The Role of Core Needle Biopsy for Thyroid Nodules with Initially Indeterminate Results on Previous Fine-Needle Aspiration: A Systematic Review and Meta-Analysis

Core needle biopsy for thyroid nodules assessment-a new horizon?

Ultrasound-guided fine-needle aspiration is the standard for evaluating thyroid nodules with a high safety profile and a relatively low number of non-diagnostic cytological findings. Nevertheless, this diagnostic method traditionally has its weak points. Several diagnostic categories such as Bethesda I, III and IV are not reliable for thyroid carcinoma risk assessment. Recent advancements in a core needle biopsy made it possible to use this tool as a new method for thyroid nodules evaluation. The main feature of this method is the use of thin needles (18-21G) and guns with an automatic trigger mechanism. The histological material collected with the use of a core needle biopsy is usually superior to cytological. Therefore, the core needle biopsy can be used as a complementary technique to a standard fine needle aspiration in difficult and dubious cases of thyroid neoplasia with uncertain malignant potential.

Core Needle Biopsy in the Diagnosis of Thyroid Nodules

BACKGROUND

Core needle biopsy (CNB) is a relatively new technique for the diagnosis of thyroid nodules, and there are currently no large clinical series available. CNB results from 3000 cases are presented in this article.

METHODS

A spring-loaded 20-gauge needle was used for CNB under local anesthesia and ultrasonography guidance for 3000 patients with nodular goiter (584 males, 2416 females, mean age: 48.5). One physician performed all biopsy procedures without conducting on-site pathological examinations.

RESULTS

There were non-diagnostic 22 (.7%), benign 2620 (87.4%), atypia of undetermined significance and/or, follicular lesion of undetermined significance 90 (3%), follicular neoplasms and/or suspicious for follicular neoplasm 53 (1.7%), suspicious for malignancy 160 (5.4%), and malignant 55 (1.8%) cases. The CNB procedure was repeated in 19 non-diagnostic cases, and 17 of these patients were benign and two had malignancy. Thyroidectomy was performed on patients who had malign CNB results. All final pathology reports, except for one, were malignant for the patients who had malignant CNB results. The specificity and the sensitivity of CNB were found to be 99.9% and 100%, respectively. There were no serious complications.

CONCLUSION

In thyroid nodules, core needle biopsy is a highly sensitive, specific, and reliable method that could be performed by a single physician. It does not require on-site pathological analysis and has a low incidence of complications and non-diagnostic rates.

Management of Thyroid Nodules

Thyroid nodules are common and the prevalence varies between 4 and 7% by palpation and 19-68% by high-resolution USG. Most thyroid nodules are benign, and the malignancy rate varies between 7 and 15% of patients. Thyroid nodules are detected incidentally during clinical examination or, more often, during imaging studies performed for another reason. All detected thyroid nodules should be evaluated clinically. The main test in evaluating thyroid function is thyroid stimulating hormone (TSH). If the serum TSH level is below the normal reference range, a radionuclide thyroid scan should be performed to determine whether the nodule is hyperfunctioning. If the serum TSH level is normal or high, ultrasonography (US) should be performed to evaluate the nodule. US is the most sensitive imaging method in the evaluation of thyroid nodules. Computed tomography (CT) and magnetic resonance imaging are not routinely used in the initial evaluation of thyroid nodules. There are many risk classification systems according to the USG characteristics of thyroid nodules, and the most widely used in clinical practice are the American Thyroid Association guideline and the American College of Radiology Thyroid Imaging Reporting and Data System. Fine needle aspiration biopsy (FNAB) is the gold standard method in the evaluation of nodules with indication according to USG risk class. In the cytological evaluation of FNAB, the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) is the most frequently applied cytological classification. TBSRTC is a simplified, 6-category reporting system and was updated in 2023. The application of molecular tests to FNAB specimens, especially those diagnosed with Bethesda III and IV, is increasing to reduce the need for diagnostic surgery. Especially in Bethesda III and IV nodules, different methods are applied in the treatment of nodules according to the malignancy risk of each category, these are follow-up, surgical treatment, radioactive iodine treatment, and non-surgical ablation methods.

Performance of ACR TI-RADS and the Bethesda System in Predicting Risk of Malignancy in Thyroid Nodules at a Large Children's Hospital and a Comprehensive Review of the Pediatric Literature

While thyroid nodules are less common in children than in adults, they are more frequently malignant. However, pediatric data are scarce regarding the performance characteristics of imaging and cytopathology classification systems validated to predict the risk of malignancy (ROM) in adults and select those patients who require fine-needle aspiration (FNA) and possibly surgical resection. We retrospectively reviewed the electronic medical records of all patients 18 years of age or younger who underwent thyroid FNA at our institution from 1 July 2015 to 31 May 2022. Based on surgical follow-up from 74 of the 208 FNA cases, we determined the ROM for the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) ultrasound risk stratification system and The Bethesda System for Reporting Thyroid Cytopathology and added our results to those of pediatric cohorts from other institutions already published in the literature. We found the following ROMs for 1458 cases using ACR TI-RADS (TR): TR1. Benign: 2.2%, TR2. Not Suspicious: 9.3%, TR3. Mildly Suspicious: 16.6%, TR4. Moderately Suspicious: 27.0%, and TR5. Highly Suspicious 76.5%; and for 5911 cases using the Bethesda system: Bethesda I. Unsatisfactory: 16.8%, Bethesda II. Benign: 7.2%, Bethesda III: Atypia of Undetermined Significance: 29.6%, Bethesda IV. Follicular Neoplasm: 42.3%, Bethesda V. Suspicious for Malignancy: 90.8%, and Bethesda VI. Malignant: 98.8%. We conclude that ACR TI-RADS levels imply higher ROMs for the pediatric population than the corresponding suggested ROMs for adults, and, in order to avoid missing malignancies, we should consider modifying or altogether abandoning size cutoffs for recommending FNA in children and adolescents whose thyroid glands are smaller than those of adults. The Bethesda categories also imply higher ROMs for pediatric patients compared to adults.

Combined fine-needle aspiration with core needle biopsy for assessing thyroid nodules: a more valuable diagnostic method?

PURPOSE

This study aimed to evaluate the diagnostic value of combined fine-needle aspiration (FNA) with core needle biopsy (CNB) in thyroid nodules.

METHODS

FNA and CNB were performed simultaneously on 703 nodules. We compared the proportions of inconclusive results and the diagnostic performance for malignancy among FNA, CNB, and combined FNA/CNB for different nodule sizes.

RESULTS

Combined FNA/CNB showed lower proportions of inconclusive results than CNB for all nodules (2.8% vs. 5.7%, P<0.001), nodules ≤1.0 cm (4.9% vs. 7.3%, P=0.063), nodules >1.0 cm (2.0% vs. 5.0 %, P<0.001), nodules ≤1.5 cm (3.8% vs. 7.9 %, P<0.001), and nodules >1.5 cm (2.1% vs. 3.9 %, P=0.016). The sensitivity of combined FNA/CNB in predicting malignancy was significantly higher than that of CNB (89.0% vs. 80.0%, P<0.001) and FNA (89.0% vs. 58.1%, P<0.001) for all nodules. Within American College of Radiology Thyroid and Imaging Reporting and Data System grades 4-5, in the subgroup of nodules ≤1.5 cm, combined FNA/ CNB showed the best sensitivity in predicting malignancy (91.4%), significantly higher than that of CNB (81.0%, P<0.001) and FNA (57.8%, P<0.001). However, in the subgroup of nodules >1.5 cm, the difference between combined FNA/CNB and CNB was not significant (84.2% vs. 78.9%, P=0.500).

CONCLUSION

Regardless of nodule size, combined FNA/CNB tended to yield lower proportions of inconclusive results than CNB or FNA alone and exhibited higher performance in diagnosing malignancy. The combined FNA/CNB technique may be a more valuable diagnostic method for nodules ≤1.5 cm and nodules with a risk of malignancy than CNB and FNA alone.

FNA 2.0: Value of cytopathologist-performed ultrasound-guided core-needle biopsy

In the late 20^th century, pathologist-performed palpation-guided fine-needle aspiration (PG-FNA) of superficial masses was popularized in the United States. It brought pathologists out of the laboratory to see patients and the hope of decreasing the need for surgical biopsy for diagnostic purposes. This first iteration of minimally invasive tissue sampling could be informally called FNA 1.0. FNA 1.0 had shortcomings, such as detection of invasion in breast cancer, precise subtyping of lymphomas, aspiration of fibrous lesions, and diagnosis of sarcomas. The early 21^st century brought new hope. Ultrasound-guidance became commonly used to guide FNA of both palpable and non-palpable masses. Ultrasound-guided core-needle biopsy was available to complement FNA in select cases. Flow cytometry, immunohistochemistry, fluorescent in-situ hybridization, and genomic studies could be done on cell block and core biopsy specimens. These advances in minimally invasive tissue diagnosis could be informally called FNA 2.0. In particular, pathologist-performed ultrasound-guided core-needle biopsy can overcome many of the criticisms and shortcomings of FNA. As pathologists were once leaders in palpation-guided fine-needle aspiration, they now have the opportunity to add pathologist-performed ultrasound-guided core-needle biopsy to their skill set and emerge once again as leaders in minimally invasive tissue diagnosis. This will bring pathology to the next level.

Usefulness of ultrasound-guided core biopsy in thyroid nodules with inconclusive fine-needle aspiration biopsy findings

OBJECTIVES

To determine the diagnostic performance of ultrasound-guided core-needle biopsy in thyroid nodules after two inconclusive fine-needle aspiration biopsies. To assess the complications of core-needle biopsy. To analyze the reliability of diagnoses obtained with core-needle biopsy. To measure the economic impact of avoiding lobectomies in patients with benign core-needle biopsy findings.

MATERIAL AND METHODS

This retrospective study reviewed 195 core-needle biopsies in 178 patients. To determine the reliability of the core-needle biopsy findings, we compared the diagnosis from the core-needle specimen versus the histologic findings in the surgical specimens when core-needle biopsy findings indicated malignancy or follicular proliferation and versus the stability of the nodule on ultrasound follow-up for one year when core-biopsy findings indicated benignity.

RESULTS

Core-needle biopsy yielded a diagnosis for 179 (91.7%) nodules, of which 122 (62.5%) were classified as benign, 50 (25.6%) as follicular proliferation, and 7 (3.6%) as malignant. The findings were inconclusive for 16 (8.3%) nodules. Minor complications were observed in 4 (2%) patients; no major complications were observed. The sensitivity of core-needle biopsy for the diagnosis of thyroid cancer was low (42.8%) because the technique was unable to detect capsular or vascular invasion, although the specificity and positive predictive value (PPV) were 100%. However, when we considered histologic findings of malignancy and follicular proliferation positive because both require surgical resection, the sensitivity increased to 97.5% and the PPV decreased to 83.3%. There were 79 nodules with ultrasound follow-up for at least one year; 76 (96.2%) had negative core-needle biopsy findings, and 74 (97.3%) of these remained stable. The negative predictive value (NPV) for malignancy of the benign nodules was 98.6%, although no malignant transformation was observed. Nevertheless, the results of the statistical analysis do not allow us to recommend forgoing ultrasound follow-up in patients with benign core-biopsy findings. The cost savings of avoiding lobectomy in patients with benign nodules and stability of the nodule on ultrasound follow-up for at least one year was about 90%.

CONCLUSIONS

Core-needle biopsy of thyroid nodules is effective because it diagnoses more than 90% of nodules with inconclusive findings after fine-needle aspiration biopsy. It is safe if done by experienced professionals. It is reliable because it yields 100% specificity and 100% PPV for malignant nodule, 97.5% sensitivity for the detection of nodules that require surgery, and 98.6% NPV for benign nodules. It is efficient because it reduces the costs of diagnosis compared to lobectomy in benign nodules.

A Rare Case of Systemic Sarcoidosis in a Middle-Aged Female with a Solitary Thyroid Nodule

Sarcoidosis is a multisystem inflammatory disease characterized by the presence of noncaseating granulomas. Sarcoidosis can affect any organ of the body, the lung being the most affected. Sarcoidosis rarely affects the thyroid gland, and only a few cases of thyroid-related sarcoidosis have been reported in the literature. Herein, we report a case of systemic sarcoidosis with multiple organ involvement in a patient with a solitary left thyroid nodule and benign Fine Needle Aspiration (FNA) findings. The patient was eventually diagnosed with thyroid sarcoidosis using a core needle biopsy of the thyroid nodule. With this case report, we highlight the limitations of the FNA. This case report has the objective to encourage clinicians to include thyroid sarcoidosis in the differential diagnosis of thyroid nodules in patients with systemic sarcoidosis even with unremarkable FNA findings.

Thyroid diagnostic modalities (fine needle aspiration and core needle biopsy) with histology correlation: a tertiary centre experience

AIMS

To determine the proportion of thyroid fine needle aspiration (FNA) and core needle biopsy (CNB) cases reported at a single institute into each UK Royal College of Pathologists (RCPath) Thy1-5 and local T category, respectively. Where subsequent histology was available, malignancy rates, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were compared for both procedures.

METHODS

1591 FNAs (2010-2018) and 514 CNBs (2013-2018) cases were identified, together with paired histology excision specimens.

RESULTS

The FNA samples were classified as: Thy1: 45.3%, Thy2/Thy2c: 22.1%, Thy3a/Thy3f: 28%, Thy4: 1.6% and Thy5: 3%; while the CNB were classified as: T1: 7.2%, T2: 22.4%, T3 59.3%, T4: 1% and T5: 10.1%. Comparison of FNA and CNB classified as Thy5/T5 showed a 100% risk of malignancy (ROM), sensitivity (98% vs 100%), specificity (14.1% vs 12.1%), PPV (29.4% vs 29.4%), NPV (94.9% vs 100%) and accuracy (36.5% vs 35.6%), respectively, for a diagnosis of malignancy. ROMs for other categories were: Thy1/T1 (9% vs 6.7%), Thy2/T2 (5.1% vs 0%), Thy3/T3 (17.5% vs 18.4%) and Thy4/T4 (73.3% vs 100%).

CONCLUSIONS

The proportion of cases in each RCPath Thy category has remained relatively stable during the 9-year study period, with the exception of the Thy3a category, which has increased over time. This finding is in line with other more recent reports in the literature and the proportion of T3 cases in the CNB group. The proportion of Thy2/Thy2c cases has also reduced over time, reflecting a local change in the triaging protocol for probable benign lesions. Both FNA and CNB showed comparable performance in our study.

Diagnostic use of fine-needle aspiration cytology and core-needle biopsy in head and neck sarcomas

The diagnostic role of fine-needle aspiration cytology (FNAC) and core-needle biopsy (CNB) has not been comprehensively assessed in head and neck sarcomas. A systematic review of published cases (1990-2020) was conducted. Diagnostic performance of both FNAC/CNB to determine tumor dignity and histopathological diagnosis was calculated. One hundred and sixty-eight cases were included for which FNAC (n = 156), CNB (n = 8), or both (n = 4) were used. Predominant histologies were skeletal muscle, chondrogenic and vascular sarcomas. FNAC correctly assessed dignity in 76.3% and histology in 45% of cases. Dignity was significantly better for vascular tumors, metastatic and recurrent specimens, and worse for chondrogenic sarcomas. CNB showed a 92% accuracy to identify dignity and 83% for histopathology. FNAC and CNB are useful methods for the diagnosis of head and neck sarcomas, particularly well-suited in the context of recurrent or metastatic disease. The role of CNB remains largely unexplored for this indication.

Cytopathologic criteria and size should be considered in comparison of fine-needle aspiration vs. core-needle biopsy for thyroid nodules: results based on large surgical series

PURPOSE

To evaluate and compared the diagnostic performances of FNA and CNB using various cytopathologic criteria and size subgroups to see how the comparison results differ accordingly.

METHODS

From May 2012 to May 2019, 8187 thyroid nodules in 8139 patients who had undergone preoperative US-guided FNA or CNB at outside clinics were included in this retrospective study (mean size: 11.9 ± 9.5 mm). Preoperative US-FNA was performed in 7496 (91.6%) nodules and US-CNB was performed in 691 (8.4%) nodules. Propensity score matching was used to compare the sensitivities between FNA and CNB in diagnosis of malignancy and neoplasm according to different cytologic test criteria.

RESULTS

Of the 8187 thyroid nodules, 7833 (95.7%) were malignant and 354 (4.3%) were benign. Mean size of the thyroid nodules in the CNB group was significantly larger than the FNA group, 15.7 ± 12.7 mm vs. 11.6 ± 9.0 mm, respectively (P < 0.001). After matching, sensitivity in the CNB group were significantly higher in the total population, and in subgroups <10 mm for criteria 1 and 2 (all P < 0.05, respectively). No significant differences were seen between the sensitivities of FNA and CNB for nodules ≥10 mm regardless of criteria in diagnosis of malignancy or neoplasm (all P > 0.05, respectively).

CONCLUSIONS

Results comparing sensitivities between FNA and CNB differ according to the different cytopathologic criteria used for calculation. CNB has significantly higher sensitivity to FNA in subcentimeter nodules when using criteria 1 or 2. Diagnostic sensitivities did not show significant differences for nodules ≥10 mm regardless of the cytopathologic criteria used, that should be considered in selecting biopsy methods.

Usefulness of ultrasound-guided core biopsy in thyroid nodules with inconclusive fine-needle aspiration biopsy findings

OBJECTIVES

To determine the diagnostic performance of ultrasound-guided core-needle biopsy in thyroid nodules after two inconclusive fine-needle aspiration biopsies. To assess the complications of core-needle biopsy. To analyze the reliability of diagnoses obtained with core-needle biopsy. To measure the economic impact of avoiding lobectomies in patients with benign core-needle biopsy findings.

MATERIAL AND METHODS

This retrospective study reviewed 195 core-needle biopsies in 178 patients. To determine the reliability of the core-needle biopsy findings, we compared the diagnosis from the core-needle specimen versus the histologic findings in the surgical specimens when core-needle biopsy findings indicated malignancy or follicular proliferation and versus the stability of the nodule on ultrasound follow-up for one year when core-biopsy findings indicated benignity.

RESULTS

Core-needle biopsy yielded a diagnosis for 179 (91.7%) nodules, of which 122 (62.5%) were classified as benign, 50 (25.6%) as follicular proliferation, and 7 (3.6%) as malignant. The findings were inconclusive for 16 (8.3%) nodules. Minor complications were observed in 4 (2%) patients; no major complications were observed. The sensitivity of core-needle biopsy for the diagnosis of thyroid cancer was low (42.8%) because the technique was unable to detect capsular or vascular invasion, although the specificity and positive predictive value (PPV) were 100%. However, when we considered histologic findings of malignancy and follicular proliferation positive because both require surgical resection, the sensitivity increased to 97.5% and the PPV decreased to 83.3%. There were 79 nodules with ultrasound follow-up for at least one year; 76 (96.2%) had negative core-needle biopsy findings, and 74 (97.3%) of these remained stable. The negative predictive value (NPV) for malignancy of the benign nodules was 98.6%, although no malignant transformation was observed. Nevertheless, the results of the statistical analysis do not allow us to recommend forgoing ultrasound follow-up in patients with benign core-biopsy findings. The cost savings of avoiding lobectomy in patients with benign nodules and stability of the nodule on ultrasound follow-up for at least one year was about 90%.

CONCLUSIONS

Core-needle biopsy of thyroid nodules is effective because it diagnoses more than 90% of nodules with inconclusive findings after fine-needle aspiration biopsy. It is safe if done by experienced professionals. It is reliable because it yields 100% specificity and 100% PPV for malignant nodule, 97.5% sensitivity for the detection of nodules that require surgery, and 98.6% NPV for benign nodules. It is efficient because it reduces the costs of diagnosis compared to lobectomy in benign nodules.

Usage and Diagnostic Yield of Fine-Needle Aspiration Cytology and Core Needle Biopsy in Thyroid Nodules: A Systematic Review and Meta-Analysis of Literature Published by Korean Authors

Objectives

The usefulness of core needle biopsy (CNB) for the diagnosis of thyroid nodules remains controversial, and preferences vary across hospitals. The purpose of this study was to assess the actual use of CNB in Korea and to analyze the advantages and disadvantages of CNB through a systematic review and meta-analysis of papers published by Korean authors.

Methods

A meta-analysis of full-text publications published in English presenting data from Korea retrieved from the Embase literature database was performed.

Results

CNB led to a significantly lower proportion of non-diagnostic results than fine-needle aspiration (FNA). However, the frequency of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) did not decrease as a result of performing CNB in nodules with initial AUS/FLUS results, while it increased in consecutive cases. A subcategory analysis of AUS/FLUS showed that the increased frequency of AUS/FLUS findings on CNB was due to more frequent diagnoses of architectural atypia and follicular neoplasm, which resulted in a higher frequency of inconclusive findings in consecutive cases compared to FNA. Hospitals favoring CNB had a higher proportion of AUS/FLUS diagnoses. Although the complication rate did not differ significantly between CNB and FNA, serious complications of CNB did occur.

Conclusion

A reduced frequency of non-diagnostic results may be a definite advantage of CNB over FNA. However, the increased frequency of diagnoses of architectural atypia and follicular neoplasm should be considered when selecting CNB as a diagnostic tool.

Is thyroid core needle biopsy a valid compliment to fine-needle aspiration?

Fine-needle aspiration (FNA) has long been considered the first and an important diagnostic tool in the evaluation of thyroid nodules. The advantages of FNA include simplicity, safety, cost-effectiveness, high diagnostic accuracy, and low complication rate. Nevertheless, limitations associated with FNA include a substantial rate of inconclusive results and indeterminate interpretations. Therefore, core needle biopsy (CNB) of the thyroid gland has been proposed as a complementary or even alternate diagnostic method to evaluate thyroid nodules. Although controversial, a growing number of researchers have reported CNB to be an effective and safe sampling method for thyroid nodules, especially for cases with inadequate or indeterminate FNA yields. Skeptics highlight local pain and bleeding risk. Supporters highlight the potential likelihood of overcoming FNA limitations by obtaining a larger amount of tissue and using architecture and cellular details to guide possible ancillary testing. This review evaluates the indications, advantages, and disadvantages of CNB as compared with FNA of the thyroid gland.

Core-Needle Biopsy Does Not Show Superior Diagnostic Performance to Fine-Needle Aspiration for Diagnosing Thyroid Nodules

PURPOSE

To compare the diagnostic performances of fine-needle aspiration (FNA) and core-needle biopsy (CNB) for thyroid nodules according to nodule size.

MATERIALS AND METHODS

This retrospective study included 320 thyroid nodules from 320 patients who underwent both FNA and CNB at outside clinics and proceeded with surgery in our institution between July 2012 and May 2019. According to nodule size, the diagnostic performances of FNA and CNB were calculated using various combinations of test-negatives and test-positives defined by the Bethesda categories and were compared using the generalized estimated equation and the Delong method.

RESULTS

There were 279 malignant nodules in 279 patients and 41 benign nodules in 41 patients. The diagnostic performance of FNA was mostly not different from CNB regardless of nodule size, except for negative predictive value, which was better for FNA than CNB when applying Criteria 1 and 2. When applying Criteria 3, the specificity and positive predictive value of FNA were superior to CNB regardless of size. When applying Criteria 4, diagnostic performance did not differ between FNA and CNB regardless of size. After applying Criteria 5, diagnostic performance did not differ between FNA and CNB in nodules ≥2 cm. However, in nodules ≥1 cm and all nodules, the sensitivity, accuracy, and negative predictive value of CNB were better than those of FNA.

CONCLUSION

CNB did not show superior diagnostic performance to FNA for diagnosing thyroid nodules.

Evaluation of surgical risk and prognosis between thyroid nodules of size <1 and ≥1 cm

Background

The objective of this study was to evaluate the surgical risk and prognosis between thyroid nodules of size <1 and ≥1 cm and to explore whether it is reasonable generally to ignore the diagnosis and treatment of thyroid nodules and thyroid carcinoma <1 cm in wide areas of China.

Methods

A retrospective observational study included all first-time thyroid surgery patients between January 2005 and December 2016 of the First Affiliated Hospital of Harbin Medical University. All patients were divided into two groups (group A: <1 cm, group B: ≥1 cm) according to the maximum diameter of the nodules and demographics, surgery procedure, pathology, postoperative complications, morbidity, and mortality were analyzed.

Results

A total of 6,317 patients were reviewed and 3,424 (54.20%) of them were malignant; 2,128 patients in group A and 4,189 in group B. Patients in group A had better pathological diagnosis, inferior extent of lymph node metastasis, less surgical complexity, fewer postoperative complications, and longer disease-free survival (DFS).

Conclusions

Thyroid operations were safer and involved fewer postoperative complications when thyroid nodules were <1 cm and patients who were diagnosed with malignant thyroid disease had superior prognoses. Underdeveloped regions of China should diagnose and treat thyroid nodules <1 cm early.

TIRADS score is of limited clinical value for risk stratification of indeterminate cytological results

CONTEXT

Thyroid nodules with cytological indeterminate results represent a daily and recurrent issue for patient management.

OBJECTIVE

The primary aim of our study was to determine if TIRADS (Thyroid Imaging Reporting and Data System) could be used to stratify the malignancy risk of these nodules and to help in their clinical management. Secondary objective was to estimate if this risk stratification would change after reclassification of encapsulated non-invasive follicular variant of papillary carcinomas (FVPTC) as non-invasive follicular thyroid neoplasm (NIFTP).

PATIENTS AND METHODS

Single-center retrospective study of a cohort of 602 patients who were referred for ultrasound-guided fine-needle aspiration from January 2010 to December 2016 with an indeterminate cytological result and in whom histological results after surgery were available. TIRADS score was prospectively determined for all patients included. Nodules that had been classified as FVPTC were submitted to a rereading of histological report and reclassified as NIFTP when judged relevant. A table of malignancy risk crossing Bethesda and TIRADS results was built before and after this reclassification.

RESULTS

The study included 602 cytologically indeterminate nodules. TIRADS score was positively correlated with the malignancy rate (P < 0.0001). Risk stratification with TIRADS was significant only in Bethesda V nodules (P = 0.0004). However, the risk of malignancy in this Bethesda V category was always above 45%, whatever the TIRADS score.

CONCLUSION

For a clinician facing an indeterminate cytological result for a thyroid nodule, return to TIRADS score is of limited value in most conditions to rule in or rule out malignancy and to guide subsequent management of patients.

The role of core needle biopsy in the diagnosis of initially detected thyroid nodules: a systematic review and meta-analysis

OBJECTIVES

To systematically review the published literature and evaluate the efficacy and safety of core needle biopsy (CNB) for initially detected thyroid nodules.

METHODS

The Ovid-MEDLINE and Embase databases were searched for studies evaluating CNB for the diagnosis of initially detected thyroid nodules. A meta-analysis was performed to evaluate non-diagnostic results, inconclusive results and diagnostic accuracy for a diagnosis of malignancy with CNB. To overcome heterogeneity, multiple subgroup analyses were performed. The complication rate was also evaluated.

RESULTS

Thirteen eligible studies, which included a total sample size of 9,166 patients with 13,585 nodules, were included. The pooled proportions were 3.5% (95% CI 2.4-5.1) for non-diagnostic results and 13.8% (95% CI 9.1-20.3) for inconclusive results. Considerable heterogeneity was observed among the studies in terms of the pooled proportions for CNB (I²=92.9%, 97%). With regard to the diagnostic performance for malignancy, the sensitivity was 80% (95% CI 75-85) and the specificity was 100% (95% CI 93-100). Only two major complications of CNB were observed.

CONCLUSIONS

CNB demonstrates a low non-diagnostic result rate and high diagnostic accuracy for initially detected thyroid nodules and a low major complication rate. These findings indicate that CNB may be a feasible diagnostic tool for patients with initially detected thyroid nodules.

KEY POINTS

CNB demonstrates high diagnostic accuracy for initially detected thyroid nodules. CNB demonstrates a low major complication rate. CNB may be a feasible diagnostic tool for patients with initially detected thyroid nodules.

Reliability of core needle biopsy as a second-line procedure in thyroid nodules with an indeterminate fine-needle aspiration report: a systematic review and meta-analysis

PURPOSE

This study was undertaken to summarize the published data and to provide more robust estimates regarding the issue of core needle biopsy (CNB) for discriminating thyroid nodules with indeterminate fine-needle aspiration (FNA) results.

METHODS

The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The sources comprised studies published through November 2017. Original articles that investigated CNB in indeterminate thyroid lesions were searched. A random-effects model was used for statistical pooling of the data. The I² index was used to quantify the heterogeneity among the studies. The Egger test was carried out to evaluate the possible presence of significant publication bias. Quality assessment of the studies was performed according to QUADAS-2.

RESULTS

A total of 205 articles were retrieved, seven were initially selected, and the data of five papers were ultimately pooled in a meta-analysis. The overall cancer rate was 34%. The rate of cancers correctly diagnosed by CNB was 83% (95% confidence interval [CI], 76 to 89), with neither heterogeneity (I²=25%) nor publication bias (Egger test, P=0.918). The rate of benign nodules correctly assessed by CNB was 84% (95% CI, 65 to 97), with significant heterogeneity (I²=93.4%) and publication bias (Egger test, P=0.016).

CONCLUSION

Evidence was found that CNB can correctly diagnose the majority of nodules previously read as indeterminate on FNA.