Profile of BRAFV600E, BRAFK601E, NRAS, HRAS, and KRAS Mutational Status, and Clinicopathological Characteristics of Papillary Thyroid Carcinoma in Indonesian National Referral Hospital

Nuclear pseudoinclusion is associated with BRAFV600E mutation: Analysis of nuclear features in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is the most prevalent thyroid neoplasm, classified into BRAF-like and RAS-like subtypes. Nuclear alterations serve as a diagnostic criterion of PTC and are fully manifested in BRAF-like. This single-center retrospective study aimed to assess the different presentation of nuclear features in 40 samples of BRAFV600E- and 40 samples of RAS-mutated PTCs using both bivariate and multivariate analytic approaches. Nuclear features are evaluated histologically using the 3-point and 8-point scoring systems established by the World Health Organization and the Asian Thyroid Working Group, respectively. We found the presence of membrane irregularities, nuclear elongation, nuclear groove, sickle-shaped nuclei, nuclear pseudoinclusion, and higher nuclear scores are significantly associated with BRAFV600E. Multivariate analysis showed that nuclear pseudoinclusion is predictive for the presence of BRAFV600E mutation (OR = 10.97, 95%CI = 2.81-42.96, p = 0.001) and has sensitivity of 55 %, specificity of 92.5 %, positive predictive value of 88 %, negative predictive value of 67.3 %, and accuracy of 73.8 %. There are various pathways and protooncogenes associated with the development of thyroid neoplasm. This study found significant differences in nuclear features between BRAFV600E and RAS-mutated PTC. BRAFV600E tend to display florid nuclear features, whereas the RAS- mutation is associated with subtle nuclear features. These findings emphasize the distinct cytological profiles of BL and RL PTC, reinforcing the need for precise subtyping to guide tailored management.

Diagnostic challenges in the assessment of thyroid neoplasms using nuclear features and vascular and capsular invasion: a multi-center interobserver agreement study

BACKGROUND

The diagnosis of thyroid neoplasms necessitates the identification of distinct histological features. Various education/hospital centers located in cities across Indonesia likely result in discordances among pathologists when diagnosing thyroid neoplasms.

METHODS

This study examined the concordance among Indonesian pathologists in assessing nuclear features and capsular and vascular invasion of thyroid tumors. Fifteen pathologists from different centers independently assessed the same 14 digital slides of thyroid tumor specimens. All the specimens were thyroid neoplasms with known BRAFV600E and RAS mutational status, from a single center. We evaluated the pre- and post-training agreement using the Fleiss kappa. The significance of the training was evaluated using a paired T-test.

RESULTS

Baseline agreement on nuclear features was slight to fair based on a 3-point scoring system (k = 0.14 to 0.28) and poor to fair based on an eight-point system (k = -0.02 to 0.24). Agreements on vascular (κ = 0.35) and capsular invasion (κ = 0.27) were fair, whereas the estimated molecular type showed substantial agreement (κ = 0.74). Following the training, agreement using the eight-point system significantly improved (p = 0.001).

CONCLUSIONS

The level of concordance among Indonesian pathologists in diagnosing thyroid neoplasm was relatively poor. Consensus in pathology assessment requires ongoing collaboration and education to refine diagnostic criteria.

Recombinant Human TSH Fails to Induce the Proliferation and Migration of Papillary Thyroid Carcinoma Cell Lines

Thyrotropin (TSH) suppression is required in the management of patients with papillary thyroid carcinoma (PTC) to improve their outcomes, inevitably causing iatrogenic thyrotoxicosis. Nevertheless, the evidence supporting this practice remains limited and weak, and in vitro studies examining the mitogenic effects of TSH in cancerous cells used supraphysiological doses of bovine TSH, which produced conflicting results. Our study explores, for the first time, the impact of human recombinant thyrotropin (rh-TSH) on human PTC cell lines (K1 and TPC-1) that were transformed to overexpress the thyrotropin receptor (TSHR). The cells were treated with escalating doses of rh-TSH under various conditions, such as the presence or absence of insulin. The expression levels of TSHR and thyroglobulin (Tg) were determined, and subsequently, the proliferation and migration of both transformed and non-transformed cells were assessed. Under the conditions employed, rh-TSH was not adequate to induce either the proliferation or the migration rate of the cells, while Tg expression was increased. Our experiments indicate that clinically relevant concentrations of rh-TSH cannot induce proliferation and migration in PTC cell lines, even after the overexpression of TSHR. Further research is warranted to dissect the underlying molecular mechanisms, and these results could translate into better management of treatment for PTC patients.

Lymph Node Metastasis in Papillary Thyroid Carcinoma, A Study of BRAF V600E and TERT Promoter Mutations

OBJECTIVE

This study was designed to determine the role of BRAF V600E and TERT mutations in the incidence of neck lymph node (LN) metastasis in patients with papillary thyroid carcinoma (PTC).

METHODS

This was a cross-sectional study, involving PTC patients at Dr. Cipto Mangunkusumo Hospital, Jakarta. Data were obtained retrospectively based on medical records, except for BRAF V600E and TERT promoter mutations. Tumor tissue specimens of PTC's patients were transferred to the Integrated Laboratory of Faculty of Medicine, Universitas Indonesia. BRAF gene multiplication was performed with KOD One PCR Master Mix (Toyobo KMM-201), while TERT gene multiplication was performed with PCR Master Mix. Data analysis was performed with SPSS version 20. The data were analyzed using univariate and bivariate analysis with the Chi-Square test.

RESULT

42 PTC patients were included in the study; 19 (45%) had BRAF mutation, 20 (48%) had TERT mutation, and 20 (48%) had LN metastases. BRAF V600E mutation was associated with LN metastasis [p<0.001, OR = 25.33 (95% CI 4.92 - 130.34)], while TERT mutation was not. Patients with BRAF+ and TERT- mutations were 18.00 times (95% CI 2.01 - 161.05) more likely to develop LN metastasis than patients with BRAF- and TERT-. Furthermore, the presence of TERT mutation along with BRAF mutation increased the risk to 60.00 (95% CI 4.72 - 763.04) higher than patients with BRAF- and TERT-.

CONCLUSION

BRAF mutation was associated with LN metastasis in PTC patients, but not TERT mutations. However, the presence of TERT mutation in PTC's patients with BRAF mutation increased the risk of LN metastasis.

Correlation between genetic alterations and clinicopathological features of papillary thyroid carcinomas

OBJECTIVE

To investigate the correlations between multigene alterations and clinicopathological features in papillary thyroid carcinoma (PTC) samples.

METHODS

In this retrospective study, 111 cytological specimens of thyroid nodules, including 74 PTC samples and 37 benign samples, were analyzed using a 22-gene mutation assay employing next-generation sequencing. Clinicopathological information was retrospectively collected and analyzed.

RESULTS

Gene alterations were associated with a higher rate of lymph node metastasis (LNM) and thyroid capsular invasion, a lower rate of coexisting Hashimoto's thyroiditis, the classical PTC subtype, and younger age (<45 years). Among the 22 genes tested, the BRAF mutation rates showed a significant difference between the PTC and benign groups. In the subgroup analysis, younger age (odds ratio = 12.512, 95% confidence interval: 3.126-50.087) was an independent risk factor for LNM. In further analyses, BRAF mutation was significantly associated with LNM in the older subgroup (age ≥ 45 years), suggesting that the BRAF mutation test has greater value for determining PTC prognosis in the older age group.

CONCLUSIONS

Our findings will provide a more comprehensive understanding of the relationship between gene mutations and PTC and may contribute to improved PTC management.

Developing Models to Predict BRAFV600E and RAS Mutational Status in Papillary Thyroid Carcinoma Using Clinicopathological Features and pERK1/2 Immunohistochemistry Expression

The Cancer Genome Atlas (TCGA) has classified papillary thyroid carcinoma (PTC) into indolent RAS-like and aggressive BRAF-like based on its distinct driver gene mutations. This retrospective study aimed to assess clinicopathology and pERK1/2 expression variations between BRAF-like and RAS-like PTCs and establish predictive models for BRAFV600E and RAS-mutated PTCs. A total of 222 PTCs underwent immunohistochemistry staining to assess pERK1/2 expression and Sanger sequencing to analyze the BRAF and RAS genes. Multivariate logistic regression was employed to develop prediction models. Independent predictors of the BRAFV600E mutation include a nuclear score of 3, the absence of capsules, an aggressive histology subtype, and pERK1/2 levels exceeding 10% (X2 = 0.128, p > 0.05, AUC = 0.734, p < 0.001). The RAS mutation predictive model includes follicular histology subtype and pERK1/2 expression > 10% (X2 = 0.174, p > 0.05, AUC = 0.8, p < 0.001). We propose using the prediction model concurrently with four potential combination group outcomes. PTC cases included in a combination of the low-BRAFV600E-scoring group and high-RAS-scoring group are categorized as RAS-like (adjOR = 4.857, p = 0.01, 95% CI = 1.470-16.049). PTCs included in a combination of the high-BRAFV600E-scoring group and low-RAS-scoring group are categorized as BRAF-like PTCs (adjOR = 3.091, p = 0.001, 95% CI = 1.594-5.995). The different prediction models indicate variations in biological behavior between BRAF-like and RAS-like PTCs.