Preoperative evaluation of thyroid nodules - Diagnosis and management strategies

Thyroid cancer is the most common endocrine malignancy, with increasing incidence over the past few decades. Fine needle aspiration (FNA) biopsy is the gold standard for preoperative diagnosis of thyroid malignancies. Nevertheless, this method renders indeterminate results in up to 30% of the cases. Therefore, these patients are often referred to unnecessary surgery to establish the diagnosis. To improve the accuracy of preoperative diagnosis, several other ways, such as ultrasonography, elastography, immunohistochemical analysis, genetic testing, and core needle biopsy, have been developed and can be used either in association with or as an alternative to FNA. This review aims to evaluate all these diagnostic tools to determine the most appropriate way of managing thyroid nodules and subsequently improve the selection of cases referred to surgery.

Distribution of Functional Status of Thyroid Nodules and Malignancy Rates of Hyperfunctioning and Hypofunctioning Thyroid Nodules in Germany

AIM

Thyroid scintigraphy enables the depiction of the functional status of thyroid nodules (TNs) with both, ^99mTc-pertechnetate and ¹²³Iodine. The functional status is relevant for diagnostic procedures for the differentiation of benign and malignant TNs. The aim of this study was to examine the current frequencies of hyper-, hypo- and isofunctioning TNs in Germany and to estimate the risk of malignancy with regard to functional status.

METHODS

In 11 study centers, a minimum of 100 nodules per center were consecutively enrolled between July 2019 and April 2020. Inclusion criteria were: newly diagnosed nodule, nodule' size of 10 mm or more, thyroid scintigraphy. Exclusion criteria were: completely cystic TNs, patients with prior radioiodine therapy or thyroid surgery. The risk of malignancy was estimated for hyper- and hypofunctioning TNs.

RESULTS

Overall, 849 patients (72 % women) with 1262 TNs were included. Patients' age ranged from 18 to 90 years. Most TNs were hypofunctioning (n=535, 42%) followed by isofunctioning TNs (n=488, 39%) and hyperfunctioning TNs (n=239, 19%). When only TNs with a maximum size of 2 cm or more were considered the rate of hyperfunctioning and hypofunctioning TNs increased (to 27% and 49%) while isofunctioning TNs decreased. Only one of all hyperfunctioning TNs was malignant. In hypofunctioning nodules, the malignancy rate was estimated at 10%.

CONCLUSION

In Germany, the proportion of hyperfunctioning TNs is approximately 20% and increases in larger TNs to up to 27%. Due to the low risk of malignancy in hyperfunctioning TNs, no further procedures to rule out malignancy are necessary. The risk of malignancy of hypofunctioning TNs is significantly higher. Thus, a thyroid scintigraphy is a useful diagnostic tool in Germany.

Clinical, sonographical and cytological comparison of toxic and non-toxic thyroid nodules

Aim: To compare patients with toxic and non-toxic nodular/multinodular goiter in terms of clinical, sonographical and cytological features. Material and Method: The medical data of 326 patients were reviewed retrospectively. Clinical and sonographic features were examined. Four hundred and eighty-one nodules were compared sonographically and cytologically. One hundred twenty-four patients had toxic nodular goiter and 202 of them had non-toxic nodular goiter. Results: The toxic nodular goiter group was older, they had more male sex, more multi-nodularity, larger thyroid glands and nodules with more sonographically suspicious features (p 40 mm in 13.9% of the nodules in the toxic group and 5.4% of those in the non-toxic group (p= 0.003). Central vascularization (p

Incidence and Risk Factors of Thyroid Malignancy in Patients with Toxic Nodular Goiter

Background. Although hyperfunctioning thyroid disorders were thought to be protective against malignancy, some recent studies reported a high incidence of incidentally discovered cancer in patients with hyperfunctioning benign thyroid disorders. We performed this study to estimate the incidence and predictors of malignant thyroid disease in patients with toxic nodular goiter (TNG). Patients and Methods. The data of 98 patients diagnosed with TNG were reviewed (including toxic multinodular goiter SMNG and single toxic nodule STN). The collected data included patients age, gender, systemic comorbidities, family history of thyroid malignancy, previous neck radiation, type of disease (multinodular or single), size of the dominant nodule by the US, operative time, and detection of significant lymph nodes during operation. Based on the histopathological analysis, the cases were allocated into benign and malignant groups. Results. Malignancy was detected in 21 patients (21.43%). Although age distribution was comparable between the two groups, males showed a significant increase in association with malignancy. Medical comorbidities and family history of cancer did not differ between the two groups. However, TMNG showed a statistically higher prevalence in the malignant group. Operative data, including operative time and lymph node detection, were comparable between the two groups. On regression analysis, both male gender and TMNG were significant predictors of malignancy. Conclusion. The presence of thyroid hyperfunction is not a protective factor against malignancy, as malignancy was detected in about 1/5 of cases. Male gender and TMNG were significant risk factors of malignancy in such patients.

Simultaneous hot and cold thyroid nodules: Which is malignant?

Physicians should be aware of the risk of malignancy in patients with toxic multinodular goiter. Radionuclide scan cannot be used to predict the malignant potential of thyroid nodules. A comprehensive evaluation of imaging studies is needed.

Malignancy risk of hyperfunctioning thyroid nodules compared with non-toxic nodules: systematic review and a meta-analysis

Background

Hyperfunctioning or hot nodules are thought to be rarely malignant. As such, current guidelines recommend that hot nodules be excluded from further malignancy risk stratification. The objective of this systematic review and meta-analysis is to compare the malignancy risk in hot nodules and non-toxic nodules in observational studies.

Methods

Ovid MEDLINE Daily and Ovid MEDLINE, EMBASE, Scopus, and Web of Science databases were searched. Observational studies which met all of the following were included: (1) use thyroid scintigraphy for nodule assessment, (2) inclusion of both hyperfunctioning and non-functioning nodules based on scintigraphy, (3) available postoperative histopathologic nodule results, (4) published up to November 12, 2020 in either English or French. The following data was extracted: malignancy outcomes include malignancy rate, mapping of the carcinoma within the hot nodule, inclusion of microcarcinomas, and presence of gene mutations.

Results

Among the seven included studies, overall incidence of malignancy in all hot thyroid nodules ranged from 5 to 100% in comparison with non-toxic nodules, 3.8–46%. Odds of malignancy were also compared between hot and non-toxic thyroid nodules, separated into solitary nodules, multiple nodules and combination of the two. Pooled odds ratio (OR) of solitary thyroid nodules revealed a single hot nodule OR of 0.38 (95% confidence interval (CI) 0.25, 0.59), toxic multinodular goiter OR of 0.51 (95% CI 0.34, 0.75), and a combined hot nodule OR of 0.45 (95% CI 0.31, 0.65). The odds of malignancy are reduced by 55% in hot nodules; however, the incidence was not zero.

Conclusions

Odds of malignancy of hot nodules is reduced compared with non-toxic nodules; however, the incidence of malignancy reported in hot nodules was higher than expected. These findings highlight the need for further studies into the malignancy risk of hot nodules.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13044-021-00094-1.

[The "hot" thyroid gland carcinoma and a critical look at thermal ablation]

Hot and hyperfunctioning thyroid gland nodules are currently treated primarily by radioiodine or surgical resection. In recent years local thermal ablation as an alternative therapeutic modality is increasingly recommended. This article reports the case of a patient with a hot thyroid nodule, which was resected and turned out to be follicular thyroid cancer. In this context it appears to be necessary to critically question thermal ablation as an alternative treatment option for thyroid nodules, particularly since the current recommendations are weak with low or even very low evidence. Radioiodine or surgery remains the first-line treatment for hot and hyperfunctioning thyroid nodules but malignancy in a hot thyroid nodule also needs to be considered.

The value of ultrasonography for the indication of fine-needle aspiration in autonomous thyroid nodules

BACKGROUND

The risk of malignancy in autonomous thyroid nodules is considered to be very low in adults and fine-needle aspiration (FNA) is not recommended in these cases; however, some studies contest this. Just as ultrasonography (US) has been used to select nonautonomous nodules with initial benign cytology that deserve FNA repetition, this method may also be useful to select autonomous nodules that are candidates for FNA.

METHODS

In this prospective study, FNA was obtained in 48 adults patients with autonomous solitary nodules >1 cm with suspicious US features (at least two of the following findings: hypoechogenicity, microcalcification, irregular margins, taller than wider shape, predominantly or exclusively central vascularization).

RESULTS

Cytology was benign in 28 patients (58.3%). Six patients (12.5%) had nondiagnostic cytology and histology revealed benign nodules in these cases. Cytology was indeterminate in nine other patients (18.5%). Of these, seven were adenomas and two were follicular carcinomas on histology. Finally, cytology suspicious for malignancy or malignant cytology was detected in five patients (10.4%), all of them confirmed histologically to be papillary carcinomas (the follicular variant in three). Thus, the frequency of malignancy was 14.6% (two follicular carcinomas and five papillary carcinomas), 8.3% in nodules with two suspicious findings vs 33.3% in nodules with ≥3 suspicious findings (P = .055).

CONCLUSION

The results suggest that the presence of ultrasonographic findings suspicious for malignancy in autonomous thyroid nodules >1 cm is a criterion for the indication of FNA.