Follicular thyroid carcinoma with an eggshell calcification: report of 3 cases

Comparison of the diagnostic performance of three ultrasound thyroid nodule risk stratification systems for follicular thyroid neoplasm: K-TIRADS, ACR -TIRADS and C-TIRADS

OBJECTIVE

To explore the diagnostic performance of the currently used ultrasound-based thyroid nodule risk stratification systems (K-TIRADS, ACR -TIRADS, and C-TIRADS) in differentiating follicular thyroid adenoma (FTA) from follicular thyroid carcinoma (FTC).

METHODS

Clinical data and preoperative ultrasonographic images of 269 follicular thyroid neoplasms were retrospectively analyzed. All of them were detected by Color Doppler ultrasound instruments equipped with high-frequency liner array probes (e.g. Toshiba Apoli500 with L5-14MHZ; Philips IU22 with L5-12MHZ; GE LOGIQ E9 with L9-12MHZ and MyLab Class C with L9-14MHZ). The diagnostic performance of three TIRADS classifications for differentiating FTA from FTC was evaluated by drawing the receiver operating characteristic (ROC) curves and calculating the cut-off values.

RESULTS

Of the 269 follicular neoplasms (mean size, 3.67±1.53 cm), 209 were FTAs (mean size, 3.56±1.38 cm) and 60 were FTCs (mean size, 4.07±1.93 cm). There were significant differences in ultrasound features such as margins, calcifications, and vascularity of thyroid nodules between the FTA and FTC groups (P < 0.05). According to the ROC curve comparison analysis, the diagnostic cut-off values of K-TIRADS, ACR-TIRADS, and C-TIRADS for identifying FTA and FTC were K-TR4, ACR-TR4, and C-TR4B, respectively, and the areas under the curves were 0.676, 0.728, and 0.719, respectively. The difference between ACR-TIRADS and K-TIRADS classification was statistically significant (P = 0.0241), whereas the differences between ACR-TIRADS and C-TIRADS classification and between K-TIRADS and C-TIRADS classification were not statistically significant (P > 0.05).

CONCLUSION

The three TIRADS classifications were not conducive to distinguishing FTA from FTC. It is necessary to develop a novel malignant risk stratification system specifically for the identification of follicular thyroid neoplasms.

Prediction of follicular thyroid carcinoma associated with distant metastasis in the preoperative and postoperative model

BACKGROUND

Only clinicopathological findings are reported for predicting follicular thyroid carcinoma (FTC) associated with distant metastasis, and preoperative ultrasound (US) findings are unknown.

METHODS

Associations between distant metastases of FTC and predicting factors were evaluated by using logistic regression analysis in the preoperative and postoperative models.

RESULTS

Distant metastasis was present in 37 (11.5%) of the 321 patients with FTC. In the preoperative model, independent predictors of distant metastasis were age, marked hypoechogenicity, nodule-in-nodule appearance, and rim calcification on US. Postoperative predictors were marked hypoechogenicity, rim calcification, and widely invasive histology. Sensitivities, specificities, and the area under the curves for predicting distant metastasis were 86.5%, 80.3%, and 0.889 on preoperative status and 86.5%, 78.5%, and 0.908 on postoperative status. Although not statistically significant, all four patients with gross extrathyroidal extension had metastasis.

CONCLUSION

Age, ultrasound features, and widely invasive histology allow preoperative and postoperative prediction of FTC associated with distant metastasis.

An Unusual Presentation of a Large Calcified Thyroid Nodule

This case highlights the rare occurrence of a large benign calcified nodule of the left lobe of the thyroid gland with associated obstructive symptoms. Unusually, the calcification was confluent with similar calcified nodules in the subcutaneous tissue plane. The symptoms were alleviated following a total thyroidectomy.

Subclassification of Bethesda Atypical and Follicular Neoplasm Categories According to Nuclear and Architectural Atypia Improves Discrimination of Thyroid Malignancy Risk

BACKGROUND

Although The Bethesda System for Reporting Thyroid Cytopathology has provided clinicians with a standardized classification scheme for the diagnosis of thyroid fine-needle aspiration cytology (FNAC) specimens, the indeterminate categories of Bethesda III (B3)-atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS)-and Bethesda IV (B4)-follicular neoplasm/suspicious for follicular neoplasm (FN/SFN)-continue to pose challenges with regards to ideal diagnostic and therapeutic management. Having previously demonstrated the presence of nuclear atypia as a high-risk subgroup in B3, the objective of this study was to evaluate the malignancy rates in the B4 subgroup with nuclear atypia.

METHODS

A retrospective review of all thyroid FNACs diagnosed as B4 (FN/SFN) between 2008 and 2015 was conducted at a tertiary referral center in Singapore. Data on patient demographics, sonographic features, and final histological diagnosis were collected. This was compared to data from a previous analysis on all nodules diagnosed as B3 (AUS/FLUS) over a similar period.

RESULTS

A total of 137/309 (44.3%) and 88/111 (79.3%) FNACs diagnosed as B3 and B4, respectively, underwent surgical excision yielding final histopathological diagnoses. The malignancy rate of B4 was 31/88 (35.2%) compared to B3, which was 37/137 (27.0%). Subclassification based on the presence of architectural versus nuclear atypia showed significantly higher malignancy rates in B4 nodules with nuclear atypia (21.8% vs. 57.6%; p < 0.01). These findings corroborate previous results within the B3 category (malignancy rate of 14.7% vs. 36.8%; p < 0.01). The only sonographic features predictive of malignancy were the presence of macrocalcifications in B4 compared to irregularity of margins in B3.

CONCLUSION

The presence of nuclear atypia identifies subgroups with significant differential malignancy risks within both the B3 and B4 categories. This supports the notion that subclassification is a useful risk stratification tool that can guide diagnostic and therapeutic management of indeterminate thyroid nodules with heterogenous risk profiles.

Thyroid Cancer: Ultrasound Imaging and Fine-Needle Aspiration Biopsy

Ultrasound is critical in detection, diagnosis, and management of thyroid nodules. Ultrasound detection of regional nodal metastatic disease is based on abnormal nodal morphology rather than size and is critical to initial surgical and long-term management of thyroid cancer. Fine-needle aspiration biopsy is the gold standard for malignancy diagnosis in thyroid cancer. Thyroglobulin assay of nodal aspirates improves accuracy in diagnosis of metastases. Reporting lexicons assign risk levels to thyroid nodules with the goal of improving and standardizing patient management. Surveillance ultrasound in papillary microcarcinomas is being evaluated and compared with surgical management.

Primary follicular thyroid carcinoma metastasis to the kidney and widespread dissemination: A case report

Distant metastases are more common in follicular thyroid carcinoma (FC) than in papillary thyroid carcinoma. However, FC metastasis to the kidney with eggshell calcification, as observed in the present case, is rare. The current report presents a case of a 67-year-old woman exhibiting a solitary tumor in the mid pole of the left kidney. Radical nephrectomy was performed, as the tumor was diagnosed as a primary renal carcinoma using contrast-enhanced computed tomography. Once the tumor was confirmed to be FC, total thyroidectomy was performed. Following administration of an oral therapeutic dose of 100 mCi ¹³¹I, functional imaging demonstrated the presence of multifocal metastases in the chest and abdomen. Euthyrox^® was prescribed orally to aid normal thyroid function. Follow-up 6 months later using radionuclide imaging demonstrated the disappearance of the multifocal metastases in the chest and abdomen. The distant metastasis of FC may represent the initial symptom of the primary lesion, which was neglected. Ultrasound is an effective method to examine nodules located on the thyroid.

Follicular thyroid carcinoma with predominantly cystic formation presenting initially with multiple distant metastases

Primary malignancies presenting with multiple distant metastases include lung cancer, gastrointestinal malignancy, breast cancer, and prostatic cancer. Multiple distant metastases from follicular thyroid carcinoma (FTC) are uncommon. Cystic formation in FTC is an atypical finding in ultrasonography. The cystic formation of a thyroid nodule is usually considered a benign sonographic finding. We report the case of a 78-year-old man who presented with multiple distant metastases from an FTC with a predominantly cystic formation.

Hürthle cell thyroid adenoma with an eggshell calcification: sonographic-pathologic correlation

We report the sonographic pathologic correlation in a case of Hürthle cell thyroid adenoma with an eggshell calcification in a 58-year-old woman. The mass was hypoechoic with a continuous eggshell calcification on gray-scale sonographic and intranodular vascularity power Doppler imaging. At pathological examination, the dystrophic calcification of eggshell type was located between the intact fibrous capsule and the main tumor matrix. Hürthle cell adenoma should be included in the differential diagnosis of a thyroid nodule with an eggshell calcification.

Sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma

OBJECTIVES

The purpose of this study was to determine the sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma.

METHODS

This retrospective study included 36 pathologically proven follicular carcinomas (5 widely invasive and 31 minimally invasive) and 52 follicular adenomas in 88 patients who underwent thyroid surgery. We analyzed the sonographic features of each tumor, including maximum diameter, peripheral halo, echogenicity, echo texture, calcifications, and nodularity. The frequencies of the sonographic features were compared by χ(2) and Fisher exact tests between follicular adenomas and carcinomas. The relative risk of malignancy was evaluated by logistic regression analysis.

RESULTS

Predominantly solid contents, hypoechoic echogenicity, a heterogeneous echo texture, the presence of calcifications, and an absent or irregular thick halo were associated with follicular carcinoma (P < .05). Logistic regression analysis demonstrated that predominantly solid contents, a heterogeneous echo texture, and the presence of calcifications were associated with significant increases in the relative risk of follicular carcinoma (odds ratios, 9.4, 24.9, and 25.6, respectively; P < .01).

CONCLUSIONS

Sonography could provide useful information for differentiating follicular carcinoma from follicular adenoma.

Fine-needle aspiration of thyroid nodules with macrocalcification

BACKGROUND

The presence of microcalcification is highly suggestive of malignancy; however, the association of macrocalcification with cancer remains unclear and controversial. The purpose of this study was to evaluate the diagnostic yield and accuracy of ultrasound (US)-guided fine-needle aspiration (FNA) of thyroid nodules with macrocalcifications and to investigate the association between macrocalcification subtype and malignancy risk.

METHODS

We retrospectively reviewed sonographic findings and pathologic results of thyroid nodules with macrocalcification in patients who underwent US-guided FNA in our hospital from January 2009 through December 2010. Inclusion criteria were as follows: (i) malignant or benign nodules confirmed on histologic examination of surgical specimens after US-guided FNA and (ii) nodules not histologically confirmed that were subjected to FNA at least twice and follow-up US examinations for 2 years. Thyroid nodules with macrocalcification were classified into four groups: smooth total (eggshell) calcification, smooth partial calcification, irregular calcification, and nodular calcification. The diagnostic yield of FNA for thyroid nodules with macrocalcification was determined by cytology. Sensitivity, specificity, and diagnostic accuracy of preoperative FNA cytology were calculated and compared with those of histologic examination of surgical specimens.

RESULTS

There were 188 nodules with macrocalcification in 167 patients; of these, 95 were benign, 80 were malignant, and 13 were nondiagnostic. The diagnostic yield of FNA for thyroid nodules with macrocalcification was 93.08%. Sensitivity, specificity, positive predictive value, and negative predictive value were 98.51%, 90.91%, 95.65%, and 96.77%, respectively. The false-positive value and false-negative value were 9.09% and 1.49%, respectively. The diagnostic accuracy was 96%. There was no statistically significant difference in the association between macrocalcification subtype and malignancy risk (p > 0.05).

CONCLUSIONS

Macrocalcification associated with thyroid nodules is not a reliable criterion for malignancy. FNA of thyroid nodules with macrocalcification had a high diagnostic yield and a reliable accuracy. Consistency between cytology and histology was almost perfect. Therefore, FNA is a good screening method for malignancy of thyroid nodules with macrocalcification.

Management of thyroid incidentalomas encountered by anesthesiologists and pain physicians

Unexpected, asymptomatic thyroid lesions incidentally discovered during unrelated diagnostic or therapeutic interventions are called thyroid incidentalomas (TIs). These lesions are extremely common, creating a clinical problem that most anesthesiologists and pain specialists are unfamiliar with. Ultrasonography (US), which allows high-quality real-time visualization of tissues during brachial plexus block, stellate ganglion block, central vascular access, and other interventions, is the imaging modality of choice of many anesthesiologists and pain medicine specialists for therapeutic interventions on the neck. The increasing number of US procedures performed on the neck will eventually result in an upsurge of anesthesiologists and pain specialists encountering a TI. Interventionalists are responsible for acquiring optimal images, accurate needle positioning during interventions, and storage and appropriate labeling of the obtained images. Ignoring the TI or disclosing the presence of a "tumor" can substantially affect the patient's well-being. In this literature review, we discuss 2 clinical cases of incidentalomas, summarize the current evidence-based strategies, and provide readers with practical guidelines-possibly applicable to other abnormal findings-for the management of incidentally found thyroid lesions.

An unusual presentation of a calcified thyroid gland

A multinodular goitre with cystic degeneration with haemorrhage and subsequent calcification is a common occurrence in long-standing multinodular goitres. But extensive enlargement and calcification causing obstructive symptoms including dysphagia and tracheal shift has not been commonly reported in the literature. Our patient, an 82-year-old man presented with long-standing dysphagia and tracheal shift. His case proved challenging with the retrosternal location of the calcified gland, needing a collar neck incision and a manubriotomy to assess the thyroid. There was a large calcified shell to the gland that made mobilising and removing the gland very difficult. Histology revealed a large multinodular goitre with a large calcified cyst representing previous cyst haemorrhage which underwent calcification. Symptoms resolved postsurgical intervention.

Thyroid incidentalomas: to treat or not to treat

Incidental lesions of the thyroid gland are an increasing problem facing clinicians. While asymptomatic palpable lesions are detected in only 4-7% of the population, currently available imaging modalities are sensitive enough to detect lesions in 20-30% of the population. Guidelines for managing these incidentalomas are limited, largely due to lack of well-powered prospective studies. This review will address the currently available data on thyroid incidentalomas, detected through clinical examination, cross-sectional imaging, ultrasound, and PET scans. We will focus on the modalities of detection and risk of malignancy, further investigation and management options and the deficiencies therein. We propose a pragmatic algorithm when faced with this clinical dilemma under differing circumstances.