detecting liver metastases was demonstrated in three UM models and one ovarian cancer model. The imaging results were validated by histological and immunohistochemical analysis. ProCA32.CXCR4 has strong potential clinical application for non-invasive diagnosis of liver metastases.

Thyroid Follicular Cell-derived Carcinomas in a Background of Multiple Adenomatous Nodules Leading to a Diagnosis of PTEN Hamartoma Tumor Syndrome in an Adult Patient With a Novel RECQL4 Mutation.

BACKGROUND: Phosphatase and tensin homolog (PTEN) hamartoma tumor syndrome (PHTS) is a complex disorder. Carriers develop hamartomatous tumors, with an increased risk for developing malignant tumors in multiple organs. Surveillance to facilitate the early detection and treatment of malignancies is extremely important. CASE REPORT: A 31-year-old male presented with a 10 cm left lobe thyroid gland mass. After fine needle aspiration a left hemithyroidectomy was performed, which demonstrated a minimally invasive follicular thyroid carcinoma (FTC, stage pT3a) and microscopic classical papillary thyroid carcinoma (PTC) in the background of about 50 separate adenomatous nodules (0.2-5 mm). Immunostaining showed loss of PTEN protein in the minimally invasive FTC and in all of the nodules tested, with uninvolved parenchyma serving as an internal control. Kaiser Permanente Northern California (KPNC) Hereditary Cancer Panel, testing for 62 genes, was performed and showed germline mutations in PTEN and RecQ like helicase 4 (RECQL4) genes. Completion thyroidectomy subsequently performed demonstrated about 60 follicular cell-derived adenomatous nodules (0.3-10 mm). Genetic counseling and evaluation documented Cowden syndrome (CS) in the family. Thus, PHTS was confirmed. CONCLUSION: This report documents synchronous FTC and PTC in a background of multiple follicular adenomatous nodules with a novel RECQL4 mutation in an adult patient with PHTS. As such, documented the loss of PTEN protein in a thyroid gland affected by multiple adenomatous nodules aided in diagnosing PHTS.

Synchronous Basal Cell Carcinoma and Squamous Cell Carcinoma of Nasal Vestibule With Novel Unique Variants Identified by Whole-exome Sequencing.

BACKGROUND/AIM: It is estimated that nonmelanoma skin cancer (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), affects more than 3 million Americans each year. Translation of next-generation sequencing (NGS) data into identification of new potential targets for therapeutic applications may be helpful. Whole-exome sequencing (WES) is a widely used NGS method that involves sequencing the protein-coding regions of the genome. CASE REPORT: We report a case of a 65-year-old female smoker who was found to have two 6 mm lesions in her left nasal vestibule. Biopsies demonstrated synchronous BCC and SCC. The patient underwent surgical excision of both cancers with safe margins followed by plastic reconstruction. WES was performed on both cancers and 16 alterations including BRCA2 (p.P389S), FAM5C (S420L), KMT2A (P855L), and SMO (L412F), as unique for BCC, and 4 alterations including TP53 (p.H179Q) and CDKN2A (p.P114L), as unique for SCC, were identified. CONCLUSION: We report the first documented case with unique genetic alterations in two distinct and synchronous skin BCC and SCC arising from the same nasal vestibule of a patient. This adds to the growing field of data regarding genetic variants in characterizing malignancies and potentially for targeted therapies.

Sulfatase-2 Regulates Liver Fibrosis through the TGF-ß Signaling Pathway.

Transforming growth factor-ß (TGF-ß) activates hepatic stellate cells (HSCs), which drive liver fibrosis via the production and deposition of extracellular matrix (ECM). We aimed to elucidate the mechanistic role of sulfatase-2 (SULF2) in liver fibrosis. To this end, we induced liver fibrosis in wild-type (WT) and SULF2 knockout (Sulf2-KO) mice (6-8 weeks-old) via bile duct ligation (BDL), intraperitoneal injection of carbon tetrachloride (CCl4) or thioacetamide (TAA). The levels of fibrosis in the liver sections were assessed via Sirius red and Masson's trichrome staining, immunohistochemistry and immunoblotting for α-smooth muscle actin (α-SMA) and hydroxyproline. To evaluate the interaction between TGF-ß and SULF2, we transfected human HSCs with scrambled control shRNA and shRNA constructs targeting SULF2 and measured α-SMA expression following treatment with TGF-ß1 ligand. We show here that knockout of SULF2 significantly decreases collagen content, as well as bands of bridging fibrosis, as demonstrated by Sirius red, Masson's trichrome and α-SMA staining after BDL, CCl4 and TAA injection in Sulf2-KO versus WT mice. In all three models of liver fibrosis, we observed significantly lower levels of hydroxyproline in the Sulf2-KO mice compared to the WT mice. HSCs with reduced levels of SULF2 failed to significantly express α-SMA and collagen type I following treatment with TGF-ß1. Furthermore, SULF2 co-localizes with TGFBR3 and the in vitro knockdown of SULF2 in HSCs decreases the release of TGF-ß1 from TGFBR3. Together, these data suggest that SULF2 regulates liver fibrosis via the TGF-ß signaling pathway. Pharmacologic inhibition of SULF2 may represent a novel therapeutic approach to improve liver fibrosis.

Role of Yes-associated Protein-1 in Gastrointestinal Cancers and Hepatocellular Carcinoma.

Yes-associated protein-1 (YAP1) is a potent transcriptional co-activator and functions as an important downstream effector of the Hippo signaling pathway, which is key to regulating cell proliferation, apoptosis, and organ growth. YAP1 has been implicated as an oncogene for various human cancers including gastrointestinal cancers and hepatocellular carcinoma (HCC). YAP1 promotes tumorigenesis and cancer progression by multiple mechanisms, such as by promoting malignant phenotypes, expanding cancer stem cells, and inducing epithelial-mesenchymal transition. YAP1 overexpression or its activated forms are associated with advanced pathological grades and poor prognosis of cancer, and therefore targeting YAP1 may open a fertile avenue for cancer therapy. In this review, we summarize the recent evidence regarding the role of YAP1 in the carcinogenesis of gastrointestinal cancers and HCC.

Ovarian Serous Carcinoma With a Novel HSP90AB1 Mutation in a Patient With Synchronous Primary Fallopian Tube Serous Carcinoma.

BACKGROUND/AIM: Ovarian carcinoma is the fifth leading cause of cancer-related deaths in women in the United States. Serous papillary carcinoma is the most common histological type of ovarian carcinoma that often goes undetected until it has spread within the pelvis and abdomen leading to poor prognosis. Translation of next-generation sequencing (NGS) technology into personalized medicine and identification of new potential targets for therapeutic applications may be helpful. CASE REPORT: We report a case of a 59-year-old female who initially presented in the emergency department with increasing abdominal girth, and bloating. Computed tomography showed ascites and omental and pelvic masses. Fine needle biopsy of the omental mass showed high-grade papillary adenocarcinoma consistent with high-grade ovarian serous carcinoma. She was treated with chemotherapy followed by debulking surgery. Primary ovarian serous carcinoma and synchronous primary fallopian tube serous carcinoma with multiple leiomyomas were identified in the surgical specimen. Pleural biopsy was also positive for carcinoma. NGS and programmed death-ligand 1 (PD-L1) expression testing were performed in the ovarian serous carcinoma. The results showed mutations of breast cancer type 1 (BRCA1) and type 2 (BRCA2), tumor protein p53 (TP53) (c.524G>A at pR175H), and heat shock protein 90 alpha family class B member 1 (HSP90AB1) (p.R456C), as well as low RNA expression score of PD-L1. CONCLUSION: Identification of these mutations and PD-L1 abnormality at the diagnosis of ovarian carcinoma may shed light for clinicians to provide targeted therapy with poly (ADP-ribose) polymerase (PARP) inhibitors and immune checkpoint inhibitors for ovarian serous carcinoma. This is the first documented case of ovarian serous carcinoma to have found a HSP90AB1 (p.R456C) mutation.

Cytologic features of hepatic YAP1-TFE3 rearranged epithelioid hemangioendothelioma.

Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor of intermediate malignancy, often with indolent behavior. Though most cases have a characteristic WWTR1-CAMTA1 gene fusion, a subtype of EHE with YAP1-TFE3 fusions and a distinct morphology has recently been described histologically, but no cases of YAP1-TFE3 EHE have been described in the cytology literature. We herein report on a case of YAP1-TFE3 fusion associated EHE diagnosed on fine-needle aspiration and core biopsy of a liver mass in an 18-year-old male patient who presented with synchronous lung and liver involvement. We also discuss the differential diagnosis of EHE on cytology specimens.