Adequacy of surgeon-performed ultrasound-guided thyroid fine-needle aspiration biopsy

OBJECTIVE: To determine the diagnostic accuracy of specimens obtained by a surgeon performing office-based ultrasound (US)-guided fine-needle aspiration biopsy (FNAB) of thyroid nodules. SUBJECTS AND METHODS: From 2003 to 2006, a single surgeon performed 447 consecutive office-based US-guided FNABs without on-site cytological specimen evaluation. Adequate specimens had at least six clusters of follicular cells from at least two separate needle passes. RESULTS: Non-diagnostic specimens occurred in 16 of 447 (3.6%) nodules, whereas suboptimal specimens occurred in 17 of 447 (3.8%). Adequate samples were obtained in 413 of 447 (92.6%) of specimens. Malignancy was present in 20 of 447 (4.5%) and atypical features were present in 37 of 447 (8.3%). Benign diagnoses were rendered in 357 of 447 (79.9%) of specimens, of which four of 357 (1.1%) represented false-negative results. CONCLUSION: Prior publications recommend that obtaining adequate thyroid cytology specimens requires use of US-guided FNAB and on-site evaluation of cytology adequacy. This study demonstrates that a combination of experienced US guidance, both capillary and aspiration sampling, and three to four needle passes produce comparable results while conserving costs and resources.     

超声引导下细针穿刺抽吸活检诊断甲状腺结节

目的探讨超声引导下细针穿刺抽吸活检(US-FNAB)对不同大小甲状腺结节的诊断价值。方法回顾分析在我院接受US-FNAB检查的689例患者736个甲状腺结节,超声测量结节最大径,并将其分为<5mm、5～10mm、>10mm组;对结节US-FNAB细胞学诊断结果与术后病理结果或随访结果进行比较,分析组间差异。结果 736个结节中,细胞学诊断恶性132个,可疑恶性61个,良性476个,不满意44个,不确定23个。经术后病理或临床随访,恶性结节208个,良性结节528个。恶性结节最大径小于良性结节(P<0.001)。5～10mm组结节的细胞学阳性率和实际恶性率均大于<5mm组及>10mm组(P均<0.05)。US-FNAB细胞学诊断甲状腺良恶性结节的敏感度为87.02%(181/208),特异度97.73%(516/528),准确率94.70%(697/736)。不同大小甲状腺结节US-FNAB检查的诊断敏感度、特异度、阳性预测值、阴性预测值及准确率差异均无统计学意义(P均>0.05)。结论 US-FNAB是判断甲状腺结节性质的有效手段,对不同大小结节都有较高诊断价值。     

The results of ultrasound-guided fine-needle aspiration biopsy for evaluation of nodular thyroid disease

BACKGROUND: The purpose of this study was to determine whether ultrasonography (US) improves the accuracy and reduces the rate of nondiagnostic fine-needle aspiration biopsy (FNAB) of thyroid nodules. METHODS: A review of 536 consecutive patients evaluated for nodular thyroid disease from 1990 to 2001 was completed to determine the results for US vs palpation-guided FNAB. RESULTS: FNAB was used to evaluate 458 patients. US-guided FNAB was performed in 66 (12%) patients: 48 with a nonpalpable nodule, 14 with nondiagnostic standard FNAB, and 4 with a palpable nodule. US-guided FNAB was nondiagnostic in 15 (23%) patients. There were no false-positive or false-negative results. Standard FNAB was performed in 407 patients, 57 (14%) of whom had a nondiagnostic result. There were 2 (3%) false-positive and 3 (1.6%) false-negative results. In 14 patients with a nondiagnostic standard FNAB, US-guided FNAB yielded an adequate specimen in 7 (50%). Nodules evaluated by standard FNAB were 4.1 +/- 0.1 cm (mean +/- SEM) in size compared with 2.5 +/- 0.1 cm for nodules evaluated by US-guided FNAB (P <.05). CONCLUSIONS: US improves the diagnostic yield in selected patients with nondiagnostic standard FNAB. The higher frequency of nondiagnostic US-guided FNAB was related to its selective use in patients with smaller nodules.     

The efficacy of simultaneous fine-needle aspiration and large-needle biopsy of the thyroid gland

Fine-needle aspirations and cutting needle biopsies were performed on 415 patients with solitary thyroid nodules. All nodules were considered hypofunctioning by scintiscans. Specimens were adequate in 399 patients. Ten percent of these patients had thyroid cancers documented by thyroidectomies. Results from either or both procedures were positive or suspicious in 58 patients (14.5%). Thyroid cancers were found in 40 of the 58 patients (69%). Aspirates alone detected 34 of 40 cancers (85%) and biopsy specimens alone detected 30 of 40 cancers (75%). All thyroid cancers were detected when both results were considered together, demonstrating that needle aspirates and cutting needle biopsies are complementary. The difficulty of making definitive diagnoses of follicular neoplasms by needle aspirates or cutting needle biopsies is reemphasized.     

Clinical value of fine-needle aspiration biopsy of the thyroid gland]

The work compares the results of fine-needle aspiration biopsy (FAB) of the thyroid gland in nodular and diffuse-nodular euthyroid goiter (63 patients) with the findings of pathomorphological study of the operative material (51 patients). The authors' original device for puncture of the thyroid node is described. The suggested method makes it possible to raise the efficacy of obtaining an adequate amount of aspired material to 92%. On the basis of the results of FAB and ultrasonic examination (USE) unfounded surgical intervention was avoided in 12 of the 63 cases. The results of the study bear evidence of the high diagnostic efficacy of FAB as to obtaining the cytologic material and revealing malignant degeneration (96% specificity). The authors believe that FAB in combination with USE should be an obligatory component of complex clinico-instrumental examination of patients with various diseases of the thyroid, nodular forms of affection in particular.     

Surgeon-performed ultrasound-guided thyroid fine-needle aspiration biopsy: Evaluation of 470 biopsies

Background

Ultrasound-guided FNAB of thyroid nodules is considered to be the most reliable and feasible test for the diagnosis of thyroid malignancy. We aimed specifically to assess the accuracy of surgeon-performed ultrasound (SPUG)-guided FNAB on a per-nodule basis, with a subanalysis of nodule size and on-site evaluation.

Materials and Method

During the study period, 470 thyroid FNABs were performed. In the first 155 biopsies, the attending pathologist determined the adequacy of the specimen based on the number of cells. Nodules were categorised as group A: nodule size <1.99 cm and group B: nodule size >2 cm in width. The FNAB results were classified and described according to the Bethesda system.

Results

The overall non-diagnostic rate of ultrasound-guided thyroid FNAB in this study was 10% (47 of 470). The percentage of non-diagnostic cases was 12.06% (38 of 315) in patients without on-site evaluation and 5.8% (9 of 155) in patients with on-site evaluation; this difference did not reach statistical significance (p = 0.051). The nondiagnostic FNAB rates were 10.6% (42 of 395) and 6.6% (5 of 75) with respect to nodule sizes <1.9 cm and >2 cm. Although nodules smaller than 1.9 cm had higher non-diagnostic FNAB rates, these results were not statistically significant (p = 0.401).

Conclusion

In conclusion, this study demonstrates that ultrasound-guided FNAB in the hands of an experienced surgeon can be performed with a low non-diagnostic FNAB rate.     

超声引导下细针穿刺细胞学检查术前评估甲状腺结节

目的探讨超声引导下细针穿刺细胞学检查(UG-FNAB)术前评估甲状腺结节良恶性的价值。方法对870例患者共1 024个常规超声筛选高度可疑恶性的甲状腺结节行UG-FNAB,并与手术病理进行对照研究。结果 1 024个可疑甲状腺恶性结节中,UG-FNAB检查结果阳性结节902个,阴性结节122个。手术病理结果示恶性结节918个,良性结节106个。UG-FNAB诊断结果与手术病理学诊断结果的差异无统计学意义(χ~2=1.263,P=0.261)。UG-FNAB诊断甲状腺结节的敏感度为97.71%(897/918)、特异度为95.28%(101/106)、阳性预测值为99.45%(897/902)、阴性预测值为82.79%(101/122)、准确率为97.46%(998/1 024)。870例UG-FNAB后均未发生严重并发症。结论 UG-FNAB对于术前评估甲状腺结节良恶性具有较高的应用价值。     

超声引导下细针抽吸活检诊断不同大小甲状腺结节

目的探讨甲状腺结节大小对超声引导下细针抽吸活检(US-FNAB)诊断效能的影响。方法选取接受USFNAB且病理证实为甲状腺结节的患者125例(共143个结节),根据结节最大直径(L)分为3组:A组(L≤10mm),B组(10mmL≤15mm),C组(L15mm)。将US-FNAB细胞学诊断结果与病理结果对比,并进行统计学分析。结果143个结节中US-FNAB细胞学诊断阳性结节94个,阴性结节49个;术后病理诊断恶性结节96个,良性结节47个。良、恶性结节大小差异有统计学意义(P0.001)。3组敏感度、特异度差异均有统计学意义(P均0.05),阳性预测值、阴性预测值、假阳性率、假阴性率及准确率差异均无统计学意义(P均0.05)。与A、B组比较,C组敏感度最低(P0.05),A、B组敏感度差异无统计学意义(P0.05)。与B、C组比较,A组特异度最低(P0.05),B、C组特异度差异无统计学意义(P0.05)。结论甲状腺结节大小对US-FNAB诊断的效能无影响。     

Nodule size and fine-needle aspiration biopsy: diagnostic challenges for thyroid malignancy

Background

To investigate the relationship between nodule size and malignancy and the correlation between the dimensional parameter and fine-needle aspiration biopsy (FNAB) in patients with a nodular goiter.

Methods

Histological data of 415 patients who underwent thyroidectomy were used to estimate the actual nodule size and the difference between the diameter of the nodular lesion and the included tumor (intranodular peritumoral tissue [IPT]). FNAB was performed in 338 patients, and its predictive role was evaluated in comparison with histology.

Results

The histology revealed 207 cases of thyroid malignancy. The mean nodule size was significantly larger in benign disease compared with malignant. Only age and FNAB malignant category were independently associated with malignancy. The IPT showed a trend toward a statistically significant association with FNAB malignant category.

Conclusions

Nodule size does not appear to be a reliable parameter to improve the clinical management of a nodular goiter because of a high variability between size of nodular area and tumor diameter.     

Diagnostic accuracy of fine-needle aspiration biopsy versus frozen section in solitary thyroid nodules

Fine-needle aspiration biopsy is widely used in the diagnosis and management of the solitary thyroid nodule. It is the most accurate tool available and decreases the need for ultrasonography and thyroid scanning. In those patients who are selected for surgical treatment by fine-needle aspiration biopsy, it has been advocated as a guide to determining the extent of operation. Frozen section, which usually serves as the surgeon's guide, and fine-needle aspiration biopsy both have varying accuracy rates. Few direct comparisons have been made. We studied 198 aspirates in 198 patients who presented with a solitary nodule and had surgical excision. Fine-needle aspiration biopsy (198 cases) and frozen section (182 cases) were compared with the final histologic diagnosis. Accuracy rates for fine-needle aspiration biopsy and frozen section were 90 percent and 95 percent, respectively. Fine-needle aspiration biopsy detected 43 percent of the cancers and frozen section, 64 percent. There were no false-positive diagnoses with frozen section, but three cases with fine-needle aspiration biopsy. The false-negative diagnosis rate was 5 percent for frozen section and 8.5 percent for fine-needle aspiration biopsy. When the "other" diagnosis category was grouped with the "positive" diagnosis category and a single expert cytopathologist was used to read the cytology report, the sensitivity was increased to 80 percent whereas the accuracy was maintained at 83 percent. We believe that since there were no false-positive diagnosis using frozen section, it can reliably be used as a guide when it reveals malignancy. When the fine-needle aspiration biopsy diagnosis is "positive" or "other," it can guide operation, but only after carefully assessing the wording of the cytology report and the clinical situation. Each modality can provide information missed by the other. We continue to use them as complementary tools in the diagnosis and management of solitary thyroid nodules.     

When fine-needle aspiration biopsy cannot exclude papillary thyroid cancer: a therapeutic dilemma

HYPOTHESIS: Clinical or cytologic factors predictive of malignancy can be identified and incorporated into a treatment algorithm for patients with a fine-needle aspiration biopsy (FNAB) specimen interpreted as "suspicious for" papillary thyroid cancer (PTC). DESIGN: Retrospective review of a prospectively maintained database. SETTING: University-affiliated tertiary care hospital. PATIENTS: Seven hundred thirty-eight patients with nodular thyroid disease evaluated between 1990 and 2004. INTERVENTIONS: Patients with an FNAB specimen suspicious for PTC were identified. The frequency of carcinoma was determined. Clinical features were reviewed. The FNAB specimens suspicious for PTC were examined in a blinded fashion to determine if specific cytologic features were important in distinguishing benign vs malignant disease. MAIN OUTCOME MEASURES: The presence of specific clinical and cytologic features was correlated with the incidence of carcinoma. A secondary outcome measure was to determine the value of frozen section examination in establishing the extent of thyroidectomy. RESULTS: Forty-five patients (7%) had an FNAB specimen suspicious for PTC; 18 (40%) of these patients had carcinoma. Prominent nuclear inclusions and/or grooves, papillary formations, and the absence of colloid were features associated with PTC (P<.05). No clinical features reliably identified malignant disease. Frozen section examination results altered treatment in 15 (56%) of 27 patients. CONCLUSIONS: An FNAB specimen suspicious for PTC is associated with a 40% incidence of carcinoma. Extensive nuclear inclusions and/or grooves, papillary formations, and the absence of colloid are predictive of carcinoma. Rare intranuclear inclusions and/or grooves alone in an otherwise benign-appearing specimen are uniformly associated with benign disease. Frozen section examination is of value in determining the extent of thyroidectomy.     

Recent experience with preoperative fine-needle aspiration biopsy of thyroid nodules in a community hospital

HYPOTHESIS: The application and reliability of fine-needle aspiration (FNA) biopsy in community hospitals may be less efficacious in the clinical assessment of patients with thyroid nodules than in tertiary referral centers. DESIGN: Retrospective review. SETTING: One community teaching hospital. PATIENTS: One hundred eighty-three patients who underwent thyroidectomy after FNA biopsy. INTERVENTIONS: Preoperative FNA biopsy cytopathologic testing and thyroidectomy and postoperative histopathologic testing. MAIN OUTCOME MEASURE: Preoperative cytopathologic reports were compared with postthyroidectomy histopathologic reports. RESULTS: Thyroid cancer was confirmed postoperatively in 70 patients (38%). An FNA biopsy diagnosis of papillary carcinoma (in 29 patients) correlated with a predictive accuracy of 93% (27 patients). Suspicious for papillary carcinoma (n = 14) correlated with malignancy in 8 patients (57%). Indeterminate follicular lesion (n = 60) correlated with malignancy in 18 patients (30%), of whom 16 (89%) had papillary carcinoma (10 patients had follicular variant) and 2 (11%) had follicular carcinoma. Indeterminate Hürthle cell lesion (n = 20) correlated with malignancy in 7 patients (35%). Atypical cell clusters (n = 5) did not correlate with malignancy. Benign FNA biopsy findings (n = 44) in patients who underwent thyroidectomy for other clinical features correlated with malignancy in 8 (18%). Of 11 patients who underwent thyroidectomy for insufficient number of cells after repeated FNA biopsy attempts, 2 (18%) had carcinoma. CONCLUSIONS: The accuracy of an FNA biopsy of thyroid nodules in a community hospital setting is comparable to results from major endocrine referral centers. An indeterminate follicular lesion was the most common FNA biopsy indication for thyroidectomy and correlated with the presence of differentiated thyroid cancers in 18 (30%) of 60 patients.     

Single versus sequential fine-needle aspiration biopsy in the management of thyroid nodular disease.

Fine-needle aspiration biopsy (FNAB) is considered a safe, reliable and cost-effective means of selecting thyroid nodules with risk for malignancy. However, there are limitations of this method including false positive/negative and "nondiagnostic" results that may be reduced by repeating FNAB. OBJECTIVE: To evaluate accuracy, sensitivity, specificity and costs of sequential FNAB in the management of thyroid nodular disease. METHODS: Charts of all patients who underwent thyroidectomy at a university teaching hospital in Toronto from 1998 to 2000 were reviewed. FNAB reports of "suspicious for malignancy," "follicular lesion" and "cellular atypia" were considered to be positive. Data were analyzed with chi2 and z tests. RESULTS: There were 268 patients (225 women and 43 men; age range 18-89 yr; mean age 47 yr) who underwent a total of 449 FNABs (mean 1.7 FNABs/patient) within a year before thyroidectomy. Accuracy (63.8%), sensitivity (73.8%) and specificity (69%) were determined for single FNABs. Sequential FNAB increased the accuracy of method by 22.6%, sensitivity by 13.8% and specificity by 6.2%, with reduction of false positive/negative results by 14.2% and "nondiagnostic" results by 100%. However, the costs of sequential cytology per patient were 70% higher than single FNAB. CONCLUSIONS: Multiple FNABs are unpleasant for patients, but useful in the selection for treatment of patients with thyroid nodular diseases. Although sequential FNAB increases the costs of method, the improvement of precision of FNAB may imply a reduction in overall health-care costs.     

The efficiency of performing ultrasound-guided fine-needle aspiration biopsy following mass screening for thyroid tumors to avoid unnecessary surgery

Thyroid masses are a common clinical finding, and their management remains controversial. The purpose of this study was to evaluate the clinical effect of performing routine ultrasound (US) examinations and US-guided fine-needle aspiration biopsy (US-FNAB) in the management of diffuse or nodular goiter diagnosed by mass screening. Mass screening carried out from 1993 to 1996 revealed 444 women with goiter, 322 of whom had diffuse goiter and 122 had nodular goiter. All of these patients underwent US examination, the results of which determined that 169 should undergo US-FNAB to confirm an accurate diagnosis of their thyroid tumors. Histological examinations after surgical resection revealed that 12 of the 322 patients with diffuse goiter (3.7%) and 23 of the 122 with nodular goiter (18.9%) had malignant tumors. Among the 61 thyroid tumors surgically verified, US-FNAB yielded a sensitivity rate of 93%, a specificity rate of 81%, and an accuracy rate of 90%. Insufficient aspiration was obtained from 5%. Performing US-FNAB-resulted in an elevation in the percentage of malignant tumors yielded at surgery of up to 72%. Thus, ultrasonography followed by US-guided-FNAB could be a useful routine method of evaluating thyroid tumors detected by mass screening. Moreover, a greater number of unnecessary thyroid operations can be avoided by performing US-FNAB rather than FNAB alone.     

Role of fine-needle aspiration biopsy and frozen-section evaluation in the surgical management of thyroid nodules

BACKGROUND: The role of routine frozen section (FS) in the surgical management of thyroid nodules remains uncertain. This study reviewed the role of FS in the presence of an adequate fine-needle aspiration biopsy (FNAB). METHODS: FNAB and FS were evaluated in 206 patients who had surgery for a thyroid nodule. Cytological specimens were classified as benign, malignant or suspicious. The FS diagnoses were benign, malignant or deferred. RESULTS: A cytological diagnosis was obtained in 93 nodules; the remaining 113 were classified as suspicious, of which 21 were malignant on definitive examination. The overall accuracy of FNAB was 53 per cent. FS evaluation identified 165 lesions as benign; the diagnosis was deferred until definitive histological evaluation in only eight. The overall accuracy, therefore, was 96 per cent. Routine use of FS was cost-effective; lowering the number of reoperations led to an estimated saving of about 40 per cent. CONCLUSION: These data suggest that FS remains an important tool in the surgical management of thyroid nodules and can reduce the number of patients requiring reoperation.     

False-negative errors in fine-needle aspiration biopsy of dominant thyroid nodules: A prospective follow-up study

Reluctance to adopt fine-needle aspiration (F-NA) of dominant thyroid nodules stems largely from fear of overlooking a malignancy in a nodule diagnosed as benign on FNA (false-negative error). Published error rates have been derived from surgical series without regard to the outcome of those who were followed without operation. In order to ascertain the overall false-negative error rate, we conducted a prospective study in 600 patients who underwent FNA. Among the 482 study patients who had a benign FNA diagnosis or inadequate specimens, 117 underwent surgery because of the concurrent large-needle biopsy result or a clinical suspicion of malignancy. Eight false-negative errors were identified in this group, 5 of which were detected by large-needle biopsy. Among the remaining 365 patients who were followed for an average of 2 1/2 years, 2 patients were found to have well-differentiated carcinomas in recurrent cysts. The overall false-negative error rate of FNA alone in all 482 patients was 2.1%. This was reduced to 1.0% by the use of concurrent large-needle biopsy. Properly applied, FNA can reduce unnecessary surgery among patients with clinically benign nodules without incurring an unacceptably high false-negative error rate. Furthermore, this error rate may be reduced substantially by combining large-needle biopsy with FNA and by close follow-up with surgery performed later in patients who manifest clinical features suggestive of malignancy.

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Resumen El rechazo a la adopción de la aspiración con aguja fina (AAF) de nódulos tiroideos dominantes se origina principalmente en el riesgo de que pase desapercibida una neoplasia maligna en un nódulo que haya sido diagnosticado como benigno en AAF (error falso-negativo). Las tasas de error publicadas se derivan de series quirúrgicas que no tienen en consideración el resultado final en aquellos pacientes que han sido sometidos a seguimiento sin operación. Con el objeto de establecer la tasa global de resultados falsos-negativos, nos propusimos realizar un estudio prospectivo en 600 pacientes sometidos a AAF. Entre los 482 pacientes del presente estudio que presentaron diagnóstico de lesión benigna a la AAF o en quienes el espécimen fue inadecuado, 117 fueron sometidos a operación debido a diagnóstico concurrente con aguja gruesca o a sospecha clínica de malignidad. Se identificaron 8 falsos-negativos en este grupo, 5 de los cuales fueron detectados mediante biopsia con aguja gruesa. En cuanto a los restantes 365 pacientes que fueron seguidos por un promedio de 2 1/2 años, en 2 pacientes se hallaron carcinomas bien diferenciados en quistes recurrentes. La tasa global de error falsonegativo en la AAF sola fue de 2.1% para el total de 482 pacientes. Esta se redujo a 1.0% mediante el uso de la biopsia concurrente con aguja gruesa. Cuando es debidamente aplicada, la AAF reduce la cirugía innecesaria en pacientes con nódulos clínicamente benignos sin incurrir en una tasa inaceptablemente elevada de resultados falsosnegativos. Además, tal tasa de error puede ser sustancialmente reducida al combinar la biopsia con aguja gruesa con la AAF y mediante cuidadoso seguimiento y la realización de intervención quirúrgica ulterior en aquellos pacientes que exhiban características clínicas sugestivas de malignidad.

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Résumé La prévention qui règne contre l'emploi de la biopsie aspiration à l'aiguille fine pour déterminer la nature des nodules thyroïdiens provient de la crainte de méconnaitre la malignité d'un noyau considéré comme bénin. Pour déterminer le taux total des faux négatifs les auteurs ont procédé à une étude prospective de 600 malades qui ont été soumis à la biopsie aspiration. Parmi les 482 sujets qui présentèrent un diagnostic de bénignité selon les données de la biopsie à l'aiguille fine ou des spécimens inadéquats, 117 furent opérés en raison du résultat de la biopsie à la grosse aiguille ou de facteurs cliniques de malignité. Huit faux-négatifs ont été relevés dans ce groupe, dont 5 furent corrigés par la biopsie à l'aiguille classique. Parmi les autres 365 sujets qui furent suivis en moyenne 2.5 ans, 2 présentèrent un cancer thyroïdien bien différencié au niveau de kystes récidivants. Au total le taux des faux-négatifs dûs à la biopsie à l'aiguille fine n'atteint que 2.1% pour une série de 482 malades et ce taux s'est trouvé réduit à 1% par l'emploi de la biopsie classique à la grosse aiguille. Employée correctement la biopsie à l'aiguille fine peut éviter la chirurgie inutile parmi les sujets porteurs d'un nodule cliniquement bénin et ceci sans courir le risque d'un taux élevé et inacceptable de faux négatifs. Plus encore ce taux peut être nettement réduit en associant la biopsie classique à la biopsie à l'aiguille fine et en suivant cliniquement avec attention les porteurs de nodules pour les opérer s'ils présentent des faits cliniques suggérant la malignité.

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Presented at the International Association of Endocrine Surgeons in Paris, September 1985.

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Supported by grants from the University Research Grants Committee, the Medical Faculty Research Grant Fund, and the Pauline Chan Medical Research Fund of the University of Hong Kong.