Cytological Diagnosis Of Follicular Neoplasm Research Articles

Risk Stratification in Patients With Follicular Neoplasm on Cytology: Use of Quantitative Characteristics and Sonographic Patterns.

ObjectivesDifferentiating thyroid nodules with a cytological diagnosis of follicular neoplasm remains an issue. The goal of this study was to determine whether ultrasonographic (US) findings obtained preoperatively from the computer-aided detection (CAD) system are sufficient to further stratify the risk of malignancy for this diagnostic cytological category.MethodsFrom September 2016 to September 2018 in our hospital, patients diagnosed with Bethesda category IV (follicular neoplasm or suspicion of follicular neoplasm) thyroid nodules and underwent surgical excisions were include in the study. Quantification and analysis of tumor features were performed using CAD software. The US findings of the region of interest, including index of composition, margin, echogenicity, texture, echogenic dots indicative of calcifications, tall and wide orientation, and margin were calculated into computerized values. The nodules were further classified into American Thyroid Association (ATA) and American College of Radiology Thyroid Imaging Reporting & Data System (TI-RADS) categories.Results92 (10.1%) of 913 patients were diagnosed with Bethesda category IV thyroid nodules. In 65 patients, the histological type of the nodule was identified. The quantitative features between patients with benign and malignant conditions differed significantly. The presence of heterogeneous echotexture, blurred margins, or irregular margins was shown to have the highest diagnostic value. The risks of malignancy for nodules classified as having very low to intermediate suspicion ATA, non-ATA, and high suspicion ATA patterns were 9%, 35.7%, and 51.7%, respectively. Meanwhile, the risks of malignancy were 12.5%, 26.1%, and 53.8% for nodules classified as TIRADS 3, 4, and 5, respectively. When compared to human observers, among whom poor agreement was noticeable, the CAD software has shown a higher average accuracy.ConclusionsFor patients with nodules diagnosed as Bethesda category IV, the software-based characterizations of US features, along with the associated ATA patterns and TIRADS system, were shown helpful in the risk stratification of malignancy.

Follicular neoplasm of thyroid in a young female: a case report from central India

Thyroid FNAC is very common but its interpretation is difficult. A 16‑year‑old female patient presented with a single thyroid nodule. A cytologic diagnosis of follicular neoplasm was made on fine needle aspiration cytology (FNAC). Papanicolaou and May–Grunwald–Giemsa staining showed high cellularity, abundant micro-follicles, cell crowding and uniform nuclear morphology. Reporting was done according to Bethesda system. The distinction between Follicular neoplasm and Nodular goiter is the most common differential diagnostic problem in solitary nodules as cytological appearances overlap. Findings were suggestive of follicular neoplasm which is rare in this age group.

Correlation between fine needle aspiration cytology and histopathological examination in thyroid swellings-a pilot study

Background: Thyroid swellings are an enigma that necessitates either, a partial thyroidectomy and a tissue diagnosis to be followed by completion surgery or straightaway a radical intervention. A preoperative presumptive diagnosis of a thyroid swelling, solitary or otherwise is correlated with the post-surgical histopathological finding in the present study.Methods: 30 patients of thyroid nodules were selected from the head-neck tumour clinic of Dayanand medical college hospital, Ludhiana. Pre-operative fine needle aspiration cytology (FNAC) was performed and subjects taken for thyroidectomy, partial or total as the case maybe.Results: There were 20 (66.6%) females in the age group 25-65 years and 10 males (33.3%) 19-50 years with thyroid nodules. 86.6%, 26 patients were of follicular adenoma, 10% 3 patients of papillary carcinoma and 3.33% 1 patient of follicular carcinoma. No case in this study was reported as medullary carcinoma. In the cytological diagnosis of follicular neoplasm in 5 cases, 3 were diagnosed as thyroid adenoma, 2 were finally found to be papillary carcinoma. Overall sensitivity of fine needle aspiration was 40%. There was 84.6% agreement in follicular adenoma; 33% in papillary carcinoma and 100% in follicular carcinoma, and overall accuracy was 85.7%.Conclusion: FNAC is an ideal preoperative investigative modality in thyroid swellings with overall accuracy of 85 % and can differentiate preoperatively a benign from a malignant thyromegaly; and thereby plan extent of surgery, with or without a neck dissection, Maximum cases of follicular adenoma could be easily diagnosed with this aspiration modality.

The Value of Fine-Needle Aspiration Biopsy (FNAB) in Differential Diagnosis of Scintigraphic Cold Thyroid Nodule.

Introduction:Pathology of thyroid nodules is present in all ages and it is frequently encountered in clinical practice. Thyroid nodules do not represent a single disease, but they are the clinical manifestation of a wide range of different thyroid diseases.Aim:The objective of this study is to evaluate the frequency and localization of malignancy in solitary scintigraphic cold nodules, as well as the sensitivity, specificity and diagnostic accuracy of FNAB in comparison with histopathological findings.Methods:The study was included 49 patients with palpatory findings of the solitary nodule located in the both lobes or isthmus of thyroid gland. All subjects underwent the scintigraphy and FNAB, followed by a cytologic results that was compared to the final histopathological diagnosis, after surgery.Results:The study results show that the highest number of solitary nodules (81,6%) is localized in the lower pole of the both lobes of the thyroid gland. The cytologic results were benign 8 cases, malignant in 23 and indeterminate (follicular neoplasm) in 18 cases. The highest number of thyroid cancer is histopathologically confirmed in the patients with cytological diagnosis of follicular neoplasms, i.e. follicular cancer is found in 66.7% and papillary cancer is found in 33.3% of subjects. The most common cancer is papillary cancer found in 61,2%. Since the pathohistological diagnosis of all our patients responded to cancer, it was done indirect statistical evaluation of the diagnostic sensitivity of cytological method in the estimation of malignant thyroid lesion, which was 83,7%.Conclusion:FNAB is a highly sensitive method in the diagnostics of malignant thyroid lesions with the sensitivity Se=83,7%. The highest number of thyroid cancer is histopathologically confirmed in the patients with cytological diagnosis of follicular neoplasm (66.7%). The highest number of patients had a cytological diagnosis of papillary cancer.

Predictive Factors of Malignancy in Cytology of Indeterminate Follicular and Hürthle Cell Neoplasms of the Thyroid Gland

The objective of the current study was to determine the risk of malignancy in patients with thyroid nodules with cytology of indeterminate follicular and indeterminate Hürthle cell neoplasm (HN). The cytologic diagnosis of follicular neoplasm (FN) or HN remains a diagnostic challenge. Often, surgery is recommended for such lesions. A retrospective analysis was performed on 80 patients who underwent thyroid surgery following a diagnosis of indeterminate FN and indeterminate HN in thyroid fine-needle aspiration biopsy. Sex; age; family history of thyroid cancer and radiation exposure; coexisting thyroid conditions, such as solitary nodule; multinodularity; cytologic diagnosis; sonographic features; type of surgical treatment; and histopathologic results were recorded. Of the 80 patients, 52 (65%) had FN on fine-needle aspiration biopsy cytology and 28 (35%) had HN. A total of 23 patients (28.7%) had primary thyroid cancers on surgical pathology, and 57 (71.3%) had benign diagnoses. Univariate analysis showed no differences between the benign and malignant groups by sex, nodule size, family history of thyroid cancer, history of radiation exposure, presence of solitary nodule or multinodularity in the nodular features. In multivariate binary logistic regression analysis, the factors that were statistically significant predictors of malignancy were microcalcification [odds ratio (OR), 10.9; 95% confidence interval (CI), 2.18–54.7; P = 0.004], being older than 45 years (OR, 4.2; 95% CI, 1.25–14.63; P = 0.02]. The independent predictors of malignancy in FN and HN are micorcalcification and being older than 45 years, the use of which may predict the risk of thyroid cancer.

Value of sonographic features in predicting malignancy in thyroid nodules diagnosed as follicular neoplasm on cytology.

The cytological diagnosis of follicular neoplasm (Thy3F) remains a diagnostic challenge. The main aim of this study was to stratify the risk of malignancy in thyroid nodules diagnosed as Thy3F on cytology (Thy3F) using thyroid imaging reporting and data system (TIRADS). A database of thyroid nodules with Thy3F cytological results from ultrasound-guided FNA (US-FNA) between January 2007 and March 2014 was studied retrospectively. Information on patient demographics, ultrasound characteristics and final histology of the nodules was collated. The number of suspicious US features of each thyroid nodule was counted based on TIRADS. The malignancy rate of each of the TIRADS category was also calculated based on the final histological outcomes of the nodules and compared to that calculated using a recently proposed thyroid malignancy risk prediction model. The overall malignancy rate of Thy3F cytology was 24·3%. There were significantly higher percentages of malignant nodules with irregular margins (20·0% vs 0%, P = 0·000), hypo-echogenicity (74·3% vs 51·4%, P = 0·013) and taller-than-wide morphology (17·1% vs 0·9%, P = 0·001) when compared to benign nodules. The risk of malignancy increased with advancing TIRADS score: TIRADS 4A (14·3%), TIRADS 4B (23·1%), TIRADS 4C (87·5%) and TIRADS 5 (100%). The malignancy rate calculated using the prediction model similarly increased with advancing TIRADS score: TIRADS 4A (6·2%), TIRADS 4B (32·5%), TIRADS 4C (79·9%) and TIRADS 5 (90%). Thyroid nodules with TIRADS scores 4C and 5 should be considered for single definitive surgery in view of the high malignant rate.

Hürthle cells in fine‐needle aspirates of the thyroid: A review of their diagnostic criteria and significance

Although the cytological assessment of Hürthle cell lesions is challenging, the literature offers good, albeit imperfect, guidance to aid in the crucial distinction between nonneoplastic and neoplastic lesions. The significance of a cytologic diagnosis of follicular neoplasm, Hürthle cell type, lies in the rate of malignancy on follow-up surgical excision, ranging in the literature from 10% to 45%. A cytodiagnosis of atypia of undetermined significance (AUS), Hürthle cell type, appears to be associated with a lower risk of malignancy on follow-up than other subtypes of AUS; however, this area warrants further investigation.

Predictive Factors of Malignancy in Thyroid Nodules with a Cytological Diagnosis of Follicular Neoplasm

In cases of follicular neoplasm identified by thyroid fine-needle aspiration (FNA), surgery is required to achieve a precise diagnosis. We investigated potential clinical factors for the preoperative prediction of malignancy in thyroid nodules with a cytological diagnosis of follicular neoplasm. We retrospectively reviewed the data of 97 patients who were diagnosed with follicular neoplasm by FNA and had undergone surgery at the Korea Cancer Center Hospital between April 2010 and April 2012. Age, sex, laboratory data (such as thyroid-stimulating hormone, free T4, thyroglobulin (Tg), and Tg antibody), and ultrasonographic findings were reviewed from the electronic medical records. Of 97 patients, 50 (51.5%) were diagnosed with benign nodules, 16 (16.5%) with follicular thyroid carcinoma (FTC), and 31 (32.0%) with papillary thyroid carcinoma (PTC). In comparison with the features of benign nodules, FTC presented with a large nodule size, high serum Tg level, isoechogenicity, calcifications, and peripheral halo, whereas PTC exhibited traits similar to those of benign nodules, except for high serum Tg level and the presence of calcifications on ultrasonography. Therefore, a high serum Tg level (≥75ng/mL) and calcification were the only significant predictive factors for malignancy in case of follicular neoplasm (p < 0.01). Serum Tg levels and the presence of calcification on ultrasonography are important clinical features to predict malignancy in thyroid nodules with cytological diagnosis of follicular neoplasm.

Could 18F-FDG-PET/CT avoid unnecessary thyroidectomies in patients with cytological diagnosis of follicular neoplasm?

Preoperative diagnosis of thyroid nodules with "follicular neoplasm" (FN) based on fine-needle aspiration cytology (FNAC) forces thyroidectomy to exclude malignancy. This study explores if (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) provides information enough to prevent unnecessary thyroidectomies in this clinical setting. This is a prospective study involving 46 consecutive patients scheduled for thyroidectomy due to follicular neoplasm diagnosis in FNAC (36 follicular, 10 Hürthle cell neoplasms, Bethesda classification) since January 2009 until April 2012. All patients underwent preoperative (18)F-FDG-PET/CT. Abnormal (18)F-FDG thyroid uptake was assessed visually and by measuring the maximum standard uptake value (SUV max). Results were compared with definitive pathology reports. Thirteen out of 46 patients (28.3 %) were finally diagnosed with thyroid cancer. Focal uptake correlated with a greater risk of malignancy (p = 0.009). (18)F-FDG-PET/CT focal uptake showed sensitivity, specificity, positive and negative predictive values and overall accuracy of 92.3, 48.5, 41.4, 94.1 and 60.9 %, respectively. The optimal threshold SUV max to discriminate malignancy was 4.2 with an area under receiver-operating characteristic curve of 0.76 (95 % confidence interval, 0.60-0.90). Use of (18)F-FDG-PET/CT could reduce by 13-25 % the number of thyroidectomies performed for definitive benign nodules. However, it has demonstrated worse predictive ability in the subgroup of patients with diffuse uptake, oncocytic pattern in FNAC and lesions smaller than 2. (18)F-FDG-PET/CT can play a role in the management of thyroid nodules larger than 2 cm cytologically reported as follicular neoplasm without oncocytic differentiation, allowing the avoidance of a significant number of thyroidectomies for definitive benign lesions.

Follicular carcinoma in a 9-year-old child: A case report and review of literature

Thyroid cancer is rare in children and is mostly of the papillary carcinoma histologically. Follicular carcinoma constitutes 10-20% of all primary thyroid cancers with the age peak at the fourth and fifth decades. Iodine deficiency appears to be the main contributing factor for follicular carcinoma because iodine supplementation to the diet has been associated with a decline in the incidence of this tumor in iodine-deficient areas. A 9-year-old female patient who was under treatment for hypothyroidism presented with a single thyroid nodule, which on fine needle aspiration cytology, a cytologic diagnosis of follicular neoplasm was made. A histological diagnosis of minimally invasive follicular carcinoma was done after subtotal thyroidectomy. This case was presented with review of the literature.

Risk of malignancy in follicular thyroid neoplasm

SummaryThe cytological diagnosis of follicular neoplasm is a common finding in fine needle aspiration cytology (FNAC) of thyroid nodules and includes benign disease as well as differentiated thyroid cancer. The aim of the study is to determine if thyrotropin is a predictive factor for a malignant nature of follicular neoplasm. Patients, methods: The records of 119 patients with follicular neoplasm on FNAC, who underwent surgery for final diagnosis, were reviewed retrospectively. The predictive value of serum parameters including thyrotropin, thyroglobulin, and anti-thyroid antibodies, ultrasonographic criteria and clinical variables was evaluated by univariate analysis and logistic regression analysis. Results, discussion: Patients with malignant nodules showed a higher thyrotropin concentration compared to patients with benign nodules (median 1.6 mU/l, interquartile range 1.4–3.0 mU/l vs. median 1.2 mU/l, interquartile range 0.8–1.6 mU/l, p &lt; 0.01). ROC-analysis of thyrotropin revealed an optimal cut off value to differentiate benign and malignant nodules of 1.34 mU/l. The incidence of malignancy was 30.3% for a thyrotropin concentration higher than 1.34 mU/l compared to 6.4% for a thyrotropin concentration lower than or equal to 1.34 mU/l. On univariate analysis thyroglobulin higher than 300 ng/ml, positive anti-thyroid antibodies, hypoechogenicity, and ill-defined margins, respectively, were also significantly associated with malignancy. On logistic regression analysis higher thyrotropin concentrations, ill-defined margins, and thyroglobulin higher than 300 ng/ml, respectively, were independent predictive factors for malignancy (OR 20.0, 10.7, and 22.7, respectively). Conclusion: Higher thyrotropin concentrations are predictive for a malignant nature of follicular neoplasm.

Follicular thyroid neoplasms can be classified as low- and high-risk according to HBME-1 and Galectin-3 expression on liquid-based fine-needle cytology

Fine-needle aspiration biopsy (FNAB) is the most reliable diagnostic tool in the diagnosis of thyroid nodules. A cytologic diagnosis of follicular neoplasm with atypical cells of undetermined significance (FN/AUS) implies that the selection of patients between surgery and follow-up is difficult. In this setting immunocytochemical stainings might be helpful. The efficacy of a panel made up of HBME-1 and Galectin-3 antibodies is evaluated in cases processed by liquid-based cytology (LBC). Out of 7091 thyroid FNAB processed by LBC method, 120 cases undergoing surgery successively were selected. These cases were classified as benign lesion (BL, eight cases), FN, including the ACUS category of the Bethesda classification (FN/AUS, 50 cases), suspicious for malignancy (SM, 59 cases), and malignant neoplasm (MN, three cases). Immunostains for HBME-1 and Galectin-3 were carried out on the LBC slides. All MN and BL were histologically confirmed. FN/AUS and SM showed a malignancy risk of 24 and 72.9% respectively. The complete immunocytochemical panel was positive in 83.3% of the cases resulting in malignancy and negative in 87.5% of cases resulting in benign histology. Among the FN/AUS, the complete positive immunocytochemical panel was detected in 76.9% of cases resulting as malignant and the complete negative immunocytochemical panel was observed in 96.8% of cases resulting as benign at histology. The expression of HBME-1 and Galectin-3 in cases classified as FN/AUS on LBC-processed FNABs can effectively distinguish lesions, which need immediate surgery (high risk or FNH or Thy 3h) from those which can be followed-up (low risk or FNL or Thy 3l).

Letter: Postoperative Findings of the Cytological Diagnosis of Follicular Neoplasm or Hürthle Cell Neoplasm and the Risk of Malignancy

1. Baloch ZW, Sack MJ, Yu GH, Livolsi VA, Gupta PK: Fine-needle aspiration of thyroid: an institutional experience. Thyroid 8:565-569, 1998 2. DeMay RM: Follicular lesions of the thyroid. W(h)ither follicular carcinoma? Am J Clin Pathol 114:681-683, 2000 3. Haugen BR, Woodmansee WW, McDermott MT: Towards improving the utility of fine-needle aspiration biopsy for the diagnosis of thyroid tumours. Clin Endocrinol (Oxf) 56:281-290, 2002 4. Sapio MR, Posca D, Raggioli A, Guerra A, Marotta V, Deandrea M, Motta M, Limone PP, Troncone G, Caleo A, Rossi G, Fenzi G, Vitale M: Detection of RET/PTC, TRK and BRAF mutations in preoperative diagnosis of thyroid nodules with indeterminate cytological findings. Clin Endocrinol (Oxf) 66:678-683, 2007

Response: Postoperative Findings of the Cytological Diagnosis of Follicular Neoplasm or Hürthle Cell Neoplasm and the Risk of Malignancy

Response: Postoperative Findings of the Cytological Diagnosis of Follicular Neoplasm or Hürthle Cell Neoplasm and the Risk of Malignancy

Postoperative Findings of the Cytological Diagnosis of Follicular Neoplasm or Hürthle Cell Neoplasm and Risk of Malignancy

Postoperative Findings of the Cytological Diagnosis of Follicular Neoplasm or Hurthle Cell Neoplasm and Risk of Malignancy Jung Uee Lee, Minho Shong Department of Pathology, Daejeon St. Mary’s Hospital, The Catholic University of Korea, Daejeon; Research Center for Endocrine and Metabolic Diseases, Division of Endocrinology, Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, Korea Endocrinol Metab 25(4):298-300, December 2010 DOI: 10.3803/EnM.2010.25.4.298 EDITORIAL

Postoperative Findings of the Cytological Diagnosis of Follicular Neoplasm or Hürthle Cell Neoplasm and the Risk of Malignancy

Background: Follicular neoplasm (FN) or Hurthle cell neoplasm (HN) is a less well understood pitfall when evaluating thyroid nodule with fine-needle aspiration (FNA). This study aimed to determine the rates of malignancy and the predictive factors for malignancy in thyroid nodules with a cytological diagnosis of FN or HN. Methods: The patients who were cytologically diagnosed as having FN or HN after FNA between 1995 and 2004 at Asan Medical Center were included in this study. We collected the pathology data until 2009 and we analyzed the clinical characteristics associated with malignancy. Results: A total 478 patients were cytologically diagnosed as having FN or HN during the study period and 327 (68%) among them underwent thyroid surgery. Thyroid malignancy was confirmed in 157 (48%) of 327 patients. Malignancy was confirmed in 124 patients with FN (124/253, 49%). They were 48 papillary, 65 follicular, 7 Hurthle cell and 3 medullary carcinomas and 1 anaplastic carcinoma. The malignancy in the cases of HN (33/71, 44.6%) was 9 papillary, 4 follicular and 20 Hurthle cell carcinomas. The risk of malignancy was not associated with male gender, a larger tumor size (> 4 cm) or the diagnosis of HN. However, an age below 20 years (RR 3.6, P = 0.03) and above 60 years (RR 2.3, P = 0.04) was associated with an increased risk of malignancy. Conclusion: About half of the patients with FN or HN on FNA cytology were diagnosed as having thyroid cancer after surgery. The malignancy rate for the cytologic diagnosis of HN was similar to that for FN. Thyroid surgery should be recommended for this situation, and especially for patients younger than 20 years or older than 60 years.

Hemithyroidectomy: The Optimal Initial Surgical Approach for Individuals Undergoing Surgery for a Cytological Diagnosis of Follicular Neoplasm

The primary objective of this study was to determine the true proportion and optimal surgical approach for individuals undergoing thyroid operation for a suspicion of cancer based on a fine-needle aspiration biopsy diagnosis of a follicular neoplasm (FN). A secondary objective of this study was to determine whether patient characteristics could assist the clinician in predicting malignancy in this FN patient cohort. A retrospective chart, pathology, and cytology review of 370 consecutive primary thyroid operations was performed over a 4-year period at a tertiary care referral center. Clinical patient data were evaluated as an adjunct for predicting malignancy in the FN patient cohort. Univariate and multivariate analyses were used to investigate the association and the predictability. A total of 80 (22%) of the 370 patients underwent hemithyroidectomy to rule out cancer based on clinical presentation with a fine-needle aspiration biopsy diagnosis of FN. Fifteen (19%) of the FN cases were diagnosed as cancer by histological analysis (4 follicular carcinomas and 11 papillary carcinomas). Hemithyroidectomy was considered adequate treatment for 77 patients (96%). No patient characteristic significantly predicted the presence of cancer by either univariate or multivariate analysis. Overall, in the FN patient population, five hemithyroidectomies were performed to identify each cancer, and no further operation was required in 96% of patients. New diagnostic tools are needed to reduce the number of operations performed for benign pathology in patients with nodular thyroid disease and a needle biopsy diagnosis of FN.

Completion thyroidectomy in patients with thyroid cancer who initially underwent unilateral operation.

In some instances, thyroid cancer may be diagnosed with histological examination after resection of putative or suspected benign nodule. In these cases, completion thyroidectomy followed by radioiodine ablation is usually recommended to prevent recurrence. If small intrathyroidal cancer is found, completion thyroidectomy may not be performed. Many patients have separate cancers in the contralateral lobe and in these cases completion thyroidectomy is essential even though primary tumour is small and limited within thyroid. We analysed the frequency of malignant lesions in the contralateral lobe after completion thyroidectomy and assessed the predictive factors that may anticipate the presence of malignant lesion that may necessitate completion thyroidectomy. Between 1995 and 2001, 243 patients were operated under the cytological diagnosis of follicular neoplasm. A total of 214 of them underwent lobectomy and isthmectomy and 81 turned out to have malignant disease in the resected lobe and they underwent completion thyroidectomy within a week to 6 months after the permanent section diagnosis of cancer. Their mean age was 40.7 +/- 12.1 years (range 14-71 years). After initial surgery, 53 patients had follicular carcinoma, 24 papillary carcinoma, one Hürthle cell carcinoma, one medullary, one insular and one anaplastic carcinoma. Mean tumour size was 4.1 +/- 2.6 cm (range 0.9-11 cm). After completion thyroidectomy, factors predicting the presence of cancer in the contralateral lobe were assessed according to clinical parameters and pathologic findings in ipsilateral lobe. First surgery revealed cancer multifocality in 34 cases, perithyroidal tumour extension in six and regional lymph node metastases in three. After completion thyroidectomy, 29 of the 81 patients revealed additional cancer in the contralateral lobe. Age, sex, size or pathologic type of the primary tumour was not associated with the presence of additional tumour in the contralateral lobe. Cancer multifocality in the ipsilateral lobe was the only significant variable to predict the presence of additional cancer in the contralateral lobe (relative risk = 6.03, confidence interval 2.23-16.35). Coexistence of benign nodule in ipsilateral lobe was not associated with increased cancer risk in the contralateral lobe. When diagnosed as thyroid cancer after unilateral surgery, the only predictive factor for the presence of additional contralateral cancer was multifocality of cancer in the ipsilateral lobe. We suggest that completion thyroidectomy is mandatory if multifocal cancers are found in the resected lobe, even though the cancers are very small and limited within the thyroid.

Ultrasonography-guided fine-needle aspiration of thyroid incidentaloma: correlation with pathological findings.

There are many reports that diagnostic accuracy of fine-needle aspiration (FNA) of thyroid is improved with ultrasound guidance, especially for impalpable nodules. Despite its general acceptance, routine use of ultrasound-guided fine-needle aspiration (USGFNA) has been the source of much controversy due to the lack of large-scale studies and lack of data on the natural course of well-differentiated thyroid cancer of small size. The aim of our study was to define the rate of malignancy in relatively large numbers of patients with incidentally detected impalpable thyroid nodules and to assess the extent of disease in patients with suspicious or malignant cytology on USGFNA of thyroid nodules by surgery. We retrospectively reviewed the medical records of the 267 patients who underwent USGFNA of incidental thyroid nodules from January 2000 to December 2001. Three hundred and seventeen nodules from 267 patients were aspirated. The average size of nodules was 0.9 +/- 0.3 cm, a range of 0.2 cm to 1.5 cm. All 317 lesions were impalpable. Cytological diagnosis included 101 inadequate specimen (32%), 139 benign (44%), 29 indeterminate (9%), four suspicious of follicular or Hürthle cell neoplasm (1%), 42 papillary carcinoma (13%) and two others. The size of the nodule was not related to the probability of getting an adequate specimen for cytological diagnosis. Forty of 48 patients with suspicious or malignant cytology underwent surgery. All 35 patients with a cytological diagnosis of papillary carcinoma were confirmed to have papillary carcinoma on histological results. One of three patients with a cytological diagnosis of follicular neoplasm had a follicular carcinoma. In 36 patients with well-differentiated thyroid cancer, extrathyroidal extension was observed in 44% (16/36), regional lymph node metastasis was found in 50% (18/36) and multifocal tumours were found in 39% (14/36). The rate of malignancy in incidentally detected impalpable thyroid nodules was 12% in retrospective analysis of our patients. In this subgroup, 69% (25/36) of patients had either extrathyroidal extension or regional node involvement and 39% had multifocal tumours at surgery. This suggests that the small size alone does not guarantee low risk in incidentally found thyroid cancers. USGFNA is a useful diagnostic method in these patients.

Postoperative findings and risk for malignancy in thyroid nodules with cytological diagnosis of the so-called "follicular neoplasm".

Background :Malignant follicular lesion is not differentiated from benign lesions cytologically. The objective of this study was to assess the rate and the risk of malignancy in thyroid nodules which were cytologically diagnosed as follicular neoplasm by fine-needle aspiration (FNA) cytology.Methods :All the patients who had undergone surgery with cytological diagnosis of follicular neoplasm from January 1996 through December 2001 in Asan Medical Center were studied retrospectively. Patients’ and nodule characteristics were analyzed for factors associated with the presence of cancer. Two hundred and fifteen patients (196 females, 19 males) were included and their mean age was 39.4 years (range: 12–76).Results :About half of the patients (102 out of 215, 47.4%) had malignancy with 29 papillary carcinomas, 57 follicular carcinomas, 15 Hürthle cell carcinomas and 1 medullary carcinoma. Previously suggested factors associated with risk for malignancy, such as male gender, large tumor size (>4 cm) or age of patients (>45 years), were not associated with increased risk. Diagnosis of Hürthle cell neoplasia on FNA was also not associated with increased risk. Only the extremes in age of the patients (below 20 or above 60 years) were associated with increased risk for malignancy.Conclusion :In our findings, prevalence of carcinoma in thyroid nodule patients with cytological diagnosis of follicular neoplasm was much higher than those reported. Clinical characteristics, such as male gender, age and nodule size, are not useful predictors for the presence of malignancy. Thyroid nodules with cytological diagnosis of follicular neoplasm warrant immediate surgery.