Follicular neoplasm of the thyroid--vanishing cytologic diagnosis?

Multi-Omics and Management of Follicular Carcinoma of the Thyroid

Follicular thyroid carcinoma (FTC) is the second most common cancer of the thyroid gland, accounting for up to 20% of all primary malignant tumors in iodine-replete areas. The diagnostic work-up, staging, risk stratification, management, and follow-up strategies in patients who have FTC are modeled after those of papillary thyroid carcinoma (PTC), even though FTC is more aggressive. FTC has a greater propensity for haematogenous metastasis than PTC. Furthermore, FTC is a phenotypically and genotypically heterogeneous disease. The diagnosis and identification of markers of an aggressive FTC depend on the expertise and thoroughness of pathologists during histopathological analysis. An untreated or metastatic FTC is likely to de-differentiate and become poorly differentiated or undifferentiated and resistant to standard treatment. While thyroid lobectomy is adequate for the treatment of selected patients who have low-risk FTC, it is not advisable for patients whose tumor is larger than 4 cm in diameter or has extensive extra-thyroidal extension. Lobectomy is also not adequate for tumors that have aggressive mutations. Although the prognosis for over 80% of PTC and FTC is good, nearly 20% of the tumors behave aggressively. The introduction of radiomics, pathomics, genomics, transcriptomics, metabolomics, and liquid biopsy have led to improvements in the understanding of tumorigenesis, progression, treatment response, and prognostication of thyroid cancer. The article reviews the challenges that are encountered during the diagnostic work-up, staging, risk stratification, management, and follow-up of patients who have FTC. How the application of multi-omics can strengthen decision-making during the management of follicular carcinoma is also discussed.

Polymorphous adenocarcinoma of the salivary glands: reappraisal and update

Although relatively rare, polymorphous adenocarcinoma (PAC) is likely the second most common malignancy of the minor salivary glands (MiSG). The diagnosis is mainly based on an incisional biopsy. The optimal treatment comprises wide surgical excision, often with adjuvant radiotherapy. In general, PAC has a good prognosis. Previously, PAC was referred to as polymorphous low-grade adenocarcinoma (PLGA), but the new WHO classification of salivary gland tumours has also included under the PAC subheading, the so-called cribriform adenocarcinoma of minor salivary glands (CAMSG). This approach raised controversy, predominantly because of possible differences in clinical behaviour. For example, PLGA (PAC, classical variant) only rarely metastasizes, whereas CAMSG  often shows metastases to the neck lymph nodes. Given the controversy, this review reappraises the definition, epidemiology, clinical presentation, diagnostic work-up, genetics, treatment modalities, and prognosis of PAC of the salivary glands with a particular focus on contrasting differences with CAMSG.

Encapsulated Follicular Variant of Thyroid Papillary Carcinoma - Case Report and Differential Diagnosis Discussion

Papillary carcinoma is the most common type of epithelial thyroid cancer in women, especially in the reproductive period, accounting for about 75-80% of well-differentiated cancers at this level. One of its variants, follicular encapsulated thyroid carcinoma, is a well-differentiated malignant tumor with good prognosis which, despite the presence of vascular and capsular invasion, rarely causes metastasis, if fully resected. We present the case of a young patient who presented with dysphagia and a painless cystic nodular lesion of the thyroid, and underwent thyroidectomy. The histopathological diagnosis of the lesion was a challenge, being based on the correlation of clear criteria, given the existence of numerous lesions with follicular pattern in the thyroid.

Probing eukaryotic cell mechanics via mesoscopic simulations

Cell mechanics has proven to be important in many biological processes. Although there is a number of experimental techniques which allow us to study mechanical properties of cell, there is still a lack of understanding of the role each sub-cellular component plays during cell deformations. We present a new mesoscopic particle-based eukaryotic cell model which explicitly describes cell membrane, nucleus and cytoskeleton. We employ Dissipative Particle Dynamics (DPD) method that provides us with the unified framework for modeling of a cell and its interactions in the flow. Data from micropipette aspiration experiments were used to define model parameters. The model was validated using data from microfluidic experiments. The validated model was then applied to study the impact of the sub-cellular components on the cell viscoelastic response in micropipette aspiration and microfluidic experiments.

The Diagnostic Usefulness of HMGA2, Survivin, CEACAM6, and SFN/14-3-3 δ in Follicular Thyroid Carcinoma

Background:

Follicular thyroid carcinoma (FTC) is the second most common thyroid malignancy and its differential diagnosis includes follicular adenoma (FA) and adenomatous goiter (AG). Several ancillary markers have been suggested to aid in the diagnosis of FTC, but the successful use of these methods still needs to be validated.

Methods:

In the present study, we verified the immunoexpression of HMGA2, CEACAM6, survivin, and SFN/14-3-3 δ in lesions including 41 AGs, 72 FAs, and 79 FTCs. We evaluated their diagnostic usefulness, combined with galectin 3, Hector Battifora mesothelial 1 (HBME1), cytokeratin 19, and cyclin D1, in diagnosing FTC.

Results:

The expressions of HBME1 (65.8%) and HMGA2 (55.7%) were significantly higher in FTCs than in FAs and AGs (p<.001 and p=.005, respectively). HBME1 was the only marker that was more frequently expressed in FTCs than in FAs (p=.021) and it was more frequently expressed in follicular neoplasms than in AGs (p<.001). Among the novel markers, the combination of HMGA2 and HBME1 showed the highest sensitivity (72.2%) and specificity (76.1%) for diagnosing FTC. CEACAM6, survivin, and SFN/14-3-3 δ were barely expressed in most cases.

Conclusions:

Our present results show that only HMGA2 can be beneficial in differentiating FTC using the novel markers.

The role of core needle biopsy in the preoperative diagnosis of follicular neoplasm of the thyroid

Follicular neoplasm/suspicious for follicular neoplasm (FN/SFN) can often be challenging to diagnose using core needle biopsy (CNB) specimens. We have developed the histologic criteria for the CNB diagnosis of FN and validated the usefulness of CNB. We retrospectively reviewed 184 CNBs and 224 FNACs diagnosed with FN/SFN. CNBs were histologically classified into four subgroups, based on the histologic features of follicular proliferation, fibrous capsulation, and surrounding parenchyma. Among 184 CNBs, 103 (55.9%) had previous FNAC results of non-diagnostic or indeterminate. Overall malignancy rates in FNAC (48%) and CNB (46%) were nearly identical (p > 0.05), and the neoplasm rate was higher in CNB (88%) than FNAC (74%) (p = 0.007). There was no significant difference in the malignancy rates among the four histologic subgroups. Among the 40 nodules with simultaneous CNB and FNAC, only nine had the FNAC diagnosis of FN/SFN, and others were non-diagnostic, benign, or atypia of undetermined significance. Overall, CNB improved specimen adequacy and achieved better sensitivity of the FN/SFN diagnosis in thyroid nodules that were inconclusive by FNAC. In the preoperative diagnosis of FN/SFN, CNB has no advantage over FNAC in predicting the likelihood of malignancy, but helps to reduce the need for repeat biopsy.

Fine needle aspiration cytology of thyroid follicular neoplasm: cytohistologic correlation and accuracy

BACKGROUND

This study evaluated the accuracy of fine needle aspiration cytology (FNAC) in cases of follicular neoplasm (FN) on the basis of histologic diagnosis, and reviewed the cytologic findings of FN according to the FNAC.

METHODS

Among the 66 cases diagnosed with thyroid FN by FNAC during the 7-year period from 2003 to 2009, 36 cases that had undergone thyroid surgery were available for review. Cytologic diagnosis was compared with the histologic diagnosis of each case.

RESULTS

Among the 36 cases with a cytologic diagnosis of thyroid FN, histologic diagnosis was as follows: 20 follicular adenomas (55.6%), 3 Hurthle cell adenomas (8.3%), 2 follicular carcinomas (5.6%), 8 nodular goiters (22.2%), 2 papillary carcinomas (5.6%), and 1 Hashimoto's thyroiditis (2.8%), resulting in a diagnostic accuracy of FNAC for thyroid FN of 69.5%.

CONCLUSIONS

This study shows that FNAC for thyroid FN is a useful primary screening method because when FN is diagnosed by FNAC, the rate of FN histologic diagnosis is relatively high, however, adequate sampling and experience is a prerequisite for this procedure.

Changes in expression of human serine protease HtrA1, HtrA2 and HtrA3 genes in benign and malignant thyroid tumors

Human HtrA proteins are serine proteases involved in essential physiological processes. HtrA1 and HtrA3 function as tumor suppressors and inhibitors of the TGF-β signaling pathway. HtrA2 regulates mitochondrial homeostasis and plays a pivotal role in the induction of apoptosis. The aim of the study was to determine whether the HtrA proteins are involved in thyroid carcinogenesis. We used the immunoblotting technique to estimate protein levels of HtrA1, HtrA2, long and short variants of HtrA3 (HtrA3-L and HtrA3-S) and TGF-β1 in tissues of benign and malignant thyroid lesions, and control groups. We found that the levels of HtrA2 and HtrA3-S were higher in thyroid malignant tumors compared to normal tissues and benign tumors. The HtrA3-L level was increased in malignant tumor tissues compared to benign tumor tissues and control tissues from patients with benign lesions, and elevated in normal tissues from patients with thyroid carcinoma compared to normal tissues from patients with benign lesions. We also compared levels of HtrA proteins in follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC) and found that these types of carcinoma differed in the expression of HtrA3-S and HtrA1. These results indicate the implication of HtrA proteins in thyroid carcinogenesis suggest that HtrA3 variants may play different roles in cancer development, and that the increased HtrA3-L levels in thyroid tissue could be correlated with the development of malignant lesions. The TGF-β1 levels in tumor tissues were not significantly altered compared to control tissues.

Divide and rule: cytodiagnosis of thyroid lesions using pattern analysis: a study of 233 cases

Fine needle aspiration cytology (FNAC) of the thyroid is a simple, accurate, fast, economical and safe method for the diagnosis of thyroid lesions on FNA. The objective of this study was application of pattern analysis in the interpretation of thyroid lesions. Two hundred and thirty three cases of thyroid lesion were reviewed, which had histopathological correlation. Smears were classified based on primary (predominant) and secondary (next dominant) pattern and categorized. The variation between combined and final cytological diagnosis was correlated with the histopathological diagnosis. The sensitivity, specificity and diagnostic accuracy for the diagnosis of malignancy were 90.47, 100 and 99.14%. Our study demonstrates the feasibility and applicability of pattern analysis in diagnosing thyroid lesions, which could be easily reproducible.

Application of pattern analysis in fine needle aspiration of solitary nodule of thyroid

BACKGROUND

Various methods are used to arrive at a conclusive diagnosis of thyroid lesions on fine needle aspiration cytology (FNAC). Systemic pattern analysis is one such that can be used to analyze the lesions and divide them into individual categories.

AIMS

To study the application of pattern analysis in the interpretation of solitary thyroid nodule (STN).

MATERIALS AND METHODS

Two hundred and nineteen cases of fine needle aspiration cytology of STN were reviewed along with histopathological correlation. Smears were classified based on primary and secondary patterns. Predominant pattern (primary) was identified and lesion categorized. This was followed by identifying the next dominant pattern (secondary) and recategorization. Cytological diagnosis based on primary and secondary patterns was correlated with the histopathological diagnosis.

RESULTS

Based on pattern analysis, the study had a sensitivity of 66.7% and specificity of 98.9%. The positive predictive value and negative predictive value were 88.9% and 96% respectively and the overall diagnostic accuracy was 95.4%.

CONCLUSIONS

The present study demonstrates the feasibility and applicability of pattern analysis in diagnosing thyroid lesions by FNAC, which could be easily reproducible.

Evaluation of a new method for the diagnosis of alterations of Lens culinaris agglutinin binding of thyroglobulin molecules in thyroid carcinoma

BACKGROUND

The measurement of serum thyroglobulin (Tg) is widely used as a marker for recurrence of thyroid carcinoma following total thyroidectomy. However, this method cannot differentiate between benign and malignant disease. We focused on the sugar chain in the Tg molecule and investigated the usefulness of Lens culinaris agglutinin (LCA)-reactive Tg ratios in sera and wash fluids obtained during fine-needle aspiration (FNA) for the detection of thyroid carcinoma.

METHODS

The study was performed using 203 serum samples (115 from patients with benign thyroid disease and 88 from patients with thyroid carcinomas) and 176 wash fluid samples (143 benign, 21 malignant, and 12 inconclusive). LCA-reactive Tg ratios were determined using an enzyme-linked immunosorbent assay, and a comparison was made between malignant and benign lesions.

RESULTS

In serum, the ratio in patients with malignancy was 79.5+/-6.0 [mean+/-standard deviation (SD)], significantly lower than in patients with benign lesions (84.9+/-3.5). The ratios in wash fluid from malignant lesions (75.8+/-18.9) were also significantly lower than those from benign lesions (85.6+/-3.9).

CONCLUSIONS

These results suggest that this method could distinguish between benign and malignant lesions and may be useful for screening serum and wash samples.

NA cohort study of thyroid cancer and other thyroid diseases after the Chernobyl accident: cytohistopathologic correlation and accuracy of fine-needle aspiration biopsy in nodules detected during the first screening in Ukraine (1998-2000)

BACKGROUND

The Ukrainian American Cohort Study was established to evaluate the risk of thyroid disorders in a group exposed as children and adolescents to 131I by the Chernobyl accident (arithmetic mean thyroid dose, 0.79 grays). Individuals are screened by palpation and ultrasound and are referred to surgery according to fine-needle aspiration biopsy (FNA). However, the accuracy of FNA cytology for detecting histopathologically confirmed malignancy after this level of internal exposure to radioiodines is unknown.

METHODS

During the first screening cycle (1998-2000), 13,243 individuals were examined, 356 individuals with thyroid nodules were referred for FNA, 288 individuals completed the procedure, 85 individuals were referred to surgery, 82 individuals underwent surgery, and preoperative cytology was available for review in 78 individuals. Cytologic interpretation for the nodule that resulted in surgical referral was correlated with final pathomorphology; discrepancies were reviewed retrospectively; and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FNA cytology were calculated.

RESULTS

All 24 cytologic interpretations that were definite for papillary thyroid cancer (PTC) were confirmed histopathologically (PPV, 100%); and, of 11 cytologic interpretations that were suspicious for PTC, 10 were confirmed (PPV, 90.9%). Ten of 41 FNAs that were interpreted as either definite or suspect for follicular neoplasm were confirmed as malignant (PPV, 24.4%), including 2 follicular thyroid cancers and 8 PTCs (all but 1 of the follicular or mixed subtypes). Depending on whether a cytologic interpretation of follicular neoplasm was considered "positive" or "negative," the sensitivity was 100% and 77.3%, respectively; similarly, the respective specificity was 17.6% and 97.1%, the respective PPV was 61.1% and 97.1%, and the respective NPV was 100% and 76.7%.

CONCLUSIONS

Among children and adolescents who were exposed to 131I after the Chernobyl accident and were evaluated 12 to 14 years later, thyroid cytology had a sensitivity and a predictive value similar to those reported in unexposed populations.

Hemosiderin laden macrophages and hemosiderin within follicular cells distinguish benign follicular lesions from follicular neoplasms

Background:

Published criteria to distinguish benign colloid nodules from follicular neoplasms emphasize only three interdependent features: size of follicles, amount of colloid, and cellularity. There is a need for the validation of other independent criteria.

Methods:

This study quantified the significance of cystic change, defined as presence of macrophages, and the presence of hemosiderin in either the macrophages or follicular cells. The cohort consisted of 165 patients with fine needle aspiration (FNA) and histologic follow-up of either goiter (101), follicular adenoma (47), or follicular carcinoma (17). Papillary thyroid carcinomas and Hürthle cell neoplasms were excluded from the cohort, because these categories are known to show cystic change and hemosiderin. FNAs were reviewed blindly with the most cellular slide scored for the presence of macrophages and/or hemosiderin.

Results:

Hemosiderin within macrophages were seen in 67% (68 of 101) of the goiters and only 6% (four of 64) of follicular neoplasms (P<.0001). All four follicular neoplasms with hemosiderin in macrophages were adenomas. Three of these four had equivocal features of a benign colloid nodule histologically. None of the 17 follicular carcinomas had hemosiderin in macrophages (P<.12). Macrophages without hemosiderin also strongly distinguished goiters from neoplasms (83% vs 17%) but appears less useful as a criterion since macrophages were present within 3 of 17 follicular carcinomas. Hemosiderin within follicular epithelial cells was present in 18% (18 of 101) of goiters, whereas none of the 64 follicular neoplasms had intraepithelial hemosiderin (P<.0003).

Conclusions:

If papillary thyroid carcinoma and Hürthle cell neoplasm are ruled out, our findings indicate that the presence of hemosiderin virtually excludes a clinically significant follicular neoplasm.

A cohort study of thyroid cancer and other thyroid diseases after the Chornobyl accident: pathology analysis of thyroid cancer cases in Ukraine detected during the first screening (1998-2000)

BACKGROUND

The Ukrainian American Cohort Study evaluated the risk of thyroid disorders in a group of individuals who were younger than age 18 years at the time of the Chornobyl (Chernobyl) accident. In this article, the authors describe the pathology of thyroid carcinomas detected in the first screening.

METHODS

From 1998 to 2000, 13,243 individuals completed the first cycle of screening examinations. Eighty patients underwent surgery between 1998 and 2004. Intraoperative and postoperative pathologic studies were performed at the Institute of Endocrinology and Metabolism, Kyiv.

RESULTS

Pathologic analysis revealed 45 thyroid carcinomas, including 43 papillary thyroid carcinomas (PTCs) (95.6%) and 2 follicular thyroid carcinomas (FTCs) (4.4%). TNM classification (5th edition) of the PTCs included 8 T1 tumors (18.6%), 16 T2 tumors (37.2%), and 19 T4 tumors (44.2%). Fifteen PTCs (34.9%) were N1a,N1b, and 3 PTCs (7.0%) were M1. Among the PTCs, 8 exhibited the classical papillary histologic pattern (18.6%), 14 exhibited a follicular histologic pattern (32.6%), 5 exhibited a solid histologic pattern (11.6%), and 16 exhibited a mixed histologic pattern (37.2%). Both FTCs had a microfollicular-solid structure. Eleven of 20 cohort members who underwent surgery before the first screening had PTCs. Regional metastases (63.6%) and distant metastases (18.2%) were more common in this group.

CONCLUSIONS

Multifocal growth, lymphatic and blood vessel invasion, extrathyroid spread, and regional and distant metastases were more frequent in less differentiated PTCs (>30% solid structure). Small carcinomas (</=10 mm) comprised 23.3% of PTCs, and most of those (8 of 10 small carcinomas; 80%) were of the papillary-follicular subtype and therefore were more differentiated. The solid subtype of PTC was associated with shorter latency, especially in individuals who were diagnosed before the first screening. The histology of post-Chornobyl cancers is changing with time.