Thyroid Nodule Size as a Predictor of Malignancy in Follicular and Hurthle Neoplasms

INTRODUCTION

The management of follicular (FN) and Hurthle cell neoplasms (HCN) is often difficult because of the uncertainty of malignancy risk. We aimed to assess characteristics of benign and malignant follicular and Hurthle neoplasms based on their shape and size.

MATERIALS AND METHODS

Patients with Follicular adenoma (FA) or carcinoma (FC) and Hurthle Cell adenoma (HCA) or carcinoma (HCC) who had preoperative ultrasonography were included. Demographic data were retrieved. Size and shape of the nodules were measured. Logistic regression analyses and odds ratios were performed.

RESULTS

A total of 115 nodules with 57 carcinomas and 58 adenomas were included. Logistic regression analysis shows that the nodule height and the patient age are predictors of malignancy (p-values = 0.001 and 0.042). A cutoff value of nodule height ≥ 4 cm. produces an odds ratio of 4.5 (p-value = 0.006). An age ≥ 55 year-old demonstrates an odds ratio of 2.4-3.6 (p-value = 0.03). Taller-than-wide shape was not statistically significant (p-value = 0.613).

CONCLUSION

FC and HCC are larger than FA and HCA in size, with a cutoff at 4 cm. Increasing age increases the odds of malignancy with a cutoff at 55 year-old. Taller-than-wide shape is not a predictor of malignancy.

Incidentally Detected Thyroid Follicular Neoplasm on Somatostatin Receptor Imaging and Post-therapy Scan

Peptide receptor radionuclide therapy (PRRT) either using Lu-177 or Y-90 peptide radiopharmaceuticals has emerged as promising treatment modality in patients with inoperable metastatic neuroendocrine tumour (NET) including medullary thyroid cancer, because of overexpression of somatostatin receptor 2 (sstr-2) on these cells. The several investigators have used PRRT in non-iodine avid differentiated thyroid cancer patients with limited success, where other treatment modalities have failed, probably due to faint sstr-2 expression in these lesions. However Hurthle cell neoplasms being predominantly non-iodine avid lesions have shown sstr-2 over-expression. The present case of inoperable NET patient imaged and treated with radiolabelled somatostatin analogue showed incidentally detected thyroid lesion highlighting the its importance in imaging and treatment in these type of thyroid malignancies.

Functional polymorphisms in antioxidant genes in Hurthle cell thyroid neoplasm - an association of GPX1 polymorphism and recurrent Hurthle cell thyroid carcinoma

Background

Hurthle cells of the thyroid gland are very rich in mitochondria and oxidative enzymes. As a high level oxidative metabolism may lead to higher level of oxidative stress and can be associated with an increased risk for cancer, we investigated whether common functional polymorphisms in antioxidant genes (SOD2, CAT, GPX, GSTP1, GSTM1 and GSTT1) are associated with the development or clinical course of Hurthle cell thyroid carcinoma (HCTC).

Methods

A retrospective study was performed in 139 patients treated by thyroid surgery for a Hurthle cell neoplasm. HCTC, Hurthle cell thyroid adenoma (HCTA) or Hurthle cell thyroid nodule (HCTN) were diagnosed by pathomorphology. DNA was extracted from cores of histologically confirmed normal tissue obtained from formalin-fixed paraffin-embedded specimens and genotyped for investigated polymorphisms. Logistic regression was used to compare genotype distributions between patient groups.

Results

HCTC, HCTA and HCTN were diagnosed in 53, 47 and 21 patients, respectively. Metastatic disease and recurrence of HCTC were diagnosed in 20 and 16 HCTC patients, respectively. Genotypes and allele frequencies of investigated polymorphisms did not deviate from Hardy-Weinberg equilibrium in patients with HCTC, HCTA and HCTN. Under the dominant genetic model we observed no differences in the genotype frequency distribution of the investigated polymorphisms when the HCTA and HCTN group was compared to the HCTC group for diagnosis of HCTC or for the presence of metastatic disease. However, GPX1 polymorphism was associated with the occurrence of recurrent disease (p = 0.040).

Conclusions

GPX1 polymorphism may influence the risk for recurrent disease in HCTC.

Fine needle aspiration cytology of Hashimoto's thyroiditis - A diagnostic pitfall with review of literature

Hashimoto's thyroiditis is the second most common thyroid lesion next to goiter diagnosed on fine needle aspiration cytology (FNAC). It is also an important cause for hypothyroidism. FNAC plays a significant role in the diagnosis of thyroid lesions due to its simplicity and low cost. It can accurately diagnose Hashimoto's thyroidits in most patients. However, a small percentage of cases may be missed due to the inherent limitations of this procedure and the varied cytomorphology of this lesion. Therefore thorough cytological evaluation and an integrated approach are necessary to pick up correct diagnosis and to avoid unnecessary surgery. We present a 56-year-old female with solitary thyroid nodule diagnosed as Hurthle cell neoplasm on FNAC, but subsequent histopathological diagnosis following resection revealed Hashimoto's thyroiditis with marked Hurthle cell change.