Method of detection of thyroid nodules: correlation with frequency of fine‐needle aspiration and malignancy rate

Thyroid Incidentalomas: Scrutinizing the Mode of Detection and Evaluating its Contribution to Thyroid Cancer Diagnosis

There is an ongoing debate about the reasons behind the increasing incidence of thyroid cancer in the last two to three decades. Here, we investigate how thyroid nodules were detected in a large series of consultations for thyroid nodular pathology.

METHODS

In total, 576 patients were analyzed, with a total of 1014 nodules described.

RESULTS

In 347 (60.2%) cases, the diagnosis of a thyroid nodule was incidental, mostly during imaging tests for other reasons. Incidental diagnosis occurred among all ranges of nodule diameter and between palpable and non-palpable cases, even within a small proportion of symptomatic cases. In univariate analysis, incidental diagnosis was associated with smaller nodule diameter, non-palpable nodules, asymptomatic cases, older patient age, less advanced stages (T1-2), and conservative management. After multivariate analysis, older age, euthyroidism, and smaller diameter were statistically significant. Incidental diagnosis contributed to the diagnosis of 53.8% of the cases of cancer. Advanced T stages (T3-4) were more common in non-incidental diagnoses.

CONCLUSION

Our results indicate that incidental diagnosis of thyroid nodules is a significant contributor to thyroid cancer diagnosis in all ranges of nodule diameter, especially at earlier stages.

Adenocarcinoma admixed with neuroendocrine carcinoma of the cervix: A case report and review of literature

A 40-year-old Ethiopian woman presented with a six-month history of non-foul-smelling whitish vaginal discharge. She also reported a one-year history of postcoital bleeding. A pelvic examination revealed a nodular, hard, and fragile cervical mass. In addition, there were nontender, firm nodules in the epigastric, periumbilical, gluteal areas, and thyroid gland. Investigations, including abdominopelvic ultrasound, magnetic resonance imaging, fine-needle aspiration cytology, and immunohistochemistry, confirmed mixed neuroendocrine carcinoma of the cervix with metastasis to the abdominal wall, gluteal area, lumbar vertebrae, and thyroid gland. The patient was started on palliative chemotherapy. Metastatic adenocarcinoma admixed with neuroendocrine carcinoma of the cervix presents a formidable disease phenotype, characterized by complex diagnostic and therapeutic obstacles. Multidisciplinary cooperation among oncologists, radiologists, pathologists, and surgeons is required to refine treatment approaches and improve patient prognoses for this uncommon and intricate malignancy.

Proportion of Malignancy and Evaluation of Sonographic Features of Thyroid Nodules Classified as Highly Suspicious Using ACR TI-RADS Criteria

OBJECTIVES

The reported malignancy rate of highly suspicious thyroid nodules based on the ACR TI-RADS criteria (TI-RADS category 5 [TR5]) varies widely. The objective of our study was to determine the rate of malignancy of TR5 nodules at our institution. We also aimed to determine the predictive values of individual sonographic features, as well as the correlation of total points assigned to a nodule and rate of malignancy.

METHODS

Our single-institution retrospective study evaluated 450 TR5 nodules that had cytology results available, in 399 patients over a 1-year period. Sonographic features and total TI-RADS points were determined by the interpreting radiologist. Statistical analyses included logistic regression models to find factors associated with increased odds of malignancy, and computing sensitivity, specificity, positive and negative predictive values of various individual sonographic features.

RESULTS

Of the 450 nodules, 95 (21.1%, 95% exact confidence interval 17.4-25.2%) were malignant. Each additional TI-RADS point increased the odds of malignancy (adjusted odds ratio 1.35, 95% confidence interval 1.13-1.60, P < .001). "Very hypoechoic" was the sonographic feature with the highest specificity and positive predictive value for malignancy (95.5 and 44.8%, respectively), while "punctate echogenic foci" had the lowest positive predictive value (20.0%).

CONCLUSIONS

The rate of malignancy of TR5 nodules at our institution was 21.1%, which is lower than other malignancy rates reported in the literature. The total number of points assigned on the basis of the TI-RADS criteria was positively associated with malignancy, which indicates that TR5 should be viewed as a spectrum of risk.

Metastasis of Mixed Adenoneuroendocrine Carcinoma of the Uterine Cervix to Thyroid Gland

The thyroid metastasis from cervical cancer is extremely rare compared to other organs. It is sometimes difficult to distinguish primary tumors from metastases, as most metastatic thyroid nodules are asymptomatic. In this case, a 54-year-old woman had undergone radical hysterectomy due to cervical tumor of stage IB1 mixed adenoneuroendocrine carcinoma (MANEC) 5 years ago. After 3 years, ultrasound examination revealed a suspicious malignant nodule in the left lobe of thyroid gland at regular postoperative follow-up. This patient had no obvious clinical symptoms. The ultrasonography (US)-guided core needle biopsy (CNB) of the thyroid nodule was performed on the patient. The immunohistochemistry analyses revealed that it was poorly differentiated small-cell neuroendocrine carcinoma (SCNEC). Subsequently, the patient underwent left hemithyroidectomy plus isthmusectomy. The postoperative pathology and immunohistochemistry, combining with clinical history, confirmed that the thyroid nodule was a metastasis from cervical MANEC. Conventional chemotherapy and regular follow-up were carried out after the operation. The patient was readmitted 1 year later for pancreatic metastatic lesions and died 1 month after surgery. Early detection of metastatic cancer is potentially helpful, and when necessary, ultrasound-guided puncture biopsy can be utilized to further diagnose metastatic thyroid cancer.

Triggers of thyroid cancer diagnosis: a systematic review and meta-analysis

PURPOSE

Understanding the method of thyroid cancer detection has potential implications on interpreting incidence rates, the diagnosis and management of thyroid cancer. We conducted a systematic review of studies reporting methods of thyroid cancer detection to estimate the frequency of incidentally found cancers and classify triggers of incidental thyroid cancer diagnosis.

METHODS

We searched multiple bibliographic databases from inception to June 2020. A pair of reviewers, working independently and in duplicate selected studies for inclusion, extracted data, and evaluated each trial's risk of bias. Studies enrolling patients older than 18 years with thyroid cancer confirmed histologically were included.

RESULTS

In total, 17 cohorts and 1 cross-sectional study, conducted between 1991 and 2018, enrolling 4668 patients with thyroid cancer were included: 88% had papillary thyroid cancer and 23% had papillary thyroid microcarcinoma. The proportion of patients with non-incidental and incidental thyroid cancer was similar: 49% [95% confidence interval (CI): 40-58%]. Subgroup analysis showed that most patients with incidental thyroid cancers had tumor size <10 mm (76%; 95% CI: 56-92%), age >45 (61%; 95% CI: 56-67%), and were detected through imaging (35%; 95% CI: 26-45%), of which ultrasound was the most common modality (27%; 95% CI: 14-43%). The heterogeneity for all the effect sizes was large and significant.

CONCLUSIONS

About half of thyroid cancers were found incidentally through the use of imaging studies, in particular neck ultrasound. These incidentally found cancers were mostly small papillary thyroid cancer. These results highlight opportunities for interventions aimed at reducing drivers of overdiagnosis.

Ultrasound-guided fine-needle aspiration biopsy of thyroid nodules

Fine needle aspiration biopsy (FNAB) remains crucial in the evaluation of thyroid nodules with suspicious clinical findings or ultrasound (US) features suggestive of malignancy. The use of US-guidance for FNAB allows real-time visualization of the needle, but is also highly operator-dependent. Physicians from many specialties (endocrinologists, otolaryngologists/endocrine surgeons, nuclear medicine physicians, radiologists, and pathologists) are involved in the diagnostic workup of thyroid nodules and a standardized and meticulous technique for US-FNAB is essential for lowering the yield of nondiagnostic specimens and false-negative results. This video, therefore, demonstrates a well-proved technique and technical tips to increase the diagnostic results from US-FNAB.

Managing uncommon and unexpected findings during neuromuscular ultrasound

One barrier to widespread adoption of neuromuscular ultrasound by clinical neurophysiologists is concern over how to identify and manage non-neuromuscular findings. This review addresses this concern by describing the sonographic appearance of a variety of commonly observed pathologies and anatomic variants in dermal, subcutaneous, bony, glandular, lymphatic, vascular, and other superficial tissues. Additionally, it outlines techniques to ensure proper clinical and ultrasound evaluation of unexpected or uncommon findings. Finally, it highlights strategies to manage unexpected findings, including how to best communicate findings to patients and referring clinicians to avoid unnecessary testing and ensure appropriate follow-up. Ultrasound extends the ability of the neuromuscular sonographer-clinician to contribute to patient care.

Ultrasonographic characteristics of thyroid metastasis from clear cell renal cell carcinoma: A case report

INTRODUCTION

Thyroid metastasis from clear cell renal cell carcinoma (ccRCC) is a very rare condition, and its ultrasonographic characteristics have not been summarized in the literature. We herein report a case of thyroid metastasis from ccRCC that occurred 11 years after the surgery and the ultrasonographic characteristics of it are described.

PATIENT CONCERNS

A 57-year-old male patient was admitted to our hospital in September 2018 due to discomfort in the neck. No other abnormalities were found during laboratory examination of thyroid function. The previous medical history of the patient included a right nephrectomy for the treatment of ccRCC in June 2007.

DIAGNOSIS

Ultrasound examinations revealed multiple thyroid nodules. After nephrectomy, there was no obvious abnormality in the right renal area. Computed tomography (CT) showed an oval lesion with slightly lower density in the right lobe of the thyroid, and the patient was initially diagnosed with nodular goiter.

INTERVENTIONS

Bilateral partial thyroidectomy under general anesthesia was conducted. Intraoperative frozen pathological examination showed clear cell carcinoma in the right lobe of the thyroid gland. Therefore, total thyroidectomy and lymph node dissection in the central neck area were performed.

OUTCOMES

The patient underwent surgical treatment and recovered successfully. The patient was followed up for 2 years with no further metastasis.

CONCLUSION

Ultrasound examination is a safe and convenient screening method. For patients with a renal malignant tumor, if the ultrasound image of thyroid nodule is found to have the characteristics of malignant tumors, the occurrence of metastasis of renal cancer to the thyroid should be highly suspected. Core needle biopsy (CNB) and histopathological diagnosis should be conducted subsequently for early diagnosis.

[Accuracy of two thyroid imaging, reporting and data systems for differential diagnosis of benign and malignant thyroid nodules]

OBJECTIVE

To compare the accuracy of two widely used thyroid imaging, reporting and data systems (TI-RADS), namely ACR TI-RADS and Kwak TI-RADS, in the differential diagnosis of benign and malignant thyroid nodules.

METHODS

We reviewed the data of 350 thyroid nodules with definite diagnoses by surgical histopathology (n=144, 41.14%) or fine needle aspiration (FNA) cytopathology (n=206, 58.86%). The nodules were graded using ACR TI-RADS and Kwak TI-RADS based on the ultrasound images, and the diagnostic accuracy of these two systems was evaluated by the area under the receiveroperating characteristic curve (AUC).

RESULTS

The AUCs of ACR TI-RADS and Kwak TI-RADS were both 0.879. For a differential diagnosis of the thyroid nodules, ACR TI-RADS had a diagnostic sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, Youden's index and accuracy of 77.3%, 89.1%, 83.0%, 85.1%, 7.101, 0.255, 27.848, 0.664 and 0.843, respectively, with an optimal threshold of TR5, as compared with 84.8%, 84.0%, 78.3%, 89.0%, 5.283, 0.181, 29.265, 0.688 and 0.843, respectively, of Kwak TI-RADS, which had an optimal threshold of 4c.

CONCLUSIONS

Both ACR TI-RADS and Kwak TI-RADS have good performance for differential diagnosis of thyroid nodules, but ACR TI-RADS has a higher specificity and a lower sensitivity compared with Kwak TI-RADS.