Ultrasound-guided fine-needle aspiration biopsy of the thyroid

Rapid on-site evaluation (ROSE) for fine needle aspiration of thyroid: benefits, challenges and innovative solutions

Rapid on-site evaluation/adequacy assessment (ROSE) is considered an essential component of thyroid fine needle aspiration (FNA) and many reported that it significantly decreases the nondiagnostic (ND) rate. The average reported ND rate without ROSE is about 20% and is improved by 12% when ROSE is implemented. However, the data also suggest that the improvement in ND rate after implementation of ROSE is directly related to the ND rate prior to ROSE and that it is mostly beneficial to aspirators with less experience. Several studies have also raised concerns regarding the impact of ROSE as it prolongs the procedure time, requires additional resources and increases the cost incurred by the additional fees. This resulted in a wide variation in the methodology applied to acquire the sample and implement ROSE across the globe with variation in the number of passes performed, stain utilized and the personnel reviewing the slides, e.g., cytotechnologists versus pathologist. This review summarized the literature reporting the impact of ROSE including its pros and cons, its accuracy and reproducibility, concordance between cytotechnologists and pathologists based on final diagnosis and highlights the different ways laboratories attempted to circumvent the challenges. In particular, the review highlights a unique approach practiced in Ito Hospital, Tokyo, Japan.

Usefulness of Ultrasound-Guided Fine-Needle Aspiration Cytology in the Diagnosis of Non-Palpable Small Thyroid Nodules

Aims and background

Diverse and contradictory approaches have been suggested for the management of non-palpable thyroid nodules. The aim of our study was to evaluate the indications and limits of ultrasound-guided fine-needle aspiration cytology (US-FNAC) in non-palpable infracentimetric thyroid nodules.

Methods and study design

From September 2003 to December 2004 we observed 325 patients with non-palpable thyroid nodules. We divided our series into three groups according to the diameter of the lesion in order to verify the effectiveness of US-FNAC for lesions of less than 1 cm.

Results

We assessed the cases with satisfactory and unsatisfactory results in the three groups into which the sample was divided (4 mm to 1 cm; 10.1 mm to 15 mm, and 15.1 mm to 25.5 mm). Our statistical analysis by means of the z-test showed there was no significant (5%) difference in the percentage distribution of the unsatisfactory results in the three groups.

Conclusions

Fine-needle cytology appears to be a useful diagnostic tool also for nodules of less than one cm because the percentage of unsatisfactory results is not related to the size of the nodule.

Comparison of 1869 thyroid ultrasound-guided fine-needle aspiration biopsies between general surgeons and interventional radiologists

BACKGROUND

Thyroid nodules are commonly encountered problems in clinical practice. For patients who have a thyroid nodule, the fine-needle aspiration biopsy (FNAB) is the most important test, as it is the most reliable diagnostic method for distinguishing between benign thyroid nodules and cancerous nodules. FNAB is able to be performed either via an ultrasound (USG) or alone and is the first choice when it comes to diagnosing thyroid nodules, given that it is cheap, safe and provides accurate results.

OBJECTIVE

In this study-a retrospective analysis of FNAB via USG - our aim is to evaluate the multiple variables related to FNAB procedures, including the experience of the person performing the biopsy, the age and gender of the patient, the number of nodules, the size of the nodule(s) and the number of lams recorded from the cytopathology report on non-diagnostic rates, conducted at an invasive radiology clinic and at a general surgery clinic.

MATERIALS AND METHODS

A total of 1062 patients involving 1869 nodules, examined using FNAB via USG, were reviewed retrospectively from records dated between November 2011 and July 2014 and from pathology reports taken from the ANEAH General Surgery clinic and Interventional Radiology clinic. Cytopathology results were classified according to the 2007 Bethesda System for Reporting. Gender, age, number of nodules, diameter of the nodules, biopsied nodules, location of the nodules, number of lams, symptoms and the date of biopsies were the parameters used to examine the factors involved in non-diagnostic cytopathology invasive radiology. These parameters were inspected at both of the clinics (ANEAH General Surgery clinic and Interventional Radiology clinic). In analyzing the results, the statistical significance level was set at 0.05, where in cases that the p value was under 0.05 (p < 0.05), it was determined that no significant relationship existed. In this study, data were analyzed using SPSS 20 software.

RESULTS

Of the nodules reviewed, 1620 were found on females and 249 on males. The age of the patients ranged from 10 to 87 years, with the mean age being 50 years. In the general surgery clinic, 470 nodules of 341 patients were aspirated, and in the interventional radiological clinic, 1399 nodules of 721 patients were aspirated. In the literature review conducted to compare statistical assessments of FNAB via USG, no significant difference was found between the ANEAH General Surgery clinic and the Invasive Radiology clinic (p > 0.05). In the invasive radiology clinic, non-diagnostic rates decreased with the increase in experience of the person who conducted the biopsy (p = 0.001).

CONCLUSION

The results from both of the clinic's rates of non-diagnostic FNAB, performed via USG, were found to be acceptable. Our study also demonstrates that USG-guided FNAB can be performed with a low non-diagnostic rate as experience grows.

Parathyroid Adenoma Completely Impacted within the Thyroid Gland: A Case Report

Ectopic parathyroid adenoma can be seen in various locations. Sometimes ultrasound and even fine needle aspiration studies cannot distinguish this lesion from thyroid lesions. A 29-year-old woman with a prominent nodule of left thyroid lobe was referred to surgical department. Thyroid function test were normal. She had no family history of parathyroid disease, other endocrine disease, and any other malignancies and had received no radiation. Ultrasonography revealed a solid and hypoechoic mass, 25x20 mm in size, with a regular shape and contour without calcification in the inferior of left lobe of the thyroid gland. For definite diagnosis, immunohistochemistry study of the lesion with three markers was done. Finally, PTH marker was positive in cytoplasms of cells so parathyroid adenoma was confirmed. Fine needle aspiration of the nodule was suspicious for follicular neoplasm; however, postoperative histopathology and immunohistochemistry revealed a parathyroid adenoma. Ultrasonography may be helpful to identify localized thyroid lesions especially in parathyroid adenoma.

A systematic review of ultrasound-guided FNA of lesions in the head and neck--focusing on operator, sample inadequacy and presence of on-spot cytology service

The objective of this review is to perform a systematic review of ultrasound-guided fine-needle aspiration (FNA) services for head and neck lesions with assessment of inadequacy rates and related variables such as the presence of immediate cytological assessment. A computer-based systematic search of articles in English language was performed using MEDLINE (1950 to date) from National Health Service evidence healthcare database and PubMed. Full texts of all relevant articles were obtained and scrutinized independently by two authors according to the stated inclusion and exclusion criteria. The primary search identified 932 articles, but only 78 met all the study criteria. The overall inadequacy rate was 9.3%, 16 studies had on-site evaluation by a cytopathologist/specialist clinician with a rate of 6.0%. In seven studies, a cytotechnician was available to either assess the sample or prepare the slides with an average inadequacy rate of 11.4%. In 1 study, the assessment was unclear, but the inadequacy rate for the remaining 54 studies, without immediate assessment, was 10.3%. The rate for the cytopathologist/specialist clinicians was significantly different to no on-site assessment but this was not found for assessment by cytotechnicians. The review suggests that the best results are obtained with a cytopathologist-led FNA service, where the pathologist reviews the specimen immediately, in relation to the clinical context, thereby deciding on adequacy and need for further biopsies. A systematic review looking at ultrasound-guided FNA of head and neck lesions has not been published previously.

Investigation of factors potentially influencing calcitonin levels in the screening and follow-up for medullary thyroid carcinoma: a cautionary note

BACKGROUND

The malignant transformation of thyroid C cells is associated with an increase in human calcitonin (hCT), which can thus be helpful in the early diagnosis of medullary thyroid carcinoma (MTC). For this reason, hCT levels should be determined in all patients with nodular goitre. Hashimoto's thyroiditis, nodular goitre and proton pump inhibitor (PPI) therapy are factors reported to influence basal serum hCT concentrations. The diagnostic role of mildly to moderately increased hCT levels is thus a matter of debate. In this study, we attempt to clarify the role of the aforementioned factors.

METHODS

From 2008 to 2009, we collected data from 493 patients who were divided into five groups. We assessed whether there were significant differences in hCT levels between patients with Hashimoto's thyroiditis, patients with nodular goitre, patients with PPI therapy, and healthy control subjects. In addition, we investigated whether a delayed analysis of blood samples has an effect on serum hCT concentrations.

RESULTS

Immunoradiometric assays (Calcitonin IRMA magnum, MEDIPAN) revealed that the time of analysis did not play a role when low levels were measured. Delayed analysis, however, carried the risk of false low results when serum hCT concentrations were elevated. Men had significantly higher serum hCT levels than women. The serum hCT concentrations of patients with Hashimoto's thyroiditis and nodular goitre were not significantly different from those of control subjects. Likewise, PPI therapy did not lead to a significant increase in serum hCT concentrations regardless of the presence or absence of nodular goitre.

CONCLUSIONS

Increases in serum hCT levels are not necessarily attributable to Hashimoto's thyroiditis, nodular goitre or the regular use of PPIs and always require further diagnostic attention.

Correlation between sonography and antibody activity in patients with Hashimoto thyroiditis

OBJECTIVES

Patients with Hashimoto thyroiditis show structural changes of the thyroid that can be identified by a variety of sonographic criteria. We conducted this study to investigate whether there is a correlation between sonography and antibody activity and to assess the role of sonography in the diagnosis and follow-up of Hashimoto thyroiditis. In addition, we present a new classification system (termed the VESINC system [volume, echogenicity, sonographic texture, pseudonodular hypoechoic infiltration, nodules, and cysts]), which helps improve the clarity of sonographic findings.

METHODS

The study included 223 consecutive patients with previously diagnosed Hashimoto autoimmune thyroiditis who attended the thyroid clinic of the German Armed Forces Central Hospital in Koblenz for follow-up examinations between 2006 and 2008. Laboratory tests were performed to measure the levels of free triiodothyronine, free thyroxine, thyrotropin, anti-thyroglobulin antibodies (TgAbs), and antithyroid peroxidase antibodies (TPOAbs). Sonography was performed according to a strict protocol. We then assessed whether a correlation existed between antibody activity and the 6 sonographic variables of the VESINC system.

RESULTS

Hypoechogenicity, heterogeneity, and pseudonodular hypoechoic infiltration were associated with significantly higher TPOAb activity (P < .001). There were no significant correlations between the other sonographic variables examined (cysts, nodules, and volume) or the biometric data with the TPOAb and TgAb levels. In addition, an assessment of TgAb levels did not show significant differences in correlations with any of the sonographic variables.

CONCLUSIONS

Sonography is a noninvasive diagnostic imaging modality that provides information about the level of inflammatory activity. Markedly decreased echogenicity, heterogeneity, and multifocal pseudoinodular hypoechoic infiltration are indicative of a high level of inflammatory activity. The sonographic classification system presented here (VESINC system) can be a useful tool for comparing sonographic findings in a rapid and objective manner during follow-up of Hashimoto thyroiditis.

On-site adequacy evaluations performed by cytotechnologists: correlation with final interpretations of 5241 image-guided fine-needle aspiration biopsies

BACKGROUND

Practice patterns regarding on-site assessment of the adequacy of image-guided fine-needle aspiration biopsies (FNABs) vary among laboratories, but in many laboratories primary responsibility rests with the cytotechnologists. On-site evaluation provides feedback on the need for additional passes and facilitates triaging of the specimen for time-sensitive ancillary studies. Prior studies have suggested that cytotechnologists can assess the initially obtained specimens correctly, but they are few in number and limited by small size. The purpose of this study was to assess the frequency with which our cytotechnologists were able to correctly assess specimens as adequate using a large-scale database that included a wide range of image-guided FNABs.

METHODS

The frequency that on-site adequacy assessments of 5241 image-guided FNABs were correct was determined by correlating the cytotechnologists' assessments of adequacy with the final cytologic interpretation. An adequacy assessment was considered correct if the FNAB was ultimately reported as satisfactory and unequivocally benign or malignant. An adequate reading on a case that was ultimately reported as unsatisfactory, atypical, or suspicious was deemed "incorrect." The effect of imaging modality was also analyzed.

RESULTS

Of 5241 FNABs, 2784 (53%) were interpreted as adequate on site. Of these, 2637 (95%) were correctly considered adequate. Of the common biopsy sites sampled, the adequacy assessments for liver FNABs demonstrated the highest frequency for being correctly considered adequate (97%) and those for kidney FNABs showed the lowest (90%). Imaging modality had no effect on accuracy.

CONCLUSIONS

Cytotechnologists are almost always correct when assessing initial FNAB samples as adequate.

Increased annual frequency of Hashimoto's thyroiditis between years 1988 and 2007 at a cytological unit of Sicily

Like other auto-immune diseases, Hashimoto's thyroiditis (HT) results from the interaction of genetic with environmental factors. Only few studies have evaluated the year-to-year change in frequency of HT over a wide period of time. The endocrine division of our Hospital has reported a great increase in the annual frequency of HT between 1975 and 2005, and a progressive decrease in both age at presentation and female to male (F/M) ratio starting in the mid-1990s. Between years 1988 and 2007, we have collected 8397 adequate examinations by fine needle aspiration cytology (FNAC) on 8397 persons referred for the evaluation of a solitary or dominant thyroid nodule (total FNAC and persons=8520) with a 14-fold increase in 2007 over 1988. In this 20-year period, cases of HT, De Quervain's thyroiditis (DQT) and Riedel's thyroiditis (RT) were 490, 36 and two, respectively. HT cases were one in 1988 but 90 in 2007, with a significant upward temporal trend (r=0.919, P<0.001) and significant downward trend for age at FNAC (r=-0.466, P<0.05). In contrast, DQT cases were zero and one, respectively, with no significant temporal trend (r=0.29, P=0.21). The HT increase in frequency started in 1996 (+350% over 1995). Until 1995 there was only one man, but there were 22 men in 2005-2007. These FNAC data provide independent confirmation to the data from the endocrine division of the same hospital, further supporting the conclusion that only environmental modifications can explain these marked changes that have occurred in such a relatively short period of time.

Thyroid bed fine-needle aspiration: experience at a large tertiary care center

Fine-needle aspiration (FNA) of thyroid bed (TB) lesions is a common diagnostic modality in monitoring patients for recurrent cancer after a thyroidectomy. To elucidate the value of TB FNA, we reviewed our experience at The Johns Hopkins Hospital, Baltimore, MD. We identified 57 TB FNA specimens from 50 patients. Of the patients, 36 were being followed up for papillary carcinoma, 7 for medullary carcinoma, 4 for follicular carcinoma (1 also had papillary carcinoma), and 1 for poorly differentiated neuroendocrine carcinoma; 3 had previous benign diagnoses. TB FNA yielded diagnostic material in 49 of 57 cases. Of 37 malignant or atypical FNA samples, 32 had surgical follow-up; 30 of 32 were confirmed malignant. The FNA result was benign in 12 of 57, including 6 cases of benign thyroid and 1 case of parathyroid tissue. Immunohistochemical staining was contributory in 5 of 57 cases. TB FNA is a highly reliable tool for diagnosing recurrent thyroid carcinoma. Residual benign thyroid and parathyroid tissue are potential pitfalls; awareness of these and judicious use of immunohistochemical staining can prevent misdiagnoses.

Fine-needle aspiration of follicular adenoma versus parathyroid adenoma: the utility of multispectral imaging in differentiating lesions with subtle cytomorphologic differences

BACKGROUND

Multispectral image analysis is an emerging tool that utilizes both spatial and spectral image information to classify images that can be used for the differentiation between benign versus malignant cells. The aim of the current study was to analyze the ability of this tool in differentiating subtle cytologic differences that cannot be appreciated by the human eye. Herein, the authors used fine-needle aspirations (FNAs) of follicular adenoma (FA) and parathyroid adenoma (PA) as a test case.

METHODS

The Nuance platform was used to collect image stacks that were subsequently analyzed with CRI-MLS software, a neural network-based artificial intelligence system that can classify images using automatically "learned" spatial-spectral features. CRI-MLS was trained on random, well-preserved FA cells and PA cells from the training set (n = 45 cells each). An algorithmic solution was developed and then validated on an independent series comprised of 1904 FA cells from 5 FA cases and 690 PA cells from 5 PA cases.

RESULTS

The solution from the CRI-MLS classifier showed 1876 FA cells (98.5%) as true FA and 28 FA cells (1.5%) as false PA, whereas 663 PA cells (96%) were true PA and 27 PA cells (4%) were false FA. The summary result of this solution was a sensitivity of 98.5%, a specificity of 96.1%, and a positive predictive value of 98.6%.

CONCLUSIONS

The best spatial-spectral imaging solution was able to correctly classify 2534 of 2594 cells (98%) and misclassified only 55 of 2594 cells (2%). These data suggest that this technology may be valuable in a clinical setting to help differentiate and classify morphologically similar lesions.

Specimen adequacy and diagnostic specificity of ultrasound-guided fine needle aspirations of nonpalpable thyroid nodules

Ultrasound-guided fine needle aspiration (USG-FNA) is a safe, effective, and dependable test used to assess thyroid nodules. However, the size of the lesion can adversely affect the outcome of the procedure. The aim of this study was to assess specimen adequacy and diagnostic specificity in USG-FNA of thyroid nodules measuring < or = 1.5 cm. A total of 219 thyroid FNAs were performed in a one year; 26 were obtained by pathologists, 139 by clinicians, and 54 by radiologists under ultrasound guidance. Of the 54 ultrasound-guided aspirates, 19 cases (35%) were performed on nodules < or = 1.5 cm (range 0.8-1.5 cm, mean 1.3 cm). Cytologic material from these 19 cases was reviewed along with corresponding available follow-up surgical material. Standard criteria for specimen adequacy and established morphologic criteria for diagnostic specificity were assessed in each case. All 19 cases met criteria for specimen adequacy, and in 17 cases (89%) specific cytologic diagnoses were made (cellular/adenomatous nodule--2 cases, colloid nodule--10 cases, Hashimoto's thyroiditis--4 cases, and papillary cystic carcinoma--1 case). The diagnoses were confirmed by surgical follow-up in six cases including the case of papillary carcinoma. One case diagnosed as suspicious for a papillary carcinoma subsequently was found to be a follicular adenoma by histology. In one case, a diagnosis of lymphocytic thyroiditis versus intrathyroidal lymphoid tissue was made (See Table I). In majority of cases of USG-FNA of nonpalpable thyroid nodules, adequate material may be obtained for a specific cytopathologic diagnosis.

Ultrasound of thyroid cancer

The management of thyroid nodules is multi-disciplinary and involves head and neck surgeons, pathologists and radiologists. Ultrasound is easy to perform, widely available, does not involve ionizing radiation and is readily combined with fine needle aspiration cytology (FNAC). It is therefore an ideal investigation of choice for evaluating thyroid nodules. It evaluates specific features that help in identifying the nature of the nodule and FNAC helps in diagnostic accuracy. In addition, following treatment for thyroid cancer ultrasound provides a safe tool for disease surveillance. This paper discusses the role of ultrasound in the management of patients with thyroid cancer.

Thyroid cancer in the thyroid nodules evaluated by ultrasonography and fine-needle aspiration cytology

Thyroid nodule is common disorder in endocrine clinics. In Taiwan, thyroid ultrasonography with fine-needle aspiration cytology (FNAC) is the first-line examination procedure. Data in large series on the incidence of thyroid malignancy presenting with thyroid nodules are lacking in this area. To determine the incidence of malignancy in thyroid nodules and compare the results with other populations, this investigation retrospectively reviewed 21,748 subjects who were examined in one medical center from January 1986 to December 1999. All patients underwent thyroid ultrasonography studies using a real-time ultrasonographic machine and a 10-MHz transducer. Fine-needle aspirations were made in the suspected thyroid nodule and stained using the Romanowsky- based method developed by Liu. By the end of 2002, some 3629 patients (16.7%) had thyroid nodules after surgical treatment. This group comprised 3011 women with a mean age of 41.5 +/- 13.9 years, and 618 men with a mean age of 45.7 +/- 14.9 years. Of patients undergoing surgical treatment, 2761 (76.1%) patients were diagnosed with benign nodules, 858 (23.6%) with malignant nodules, and 10 (0.3%) with atypical adenoma (7 follicular and 3 Hürthle cells). The percentages of thyroid malignancy in each age group revealed two peaks in both genders, namely in patients aged 20 to 29 years and in elderly patients (aged over 65 years). The peak age for thyroid malignancy in both genders was 41 to 60 years (male) and 21 to 40 years (female). The highest ratio of malignancy occurred in the elderly group (37.2%) receiving surgical treatment. In young patients (below 19 years) the percentage of malignancy was no greater than for the whole age group (20.2% versus 25.6%). Anaplastic and metastatic cancers affecting the thyroid were the main subjects in the age group. The present results demonstrated a younger distribution for well-differentiated thyroid cancer, particularly papillary thyroid carcinoma, compared to previous studies. This outcome may have resulted from the routine application of ultrasonography with FNAC in assessing the thyroid nodules, possibly helping to achieve more timely detection. The incidence of thyroid malignancy in young patients was no higher than in adults. Early detection of thyroid malignancy may be the main reason for this phenomenon. Male subjects with thyroid nodules displayed a higher incidence of this malignancy than females. Aging subjects with thyroid nodules suffered a higher rate of malignancy and were poorly differentiated. In conclusion, this retrospective large-series study demonstrated that 3.9% (858/21,748 cases) of patients with thyroid nodules showed histopathologically proven malignancy. Thyroid cancer detected by ultrasonography with FNAC occurred an average of 10 years younger than in prior studies.

Fine-needle aspiration of the thyroid: an overview

Thyroid nodules (TN) are a common clinical problem. Fine needle aspiration (FNA) of the thyroid now is practiced worldwide and proves to be the most economical and reliable diagnostic procedure to identify TNs that need surgical excision and TNs that can be managed conservatively. The key for the success of thyroid FNA consists of an adequate or representative cell sample and the expertise in thyroid cytology. The FNA cytologic manifestations of TNs may be classified into seven working cytodiagnostic groups consisting of a few heterogenous lesions each to facilitate the differential diagnosis. Recent application of diagnostic molecular techniques to aspirated thyroid cells proved to be useful in separating benign from malignant TNs in several cases of indeterminate lesions.

Reporting thyroid fine-needle aspiration: Literature review and a proposal

Reporting schemes for thyroid fine-needle aspirations in the literature were reviewed and classified according to the number of categories in the scheme and the significance of each category. The sensitivity, specificity, and positive predictive and negative values were determined for each scheme, if possible. A reporting scheme based on the probability of finding carcinoma on histology is proposed.

Ultrasound-Guided Biopsies: Tricks, Needle Tips, and Other Fine Points

Ultrasound (US)-guided biopsy of thyroid nodules, abdominal masses, liver masses, random core liver biopsies, as well as aspiration of abdominal or pleural fluid is now routine practice. The ability of US to guide biopsy of abnormalities seen on cross-sectional imaging studies is well recognized as an efficient and effective means of achieving a tissue diagnosis. Its use requires basic knowledge of US image analysis, but clinically useful intuitive and nonintuitive methods can enhance its strengths. The purpose of this review is to provide a practical guide to some of these tricks that may be useful in everyday clinical practice.

Cytological correlation in patients who have a pre-diagnosis of thyroiditis ultrasonographically

OBJECTIVE

Radiological-cytopathological correlation in patients who are prediagnosed ultrasonographically as thyroiditis.

STUDY DESIGN

Fourty five patients with hypoechogenic, heterogeneous, and/or pseudolobulated thyroid gland sonographically were included in this prospective study. Except for the patients with subacute thyroiditis, none of the patients had a prediagnosis of thyroiditis clinically. All patients were evaluated for their thyroid gland functions and intraglandular vascularity and ultrasonography-guided fine needle aspiration biopsy (US-FNAB) was performed.

RESULTS

The diagnosis of thyroiditis was confirmed in 36 patients (16 lymphocytic thyroiditis, 20 Hashimoto thyroiditis, two subacute granulomatous thyroiditis) in sonographically suspected patients. In six patients, FNAB was thyroiditis negative. The true diagnosis ratio of thyroiditis was increased up to 81.8% (%95 Confidence Interval: 0.70-0.92) by performing US-FNAB, while it was 4.5% with only clinical and laboratory findings (p=0.0001).

CONCLUSION

Hypoechogenic, heterogeneous thyroid gland may be strongly related to thyroiditis, which does not have any specific radiological findings. The sonographic finding of generalized parenchymal abnormality should alert the clinician to consider diffuse thyroid disease as the underlying cause and FNAB should be performed and a follow-up examination of these patients must be continued due to the risk of neoplastic disease of thyroid.

Clinical relevance of non-palpable thyroid nodules as assessed by ultrasound-guided fine needle aspiration biopsy

It is known from autopsy data that thyroid nodules are far more common than can be detected by palpation alone. With the wide use of modern non-invasive imaging many non-palpable thyroid nodules are discovered but the proper approach to these nodules is still debatable. In a retrospective study, we reviewed the data from 186 US-guided FNA biopsies (US-FNAB) performed between May 1995 and March 1997 at the Sapir Medical Center, Israel, a iodine-sufficient urban area. Sixty-one of the 186 US-FNAB of the thyroid were performed in non-palpable nodules. The mean size of these nodules was 2.4 +/- 1.0 cm (mean +/- SD) ranging from 1.1-5.5 cm. Description of the nodule consistency was available in 53 cases; 42/53 were solid and 11/53 were solid-cystic. FNAB was diagnostic in 46 patients and non-diagnostic in 15. Forty-three of the diagnostic cytology reports were benign, one revealed papillary carcinoma, one had suspicious findings and the third was suspicious for a follicular neoplasm. The last two patients were referred to surgery and a follicular adenoma was found in both. Among the 61 non-palpable thyroid nodules, only one was papillary carcinoma, a prevalence of 1.6%. The other two patients referred to surgery had benign lesions. We found a low prevalence of malignancy in relatively large non-palpable thyroid nodules.

Influence of ceramide metabolism on P-glycoprotein function in immature acute myeloid leukemia KG1a cells

Previous studies have emphasized the role of glucosylceramide (Glu-Cer) synthase in multidrug resistance (MDR) regulation. However, the mechanism by which the inhibition of this enzyme results in increased drug retention and cytotoxicity remains unclear. In this study, we investigated the respective role of ceramide (Cer) accumulation and Glu-Cer derivatives depletion in MDR reversal effect of 1-phenyl-2-decanoylamino-3-morpholino-1-propanolol (PDMP), a Glu-Cer synthase inhibitor. We show here that treatment with PDMP resulted in increased rhodamine 123 (Rh123) retention and potent chemosensitization of P-glycoprotein (P-gp)-expressing cells, including KG1a cells, KG1a/200 cells, K562/138 cells, and K562/mdr-1 cells. Metabolic studies revealed that PDMP induced not only time-dependent Cer accumulation but also reduction of all glycosylated forms of Cer, including Glu-Cer, lactosylceramide (Lac-Cer), monosialo ganglioside (GM3) and disialo ganglioside (GD3). The influence of these metabolites on P-gp function was investigated by measuring Rh123 retention in PDMP-treated cells. P-gp function was found to be stimulated only by the addition of gangliosides in all resistant cell lines, whereas Glu-Cer, Lac-Cer, and Cer had no effect. Moreover, in KG1a/200 cells, GD3 and, to a lesser extent, GM3 were found to phosphorylate P-gp on serine residues. Altogether, these results suggest that, at least in leukemic cells, gangliosides depletion accounts for PDMP-mediated MDR reversal effect, and that gangliosides are important P-gp regulators perhaps through their capacity to modulate P-gp phosphorylation.

Fine-needle aspiration biopsy of the thyroid: comparison between thyroid palpation and ultrasonography

OBJECTIVE

To describe our experience with fine-needle aspiration biopsy (FNAB) of the thyroid and compare our results with direct palpation versus ultrasound scanning (USS) in an area of endemic goiter in Italy.

METHODS

We considered all patients submitted to ultrasound-guided FNAB of thyroid nodules during a 10-month period at our outpatient clinic and analyzed the following: (1) clinical data (number of nodules and identification of the nodule for FNAB); (2) USS data (number of nodules and identification of the nodule for FNAB on the basis of hypoechoic pattern + blurred perinodal halo + microcalcifications or intranodal color Doppler signal indicative of blood flow); (3) cytologic specimens, categorized as suspicious, malignant, negative, or nondiagnostic; and (4) histologic final report of the cytologically positive nodules.

RESULTS

The study group consisted of 348 female and 72 male patients who underwent FNAB of the thyroid at our institution. Among the 140 patients with no palpable thyroid nodules, USS showed that 106 had a single nodule and 34 had multinodular goiters. Among the 182 patients with a single palpable thyroid nodule, USS revealed that 138 had a single nodule, 42 had a multinodular goiter, and 2 had lobe enlargement without detectable nodules. All 98 patients with multinodular palpable goiter had a similar pattern on USS. Of the 420 cytologic specimens, 46(11.0%) were positive for thyroid cancer, 313 (74.5%)were negative, and 61 (14.5%) were nondiagnostic. Histologic malignant growth was confirmed in 27 cytologically positive nodules. Of these histologically malignant nodules, 12 (45%) were nonpalpable, 9 (33%) were single palpable nodules, and 6 (22%) were from a nodule with a suspicious ultrasound pattern within a multinodular goiter.

CONCLUSION

Manually guided FNAB is not feasible in nonpalpable nodules and not accurate in a multinodular goiter. Both situations are clinical challenges, and USS should be performed for accurate FNAB under these circumstances. Because 52% of histologically malignant nodules in our study were found only with the aid of ultrasound-guided FNAB, this procedure should be used where multinodular goiter is endemic. Our overall rate of nondiagnostic specimens was comparable to that reported in the literature.

Ultrasound-guided fine-needle aspiration of the thyroid assessed by Ultrafast Papanicolaou stain: data from 1135 biopsies with a two- to six-year follow-up

One of the limitations of fine-needle aspiration (FNA) of the thyroid is difficulty in distinguishing the follicular variant (FV) of papillary thyroid carcinomas (PTC) from follicular neoplasms. By highlighting the "Orphan Annie-eyed" clear nuclei of the former, the Ultrafast Papanicolaou stain (UFP) easily separates these two entities. One thousand one hundred thirty-five ultrasound-guided FNAs of the thyroid were assessed by UFP with immediate biopsy results reported to the patients in a busy radiology office in Manhattan from November 1994 to December 1998. Of the 77 thyroid cancers resected, 22 were FVPTC and 17 were microcarcinomas (1 medullary carcinoma, 16 PTC). The rates of "unsatisfactory," "cancer," "suspicious for cancer," "follicular neoplasm," and "benign" cytology were 0.7%, 4.4%, 2.6%, 10.2%, and 82.1%, respectively and the cancer yields at surgery were 98%, 81.8%, 15.8%, and 0% respectively. Of the 1127 satisfactory FNAs in the series with a 2- to -6 years of clinical follow-up, a false-negative rate of 0% and a false-positive rate of 1.5% were obtained. Of the 169 surgical follow-ups with satisfactory FNAs, a sensitivity of 100%, specificity of 66.7%, positive predictive value of 87.4%, negative predictive value of 100%, and global accuracy of 89.9% were achieved. The paradoxical combination of low unsatisfactory rate and low false-negative rate is attributed to (1) the use of needle puncture without syringe to obtain enough microfollicles from the exceedingly bloody aspirates from follicular neoplasms for a diagnosis, (2) eliciting history of neck trauma to confirm hematomas, (3) using UFP to highlight the grape-like watery clear nuclei of FVPTC evident with a 4x objective, and (4) the precise guidance by ultrasound in sampling microcarcinomas.