Risk of Malignancy in Thyroid Nodules 4 cm or Larger

Correlation between ultrasonographic and cytologic features of thyroid nodules: a single-center cross-sectional study

A thyroid nodule is managed according to the clinical context, ultrasound (US) findings, and fine needle aspiration (FNA) results. Most thyroid nodules are benign; however, nodule classification is crucial to avoid unnecessary thyroid surgery. We conducted this study to compare the findings of fine-needle aspiration cytology (FNAC) expressed using the Bethesda system with the features of thyroid US classified using the EU-TIRADS classification to assess the risk of malignancy. A descriptive and analytical study involving 99 patients with thyroid nodules followed up in the Department of Endocrinology-Diabetology and Nutrition. Data were collected from medical records and analyzed using SPSS software V21. FNA was performed on 121 nodules using the BETHESDA system. These nodules were classified as malignant, suspicious for follicular neoplasm, and suspicious for malignancy in 5.8%, 5%, and 1.7% of cases, respectively. As for the EU-TIRADS 2017 classification, 59.5% of benign nodules were classified as EU-TIRADS III, whereas 66.7% of malignant nodules were classified as EU-TIRADS V and significantly related to malignant prediction (P = 0.000). The size of nodules was significantly correlated to the risk of malignancy (P = 0.013). Seventy-five percent of nodules with central vascularity were malignant (P = 0.012). Irregularity of nodule contours was significantly associated with the risk of malignancy, as 30% of nodules with irregular contours were Bethesda VI (P = 0.003). Hypoechogenicity was found in 77.8% of malignant nodules (P = 0.004). Additionally, only 9.2% of the nodules were taller than wide, of which 37.5% were malignant (P = 0.012). For a safe management strategy, US-guided FNAC should be performed on each suspicious thyroid nodule, given the correlation between EU-TIRADS classification features and the risk of malignancy.

The Utility of ACR TI-RADS in Predicting False-Negative Fine Needle Aspiration for Thyroid Cancer

BACKGROUND

Thyroid nodule fine needle aspiration (FNA) biopsies are associated with a low false-negative rate. There is limited data regarding the predictive value of American College of Radiology Thyroid Imaging Reporting and Data System for false-negative FNA.

METHODS

This single-center retrospective study evaluated 119 patients who underwent thyroidectomy. The association of TR category, along with other clinical variables, with false-negative FNA was evaluated.

RESULTS

The overall false-negative rate of FNA was 10.8% (n = 9). False-negative FNAs were associated with younger age (mean 42 years vs 50.6 years, P = .04), larger nodule size (mean 4.4 cm vs 3.2 cm, P = .03), and a lower TR category (median 3 v 4, P = .01).

DISCUSSION

Lower TR category, younger age, and larger nodule size were associated with false-negative FNA of thyroid nodules. These findings should be taken into context when counseling patients with thyroid nodules who have a benign FNA.

Concordance of the ACR TI-RADS Classification With Bethesda Scoring and Histopathology Risk Stratification of Thyroid Nodules

Importance

Although most thyroid nodules are benign, 10% to 15% of them harbor cancer. Thyroid ultrasonography is useful for risk stratification of nodules, and American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) classification provides recommendations for fine-needle aspiration cytology (FNAC) based on objective ultrasonographic features of these nodules.

Objective

To validate the concordance of ACR TI-RADS classification with Bethesda classification and histopathology.

Design, Setting, and Participants

This retrospective cohort study was performed to evaluate the concordance of ACR TI-RADS classification with Bethesda classification and histopathology and was conducted in Singapore General Hospital Outpatient Otolaryngology clinic in March 2021 to May 2021. Data analysis was performed in May 2021.

Main Outcomes and Measures

Results were deemed concordant when ACR TI-RADS recommendations aligned with Bethesda scores. Conversely, results were classified as nonconcordant with Bethesda scores and/or histopathology results when nodules that were recommended for FNAC yielded benign results or nodules that were not recommended for FNAC yielded malignant results.

Results

A total of 446 patients (370 women [83%]; mean [range] age, 60 [24-89] years) who underwent ultrasonography of the thyroid and ultrasonography-guided thyroid FNACs were identified. A total of 492 of 630 nodules (78.1%) were benign on FNAC (Bethesda II). Score 3 ACR TI-RADS nodules yielded the highest negative predictive values: 94.6% (95% CI, 92.9%-95.9%; P < .001) compared with Bethesda scoring and 100.0% (95% CI, 15.8%-100.0%; P = .003) compared with histopathology. Score 4 or 5 ACR TI-RADS nodules yielded positive predictive values of 2.8% and 16.2%, respectively, compared with Bethesda scoring and 6.1% and 66.7%, respectively, compared with histopathology. Small (<1.5 cm) ACR TI-RADS nodules of scores of 4 and 5 that were not recommended for FNAC yielded a malignant risk of 5.7% and 25.0% on Bethesda 5 and 6, respectively. On surgical excision, 5 of 46 (10.9%) ACR TI-RADS 4 nodules and 15 of 21 (71.4%) of ACR TI-RADS 5 nodules were confirmed to be malignant. Among nodules initially not recommended for FNAC, histopathology-proven cancer was found in 4 of 13 (30.7%) and 3 of 6 (50.0%) of nodules, respectively.

Conclusions and Relevance

These findings suggest that ACR TI-RADS score 3 nodules have a low risk of cancer and should be considered for FNAC only if nodules are 2.5 cm or larger. Patients with small (<1.5 cm) ACR TI-RADS 4 and 5 nodules should be appropriately counseled for FNAC to exclude cancer.

Comparative analysis of accuracy between fine-needle aspiration biopsy and postoperative histopathology for detecting large thyroid nodules: A retrospective observational study

To avoid unnecessary surgeries, ultrasound-guided fine-needle aspiration biopsy (FNAB) is an effective and reliable procedure for the preoperative evaluation of thyroid nodules. However, there have been only a limited number of studies exploring the ability of preoperative FNAB to distinguish malignancy compared to postoperative histopathology in thyroid nodules larger than 4 cm. The aim of this study was to investigate the diagnostic accuracy of FNAB compared to postoperative histopathology in distinguishing malignancy in thyroid nodules larger than 4 cm. A single-center retrospective observational study was conducted at Dr. Zainoel Abidin Hospital, Banda Aceh, Indonesia, between January 2014 and December 2018. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were calculated. A total of 83 patients were included in the study. The results showed that preoperative FNAB may have the ability to distinguish malignancy compared to postoperative histopathology. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 42.85%, 98.38%, 90.00%, 83.56%, and 84.33%, respectively. These data suggested that ultrasound-guided preoperative FNAB is a reliable diagnostic tool in the preoperative evaluation of thyroid nodules larger than 4 cm, but it has limited capability in distinguishing malignancies. In conclusion, although FNAB may be useful in reducing unnecessary surgeries, histopathology remains the preferred method for confirming malignancy in thyroid nodules.

Risk of malignancy and diagnostic accuracy of fine-needle aspiration biopsy in thyroid nodules with diameters greater than 4 centimeters

Objective

The risk of malignancy and diagnostic accuracy of fine-needle aspiration biopsy (FNAB) of thyroid nodules (TN) with diameters ≥ 3-4 cm remains controversial. However, some groups have indicated surgical treatment in these patients regardless of the FNAB results. We aimed to evaluate the diagnostic accuracy of the FNAB in systematically resected ≥4 cm TN and if the risk of malignancy is higher in these patients.

Subjects and methods

We retrospectively evaluated 138 patients (142 nodules) with TN with diameters ≥4 cm who underwent thyroidectomy.

Results

The FNAB results were nondiagnostic/unsatisfactory (ND/UNS) in 2.1% of the cases and benign in 51.4%. They indicated atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) in 23.9% of cases, follicular neoplasia/suspicious for a follicular neoplasm (FN/SFN) in 9.2%, suspicion of malignancy (SUS) in 8.5%, and malignant in 4.9%. The histopathological analysis after thyroidectomy revealed a thyroid cancer rate of 100% in the FNABs classified as malignant, 33.3% in SUS cases, 7.7% in FN/SFN, 17.6% in AUS/FLUS, and 4.1% in benign FNABs. None of the ND/UNS FNABs were malignant. The global malignancy diagnosis was 14.8% (n = 21). However, the rate of false negatives for FNAB was low (4.1%).

Conclusion

We showed that the risk of malignancy in nodules with diameters ≥4 cm was higher compared to the risk of thyroid cancer in TN in general. However, we found a low rate of false-negative cytological results; therefore, our data do not justify the orientation of routine resection for these larger nodules.

Accuracy of fine-needle aspiration cytopathology to differentiate malignant and benign thyroid nodules with ≥4 cm diameter: A retrospective study

BACKGROUND

Thyroid nodules (TN) are commonly present in the general population and are usually pathologically benign. An initial diagnosis with fine-needle aspiration (FNA) cytopathology could help clinical decision-making with fewer complications. As the previous studies suggest surgical procedures for >4 cm TNs, we aimed to investigate the accuracy of preoperative FNA cytology to predict malignancy risk in these nodules in a sample of the Iranian population.

METHODS

Patients with ≥4 cm TNs who had preoperative FNA cytology, underwent nodulectomy and had a histopathological report were included. Each patient's preoperative demographic, ultrasonographic, and cytology data were gathered. After surgery, resected samples were assessed pathologically and diagnosed as benign or malignant. Finally, data were analyzed to evaluate the presurgical accuracy of the FNA cytology.

RESULTS

We identified 41 (51.25%) patients with malignant legions among our study population (N = 80). The pathology reports were indeterminate in 3 patients with follicular neoplasm. Bethesda scores were substantially higher in patients with malignancy. The sensitivity, specificity, and false-negative rate of FNA cytology reports using the Bethesda system were 73.7%, 74.2%, and 26.3%, respectively. There was no association between malignancy and TNs' size, neither their volume nor their highest diameter.

CONCLUSION

FNA cytology is not as sensitive and specific in nodules>4 cm as in smaller ones. However, it can still be used alongside other diagnostic procedures in malignancy screening. Clinicians should make more complex decisions considering various influential factors to avoid missing malignant lesions and reduce diverse probable complications of highly invasive diagnostic surgery. Further prospective research on >4 cm TNs and their multiple features' association with malignancy is required for more precise judgment.

Clinicopathologic features of thyroid nodules with PTEN mutations on preoperative testing

The incidence of cancer in thyroid nodules carrying germline or somatic phosphatase and tensin homolog (PTEN) mutations is not well-defined. This study characterizes the clinical and histopathologic features of thyroid nodules with preoperatively detected PTEN mutations and their impact on management. Thyroid nodules with PTEN mutations on molecular testing of fine-needle aspiration (FNA) specimens from November 2017 to July 2020 at our institution were included. Demographic and clinicopathologic data were obtained through retrospective chart review. We identified 49 PTEN mutation-positive nodules from 48 patients. Surveillance was pursued for 28 patients and surgery for 20 patients. There were 14 follicular adenomas (FA), 4 oncocytic adenomas, 1 oncocytic hyperplastic nodule, and 1 encapsulated follicular variant papillary thyroid carcinoma (EFVPTC). The EFVPTC had two somatic PTEN mutations, an NRAS mutation, and was a low-risk tumor with capsular but no angiolymphatic invasion. Four patients, all with multiple nodules, had PTEN hamartoma syndrome (PHTS) with germline mutations or a clinical diagnosis of Cowden syndrome (CS); two had surgery finding FAs, and one previously had follicular carcinoma removed. Among surveillance patients, 1/20 had a significant increase in the size of the thyroid nodule and underwent repeat FNA, and no thyroid malignancy was found with a mean of 1.77 years of follow-up (range 1.00-2.78). Thyroid nodules with isolated somatic PTEN mutations are primarily benign and unlikely to grow at a high rate, at least on short-term follow-up. About 8% of patients with PTEN mutations may have PHTS or CS, which should be suspected in younger patients with multiple thyroid nodules.

Navigating the Debate on Managing Large (≥4 cm) Thyroid Nodules

PURPOSE

Discordant practice guidelines for managing large thyroid nodules may result in unnecessary surgeries and costs. Recent data suggest similar false-negative rates in fine needle aspiration (FNA) biopsies between small (<4 cm) and large (≥4 cm) nodules, indicating that monitoring rather than surgery may be appropriate for large biopsy-negative nodules. We investigated the management of thyroid nodules ≥4 cm to determine the proportion of surgeries not necessary for diagnostic purposes and examined for potential predictors.

METHODS

This was a retrospective cohort study of patients who received a FNA of nodule(s) ≥4 cm between 11/1/2014 and 10/31/2019 at the University of Vermont Medical Center. A surgery was considered unnecessary if the FNA result was benign in the absence of any of the following: compressive symptoms, family history of thyroid cancer in a first degree relative, history of neck irradiation, toxic nodule or toxic multinodular goiter, or substernal extension. Data were analyzed with Wilcoxon rank sum tests, chi square, or Fisher's exact tests.

RESULTS

177 patients had a ≥4 cm nodule during the timeframe and half (54.2%) had surgery. Patients who underwent surgery were significantly younger (51.5 years vs. 62 years; P < 0.001), more likely to report obstructive symptoms (34.4% vs. 12.1%; P < 0.001) and had a larger nodule size (5.0 cm vs. 4.7 cm; P=0.26). Forty-one patients with benign (Bethesda II) FNA results had surgery, all with negative surgical pathology. Thirteen percentage (23/177) of surgeries were potentially not necessary for diagnostic purposes.

CONCLUSION

Approximately half of our patients with ≥4 cm nodules had surgery, with 13% having surgery not necessary for diagnostic purposes revealing opportunities for improving care and costs.

Predictive Value of a Genomic Classifier in Indeterminate Thyroid Nodules Based on Nodule Size

Importance

Genomic classifiers were developed to better guide clinicians in the treatment of indeterminate thyroid nodules (ITNs). To our knowledge, whether there is variation in the diagnostic accuracy of these tests depending on ITN size has not been previously studied.

Objective

To analyze the diagnostic performance of a genomic classifier in relation to ITN size.

Design, Setting, and Participants

A case series study with medical records review was conducted including all patients with a cytologic diagnosis of ITN managed with genomic classifier testing and surgery from January 2015 to December 2018 at NYU Langone Health. Demographics, ITN characteristics, genomic profiles, treatment, and final pathologic findings were recorded. Data analysis was conducted from March to April 2021.

Main Outcomes and Measures

The primary aim was to assess the positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of a genomic classifier test (ThyroSeq) in relation to ITN size (<2, 2-4, and >4 cm). The secondary aim was to investigate the risk of cancer associated with genetic signatures.

Results

Of the 212 patients with 218 ITNs, 158 (74.5%) were women; median (SD) age was 49 (15.6) years. Genomic classifier results were positive in 173 ITNs (79.4%) treated with surgery. In this group of 173 positive ITNs, 46 (26.6%) were malignant on final pathologic testing. Overall, the observed cancer prevalence in the population was 23.9% (52 ITNs). In 45 ITNs that underwent surgery despite a negative genomic classifier interpretation, 6 (13.3%) were malignant. The PPV of a positive test was 27% and the NPV was 87%. The PPV and NPV findings improved as the ITN size increased (<2 cm [n = 98]: PPV, 25%; NPV, 79% vs >4 cm [n = 33]: PPV, 50%; NPV, 89%). Test specificity was higher in larger ITNs (<2 cm: 15% vs >4 cm: 40%; P = .01). Isolated RAS sequence variations were the most common variant identified in malignant nodules (11 [21.1%] of all ITNs), followed by BRAF variants (7 [13.5%] of all ITNs).

Conclusions and Relevance

In this case series, the performance of the ThyroSeq test improved for larger ITNs. The risk of cancer in large ITNs with negative test results was low. These data suggest that, in genomic classifier-negative ITNs larger than 4 cm, initial management of thyroid lobectomy may be sufficient.

Thyroid Nodule Size and Prediction of Cancer: A Study at Tertiary Care Hospital in Saudi Arabia

Background

Thyroid noduleshave become relatively common in clinical practice,and their prevalence increases with age. The majority of thyroid nodules are benign, with 5-15% being malignant. There are a number of well-established predictors of malignancy in thyroid nodules, but thyroid nodule size has been a cause for concern for many researchers and results of the studies are still controversial about their probability of malignancy. Up to the current knowledge, there is no published study that evaluates if thyroid nodule size is associated with the risk of malignancy in Saudi Arabia, so in this study, we aim to find that.

Methods

This is a retrospective study of 987 patients who underwent thyroid nodule fine-needle aspiration (FNA) and subsequent thyroidectomy for thyroid nodules measuring ≥ 1 cm.

Results

Thyroid cancer was more prevalent in males than females, and in patients who were older than or equal to 45 years. Nodular size of 1 - 1.9 cm was more prevalent among cancer patients than in benign cases (p<0.001).

Conclusions

The highest malignancy risk was observed in nodules <2 cm and no increase in malignancy risk for nodules >2 cm. Nevertheless, when examined by type of thyroid malignancy, the rate of follicular carcinoma and other rare malignancy increased with increasing nodule size.

Clinical and Ultrasound Thyroid Nodule Characteristics and Their Association with Cytological and Histopathological Outcomes: A Retrospective Multicenter Study in High-Resolution Thyroid Nodule Clinics

INTRODUCTION

Thyroid nodules are a common finding. A high-resolution thyroid nodule clinic (HR-TNC) condenses all tests required for the evaluation of thyroid nodules into a single appointment. We aimed to evaluate the clinical outcomes at HR-TNCs.

DESIGN AND METHODS

A retrospective cross-sectional multicenter study including data from four HR-TNCs in Spain. We evaluated fine-needle aspiration (FNA) indications and the association between clinical and ultrasound characteristics with cytological and histopathological outcomes.

RESULTS

A total of 2809 thyroid nodules were included; FNA was performed in 82.1%. Thyroid nodules that underwent FNA were more likely larger, isoechoic, with microcalcifications, and in younger subjects. The rate of nondiagnostic FNA was 4.3%. A solid component, irregular margins or microcalcifications, significantly increased the odds of Bethesda IV-V-VI (vs. Bethesda II). Irregular margins and a solid component were independently associated with increased odds of malignancy. Thyroid nodules <20 mm and ≥20-<40 mm had a 6.5-fold and 3.3-fold increased risk for malignancy respectively in comparison with those ≥40 mm.

CONCLUSION

In this large multicenter study, we found that the presence of a solid component and irregular margins are factors independently related to malignancy in thyroid nodules. Since nodule size ≥40 mm was associated with the lowest odds of malignancy, this cut-off should not be a factor leading to indicate thyroid surgery. HR-TNCs were associated with a low rate of nondiagnostic FNA.

Thyroid nodules over 4 cm do not have higher malignancy or benign cytology false-negative rates

PURPOSE

Whether thyroid nodules 4 cm or larger with benign cytology carry a higher risk of malignancy, and should be managed differently than smaller nodules remains controversial. We aimed to evaluate the malignancy rate and benign cytology false-negative rate in thyroid nodules ≥4 cm compared with those <4 cm.

METHODS

All thyroidectomies between January 2010 and December 2014 were reviewed. Patient demographics, preoperative sonographic nodule size, fine needle aspiration cytology (FNAC), and final surgical pathology results were compared for index nodules ≥4 vs. <4 cm.

RESULTS

A total of 490 index nodules with preoperative FNAC were identified. A total of 137 nodules were ≥4 cm and 353 nodules were <4 cm. The prevalence of carcinoma was lower (23 vs. 53%) in nodules ≥4 vs. <4 cm (p < 0.0001). The false-negative rate of benign FNAC for ≥4 and <4 cm index nodule was 5.2% and 5.9%, respectively (p = 1.000).

CONCLUSIONS

This study shows that thyroid nodules ≥4 cm do not have a higher malignancy rate at surgery nor higher benign cytology false-negative rate than smaller nodules. Thyroid nodules over 4 cm do not require resection, to rule out malignancy, based on size alone.

The influence of thyroid nodule size on the diagnostic efficacy and accuracy of ultrasound guided fine-needle aspiration cytology

BACKGROUND

Diagnostic accuracy of fine-needle aspiration cytology (FNAC) in large and subcentimeter nodules is still debated. We aimed to evaluate the impact of nodule size on efficacy of the ultrasound-guided FNAC.

METHODS

B-mode grayscale ultrasound (US), US-guided FNAC according to Bethesda system and histopathological data of 514 nodules from 371 patients, who underwent thyroidectomy were examined retrospectively. Nodules were grouped by maximal diameter; group A nodules were smaller than 10 mm (n = 59), group B nodules were between 10 and 29 mm (n = 218), and group C nodules were 30 mm or greater (n = 130).

RESULTS

Sensitivity, specificity, and accuracy of FNAC was 92.0%, 100%, and 95.1% in group A, 80.7%, 99.1%, and %92.9 in group B, 70.0%, 98.9%, and 95.8% in group C nodules, respectively. The prevalence of papillary thyroid cancer (PTC) and incidental PTC were 44.2% (n = 164) and 6.4% (n = 24), respectively. Malignancy rate was more frequent in group A when compared to groups B and C (P < 0.01). Nodule size was positively associated with follicular cancer risk (P = 0.009). The thyroid stimulating hormone level was positively associated with malignancy (P = 0.02) and optimal cut-off value was 0.96 mIU/L. False-negative rate was 8.0%, 19.3%, and 30.0% in groups A, B, and C nodules, respectively.

CONCLUSIONS

Although the malignancy rate was low in nodules ≥30 mm, diagnostic surgery for large nodules should be considered because of decreased reliability of FNAC, ineffectiveness of clinical and sonographic criteria. False-negative rate was relatively low and malignancy rate was high in subcentimeter nodules, supporting the accuracy of FNAC.

Malignancy risk for thyroid nodules larger than 4 cm and diagnostic reliability of ultrasound-guided FNAB results

Objectives

Our aim in the present study was to investigate the relation between thyroid nodule diameter and malignancy, and the diagnostic accuracy of fine needle aspiration biopsy (FNAB) for thyroid nodules larger than 4 cm.

Material and Methods

Preoperative patient demographics such as age and gender, thyroid nodule diameter, FNAB results and postoperative pathology results were recorded. The relation between age, gender, thyroid nodule size of the patients and malignancy was examined. Also, the sensitivity, specificity, false negativity, false positivity and accuracy rates of FNBA of the patients whose thyroid nodule size was lower than 4 cm and the ones whose thyroid nodule size was higher than 4 cm were analyzed.

Results

There was no significant difference between males and females in terms of malignancy rate (p= 0.15). There was no significant relation between malignancy and patient age (p= 0.92). No significant difference was found between the group with thyroid nodule diameter of > 4 cm and the group thyroid with nodule diameter of <4 cm in terms of malignancy (p= 0.91). In the group with thyroid nodule diameter of > 4 cm, sensitivity, specificity, false negativity, false positivity, and accuracy rates of FNAB were 15%, 100%, 84%, 0%, and 70%, respectively. In the group with thyroid nodule diameter of <4 cm, sensitivity, specificity, false negativity, false positivity, and accuracy rates of FNAB were 53%, 100%, 46%, 0% and 80%, respectively.

Conclusion

Our study put forward that thyroid nodule diameter is not the only predictor parameter whilst predicting malignancy. However, it was observed that FNAB sensitivity and false negativity were higher when the thyroid nodules with > 4 cm diameter were compared to the thyroid nodules with <4 cm diameter.

Large Cytologically Benign Thyroid Nodules Do Not Have High Rates of Malignancy or False-Negative Rates and Clinical Observation Should be Considered: A Meta-Analysis

Background: Management of large thyroid nodules is controversial, as data are conflicting regarding overall rates of malignancy (ROM) in all nodules and frequency of false-negative fine-needle aspiration results (FNR) in cytologically benign nodules. This meta-analysis aimed to evaluate and compare ROM and FNR in small versus large nodules published in the literature. Methods: Articles indexed in PubMed, written in English, published electronically or in print on or prior to December 8 2017 were searched for "false negative thyroid size or cm" and "malignancy rates benign thyroid nodules." Three hundred fifty-two unique citations were identified. Multiple reviewers selected a final set of 35 articles that contained nodules stratified by size (3, 4, or 5 cm), with benign or all cytologic diagnoses, and with postsurgical histologic diagnoses. Multiple observers extracted data, including numbers of total, cytologically benign, and histologically malignant nodules. Size cutoffs of 3, 4, and/or 5 cm were analyzed in 14, 24, and 1 article, respectively. Results: ROM in all nodules ≥3 cm (13.1%) and ≥4 cm (20.9%) was lower than those <3 cm (19.6%) and <4 cm (19.9%; odds ratio [OR] = 0.72 [confidence interval (CI) 0.64-0.81] and OR = 0.85 [CI 0.77-0.95]). FNR in nodules ≥3 cm (7.2%) was not different from smaller nodules (5.7%; OR = 1.47 [CI 0.80-2.69]). FNR in nodules ≥4 cm (6.7%) was slightly higher than those <4 cm (4.5%; OR = 1.38 [CI 1.06-1.80]). The most frequently reported false-negative diagnosis was papillary thyroid carcinoma. Conclusions: Rates of malignancy and false-negative FNA results vary but, in most studies, are not higher in larger nodules. Patients with large, cytologically benign thyroid nodules need not undergo immediate surgical resection, as false-negative FNA rates are low and are expected to decrease in light of nomenclature revision of a subset of follicular variants of papillary thyroid carcinoma.

Prevalence of Cancer in Thyroid Nodules In the Veteran Population

A 16-year retrospective chart review found no relationship between nodule size and malignancy, emphasizing the need for individualized care.

The risk of thyroid carcinoma in multinodular goiter compared to solitary thyroid nodules: A retrospective analysis of 600 patients

Background

It is generally believed that multinodular goiter (MNG) is associated with a lower risk of malignancy compared to solitary thyroid nodules (STN). This will be the null hypothesis in this retrospective study and we aim to prove or reject it.

Methods

Medical files and histopathology reports of 600 patients who underwent thyroidectomy over 4-year period were reviewed. Data including patient' age, gender, presentation, ultrasonography, FNAC, surgical procedures, final histopathologic diagnosis and stage of malignant tumors were collected and analyzed. The primary end point was assessment of risk of thyroid carcinoma in patients with MNG compared to those with STN. Secondary endpoints included demographic differences and prognosis.

Results

There were 459 females (76.5%). Mean age was 44.3 ± 14.5 years (range 14-85). After exclusion of 33 patients, 224 (39.5%) had STN and 343 (60.5%) had MNG. The prevalence of thyroid cancer was 41.1% (92/224) in STN compared to 29.2% (100/343) in MNG (Chi-Square = 8.593, p < 0.01). However, on multiple logistic regression analysis this correlation was found insignificant (p = 0.640). Only male gender (p = <0.000005) and preoperative impression of malignancy (p = 0.000082) were significantly associated with thyroid carcinoma.

Conclusion

The risk of thyroid carcinoma in STN and MNG was similar. Male gender was identified as a risk factor for thyroid cancer while age, number and size of nodules were not.