Oncocytic Adenoma Research Articles

A rare case report of hurthle cell adenoma mimicking malignancy

Thyroid lesions are the most common endocrine diseases, occurring in usually all age groups, though accurate diagnosis still remains a challenge, as due to oncocytic potentials of Thyroid cells leads to like indeterminate or suspicious diagnosis. Long standing benign Thyroid lesion shows atypical presentation suspicious to malignancy. Now a days with the help of WHO classification and available advanced diagnostic measures helping to confirm the diagnosis, avoiding overdiagnosis and wrong treatment. Hence this study review the importance of Histopathological study with coordination with immunohistochemistry (IHC) study, where suspicious thyroid malignant lesion finally diagnosed as benign Hurthle cell/ Oncocytic adenoma in Nodular Goitre.: 72 year old female presented huge neck swelling since one year, was reviewed in our departments of Pathology and ENT. Fine needle aspiration cytology (FNAC) features are suspicious of Malignancy, further Histopathological features were studied with co ordance of IHC study. FNAC features, which were suspicious of Malignancy were further studied with Histopathological and IHC studies diagnosed as Hurthle cell/ Oncocytic adenoma in Nodular Goitre. Histopathology remains the cornerstone for the diagnosis of thyroid oncocytic lesions and also in distinguishing between adenoma and carcinoma.

A Recognition System for Diagnosing Salivary Gland Neoplasms Based on Vision Transformer

Salivary gland neoplasms (SGNs) represent a group of human neoplasms characterized by a remarkable cyto-morphological diversity, which frequently poses diagnostic challenges. Accurate histological categorization of salivary tumors is crucial to make precise diagnoses and guide decisions regarding patient management. Within the scope of this study, a computer-aided diagnosis model utilizing Vision Transformer, a cutting-edge deep-learning model in computer vision, has been developed to accurately classify the most prevalent subtypes of SGNs. These subtypes include pleomorphic adenoma, myoepithelioma, Warthin's tumor, basal cell adenoma, oncocytic adenoma, cystadenoma, mucoepidermoid carcinoma and salivary adenoid cystic carcinoma. The dataset comprised 3046 whole slide images (WSIs) of histologically confirmed salivary gland tumors, encompassing nine distinct tissue categories. SGN-ViT exhibited impressive performance in classifying the eight salivary gland tumors, achieving an accuracy of 0.9966, an AUC value of 0.9899, precision of 0.9848, recall of 0.9848, and an F1-score of 0.9848. When compared to benchmark models, SGN-ViT surpassed them in terms of diagnostic performance. In a subset of 100 WSIs, SGN-ViT demonstrated comparable diagnostic performance to that of the chief pathologist while significantly reducing the diagnosis time, indicating that SGN-ViT held the potential to serve as a valuable computer-aided diagnostic tool for salivary tumors, enhancing the diagnostic accuracy of junior pathologists.

Psammoma bodies in thyroid: are they always indicative of malignancy? A multi-institutional study.

Traditionally, psammoma bodies (PB) have been considered as tale-tell evidence of papillary thyroid carcinoma (PTC) and are frequently encountered in classic and other subtypes of PTCs. However, the presence of PBs in the thyroid gland does not always indicate malignancy. The leading hypothesis on their origin suggests that PB are remnants of papillary structures that have undergone thrombosis, necrosis, and subsequent calcification. From January 2010 to May 2024, 26 patients with psammoma bodies associated with benign thyroid lesions, mainly thyroid follicular nodular disease (TFND), Hashimoto thyroiditis (HT), Graves' disease, and follicular adenomas, were found. The case cohort included 16 females and 10 males with a median age of 49.3years. The series included 12 TFND, two HT, and 12 follicular adenomas (11 out of 12 were oncocytic adenomas). Twenty-four out of 26 underwent total thyroidectomy. In 24 out of 26 cases, the entire lobes and parenchyma were included and serial cuts at multiple levels were performed in cases with PB but without any evidence of malignancy. Even though the detection of PB is associated with a malignant thyroid lesion, especially PTC and its subtypes, our multi-institutional series showed that in a minority PB can be found in a variety of benign thyroid lesions. Evaluation of the entire thyroid parenchyma at multiple levels is mandatory to exclude sub-centimeter papillary thyroid carcinoma.

EIF1AX mutation in thyroid nodules: a histopathologic analysis of 56 cases in the context of institutional practices.

EIF1AX mutation has been identified as a driver mutation for papillary thyroid carcinoma (PTC) by The Cancer Genome Atlas (TCGA) study. Subsequent studies confirmed this mutation in PTC and Anaplastic Thyroid Carcinoma (ATC) but also reported EIF1AX mutation in Follicular nodular disease (FND) and benign thyroid nodules. In this study, we review thyroid nodules with EIF1AX mutation from two institutions: a tertiary care hospital (YNHH, n = 22) and a major cancer referral center (MSKCC, n = 34) and report the varying histomorphology in the context of additional genetic abnormalities and institutional practices. Pathology diagnoses were reviewed according to the WHO 5th edition and correlated with the type of EIF1AX mutation and additional concurrent molecular alterations, if any. Most cases were splice site type mutations. Cases consisted of 9 FND, 7 follicular (FA) or oncocytic adenomas (OA), 2 non-invasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP) and 38 follicular-cell derived thyroid carcinomas. Of 8 cases with isolated EIF1AX mutation, 7 were FND, FA or OA (88%) and one was an oncocytic carcinoma (12%). Of 12 cases with EIF1AX and one additional molecular alteration, 9 (75%) were FND, FA or OA, 2 (17%) were NIFTPs and one (8%) was a poorly differentiated thyroid carcinoma. All 36 cases with EIF1AX mutation and molecular alterations were malignant (100%) and included TP53 and TERT promoter mutations associated with ATC (n = 8) and high-grade follicular cell-derived non-anaplastic carcinoma (HGC, n = 2). Isolated EIF1AX mutation was noted only in thyroid nodules seen at YNHH and were predominantly encountered in benign thyroid nodules including FND. Accumulation of additional genetic abnormalities appears to be progressively associated with malignant tumors.

Diagnostic Performance of Thyroid FNA: Experience of Belarusian National Referral Thyroid Cancer Center.

A fine-needle aspiration (FNA) biopsy is a basic procedure to verify the morphology of thyroid nodules. However, significant variations in the diagnostic performance of FNA, as well as fluctuations in the rate of malignancy (ROM) in different categories of the Bethesda System for Reporting Thyroid Cytopathology, have been discovered in many studies. The development and employment of additional molecular tests in daily clinical practice require an understanding of the prevalence and structure of thyroid malignancy in each category of the Bethesda system. Current research is a continuous retrospective cohort study of the results of the examination and treatment of 1652 patients with thyroid tumors who have undergone primary surgery in 2021 at a national referral thyroid cancer center. FNA diagnostic performance was studied by comparing cytological diagnoses with histological outcomes. The authors evaluated ROM in each Bethesda category and identified the tumors representing a diagnostic pitfall. The overall ROM was 72.4%. When considering ROM in each Bethesda category, it was 16.7% in Bethesda I, 10.1% in Bethesda II, 23.0% in Bethesda IV, 74.8% in Bethesda V, 99.4% in Bethesda VI. The false-positive rate was 65.0%, false negative-0.67%. Follicular and oncocytic adenomas, as well as the follicular variant of papillary thyroid cancer, were the most troublesome entities for patients' management. ROM was comparable to the values implied by the Bethesda system. Follicular tumors were the main source of high false-positive rates. This necessitates the refinement of existing tests and the development of new diagnostic tests to overcome the abovementioned problems.

Adrenal Oncocytoma: A Rare Tumor with Conflicting Imaging Features.

Oncocytic adenomas are rare benign tumors that typically originate in organs such as the kidneys, thyroid, parathyroid, salivary glands, or pituitary gland. Oncocytic adenoma of the adrenal gland is extremely rare. It often shows heterogeneous, nonspecific features on anatomic imaging, as well as high 18F-FDG avidity despite its benign nature. The definitive diagnosis relies on histopathologic examination, including immunohistochemistry. We present an incidentally detected benign adrenal oncocytic adenoma with intense 18F-FDG uptake mimicking sinister pathologies.

Molecular Pathology of Thyroid Tumors: Essential Points to Comprehend Regarding the Latest WHO Classification.

In 2022, the new WHO Classification of Endocrine and Neuroendocrine Tumors, Fifth Edition (beta version) (WHO 5th), was published. Large-scale genomic analyses such as The Cancer Genome Atlas (TCGA) have revealed the importance of understanding the molecular genetics of thyroid tumors. Consequently, the WHO 5th was fundamentally revised, resulting in a systematic classification based on the cell of origin of tumors and their clinical risk. This paper outlines the following critical points of the WHO 5th. 1. Genetic mutations in follicular cell-derived neoplasms (FDNs) highlight the role of mutations in the MAP kinase pathway, including RET, RAS, and BRAF, as drivers of carcinogenesis. Differentiated thyroid cancers such as follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) have specific genetic alterations that correlate with morphological classifications: RAS-like tumors (RLTs) and BRAF p.V600E-like tumors (BLTs), respectively. 2. The framework for benign lesions has been revised. The WHO 5th introduces a new category: "developmental abnormalities". Benign FDNs comprise "thyroid follicular nodular disease", follicular thyroid adenoma (FTA), FTA with papillary architecture, and oncocytic adenoma (OA). "Hürthle cell adenoma/carcinoma" is renamed oncocytic adenoma/carcinoma of the thyroid (OA/OCA), which can be distinguished from FTA/FTC by its unique genetic background. 3. Low-risk tumors include NIFTP, TT-UMP, and HTT, and they have an extremely low malignant potential or an uncertain malignant potential. 4. PTC histological variants are reclassified as "subtypes" in the WHO 5th. 5. The concept of high-grade carcinomas is introduced, encompassing poorly differentiated thyroid carcinoma (PDTC), differentiated high-grade thyroid carcinoma (DHGTC), and high-grade medullary thyroid carcinoma (MTC). 6. Squamous cell carcinoma is included in anaplastic thyroid carcinoma (ATC) in the WHO 5th due to their shared genetic and prognostic features. 7. Other miscellaneous tumors are categorized as salivary-gland-type carcinomas of the thyroid, thyroid tumors of uncertain histogenesis, thymic tumors within the thyroid, and embryonal thyroid neoplasms. The WHO 5th thus emphasizes the importance of classifying tumors based on both genetic abnormalities and histomorphology. This approach aids in achieving accurate pathological diagnosis and facilitates the early selection of appropriate treatment options, including molecular targeted therapies.

Critical appraisal of the WHO 2022 classification of thyroid cancer

The WHO Classification of Endocrine and Neuroendocrine Tumors, Fifth Edition, is a current publication that includes relevant revisions to the nomenclature, grading, and prognostication of endocrine tumors based on pathologic characteristics and molecular profile. Additional entities such as thyroid follicular nodular disease, follicular adenoma with papillary architecture, and oncocytic adenoma of the thyroid are included in the benign follicular cell-derived category. Fifth edition WHO has refined the spectrum of papillary thyroid carcinoma (PTC) by aligning invasive encapsulated follicular variant PTCs with follicular thyroid carcinomas. Follicular cell-derived differentiated thyroid carcinomas may also have high-grade features in the absence of morphologic dedifferentiation, and hence, differentiated thyroid carcinomas with high-grade features are now recognized as a distinct morphologic spectrum. The Ki-67 proliferation index reporting is required in all medullary thyroid carcinomas for grading.

Somatostatin Receptor Type 2 and Thyroid-Stimulating Hormone Receptor Expression in Oncocytic Thyroid Neoplasms: Implications for Prognosis and Treatment

Somatostatin receptor type 2 (SSTR2) and thyroid-stimulating hormone receptor (TSHR) display variable expression in primary thyroid tumors and have been implicated as theranostic targets. This study was designed to explore the differential expression of SSTR2 and TSHR in oncocytic (Hurthle cell) carcinoma (OC) vs oncocytic adenoma (OA). We performed a retrospective review for oncocytic neoplasms treated at our institution from 2012 to 2019. Formalin-fixed paraffin-embedded tissue blocks were used for tissue microarray construction. Tissue microarray blocks were cut into 5-μm sections and stained with anti-SSTR2 and anti-TSHR antibodies. Immunostains were analyzed by 3 independent pathologists. χ2 and logistic regression analysis were used to analyze clinical and pathologic variables. Sixty-seven specimens were analyzed with 15 OA and 52 OC. The mean age was 57 years, 61.2% were women, and 70% were White. SSTR2 positivity was noted in 2 OA (13%) and 15 OC (28%; 10 primary, 4 recurrent, and 1 metastatic) (P = .22). TSHR positivity was noted in 11 OA (73%) and 32 OC (62%; 31 primary and 1 metastatic) (P = .40). Those who presented with or developed clinical recurrence/metastasis were more likely to be SSTR2-positive (50% vs 21%; P = .04) and TSHR-negative (64.3% vs 28.9%; P = .02) than primary OC patients. Widely invasive OC was more likely to be SSTR2-positive compared to all other OC subtypes (minimally invasive and angioinvasive) (P = .003). For all patients with OC, TSHR positivity was inversely correlated with SSTR2 positivity (odds ratio, 0.12; CI, 0.03-0.43; P = .006). This relationship was not seen in the patients with OA (odds ratio, 0.30; CI, 0.01-9.14; P = .440). Our results show that recurrent/metastatic OC was more likely to be SSTR2-positive and TSHR-negative than primary OC. Patients with OC displayed a significant inverse relationship between SSTR2 and TSHR expression that was not seen in patients with OA. This may be a key relationship that can be used to prognosticate and treat OCs.

The histologic outcomes of indeterminate thyroid nodules with rat sarcoma mutations: A case series.

Molecular testing is an adjunct test for thyroid fine needle aspirations with indeterminate diagnoses, with certain mutations showing a greater risk of malignancy (ROM). Rat sarcoma (RAS) point mutations are the most common alterations in indeterminate thyroid nodules. While they can have a high ROM, they are also found in benign disease. This study describes the histologic outcomes of indeterminate nodules with RAS mutations. Bethesda III and IV thyroid nodules with ThyroSeq results showing RAS mutations (NRAS, KRAS, and HRAS) were identified between November 1, 2018 and February 28, 2023. Baseline patient characteristics, ThyroSeq results, and surgical diagnoses were collected. We identified 18 nodules with RAS mutations from 17 patients. Fourteen were NRAS (isolated NRAS in 6; NRAS with other abnormalities [NRAS+] in 8); one was isolated KRAS; and three were HRAS with other abnormalities (HRAS+). NRAS Q16R was the most common amino acid change. Twelve cases had follow-up. Two were malignant, a minimally invasive follicular carcinoma (NRAS+) and a papillary thyroid carcinoma, follicular variant (HRAS+). Three were noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP), 2 HRAS+ and 1 NRAS+. Four were follicular adenomas, one being atypical (3 NRAS+ and one isolated NRAS). One was an oncocytic adenoma (isolated NRAS). Two were nodular hyperplasias (isolated NRAS and NRAS+, respectively). Twenty-eight percent of our RAS-mutated nodules were malignant or NIFTP. All three HRAS-mutated nodules were malignant or NIFTP. The three isolated RAS mutations with follow up were benign (adenomas or nodular hyperplasia). These findings were in line with the literature.

Classification of Thyroid Tumors Based on DNA Methylation Patterns.

Background: Alterations in DNA methylation are stable epigenetic events that can serve as clinical biomarkers. The aim of this study was to analyze methylation patterns among various follicular cell-derived thyroid neoplasms to identify disease subtypes and help understand and classify thyroid tumors. Methods: We employed an unsupervised machine learning method for class discovery to search for distinct methylation patterns among various thyroid neoplasms. Our algorithm was not provided with any clinical or pathological information, relying exclusively on DNA methylation data to classify samples. We analyzed 810 thyroid samples (n = 256 for discovery and n = 554 for validation), including benign and malignant tumors, as well as normal thyroid tissue. Results: Our unsupervised algorithm identified that samples could be classified into three subtypes based solely on their methylation profile. These methylation subtypes were strongly associated with histological diagnosis (p < 0.001) and were therefore named normal-like, follicular-like, and papillary thyroid carcinoma (PTC)-like. Follicular adenomas, follicular carcinomas, oncocytic adenomas, and oncocytic carcinomas clustered together forming the follicular-like methylation subtype. Conversely, classic papillary thyroid carcinomas (cPTC) and tall cell PTC clustered together forming the PTC-like subtype. These methylation subtypes were also strongly associated with genomic drivers: 98.7% BRAFV600E-driven cancers were PTC like, whereas 96.0% RAS-driven cancers had a follicular-like methylation pattern. Interestingly, unlike other diagnoses, follicular variant PTC (FVPTC) samples were split into two methylation clusters (follicular like and PTC like), indicating a heterogeneous group likely to be formed by two distinct diseases. FVPTC samples with a follicular-like methylation pattern were enriched for RAS mutations (36.4% vs. 8.0%; p < 0.001), whereas FVPTC- with PTC-like methylation patterns were enriched for BRAFV600E mutations (52.0% vs. 0%, Fisher exact p = 0.004) and RET fusions (16.0% vs. 0%, Fisher exact p = 0.003). Conclusions: Our data provide novel insights into the epigenetic alterations of thyroid tumors. Since our classification method relies on a fully unsupervised machine learning approach for subtype discovery, our results offer a robust background to support the classification of thyroid neoplasms based on methylation patterns.

Probability of malignancy and molecular alterations as determined by ThyroSeq v3 genomic classifier in Bethesda Category IV.

ThyroSeq molecular testing assesses the probability of malignancy (POM) in thyroid fine-needle aspiration cytology (FNAC) with indeterminate cytology. The aim was to investigatewhether Bethesda category IV (BIV) subcategories are associated with specific molecular alterations, molecular-derived risk of malignancy (MDROM), and risk of malignancy (ROM). FNAC slides, associated ThyroSeq, version 3, Genomic Classifier results, and surgical follow-up were retrieved for BIV nodules. Nodules were subcategorized as follicular neoplasm (FN) with or without cytologic atypia or oncocytic follicular neoplasm (OFN). The MDROM, ROM, and frequency of molecular alterations in FN and OFN were analyzed. p < .05 was considered significant. A total of 92 FNAC were identified and subcategorized into 46 FN (15 with and 31 without cytologic atypia) and 46 OFN. The benign call rate and the positive call rate were 49% and 51%, respectively. The MDROM in BIV was 34.3%, trending lower in OFN than in FN. RAS mutations were significantly more frequent in FN when compared to OFN (p = .02). Chromosomal copy number alterationswere more often present in OFN than in FN (p < .01). On histologic follow-up, ROM in OFN was trending lower than in FN (p = .1). The most common diagnosis in OFN was oncocytic adenoma, whereas follicular variant papillary thyroid carcinoma was most common in FN. The MDROM and ROM were trending lower in OFN compared with FN, and the molecular alterations differed between OFN and FN subcategories.

Clinicopathologic features of thyroid nodules with PTEN mutations on preoperative testing.

The incidence of cancer in thyroid nodules carrying germline or somatic phosphatase and tensin homolog (PTEN) mutations is not well-defined. This study characterizes the clinical and histopathologic features of thyroid nodules with preoperatively detected PTEN mutations and their impact on management. Thyroid nodules with PTEN mutations on molecular testing of fine-needle aspiration (FNA) specimens from November 2017 to July 2020 at our institution were included. Demographic and clinicopathologic data were obtained through retrospective chart review. We identified 49 PTEN mutation-positive nodules from 48 patients. Surveillance was pursued for 28 patients and surgery for 20 patients. There were 14 follicular adenomas (FA), 4 oncocytic adenomas, 1 oncocytic hyperplastic nodule, and 1 encapsulated follicular variant papillary thyroid carcinoma (EFVPTC). The EFVPTC had two somatic PTEN mutations, an NRAS mutation, and was a low-risk tumor with capsular but no angiolymphatic invasion. Four patients, all with multiple nodules, had PTEN hamartoma syndrome (PHTS) with germline mutations or a clinical diagnosis of Cowden syndrome (CS); two had surgery finding FAs, and one previously had follicular carcinoma removed. Among surveillance patients, 1/20 had a significant increase in the size of the thyroid nodule and underwent repeat FNA, and no thyroid malignancy was found with a mean of 1.77 years of follow-up (range 1.00-2.78). Thyroid nodules with isolated somatic PTEN mutations are primarily benign and unlikely to grow at a high rate, at least on short-term follow-up. About 8% of patients with PTEN mutations may have PHTS or CS, which should be suspected in younger patients with multiple thyroid nodules.

Update regarding the role of PD-L1 in oncocytic thyroid lesions on cytological samples

AimsSeveral papers have shown that programmed death-ligand 1 (PD-L1) expression is a relevant predictive biomarker in anti-PD-L1 cancer immunotherapy. While its role in several human cancers is correlated with poor...

Subcutaneous implantation of oncocytic thyroid cell aggregates nine years later from thyroidectomy. A case report.

Introduction and importanceSubcutaneous implantation of thyroid tissue is a rare clinical condition that involves the head and neck region and occurs after surgery, diagnostic procedures or cervical trauma.Case presentationA 90-year old woman with two skin nodules on her thyroidectomy scar was hospitalized and treated by two surgical excisions. Histologically, these lesions were two aggregates of cutaneous oncocytic thyroid cells. In the patient's clinical history there was a total thyroidectomy for multinodular goiter, performed 9 years previously and at which a well-encapsulated subcapsular oncocytic adenoma of the left lobe was also incidentally discovered. At 12 months of follow-up, the patient is showed well and her wounds healed.Clinical discussionSubcutaneous colonization or seeding of thyroid tissue is a rare occurrence reported in the literature for both benign and malignant pathologies; among the malignant ones, the implantation of follicular carcinoma cells is the most frequent. Only in one previous case, to our knowledge, subcutaneous colonization originating from oncocytic thyroid (or Hurthle) cell neoplasms has been described.ConclusionWe report an unusual case of double subcutaneous implantation of oncocytic thyroid cells on the cervical scar of an elderly woman, nine years after total thyroidectomy.

Overview of the 2022 WHO Classification of Thyroid Neoplasms.

This review summarizes the changes in the 5th edition of the WHO Classification of Endocrine and Neuroendocrine Tumors that relate to the thyroid gland. The new classification has divided thyroid tumors into several new categories that allow for a clearer understanding of the cell of origin, pathologic features (cytopathology and histopathology), molecular classification, and biological behavior. Follicular cell-derived tumors constitute the majority of thyroid neoplasms. In this new classification, they are divided into benign, low-risk, and malignant neoplasms. Benign tumors include not only follicular adenoma but also variants of adenoma that are of diagnostic and clinical significance, including the ones with papillary architecture, which are often hyperfunctional and oncocytic adenomas. For the first time, there is a detailed account of the multifocal hyperplastic/neoplastic lesions that commonly occur in the clinical setting of multinodular goiter; the term thyroid follicular nodular disease (FND) achieved consensus as the best to describe this enigmatic entity. Low-risk follicular cell-derived neoplasms include non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), thyroid tumors of uncertain malignant potential, and hyalinizing trabecular tumor. Malignant follicular cell-derived neoplasms are stratified based on molecular profiles and aggressiveness. Papillary thyroid carcinomas (PTCs), with many morphological subtypes, represent the BRAF-like malignancies, whereas invasive encapsulated follicular variant PTC and follicular thyroid carcinoma represent the RAS-like malignancies. This new classification requires detailed subtyping of papillary microcarcinomas similar to their counterparts that exceed 1.0cm and recommends not designating them as a subtype of PTC. The criteria of the tall cell subtype of PTC have been revisited. Cribriform-morular thyroid carcinoma is no longer classified as a subtype of PTC. The term "Hürthle cell" is discouraged, since it is a misnomer. Oncocytic carcinoma is discussed as a distinct entity with the clear recognition that it refers to oncocytic follicular cell-derived neoplasms (composed of > 75% oncocytic cells) that lack characteristic nuclear features of PTC (those would be oncocytic PTCs) and high-grade features (necrosis and ≥ 5 mitoses per 2 mm2). High-grade follicular cell-derived malignancies now include both the traditional poorly differentiated carcinoma as well as high-grade differentiated thyroid carcinomas, since both are characterized by increased mitotic activity and tumor necrosis without anaplastic histology and clinically behave in a similar manner. Anaplastic thyroid carcinoma remains the most undifferentiated form; squamous cell carcinoma of the thyroid is now considered as a subtype of anaplastic carcinoma. Medullary thyroid carcinomas derived from thyroid C cells retain their distinct section, and there is a separate section for mixed tumors composed of both C cells and any follicular cell-derived malignancy. A grading system for medullary thyroid carcinomas is also introduced based on mitotic count, tumor necrosis, and Ki67 labeling index. A number of unusual neoplasms that occur in the thyroid have been placed into new sections based on their cytogenesis. Mucoepidermoid carcinoma and secretory carcinoma of the salivary gland type are now included in one section classified as "salivary gland-type carcinomas of the thyroid." Thymomas, thymic carcinomas and spindle epithelial tumor with thymus-like elements are classified as "thymic tumors within the thyroid." There remain several tumors whose cell lineage is unclear, and they are listed as such; these include sclerosing mucoepidermoid carcinoma with eosinophilia and cribriform-morular thyroid carcinoma. Another important addition is thyroblastoma, an unusual embryonal tumor associated with DICER1 mutations. As in all the WHO books in the 5th edition, mesenchymal and stromal tumors, hematolymphoid neoplasms, germ cell tumors, and metastatic malignancies are discussed separately. The current classification also emphasizes the value of biomarkers that may aid diagnosis and provide prognostic information.

Sarcomatoid Carcinoma Of The Mediastinal : A Rare Case of Giant Mass Thymic Carcinoma Subtype

ABSTRACTTitle: Sarcomatoid Carcinoma Of The Mediastinum: A Rare Case of Giant Mass Thymic Carcinoma SubtypeAuthor: Agus Andreas Santoso, MD. Pulmonology and Respiratory Medicine Department, Brawijaya University, Malang, Indonesia. Supervisor: Ngakan Putu Persama Putra, MD, Pulmonologist Consultant, Ungky Agus Setiawan, MD, Pulmonologist Consultant, Artono I, MD, Cardiovascular and Thorax Surgeon, Dini Rachma Erawati, MD, Radiologist Consultant, Hendy Setyo Yudhanto, MD, Pathology Anatomy Specialist.Introduction: Sarcomatoid carcinoma is a type of thymus carcinoma that contains partial or complete spindle cells. Incidence of Sarcomatoid Carcinoma 5-10% of all patients with thymic carcinoma. Carcinoma Sarcomatoid is a highly progressive tumor, most patients will die after 3 years of diagnosis despite aggressive multimodality therapy.Case Description: A 47-year-old woman with chest pain, shortness of breath, coughing, weight loss, enlarging lump in the neck and chest was felt for 1 month. Physical and supporting examination showed anterior superior mediastinal tumors and soft mass tissue in the right region of the Colli. Based on the Transthoracal FNAB Guiding ultrasound and FNAB the anterior colli region concluded that Thymoma, thyroid oncocytic adenoma and Nodular colloid goiter with azkanasy cell proliferation. The patient had Partial Sternotomy (Hemiclamshell), thymectomy with the final diagnosis of Sarcomatoid Carcinoma. Discussion: Sarcomatoid carcinoma is a type of thymic carcinoma that has both malignant epithelium (carcinomatous) and spindle cells (sarcomatous/sarcomatoid), generally with a transition between the two. This case was interesting because of the rare occurrence of Sarcomatoid Carcinoma plus the large size of tumor mass in this patient.Â

An ectopic adrenocortical oncocytic adenoma in the liver highly mimicking hepatocellular carcinoma: case report and literature review

BackgroundEctopic adrenocortical tissue is a lesion usually found incidentally during autopsy or inguinal surgery. Here, we demonstrate an extremely unusual case of intrahepatic adrenocortical adenoma which highly mimicks hepatocellular carcinoma (HCC) and brings challenges for clinicians and pathologists. The diagnostic pitfalls have been discussed in detail to provide clues for guiding differential diagnosis and future treatment.Case presentationA 44-year-old man was admitted into our hospital for evaluation of a hepatic mass identified during routine examination. Enhanced CT revealed its margin displayed apparent enhancement in arterial phase, but hypointensity in portal and delayed phase. HCC was suspected and partial hepatectomy was performed. Microscopically, cells were arranged in solid sheets. Most of the tumor cells were large, polygonal, had prominent nucleoli and were rich in eosinophilic cytoplasm. Pleomorphic nucleus was frequently found. Focally, smaller cells were found with small nuclei and granular cytoplasm. Immunohistochemically, tumor cells were negative for Arg-1, glypican-3 (GPC3), hepatocyte specific antigen (HSA), and positive for synaptophysin (Syn), α-inhibin, and Melan A. The Ki-67 index was 1 %. The final diagnosis was ectopic adrenocortical oncocytic adenoma and the patient was uneventful after the surgery.Conclusion Intrahepatic adrenocortical adenoma in the liver can hardly be diagnosed through radiology and little experience in pathology has been reported. In the present case, massive oncocytic changes and huge pleomorphism add greatly to the difficulties of making correct diagnosis. This lesion should be carefully kept in mind and a combination of markers is suggested for differentiating from HCC.

Impact of molecular testing on detecting mimics of oncocytic neoplasms in thyroid fine-needle aspirates diagnosed as follicular neoplasm of Hürthle cell (oncocytic) type.

Some thyroid nodules cytologically presenting as follicular neoplasm, Hürthle cell (Oncocytic) type (FNHCT), are not oncocytic tumors and represent autonomously functioning thyroid nodules (AFTNs) with TSHR, GNAS, and EZH1 mutations or oncocytic metaplasia. A to be defined subset of FNHCT harbors genome haploidisation-type DNA copy number alterations (GH-CNA). Molecular profiling of FNHCT may distinguish oncocytic neoplasms from its mimics. Consecutive fine-needle aspirates of 180 thyroid nodules over 37 months diagnosed as FNHCT and tested by ThyroSeq v3 were identified. Histologic follow-up was available for 79 of 180 nodules (44%). No molecular alterations were found in 76 of 180 nodules (42%), of which 15 were resected (oncocytic metaplasia, n = 7; follicular oncocytic adenoma, n = 8). Of nodules followed without surgery, 17 of 101 (17%) showed TSHR, EZH1, and GNAS mutations of AFTNs. Papillary thyroid carcinoma was identified by BRAF V600E (n = 2) and hyalinizing trabecular adenoma by PAX8-GLIS3 (n = 1). GH-CNA alone was detected in 42 of 180 FNHCT nodules (23%), of which 29 were resected and histologically diagnosed as follicular oncocytic neoplasms. All remaining resected nodules were histologically proven oncocytic neoplasms: 1) RAS-like alterations without GH-CNA (n = 25) and 2) TERT and/or TP53 mutations co-occurring with GH-CNA (n = 6), including anaplastic thyroid carcinoma arising from follicular oncocytic carcinoma with TP53, TERT mutations with GH-CNA (n = 2). A proportion of FNHCT nodules are AFTNs and oncocytic metaplasias, which can be suspected based on characteristic mutations or lack of alterations on molecular testing. Among resected FNHCTs, GH-CNAs characterize approximately half of histologically confirmed follicular oncocytic neoplasms.

Characteristics of different histological subtypes of thyroid nodules classified with 99mTc-methoxy-isobutyl-isonitrile imaging and Thyroid Imaging Reporting And Data System

Thyroid Imaging Reporting And Data System (TIRADS) is helpful for risk stratification of thyroid nodules. However, there is a lack of data for TIRADS classification of different histological subtypes [classical papillary thyroid cancer (PTC), follicular variant of papillary thyroid cancer (FVPTC), and follicular thyroid cancer (FTC)], and benign thyroid nodules (follicular adenoma, oncocytic adenoma, and multinodular goiter (MNG)]. Methoxy-isobutyl-isonitrile (MIBI) imaging has a high negative predictive value for the exclusion of thyroid malignancy in hypofunctioning thyroid nodules. The aim of this analysis was to compare malignant and benign subtypes of thyroid nodule using three TIRADS and MIBI imaging. Retrospective analysis of MIBI imaging studies. Hypofunctioning thyroid nodules were classified with Kwak-TIRADS, EU-TIRADS, and K-TIRADS. MIBI imaging was visually categorized. We included 242 thyroid nodules (32 malignant, 19 PTC, 7 FVPTC, and 6 FTC). When using Kwak-TIRADS 4C and 5 as a marker for high-risk nodules, we found 85.5% of the follicular adenoma, 80.8% of the MNG, 100% of the oncocytic adenoma, 100% of the FTC, 57.1% of the FVPTC, and 42.2% of the PTC to be below this cutoff. All PTC and FVPTC were MIBI-positive, 83% of the FTC, 78% of the follicular adenoma, 75% of the oncocytic adenoma, and 60% of the MNG were MIBI-positive. TIRADS is useful to detect PTC, but FVPTC and FTC may be missed. MIBI imaging seems to be more suitable to detect FVPTC and FTC. However, neither TIRADS nor MIBI imaging are able to differentiate between follicular adenoma and FTC or FVPTC.