A thyroid EIF1AX story: how clinical, cytologic, and molecular surveillance led to appropriate management.

INTRODUCTION: Indeterminate thyroid cytology diagnoses are associated with intermediate risks of malignancy. Application of molecular testing (MT) to indeterminate specimens provides additional diagnostic and prognostic information. While a positive or suspicious MT result may prompt surgery, a negative MT result is associated with a low probability of cancer or noninvasive follicular thyroid neoplasm with papillary-like nuclear features and approximates that of a benign cytology diagnosis. Furthermore, ThyroSeq v3 MT has a "currently negative" result for findings with the probability of cancer or noninvasive follicular thyroid neoplasm with papillary-like nuclear feature that is slightly greater than that for the negative ThyroSeq v3 MT result but less than 10%, suggesting active surveillance. In this report, we discuss a case of a patient for whom clinical, cytologic, and molecular surveillance led to timely surgery and management. CLINICAL DETAILS: A 53-year-old man with a thyroid isthmus nodule had a fine-needle aspiration cytology diagnosis of atypia of undetermined significance and a subsequent ThyroSeq v3 MT, which revealed an EIF1AX mutation and a "currently negative" MT result. Surveillance with additional fine-needle aspiration samples demonstrated concerning genomic alterations (fluctuating EIF1AX allelic frequency and a non-V600E BRAF mutation), culminating in the conversion to a positive MT result 3 years later. Resection revealed an encapsulated noninvasive, oncocytic solid subtype of papillary thyroid carcinoma with increased mitotic activity. CONCLUSION: The case is notable for clinical, cytologic, and molecular surveillance demonstrating sequential pathologic alterations in an indeterminate thyroid nodule with EIF1AX mutation, leading to timely resection of the neoplasm before invasion manifested.

Prognostic Indicators of EIF1AX-Mutated Thyroid Tumor Malignancy and Cancer Aggressiveness.

The risk of malignancy (ROM) of EIF1AX-mutated thyroid nodules has been theorized to be contingent on the position of the mutation within the gene and the presence of co-existing mutations. However, due to EIF1AX's low mutation frequency, sample sizes currently reported in the literature are too diminutive to appraise the clinical utility of molecular diagnostic testing. The objective of this study was to elucidate prognostic indicators of EIF1AX-mutated thyroid tumors and cancer aggressiveness by examining a large cohort of cytologically indeterminate thyroid nodules (CITNs) that underwent molecular testing and subsequent surgical resection. This is a multicenter study involving 764 subtotal and total thyroidectomy patients that underwent preoperative molecular testing at two quaternary care hospitals. A five-year retrospective review was performed on the 42 charts of patients that opted for surgery following a positive EIF1AX mutation on ThyroseqV3 results from January 2018 to May 2022. Patient demographics, cytopathology results, molecular testing results, and postoperative histopathology were reviewed. Of the 42 surgically resected nodules that harbored an EIF1AX mutation, 16 (38.1%) were benign, six (14.3%) were non-invasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTPs) or well-differentiated thyroid neoplasms of uncertain malignant potential (WDT-UMPs), and 20 (47.6%) were malignant. An isolated EIF1AX mutation conferred a ROM of 47.6%, whereas the ROM for nodules with at least one additional molecular alteration was 72.7%. The ROM increased to 100% for nodules with at least one additional molecular alteration and the A113_splice site mutation. Six malignant nodules were aggressive, with five having variegated components of poorly differentiated thyroid carcinoma (PDTC). EIF1AX-mutated thyroid nodules are more susceptible to malignancy in the presence of the A113_splice site mutation and when co-mutated with RAS and/or TP53. This deleterious amalgam is associated with aggressive disease and renders these nodules PDTC. A preoperative molecular test finding of an EIF1AX mutation can be a useful tool for thyroid specialists to optimize clinical management.

EIF1AX mutation in thyroid tumors: a retrospective analysis of cytology, histopathology and co-mutation profiles.

BACKGROUND: The EIF1AX mutation has been identified in various benign and malignant thyroid lesions, with a higher prevalence in poorly differentiated thyroid carcinoma (PDTC) and anaplastic thyroid carcinoma, especially when combined with RAS or TP53 mutation. However, data and clinical significance of EIF1AX mutations in thyroid nodules is still limited. We investigated the prevalence of EIF1AX mutations and co-mutations in cytologically indeterminate thyroid nodules at our institution. METHODS: A 5-year retrospective analysis was performed on surgically resected thyroid nodules with identified EIF1AX mutations on molecular testing with ThyroseqV3®. Mutation type and presence of co-mutations were correlated with histopathologic diagnosis and clinical characteristics. Histopathology diagnoses were subsequently categorized as benign, borderline, malignant or aggressive malignant (≥ 10% PDTC component). Chi-square test was used to compare the malignancy associations of the: 1) A113_splice mutation compared to non-A113_splice mutations 2) singular A113_splice mutations compared to singular non-A113_splice mutations. Fisher's Exact Test was used to determine the association of A113_splice mutation with aggressive malignancies compared to non-A113_splice mutations. A p value of 0.05 or less was considered statistically significant. RESULTS: Out of 1583 patients who underwent FNA, 621 had further molecular testing. 31 cases (5%) harbored EIF1AX mutations. Of these cases, 12 (38.7%) were malignant, 2 (6.5%) were borderline, and 17 (55%) were benign. 4/31 cases (13%) were aggressive malignant (≥ 10% PDTC component). The most prevalent mutation was the A113_splice mutation at the junction of intron 5 and exon 6 (48%). All other mutations, except one, were located at the N-terminal in exon 2. 7/31 cases (22.6%) harbored ≥ 1 co-mutation(s), including 4 RAS, 3 TP53, 1 TERT and 1 PIK3CA, with 86% of them being malignant. All 4 nodules with RAS co-mutations were malignant including one PDTC. CONCLUSION: Our study reports the largest cohort of EIF1AX mutations in Bethesda III/IV FNA samples with surgical follow-up to our knowledge. The presence of the EIF1AX mutation confers a 45.2% risk of malignancy (ROM) or borderline after surgery. However, the coexistence of EIF1AX mutations with other driver mutations such as RAS, TERT or TP53 conferred an 86% ROM. While 55% of thyroid nodules were benign at the time of surgery, the possible malignant transformation of these nodules, had they not been resected, is unknown. Finally, 13% of the nodules with EIF1AX mutations were aggressive with a significant PDTC component. These findings can further aid in clinical decisions for patients with thyroid nodules.

Correlation between BAP1 Localization, Driver Mutations, and Patient Survival in Uveal Melanoma.

Uveal melanoma (UM) is an uncommon but highly aggressive ocular malignancy. Poor overall survival is associated with deleterious BAP1 alterations, which frequently occur with monosomy 3 (LOH3) and a characteristic gene expression profile. Tumor DNA from a cohort of 100 UM patients from Moorfields Biobank (UK) that had undergone enucleation were sequenced for known UM driver genes (BAP1, SF3B1, EIF1AX, GNAQ, and GNA11). Immunohistochemical staining of BAP1 and interphase FISH for chromosomes 3 and 8 was performed, and cellular localization of BAP1 was correlated with BAP1 mutations. Wildtype (WT) BAP1 staining was characterized by nBAP1 expression with <10% cytoplasmic BAP1 (cBAP1). Tumors exhibited heterogeneity with respect to BAP1 staining with different percentages of nBAP1 loss: ≥25% loss of nuclear BAP1 (nBAP1) was superior to chr8q and LOH3 as a prognostic indicator. Of the successfully sequenced UMs, 38% harbored oncogenic mutations in GNA11 and 48% harbored mutations in GNAQ at residues 209 or 183. Of the secondary drivers, 39% of mutations were in BAP1, 11% were in EIF1AX, and 20% were in the SF3B1 R625 hotspot. Most tumors with SF3B1 or EIF1AX mutations retained nuclear BAP1 (nBAP1). The majority of tumor samples with likely pathogenic BAP1 mutations, regardless of mutation class, displayed ≥25% loss of nBAP1. This included all tumors with truncating mutations and 80% of tumors with missense mutations. In addition, 60% of tumors with truncating mutations and 82% of tumors with missense mutations expressed >10% cBAP1.

An unusual familial Xp22.12 microduplication including EIF1AX: A novel candidate dosage-sensitive gene for premature ovarian insufficiency.

We report on the results of array-CGH and Whole exome sequencing (WES) studies carried out in a Tunisian family with 46,XX premature ovarian insufficiency (POI). This study has led to the identification of a familial Xp22.12 tandem duplication with a size of 559.4 kb, encompassing only three OMIM genes (RPS6KA3, SH3KBP1and EIF1AX), and a new heterozygous variant in SPIDR gene: NM_001080394.3:c.1845_1853delTATAATTGA (p.Ile616_Asp618del) segregating with POI. Increased mRNA expression levels were detected for SH3KBP1 and EIF1AX, while a normal transcript level for RPS6KA3 was detected in the three affected family members, explaining the absence of intellectual disability (ID). To the best of our knowledge, this is the first duplication involving the Xp22.12 region, reported in a family without ID, but rather with secondary amenorrhea (SA) and female infertility. As EIF1AX is a regulatory gene escaping X-inactivation, which has an extreme dosage sensitivity and highly expressed in the ovary, we suggest that this gene might be a candidate gene for ovarian function. Homozygous nonsense pathogenic variants of SPIDR gene have been reported in familial cases in POI. It has been suggested that chromosomal instability associated with SPIDR molecular defects supports the role of SPIDR protein in double-stranded DNA damage repair in vivo in humans and its causal role in POI. In this family, the variant (p.Ile616_Asp618del), present in a heterozygous state, is located in the domain that interacts with BLM and might disrupt the BLM binding ability of SPIDR protein. These findings strengthen the hypothesis that the additional effect of this variant could lead to POI in this family. Although the work represents the first evidence that EIF1AX duplication might be responsible for POI through its over-expression, further functional studies are needed to clarify and prove EIF1AX involvement in POI phenotype.

Patient with multiple genetically distinct thyroid nodules including papillary thyroid carcinoma harboring novel YWHAG-BRAF fusion.

Next-generation sequencing (NGS) analysis of thyroid samples aids in risk stratification of cytologically indeterminate nodules and contributes to our understanding of molecular mechanisms in thyroid neoplasia. Several genes, including BRAF, RAS, and EIF1AX, are known to play a role in thyroid tumorigenesis. Here we report a case of papillary thyroid carcinoma (PTC) in which a single lesion harbored a novel YWHAG-BRAF fusion and EIF1AX mutation and displayed mixed morphological findings. The patient is a 74-year-old female with multiple incidentally discovered thyroid nodules, two of which were sampled by ultrasound-guided fine needle aspiration (FNA). Cytologic diagnosis for both nodules was suspicious for follicular neoplasm (Bethesda Category IV). NGS testing of one nodule detected a novel in-frame YWHAG-BRAF fusion and a concurrent EIF1AX A113 splice mutation. The subsequent surgical resection specimen showed that this nodule exhibited two distinct morphologic patterns, conventional (classical) type and follicular variant (FV) of PTC, which were sharply demarcated and were found to harbor unique genetic alterations. Of note, this is the first report of BRAF activation through novel rearrangement with a gene encoding a 14-3-3 protein as a pathogenic factor, which underlines its significance both as a prognostic measurement and as a therapeutic target.

Clinicopathological features and outcomes of thyroid nodules with EIF1AX mutations.

EIF1AX gene mutations are reported in both benign and malignant thyroid tumors, with unclear outcomes when detected preoperatively. The aim of this study was to determine the features and outcomes of thyroid nodules with various types of mutation identified in cytologic (fine-needle aspiration) samples on preoperative ThyroSeq testing and with surgical outcomes. In this single-institution retrospective study of 31 consecutive patients, 77% were female and nodule size ranged from 1.5 to 9.4 cm with widely varying cytologic and TI-RADS ultrasound categorizations. Among two main mutational hotspots, 55% were located in exon 2 and 45% at the intron 5/exon 6 splice site. On histology, 45% of -positive nodules were cancer/noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) including 19% encapsulated follicular variant papillary thyroid carcinoma, 10% follicular carcinoma, 10% anaplastic carcinoma (ATC), and 7% NIFTP. Almost half (48%) of patients had one or more coexisting mutations, most frequently RAS. The prevalence of cancer/NIFTP was 80% for mutation with coexisting molecular alteration vs 13% with an isolated mutation (P = 0.0002). Cancer probability was associated with mutation type and was 64% for splice-site mutation and 29% for non-splice mutation (P = 0.075). All 3 nodules with EIF1AX+RAS+TERT+TP53 mutations were ATC. In summary, in this study, all nodules with an isolated non-splice mutation were benign, one-third of those with an isolated splice mutation were cancer, and most nodules with coexisting with RAS or other alterations were malignant. These findings suggest that clinical management decisions for patients with EIF1AX-mutant nodules should consider both the type of mutation and its co-occurrence with other genetic alterations.

Long noncoding RNA EIF1AX-AS1 promotes endometrial cancer cell apoptosis by affecting EIF1AX mRNA stabilization.

Long noncoding RNAs (lncRNAs) have been found to play an important role in the occurrence and development of endometrial carcinoma (EC). Here, using RNA sequencing analysis, we systemically screened and identified the lncRNA eukaryotic translation initiation factor 1A, X-linked (EIF1AX)-AS1, which is aberrantly downregulated in clinical EC tissues and closely correlated with tumor type. EIF1AX-AS1 markedly inhibited EC cell proliferation and promoted apoptosis in vitro and in vivo. Mechanistically, EIF1AX-AS1 interacts with EIF1AX mRNA and poly C binding protein 1 (PCBP1), which promote EIF1AX mRNA degradation. Intriguingly, by interacting with internal ribosome entry site-related protein Y-box binding protein 1 (YBX-1), EIF1AX promotes c-Myc translation through the internal ribosome entry site pathway. c-Myc promotes EIF1AX transcription and thus forms a feed-forward loop to regulate EC cell proliferation. Taken together, these data reveal new insights into the biology driving EC proliferation and highlights the potential of lncRNAs as biomarkers for prognosis and future therapeutic targets for cancer.

Lnc5926 is essential for early embryonic development in goats through regulation of ZSCAN4 and EIF1AX.

Long noncoding RNAs (lncRNAs) are abundant in mammalian genomes and have been found to play important roles in many biological events. However, the mechanism by which lncRNAs regulate embryonic development remains to be fully elucidated. Here, we investigated the function of the lncRNA, TCONS_00135926 (referred to as lnc5926), through knockdown and overexpression experiments in goat early embryos. Lnc5926 expression at the eight-cell embryonic stage was significantly higher than that at other stages, which was consistent with the pattern of embryonic genome activation (EGA) gene expression. The blastocyst rate after lnc5926 knockdown in eight-cell embryos was significantly lower than that in the control group (0.2% vs. 17.1%, p < 0.05), whereas the cleavage rate was not affected (71.9% vs. 75.1%, p ˃ 0.05). After knockdown or overexpression of lnc5926 in embryos, we measured expression levels of the potential target genes, STAM, HACD1, UBL5, MIOX, ELF1, and the key EGA genes, ZSCAN4 and EIF1AX. Only ZSCAN4 and EIF1AX were significantly downregulated after lnc5926 knockdown, and this effect was reversed by lnc5926 overexpression. We conclude that lnc5926 plays an essential role in early embryonic development in goats by regulating expression of EGA-associated genes.

The Sex Differences in Uveal Melanoma: Potential Roles of EIF1AX, Immune Response and Redox Regulation.

BACKGROUND: Uveal melanoma (UVM) is a rare cancer that shows sex difference in incidence and survival, with little previous report for the underlying mechanism. METHODS: This study used the SEER data (1974-2016) for an age-dependent analysis on sex difference in UVM, and further used the TCGA-UVM genomics dataset for analyzing the differential gene expression profiles in tumors from men and women. RESULTS: Our results demonstrate a sex difference in older age (≥40 years) but not in younger patients, with men exhibiting a higher incidence rate than women. However, younger women have shown a continuous increasing trend since 1974. Examining the 11 major oncogenes and tumor suppressors in UVM revealed that EIF1AX showed a significant sex difference in mRNA accumulation and copy number variation, with female tumors expressing higher levels of EIF1AX and exhibiting more variations in copy numbers. EIF1AX mRNA levels were significantly inversely correlated with EIF1AX copy numbers in female tumors only, but not in male tumors. Differential gene expression analysis at the whole genomic level identified a set of 92 protein-coding and 16 RNA-coding genes which exhibited differential expression in men and women (fold of change cutoff at 1.7, adjusted p value < 0.05, FDR < 0.05). Network analysis showed significant difference in immune response and in disulfide bond formation, with EGR1/EGR2 and PDIA2 genes as regulators for immune response and disulfide bond formation, respectively. The melanocortin pathway which is linked to both melanin synthesis and obesity seems to be altered with unclear significance, as the sex difference in POMC, DCT/TYRP2, and MRAP2 was observed but with no clear direction. CONCLUSION: This study reveals possible mechanisms for the sex difference in tumorigenesis of UVM which has potentials for better understanding and prevention of UVM.

Characterization and Clinical Significance of EIF1AX Mutations and Co-Mutations in Cytologically Indeterminate Thyroid Nodules: A 5-Year Retrospective Analysis.

OBJECTIVE: Mutations in the EIF1AX gene have been recently detected in a small percentage of benign and malignant thyroid lesions. We sought to investigate the prevalence and clinical significance of EIF1AX mutations and co-mutations in cytologically indeterminate thyroid nodules at our institution. MATERIALS AND METHODS: A 5-year retrospective analysis was performed on thyroid nodules with a cytologic diagnosis of Bethesda category III or IV, which had undergone testing by our in-house next generation sequencing panel. Surgically resected nodules with EIF1AX mutations were identified, and mutation type and presence of co-mutations were correlated with histopathologic diagnosis. RESULTS: 41/904 (4.5%) cases overall and 26/229 (11.4%) surgically resected nodules harbored an EIF1AX mutation. The most common histologic diagnoses were follicular thyroid carcinoma and follicular variant of papillary thyroid carcinoma. 11/26 (42.3%) of nodules had isolated EIF1AX mutation. Comutations were found in RAS (12/26; 46.2%), TERT (5/26; 19.2%) and TP53 (2/26; 7.7%). EIF1AX mutation alone conferred a 36.4% risk of malignancy (ROM) and 54.5% ROM or noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), while the ROM was significantly higher in nodules with concurrent RAS (71.4%), TERT, TP53 and RAS+TERT (100%) mutations. CONCLUSION: EIF1AX mutations occur in benign and malignant follicular thyroid neoplasms. In our cohort, the majority of mutations occurred at the splice acceptor site between exons 5 and 6. Importantly, the coexistence of EIF1AX mutations with other driver pathogenic mutations in RAS, TERT and TP53 conferred a 100% ROM or NIFTP, indicating that such nodules require surgical removal.

Somatic Mutations in the BRAF, KRAS, NRAS, EIF1AX, and TERT Genes: Diagnostic Value in Thyroid Neoplasms.

The feasibility of using molecular genetic markers associated with thyroid neoplasms and more aggressive course of the disease is now actively studied. We analyzed the diagnostic value of somatic mutations in the hot spots of BRAF, KRAS, KRAS, EIF1AX, and TERT genes in histological material from 153 patients with thyroid gland neoplasms. BRAF mutations (exon 15, codon area 600-601) were found in 54 patients, NRAS mutations (exon 3, codon 61) were detected in 12 patients; mutations KRAS, TERT, and EIF1AX genes were not detected.

Emerging Therapeutic Opportunities Based on Current Knowledge of Uveal Melanoma Biology.

Uveal Melanoma (UM) is a rare and malignant intraocular tumor with dismal prognosis. Despite the efficient control of the primary tumor by radiation or surgery, up to 50% of patients subsequently develop metastasis, mainly in the liver. Once the tumor has spread from the eye, the treatment is challenging and the median survival is only nine months. UM represents an intriguing model of oncogenesis that is characterized by a relatively homogeneous histopathological architecture and a low burden of genetic alterations, in contrast to other melanomas. UM is driven by recurrent activating mutations in Gαq pathway, which are associated with a second mutation in BRCA1 associated protein 1 (BAP1), splicing factor 3b subunit 1 (SF3B1), or eukaryotic translation initiation factor 1A X-linked (EIF1AX), occurring in an almost mutually exclusive manner. The monosomy of chromosome 3 is also a recurrent feature that is associated with high metastatic risk. These events driving UM oncogenesis have been thoroughly investigated over the last decade. However, no efficient related therapeutic strategies are yet available and the metastatic disease remains mostly incurable. Here, we review current knowledge regarding the molecular biology and the genetics of uveal melanoma and highlight the related therapeutic applications and perspectives.

The role of EIF1AX in thyroid cancer tumourigenesis and progression.

PURPOSE: The EIF1AX gene was recently described as a new thyroid cancer-related gene. Its mutations were mainly reported in poorly differentiated (PDTC) and anaplastic thyroid cancers (ATC), but also in well-differentiated thyroid cancer (WDTC) and in benign thyroid lesions, although less frequently. Our aim was to address whether EIF1AX mutations are present in the different stages of thyroid tumourigenesis (from hyperplasia to well-differentiated and to poorly differentiated/undifferentiated lesions), and to clarify its role in this process. METHODS: We analysed the EIF1AX gene in a series of 16 PDTC and ATC cases with coexistent well-differentiated regions and/or benign lesions. In EIF1AX mutant cases we also assessed the presence of RAS genes mutations. RESULTS: We identified the mutation p.Ala113_splice in the EIF1AX gene in two PDTCs (neither present in the well-differentiated counterparts nor in the benign areas). One of these tumours also evidenced the mutation p.Glu61Arg in NRAS in both poorly and well-differentiated regions, further suggesting that the EIF1AX p.Ala113_splice mutation could be associated with tumoural progression. In another patient we did not find any EIF1AX alteration in the PDTC component, but we detected the EIF1AX p.Gly6_splice mutation in the PTC area (both regions were RAS wild-type). This mutation did not seem to be related with dedifferentiation. CONCLUSIONS: According to our results, distinct mutations on EIF1AX may be related to different phenotypes/behaviours. Despite being a small series, which reflects the difficulty in retrieving PDTC and ATC surgical samples with well-differentiated and/or benign areas, our study may provide new insights into thyroid cancer tumourigenesis and dedifferentiation.

Cancer-Associated Eukaryotic Translation Initiation Factor 1A Mutants Impair Rps3 and Rps10 Binding and Enhance Scanning of Cell Cycle Genes.

Protein synthesis is linked to cell proliferation, and its deregulation contributes to cancer. Eukaryotic translation initiation factor 1A (eIF1A) plays a key role in scanning and AUG selection and differentially affects the translation of distinct mRNAs. Its unstructured N-terminal tail (NTT) is frequently mutated in several malignancies. Here we report that eIF1A is essential for cell proliferation and cell cycle progression. Ribosome profiling of eIF1A knockdown cells revealed a substantial enrichment of cell cycle mRNAs among the downregulated genes, which are predominantly characterized by a lengthy 5' untranslated region (UTR). Conversely, eIF1A depletion caused a broad stimulation of 5' UTR initiation at a near cognate AUG, unveiling a prominent role of eIF1A in suppressing 5' UTR translation. In addition, the AUG context-dependent autoregulation of eIF1 was disrupted by eIF1A depletion, suggesting their cooperation in AUG context discrimination and scanning. Importantly, cancer-associated eIF1A NTT mutants augmented the eIF1A positive effect on a long 5' UTR, while they hardly affected AUG selection. Mechanistically, these mutations diminished the eIF1A interaction with Rps3 and Rps10 implicated in scanning arrest. Our findings suggest that the reduced binding of eIF1A NTT mutants to the ribosome retains its open state and facilitates scanning of long 5' UTR-containing cell cycle genes.

Detection of mutations in SF3B1, EIF1AX and GNAQ in primary orbital melanoma by candidate gene analysis.

BACKGROUND: Ocular melanoma is a rare but often deadly malignancy that arises in the uvea (commonest primary site), conjunctiva or the orbit. Primary orbital melanoma (POM) is exceedingly rare, with approximately 60 cases reported to date. Despite recent advances in our understanding of the genetics of primary uveal and conjunctival melanomas, this information is lacking for POM. METHODS: DNA was extracted from 12 POM tissues, with matched germline DNA (where available). MLPA was conducted to detect chromosomal alterations and Sanger sequencing used to identify point mutations in candidate melanoma driver genes (BRAF, NRAS, KRAS, GNA11, GNAQ), and other genes implicated in melanoma prognosis (EIF1AX, SF3B1). Immunohistochemistry was performed to analyse BAP1 nuclear expression. RESULTS: MLPA detected copy number alterations in chromosomes 1p, 3, 6 and 8. Sequencing of melanoma driver genes revealed GNAQ (p.Q209L) mutations in two samples; although it is possible that these samples represent extraocular spread of an occult uveal melanoma. A recurrent mutation in SF3B1 (p.R625H) was observed in indolent, but not aggressive, tumours; a mutation in EIF1AX (p.N4S) was detected in one patient with non-aggressive disease. CONCLUSIONS: EIF1AX and SF3B1 mutations appear have a role in determining the clinical course of POM and detection of these changes could have clinical significance. Further in depth analysis of this rare group using differing 'omic technologies will provide novel insights into tumour pathogenesis.

TERT, HRAS, and EIF1AX Mutations in a Patient with Follicular Adenoma.

BACKGROUND: Molecular markers are increasingly used as diagnostic tools in the management of thyroid nodules. There is a paucity of studies evaluating the prevalence of molecular markers in benign lesions. PATIENT FINDINGS: A 68-year-old woman with hypothyroidism presented with a right thyroid nodule, which was atypia of undetermined significance on cytology. The fine-needle aspirate of the nodule was examined with next-generation sequencing and found to harbor a C228T mutation in the TERT gene, a Q61R mutation in the HRAS gene, and an A113_splice mutation in the EIF1AX gene. Right thyroid lobectomy was performed, with final pathology showing follicular adenoma. All three mutations detected in the original fine-needle aspirate specimen were detected in the final surgical specimen as well. CONCLUSIONS: A rare case of TERT, HRAS, and EIF1AX mutations is reported in a patient with follicular adenoma. TERT promoter mutations may be an early genetic event in the molecular pathogenesis of follicular thyroid carcinoma.

EIF1AX Mutation in a Patient with Hürthle Cell Carcinoma.

The EIF1AX gene is a novel cancer gene that has been reported in the tumorigenesis of papillary thyroid carcinoma, follicular variant papillary thyroid carcinoma, and anaplastic thyroid carcinoma. A 71-year-old woman presented with a right thyroid mass, which was follicular neoplasm on cytology. The fine needle aspirate of the nodule was examined by next-generation sequencing and found to harbor EIF1AX and TP53 mutations. Right thyroid lobectomy was performed with final pathology showing Hürthle cell carcinoma with capsular and vascular invasion. We report an EIF1AX mutation in a patient found to have Hürthle cell carcinoma.

Intraventricular melanocytoma diagnosis confirmed by gene mutation profile.

Primary leptomeningeal melanocytic tumors (PLMTs) are rare. They usually arise along the spinal cord and at the skull base. Here we report on a patient with a very rare intraventricular melanocytoma. Histologically, a melanocytic tumor was clearly diagnosed. However, to make the uncommon diagnosis of an intraventricular melanocytoma, metastatic melanoma needed to be excluded. Next generation sequencing covering gene mutations that may occur in PLMTs and cutaneous melanoma was performed. The unique gene mutation profile detected, consisting of an activating CYSLTR2 L129Q mutation and EIF1AX G9R mutation and a lack of mutations in genes known to occur in metastatic melanoma (i.e. BRAF or NRAS) confirmed the diagnosis of an intraventricular melanocytoma. This case report is the second intraventricular melanocytoma published to date and demonstrates the value of applying novel genetic assays to make this diagnosis.

Integrative Analysis Identifies Four Molecular and Clinical Subsets in Uveal Melanoma.

Comprehensive multiplatform analysis of 80 uveal melanomas (UM) identifies four molecularly distinct, clinically relevant subtypes: two associated with poor-prognosis monosomy 3 (M3) and two with better-prognosis disomy 3 (D3). We show that BAP1 loss follows M3 occurrence and correlates with a global DNA methylation state that is distinct from D3-UM. Poor-prognosis M3-UM divide into subsets with divergent genomic aberrations, transcriptional features, and clinical outcomes. We report change-of-function SRSF2 mutations. Within D3-UM, EIF1AX- and SRSF2/SF3B1-mutant tumors have distinct somatic copy number alterations and DNA methylation profiles, providing insight into the biology of these low- versus intermediate-risk clinical mutation subtypes.