Endocrine Pathology最新文献

PitNETs are usually restricted in their cytodifferentiation to only one of 3 lineages dictated by expression of the pituitary transcription factors (TFs) PIT1, TPIT, or SF1. Tumors that show lineage infidelity and express multiple TFs are rare. We searched the pathology files of 4 institutions for PitNETs with coexpression of PIT1 and SF1. We identified 38 tumors in 21 women and 17 men, average age 53 (range 21-79) years. They represented 1.3 to 2.5% of PitNETs at each center. Acromegaly was the presentation in 26 patients; 2 had central hyperthyroidism associated with growth hormone (GH) excess and one had significantly elevated prolactin (PRL). The remainder had mass lesions with visual deficits, hypopituitarism, and/or headaches. Tumor size ranged from 0.9 to 5 cm; all 7 lesions smaller than 1 cm were associated with acromegaly. Larger lesions frequently invaded the cavernous sinuses. Four cases represented a second attempt at surgical resection. PIT1 was usually diffusely positive but 5 cases had variable (patchy or focal) staining. SF1 reactivity was variable in intensity but diffuse in all but 2 cases. GATA3 data, available in 14 cases, identified diffuse positivity in 5 and focal staining in 1. GH was expressed in all but 5 tumors, PRL and thyrotropin (TSH) were expressed in 14 and 13, respectively, follicle-stimulating hormone (FSH) in 11 of 18, and luteinizing hormone (LH) in 4 of 17. Keratin staining patterns were diffuse perinuclear/membranous in 27, variable perinuclear in 4, and negative in 3; scattered fibrous bodies were seen in 5 and diffuse fibrous bodies in 1. Ki67 labeling index ranged from < 1 to 7.9%. In 3 cases, these tumors represented one of multiple synchronous PitNETs; a separate corticotroph tumor was seen in 2 patients and one patient had 2 additional discrete lesions, a sparsely granulated lactotroph, and a pure gonadotroph tumor comprising a triple tumor. PitNETs expressing PIT1 and SF1 represent multilineage PitNETs. These rare tumors have variable clinical and morphological features, most often presenting as large tumors with GH excess and occasionally as one of multiple synchronous PitNETs of distinct lineages.

Reliable preoperative diagnosis of thyroid nodules remained challenging because of the inconclusiveness of fine-needle aspiration (FNA) cytology. In the present study, 583 formalin-fixed paraffin embedded (FFPE) thyroid nodule tissues and 161 FNA specimens were enrolled retrospectively. Then BRAF V600E, EZH1 Q571R, SPOP P94R, and ZNF148 mutations among these samples were identified using Sanger sequencing. Based on this four-gene genomic classifier, we proposed a two-step modality to diagnose thyroid nodules to differentiate benign and malignant thyroid nodules. In the FFPE group, thyroid cancers were effectively diagnosed in 37.7% (220/583) of neoplasms by the primary BRAF V600E testing, and 15.7% (57/363) of thyroid nodules could be further determined as benign by subsequent EZH1 Q571R, SPOP P94R, and ZNF148 (we called them "ESZ") mutation testing. In the FNA group, 161 BRAF wild-type specimens were classified according to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). A total of 7 mutated samples fell within Bethesda categories III-IV, and the mutation rate of "ESZ" in Bethesda III-IV categories was 8.4%. The two-step genomic classifier could further improve thyroid nodule diagnosis, which may inform more optimal patient management.

Differentiated high-grade thyroid carcinoma (DHGTC) is a new entity in the 2022 WHO classification. We aimed to investigate the incidence and clinicopathological features of differentiated HG thyroid carcinoma (DHGTC) and compare the clinicopathological parameters of DHGTC, DTC without HG features, and poorly differentiated thyroid carcinoma (PDTC). A total of 1069 DTCs including papillary thyroid carcinomas (PTCs) and follicular thyroid carcinomas (FTCs) were included in this study. Consecutive 22 PDTCs were also included for comparative purposes. There were a total of 14 (1.3%) cases of DHGTCs, with 13 HGPTCs (1.2% of PTCs) and one HGFTC (6.7% of FTCs). Compared to DTCs without HG features, DHGTCs were associated with larger tumor size, presence of blood vessel invasion, gross extrathyroidal extension, distant metastasis at the time of diagnosis, higher American Joint Committee on Cancer stage, high American Thyroid Association risk, and TERT promoter mutations. DHGTC and PDTC showed a significantly shorter recurrence-free survival (RFS) than DTC without HG features. Multivariate Cox regression analysis revealed that blood vessel invasion, lateral node metastasis, TERT promoter mutations, and HG features were independent prognostic factors (all p < 0.05). When tumor necrosis and increased mitotic count were evaluated separately, tumor necrosis, but not increased mitotic counts, was found to be an independent prognostic factor (p = 0.006). This study confirmed that DHGTC is significantly associated with aggressive clinicopathological features and poor clinical outcomes, similar to PDTC. Although the incidence is low, careful microscopic examination of HG features in DTC is required.

A 44-year-old female patient with a familial adenomatous polyposis (FAP) was diagnosed with a cribriform morular thyroid carcinoma (CMTC). We observed within the very necrotic tumor a small but distinct poorly differentiated carcinomatous component. As expected, next generation sequencing of both components revealed a homozygous APC mutation and in addition, a TERT promoter mutation. A TP53 mutation was found exclusively in the CMTC part, while the poorly differentiated component showed a clonal evolution, harboring an activating PIK3CA mutation and copy number gains of BRCA2, FGF23, FGFR1, and PIK3CB-alterations which are typically seen in squamous cell carcinoma. The mutational burden in both components was low, and there was no evidence for microsatellite instability. No mutations involving the mitogen-activated protein kinase (MAPK) pathway, typically seen in papillary thyroid carcinomas, were detected. Immunohistochemically, all tumor parts were negative for thyroglobulin, providing further evidence that this entity does not belong to the follicular epithelial cell-derived thyroid carcinoma group. CD5 was negative in the poorly differentiated component, making a relation to intrathyroidal thymic carcinoma rather unlikely. However, since this marker was seen in the morules, a loss in the poorly differentiated component and a relation to the ultimobranchial body cannot be excluded either. After total thyroidectomy and radioiodine ablation, the patient was disease-free with no residual tumor burden on 2-year follow-up.

Bilateral macronodular adrenocortical disease (BMAD) is characterized by the development of adrenal macronodules resulting in a pituitary-ACTH independent Cushing's syndrome. Although there are important similarities observed between the rare microscopic descriptions of this disease, the small series published are not representative of the molecular and genetic heterogenicity recently described in BMAD. We analyzed the pathological features in a series of BMAD and determined if there is correlation between these criteria and the characteristics of the patients. Two pathologists reviewed the slides of 35 patients who underwent surgery for suspicion of BMAD in our center between 1998 and 2021. An unsupervised multiple factor analysis based on microscopic characteristics divided the cases into 4 subtypes according to the architecture of the macronodules (containing or not round fibrous septa) and the proportion of the different cell types: clear, eosinophilic compact, and oncocytic cells. The correlation study with genetic revealed subtype 1 and subtype 2 are associated with the presence of ARMC5 and KDM1A pathogenic variants, respectively. By immunohistochemistry, all cell types expressed CYP11B1 and HSD3B1. HSD3B2 staining was predominantly expressed by clear cells whereas CYP17A1 staining was predominant on compact eosinophilic cells. This partial expression of steroidogenic enzymes may explain the low efficiency of cortisol production in BMAD. In subtype 1, trabeculae of eosinophilic cylindrical cells expressed DAB2 but not CYP11B2. In subtype 2, KDM1A expression was weaker in nodule cells than in normal adrenal cells; alpha inhibin expression was strong in compact cells. This first microscopic description of a series of 35 BMAD reveals the existence of 4 histopathological subtypes, 2 of which are strongly correlated with the presence of known germline genetic alterations. This classification emphasizes that BMAD has heterogeneous pathological characteristics that correlate with some genetic alterations identified in patients.

Follicular-patterned lesions often have indeterminate results (diagnostic category III or IV) by core needle biopsy (CNB) and fine needle aspiration (FNA). However, CNB diagnoses follicular neoplasm (category IV) more frequently than FNA. Therefore, we aimed to develop a risk stratification system for CNB samples with category III/IV using immunohistochemistry (IHC). The specificity of the RAS Q61R antibody was validated on 58 thyroid nodules with six different types of RAS genetic variants and 40 cases of RAS wild-type. We then applied IHC analysis of RAS Q61R to 207 CNB samples with category III/IV in which all patients underwent surgical resection. RAS Q61R IHC had 98% sensitivity and 98% specificity for detecting the RAS p.Q16R variant. In an independent dataset, the positive rate of RAS Q61R was significantly higher in NIFTP (48%) and malignancies (45%) than in benign tumors (19%). The risk of NIFTP/malignancy was highest in the group with nuclear atypia and RAS Q61R expression (86%) and lowest in the group without both parameters (32%). The high-risk group with either nuclear atypia or RAS Q61R had 67.3% sensitivity, 73.4% specificity, 75.2% positive predictive value, and 65.1% negative predictive value for identifying NIFTP/malignancy. We conclude that RAS Q61R IHC can be a rule-in diagnostic test for NIFTP/malignancy in CNB category III/IV results. Combining of the histologic parameter (nuclear atypia) with RAS Q61R IHC results can further stratify CNB category III/IV into a high-risk group, which is sufficient for a surgical referral, and a low-risk group sufficient for observation.