Value of ultrasound-guided fine-needle aspiration biopsy of thyroid nodules in an endemic goitre area

The effect of surveillance for differentiated thyroid carcinoma in childhood cancer survivors on survival rates: a decision-tree-based analysis

Background

Childhood cancer survivors (CCS) who received radiation therapy exposing the thyroid gland are at increased risk of developing differentiated thyroid cancer (DTC). Therefore, the International Guideline Harmonization Group (IGHG) on late effects of childhood cancer therefore recommends surveillance. It is unclear whether surveillance reduces mortality.

Aim

The aim of this study was to compare four strategies for DTC surveillance in CCS with the aim of reducing mortality: Strategy-1, no surveillance; Strategy-2, ultrasound alone; Strategy-3, ultrasound followed by fine-needle biopsy (FNB); Strategy-4, palpation followed by ultrasound and FNB.

Materials and methods

A decision tree was formulated with 10-year thyroid cancer-specific survival as the endpoint, based on data extracted from literature.

Results

It was calculated that 12.6% of CCS will develop DTC. Using Strategy-1, all CCS with DTC would erroneously not be operated upon, but no CCS would have unnecessary surgery. With Strategy-2, all CCS with and 55.6% of CCS without DTC would be operated. Using Strategy-3, 11.1% of CCS with DTC would be correctly operated upon, 11.2% without DTC would be operated upon and 1.5% with DTC would not be operated upon. With Strategy-4, these percentages would be 6.8, 3.9 and 5.8%, respectively. Median 10-year survival rates would be equal across strategies (0.997).

Conclusion

Different surveillance strategies for DTC in CCS all result in the same high DTC survival. Therefore, the indication for surveillance may lie in a reduction of surgery-related morbidity rather than DTC-related mortality. In accordance with the IGHG guidelines, the precise strategy should be decided upon in a process of shared decision-making.

Clinical and pathologic features for predicting malignancy in thyroid follicular neoplasms

Background

The cytologic findings of follicular neoplasm do not distinguish between benign follicular adenoma and follicular thyroid carcinoma (FTC). The objective of this retrospective study was to identify clinical and cytologic/pathologic features to predict malignancy in patients preoperatively diagnosed with follicular neoplasms.

Methods

In total, 416 patients with follicular neoplasms who underwent thyroidectomy were reviewed at Seoul St. Mary's Hospital (Seoul, Korea) from January 2010 to June 2018. Clinicopathological features were analyzed retrospectively by complete medical chart review and pathologic slide review.

Results

Thyroid malignancy/noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) was diagnosed in 209 patients (50.2%). In total, 59 patients (14.2%) were diagnosed with FTC, 55 patients (13.3%) were diagnosed with follicular variant papillary thyroid carcinoma (fvPTC). The number of patients with PTC-related nuclear changes was higher in the malignancy/NIFTP group than in the benign group (16.3% vs. 1.9%, P<0.001). Multivariate analysis indicated that the significant risk factors for the diagnosis of malignancy/NIFTP include cytologic or pathologic diagnosis with PTC-related nuclear changes, NRAS mutation, and male sex.

Conclusions

The prevalence of malignancy in patients with a preoperative diagnosis of follicular neoplasm was much higher in our study than in previous reports. Cytologic or pathologic PTC-related nuclear changes is a useful predictor of the presence of malignancy. Further studies must be conducted to support our results.

[Modern thyroid surgery - the surgeon's endocrine-surgical understanding and his responsibility for the extent of surgery and complication rate]

Die hohe Qualität der Schilddrüsenchirurgie impliziert ein endokrin-chirurgisches Verständnis des Operateurs mit dem Ziel einer bestmöglichen Ergebnisqualität. Das beinhaltet ein befundadäquates Resektionsausmaß und eine möglichst niedrige Komplikationsrate. Der Chirurg sollte frühzeitig in die Operationsindikation eingebunden sein und auch selbst die Diagnostik, speziell den Schilddrüsen- und Halslymphknotenultraschall, sowie die Interpretation der Schnittbild- und nuklearmedizinischen Verfahren beherrschen. Im Besonderen sollte er über zeitgemäße Radikalitätsprinzipien in der Chirurgie Bescheid wissen.

Bei der gutartigen Struma ist eine individualisierte Operationsstrategie anzuwenden: Solitärknoten können auch einer gewebeschonenden Knotenresektion unterzogen werden. Bei multinodulärer Knotenstruma ist nicht zwingend eine totale Thyreoidektomie notwendig, die Vermeidung eines permanenten Hypoparathyreoidismus hat Priorität. Bei Rezidivstrumen ist oft die einseitige Operation des dominanten Befundes zu bevorzugen. Auch besteht zunehmend der Trend, die Indikation zur Entfernung der Schilddrüsenlappen seitengetrennt zu stellen. Die Basedow Struma erfordert eine Thyreoidektomie. Auch die hypertrophe Thyreoiditis Hashimoto kann eine Operationsindikation darstellen.

Die Radikalitätsprinzipien bei maligner Struma haben sich ebenfalls deutlich gewandelt als auch die strenge Indikation zur Radiojodtherapie. Das gilt speziell für papilläre Mikrokarzinome und minimal invasive follikuläre Tumortypen. Selbst bei medullären Schilddrüsenkarzinom stehen die Radikalitätsprinzipien im Hinblick auf synchrone oder metachrone laterale Halsdissektion in Diskussion.

Der Hypoparathyreoidismus stellt derzeit das Hauptproblem in der radikalen Schilddrüsenchirurgie dar. Recurrensparese und Nachblutung sind durch die subtile Operationstechnik selten geworden. Spezielle extrazervikale Operationszugänge sind nach wie vor in der Erprobungsphase und unter strengen Studienbestimmungen nur Zentren vorbehalten. Die Radiofrequenzablation stellt für gewisse Läsionen wie Zysten und autonome Adenome bei chirurgischer Kontraindikation ein alternatives Ablationsverfahren dar.

CORRELATIONS BETWEEN THE PRESENCE OF HÜRTHLE CELLS AND CYTOMORPHOLOGICAL FEATURES OF FINE-NEEDLE ASPIRATION BIOPSY IN THYROID NODULES

Introduction

The presence of Hürthle cells (HC) in fine needle thyroid biopsy (FNAB) is a real concern for a cytologist and also for an endocrinologist. We aimed to demonstrate if the presence of HC is associated with specific cytological features in FNAB results.

Material and Methods

This retrospective study analyzed 89 patients diagnosed with thyroid nodules, with FNAB; were two groups of patients: the study group A (HC+) (22 patients) with HC and control group B (HC-) (67 patients) with no HC; for both groups we analyzed the presence of 9 cytomorphologic features: overall cellularity, background colloid, lymphocyte infiltration, chronic inflammation, large nucleoli, small nucleoli, syncytial infiltration, nuclear pleomorphism/atypia, cellular pleomorphism.

Results

We found no statistical differences between age and gender. Nodules with diameter greater than 2 cm were present, more frequently in the group without HC, 43 (64.18%). The presence of HC is correlated with cellular pleomorphism (p=0.042) and nuclear pleomorphism (p < 0.0001) with no correlation between the other investigated parameters. The presence of colloid was correlated with the absence of HC (p= 0.014). In group with HC was a positive correlation with cellular pleomorphism and fibrosis. In the presence of fibrosis, HC was correlated with nuclear pleomorphism (p=0.03). In the group with HC without fibrosis there are more characteristic the sets with positive nuclear pleomorphism, positive large nucleoli and negative small nucleoli (p= 0.002).

Conclusions

The presence of HC in FNAB results is associated with colloid in small amounts, associated with nodules smaller than 2 cm, correlated with cellular pleomorphism and nuclear pleomorphism. Fibrosis can be a protective feature against malignancy because cellular parameters were not significantly associated with HC except the cellular pleomorphism.

Fine-Needle Aspiration with Immunohistochemistry Using a Modified Scrape Cell Block Technique for the Diagnosis of Thyroid and Parathyroid Nodules

OBJECTIVE

To evaluate the diagnostic accuracy of a modified scrape cell block (SCB) technique in a large series of patients. The technique was especially developed and tested for fine-needle aspiration of thyroid and parathyroid nodules.

STUDY DESIGN

Eighty-two ultrasound-guided fine-needle aspiration specimens with the sonographic aspect of a thyroid (n = 33) or a possible parathyroid nodule (n = 49) were studied. Immunohistochemistry (IHC) was used on cell blocks containing plasma, thromboplastin, and selected 3-dimensional cell aggregates scraped off Papanicolaou-stained smears. Antibodies for chromogranin A, thyroglobulin, parathyroid hormone, calcitonin, and carcinoembryonic antibody (CEA) were used. In cases of reduced immunosensitivity or suspected metastases or rare primary tumors, additional IHC markers were employed.

RESULTS

Chromogranin A was expressed in all 28 parathyroid adenomas (PA), in 7 of 8 hyperplastic parathyroid glands, and in 13 of 14 medullary thyroid carcinomas (MTC). When combining positivity for chromogranin A and calcitonin/CEA, the specificity for the detection of MTC was 100%. Parathyroid hormone was expressed in 26 of 36 parathyroid nodules (72.2%). When combining follicular microarchitecture and expression of chromogranin A, the specificity for the detection of parathyroid tissue was 97%.

CONCLUSION

With the modified SCB technique, accurate cytological diagnoses were obtained in 97.6% of 82 patients.

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.

Liquid base cytology in evaluation of thyroid nodules

Background

Palpable thyroid nodules are present in 4-7% of general population and Fine Needle Aspiration (FNA) is now accepted by endocrinologists and thyroid surgeons as a safe, simple and cost effective procedure for evaluating a thyroid nodule. The obtained sample can be spread directly on slides, processed as cell block preparations or prepared as liquid base smears. Liquid base method has been recently accepted due to its shorter preparation time and better preservation of nuclear details.

The aim of this study is to compare the diagnostic results of two commonly used methods: Liquid Base Preparation and Cell Block Preparation in evaluation of thyroid nodules.

Methods

The samples were taken from 100 patients with a solitary nodule or a prominent nodule on a multinodular goiter background (excluding hot nodules). The obtained samples were used to prepare conventional smears (CS), Cell Block Preparations (CBP) and Liquid Base Preparations (LBP). The slides were studied by two pathologists, considering the following parameters: Cellularity, Colloid, Lymphocytes/Plasma cells and Macrophages.

Results

87% of cases revealed informative results in LBP method while in the same group of patients only 69% of samples were informative after processing by CBP method. Sensitivity and specificity of both methods compared with the conventional smears and with each other and it is concluded that LBP is a reliable method for evaluating of a thyroid nodule. Other studies also show the same results.

Conclusion

The liquid base method should be trusted due to its easier procedure, cleaner slide background, its higher specificity and higher diagnostic yields. It can be used instead of CBP and in association with CS to increase the accuracy of evaluation of thyroid nodules.

The role of 18F-fluorodeoxyglucose positron emission tomography in differentiated thyroid cancer before surgery

The incidence of thyroid cancer in both men and women is increasing faster than that of any other cancer. Although positron emission tomography (PET) using (18)F-fluorodeoxyglucose (FDG) has received much attention, the use of FDG PET for the management of thyroid cancer is limited primarily to postoperative follow-up. However, it might have a role in selected, more aggressive pathologies, and so patients at a high risk of distant metastasis may benefit from PET before surgery. As less FDG-avid thyroid cancers may lower the diagnostic accuracy of PET in preoperative assessment, an understanding of FDG avidity is important for the evaluation of thyroid cancer. FDG avidity has been shown to be associated with tumor size, lymph node metastasis, and glucose transporter expression and differentiation. As PET is commonly used in clinical practice, the detection of incidentalomas by PET is increasing. However, incidentalomas detected by PET have a high risk of malignancy. Clinicians handling cytologically indeterminate nodules face a dilemma regarding a procedure for a definitive diagnosis, usually lobectomy. With 'nondiagnostic (ND)' fine-needle biopsy (FNA), PET has shown a negative predictive value (NPV) of 100%, which indicates that negative uptake in a ND FNA procedure accurately excludes malignancy. With 'atypia of undetermined significance' or 'follicular neoplasm', the sensitivity and NPV of PET are 84 and 88%. PET does not provide additional information for the preoperative assessment of thyroid cancer. However, factors associated with FDG positivity are related to a poor prognosis; therefore, FDG PET scans before surgery may facilitate the prediction of the prognosis of differentiated thyroid cancer.

The role of nuclear medicine in differentiated thyroid cancer

In differentiated thyroid cancer (DTC) nuclear medicine is able to cover the spectrum from diagnosis and treatment to follow up keeping patient's management in one institution. Nowadays, DTC is often diagnosed per chance, presenting as small indolent nodule diagnosed on routinely performed ultrasound. Ultrasound and ultrasonography-guided fine-needle aspiration biopsy together with scintigraphy are probably the most adequate tools for diagnosis. After thyroidectomy, treatment with iodine-131 is routinely performed in a nuclear medicine therapy institution as a standard procedure in most of the cases with regard to histology. In case of iodine positive metastases, repeated therapies can be performed in order to reduce tumour burden. In the follow up of DTC thyroglobulin (tumour marker), ultrasound and diagnostic whole body scan are established procedures. With the development of SPECT/CT and PET/CT ((18)F-FDG, (68)Ga-somatostatin receptor) combining functional and anatomic imaging the nuclear medicine spectrum has further increased.

[Epidemiology, pathophysiology, guideline-adjusted diagnostics, and treatment of thyroid nodules]

BACKGROUND

Clinically relevant thyroid carcinomas can be found in 5-6% of nodular goiters which undergo surgery. Moreover, multinodular goiters fre- quently contain hot areas. Therefore, efficient and rational methods for the differential diagnosis and decision are required to identify those nodules with an increased cancer risk or those which are hot among the many thyroid nodules.

METHODS

Description of a newly revised and further guidelines and consensus statements as well as selected literature search.

RESULTS

Already history, ultrasound and TSH (thyroid-stimulating hormone) determination do allow a first risk assessment for the further diagnostic work-up. Fine-needle biopsy (FNB) offers the best sensitivity and specificity for the distinction between benign and malignant thyroid nodules. The combination of several clinical and ultrasound criteria and laboratory determinations (calcitonin) can help with the selection of thyroid nodules with scintigraphically normal or decreased uptake > 1 cm for FNB. However, the efficiency of FNB requires sufficient training and experience of both the cytopathologist and the person performing FNB.

CONCLUSION

Whereas solitary thyroid nodules with a suspicion for malignancy should be referred to the surgeon, euthyroid thyroid nodules without clinical ultrasound or cytological indicators of malignancy may be followed up - possibly under medication -, if surgery is not indicated by local complaints, tracheal or mediastinal involvement.

Fine-needle aspiration biopsy versus ultrasound-guided fine-needle aspiration biopsy: cost-effectiveness as a frontline diagnostic modality for solitary thyroid nodules

BACKGROUND

Ultrasound-guided fine-needle aspiration biopsy (ultrasound-guided FNAB) is considered the diagnostic test of choice when a fine-needle aspiration biopsy (FNAB) returns an inconclusive diagnosis because of cytologic ambiguity or paucity of specimen.

METHODS

Cost-effectiveness analysis utilizing a decision tree was used to model the diagnostic strategies. The decision analysis model was parameterized using costs from a large, academic medical center and probabilities from existing literature. Outcomes included the incremental cost per additional case correctly diagnosed.

RESULTS

All data are reported as frontline ultrasound-guided FNAB strategy versus FNAB strategy-expected cost: $1329 versus $1312; expected number of cases correctly diagnosed (per 1000 biopsies): 980 versus 920; incremental cost per additional correctly diagnosed case: $289.

CONCLUSION

The use of ultrasound-guided FNAB as the initial modality for tissue biopsy of a thyroid nodule is more effective than traditional FNAB at an additional cost of $289 per additional correct diagnosis.

Current role of radionuclide imaging in differentiated thyroid cancer

Nuclear medicine plays an integral role in the management of differentiated thyroid cancer. This editorial aims to provide a summary of the current role of radionuclide imaging, including whole body iodine scan and fluorodeoxyglucose (FDG)-positron emission tomography (PET), in the diagnostic work-up and follow-up of patients with thyroid cancer.

Thyroid fine needle aspiration: how to improve clinicians' confidence and performance with the technique

Studies from single institutions report an acceptable accuracy rate for thyroid fine needle aspiration (FNA). However, FNA accuracy is much lower in many other centers in Europe and the USA and large multicenter studies indicate that the clinicians' confidence in the FNA technique remains low. One explanation for this is that there is an excess of inadequate and indeterminate findings for a follicular nodule at FNA cytology. In a University Hospital with large and qualified experience on thyroid nodule diagnosis, a review of 320 slides with an FNA diagnosis of indeterminate follicular nodule from different minor Italian Hospitals led to a different diagnosis in 61%. Since ancillary thyroid imaging may be overutilized and only a few authors report a proportion of excised nodules lower than 10%, we suspect that use of the FNA procedure is suboptimal. Several techniques are reported to improve the performance of thyroid FNA. Among these are tumor markers and large needle aspiration biopsy (LNAB). Immunodetection of the tumor marker galectin-3 has been evaluated by large multinational studies. Analysis of LNAB specimens reduces the number of inadequate FNA findings, improves the diagnostic determination of indeterminate follicular FNA findings and represents a better substrate for the determination of galectin-3. Therefore, we propose that clinical practice guidelines reflect these adjuvant techniques to thyroid FNA in order to improve selection criteria for thyroid nodule surgery.

The preoperative exclusion of thyroid carcinoma in multinodular goiter: Dynamic contrast-enhanced magnetic resonance imaging versus ultrasonography-guided fine-needle aspiration biopsy

BACKGROUND

We compared the diagnostic values of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and ultrasonography (USG)-guided fine-needle aspiration biopsy (FNAB) in the detection of thyroid carcinoma associated with multinodular goiter.

METHODS

USG-guided FNAB and DCE-MRI were performed consecutively on 26 patients who had multinodular goiter with dominant nodules and clinical suspicion of malignancy. DCE-MRI findings, cytodiagnosis, and final histopathologic results were correlated. We compared the sensitivity, specificity, diagnostic accuracy, and positive (PPV) and negative predictive values (NPV) of DCE-MRI and USG-guided FNAB.

RESULTS

Of 57 nodules in 26 patients, 16, 37, and 4 nodules showed delayed, plateau, and rapid washout patterns, respectively. Thyroid carcinoma was found in 8 patients (31%). Delayed washout pattern in a nodule was correlated with the histologic diagnosis of thyroid carcinoma (P < .001). None of the nodules with thyroid carcinoma had a plateau or rapid washout pattern. The sensitivity and NPV of DCE-MRI to diagnose thyroid carcinoma were greater when compared with those in USG-guided FNAB (100 vs 71.4%, and 100 vs 91.7%, respectively; P < .001).

CONCLUSION

When other diagnostic methods are inconclusive, DCE-MRI is superior to USG-guided FNAB to exclude thyroid carcinoma in patients with multinodular goiter.

The radiologist and the cytologist in diagnosing thyroid nodules: results of cooperation

PURPOSE

This study was done to evaluate the effectiveness of cooperation between the radiologist and the cytopathologist in ultrasound-guided fine-needle aspiration biopsy (FNAB) of thyroid nodules.

MATERIALS AND METHODS

Since 1995, FNAB of thyroid nodules at our department has been performed under ultrasound guidance by the radiologist with a cytopathologist present on-site. The results of ultrasound-guided FNAB procedures performed at our department in 1995, 1999, and 2005 were retrospectively evaluated and compared with those of other departments in the Trieste Province where thyroid nodules are sampled by palpation-guided FNAB performed by a clinician.

RESULTS

From 1995 to 2005, the number of ultrasound-guided FNAB procedures performed at our department rose steadily, whereas the number of inadequate samples fell progressively. In patients who underwent surgery, the number of discrepancies between the cytological findings and the final histological diagnoses decreased progressively.

CONCLUSIONS

Ultrasound-guided FNAB performed by the radiologist with a cytopathologist present on-site is superior to palpation-guided FNAB. The results are optimised by cooperation between the radiologist and cytologist.

Ultrasound-guided fine needle aspiration cytology in the diagnosis and management of thyroid nodules

OBJECTIVE

To examine the accuracy of fine needle aspiration cytology (FNAC) in the diagnosis of thyroid nodules and compare the inadequacy rates for ultrasound-guided and freehand FNAC.

METHODS

A retrospective study of 434 patients with thyroid nodules who underwent diagnostic FNAC over a 2-year period. Cytological diagnoses have been compared with the histological assessment of resection specimens in 69 cases.

RESULTS

The inadequacy rate was significantly lower from ultrasound guided FNAC (24/373 cases, 6.4%) than from freehand FNAC (8/61 cases, 13.1%) (P = 0.043). Seventy-six percentage of patients had a non-neoplastic cytological diagnosis and, after multidisciplinary review, the patients were reassured and assigned to clinical follow-up. Sixty-seven patients had a resection for cytological appearances consistent with non-neoplastic disease (n = 34), suspicious of follicular neoplasia (n = 23), or suspicious of malignancy (n = 10), and two patients had resections following inadequate cytology with ultrasound appearances suspicious of a neoplasm. The overall accuracy of FNAC analysis for malignancy was 97.0%, with sensitivity 83.3%, specificity 98.0%, positive predictive value 71.4% and negative predictive value 98.4%. The overall accuracy of FNAC analysis for the prediction of neoplasia was 97.5%, with sensitivity 80.5%, specificity 97.8%, positive predictive value 89.2% and negative predictive value 95.9%. Difficulties in cytological diagnosis were associated with lymphoid infiltrates and with degenerative changes in follicular adenomas.

CONCLUSION

Ultrasound-guided FNAC has a significantly lower yield of inadequate aspirates than palpable FNAC. The ability of FNAC to predict neoplasia in 89% patients and to exclude neoplasia in 95.9% patients makes an important contribution to the multidisciplinary assessment of patients.

Respective Roles of Thyroglobulin, Radioiodine Imaging, and Positron Emission Tomography in the Assessment of Thyroid Cancer

Depending on the iodine supply of an area, the incidence of thyroid cancer ranges between 4 and 12/100,000 per year. To detect thyroid cancer in an early stage, the assessment of thyroid nodules includes ultrasonography, ultrasonography-guided fine-needle aspiration biopsy, and conventional scintigraphic methods using (99m)Tc-pertechnetate, (99m)Tc-sestamibi or -tetrofosmin, and (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in selected cases. After treatment of thyroid cancer, a consequent follow-up is necessary over a period of several years. For following up low-risk patients, recombinant thyroid-stimulating hormone-stimulated thyroglobulin and ultrasonography is sufficient in most cases. After total thyroidectomy and radioiodine ablation therapy, thyroid-stimulating hormone-stimulated thyroglobulin should be below the detection limit (eg, <0.5 ng/mL, R: 70-130). An increase of thyroglobulin over time is suspicious for recurrent or metastatic disease. Especially in high-risk patients, aside from the use of ultrasonography for the detection of local recurrence and cervial lymph node metastases, nuclear medicine methods such as radioiodine imaging and FDG-PET are the methods of choice for localizing metastatic disease. Radioiodine imaging detects well-differentiated recurrences and metastases with a high specificity but only moderate sensitivity. The sensitivity of radioiodine imaging depends on the activity administered. Therefore a low activity diagnostic (131)I whole-body scan (74-185 MBq) has a lower detection rate than a high activity post-therapy scan (3700-7400 MBq). In patients with low or dedifferentiated thyroid cancer and after several courses of radioiodine therapy caused by metastatic disease, iodine negative metastases may develop. In these cases, despite clearly elevated levels of thyroglobulin, radioiodine imaging is negative or demonstrates only faint iodine uptake. The method of choice to image these iodine negative metastases is FDG-PET. In recent years the combination of PET and computed tomography has been introduced. The fusion of the metabolic and morphologic information was able to increase the diagnostic accuracy, reduces pitfalls and changes therapeutic strategies in a reasonable number of patients.

The impact of assessing specimen adequacy and number of needle passes for fine-needle aspiration biopsy of thyroid nodules

Fine-needle aspiration biopsy (FNAB) of thyroid nodules is a safe, cost-effective procedure but the rates of inadequate cytology specimens range from approximately 1% to 15%. This study tests the hypothesis that ultrasonographically (US) guided FNAB and onsite assessment of cytology improves the adequacy rate of FNAB. A retrospective analysis was performed on 693 thyroid FNAB specimens obtained with and without ultrasound guidance and with or without onsite cytology assessment. Overall, 29 specimens (4%) were inadequate for diagnosis. Among 163 cystic nodules and 530 solid nodules, inadequacy rates were 15% (n = 24) and 1% (n = 5) respectively (p = 0.0001). An onsite assessment of cytology for adequacy was done in 550 cases (83%), which was more accurately performed by a cytopathologist (97%) than a cytotechnologist (93%, p = 0.015). With US-guided FNAB, 3% of the cytology specimens were inadequate, compared to a 7% rate when US was not done (p = 0.003). The mean number of needle punctures necessary for an adequate specimen was 3.8 +/- 0.06 (median, 3.0; range, 1-11), which was different among various types of doctors, ranging from 3.2 +/- 0.07 to 5.4 +/- 0.12 (p = 0.001 analysis of variance [ANOVA]). The fewest number of needle passes to achieve an adequate specimen were required by university endocrinologists and pathologists working together (average, 3.2 +/- 0.07; median, 3.0; range, 1-11). Sample inadequacy rate varied significantly among physician groups, ranging from 3% to 18% (p = 0.0001 ANOVA). Stepwise regression analysis showed that onsite assessment of cytology, US-guided FNAB (p = 0.16), and cystic nature of the nodule (p < 0.0001 for all) correlated with adequacy of the specimen. We conclude that US-guided FNAB with onsite evaluation of cytology specimens substantially increases the adequacy of cytology specimens and decreases the number of required needle passes, which ultimately reduces patient discomfort and diagnostic errors, thus raising the question as to whether this should eventually become the standard of care. We believe this is a goal that training programs should strive to achieve.

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.

Cytopathology in Austria

Cervical cancer screening developed rapidly during the 1970s. Today, approximately 1.5 million smears are taken annually, so 50% of the target population are screened every year, 30% are cytologically underserved (24% never had a smears, 6% only once). This figure correlates with the fact that there are still 30% deaths from cervical cancer compared with 1960. Since 1998 a voluntary quality assurance programme was introduced by the Austrian Society of Cytology, based on comparison of results reported from participating laboratories.

An alternate model of thyroid cytology: practical not perfect

A sample of 384 thyroid cytology specimens prepared by cytospin over a 2.5-year period was classified by original report into inadequate, non-neoplastic and suspicious of neoplasia or worse. This was then compared with subsequent histology. The resulting data showed an inadequacy rate of 33%, a sensitivity of 55%, a specificity of 59%, a positive predictive value of 64% and a negative predictive value of 93%. On review of the cytology, in knowledge of the subsequent histology, the maximum achievable results were determined to have a positive predictive value of 79% and a negative predictive value of 97%. No clinically significant adverse event was detected.

Fluorine-18-fluorodeoxyglucose positron emission tomography in the preoperative assessment of thyroid nodules in an endemic goiter area

BACKGROUND

The aim of this study was to evaluate the usefulness of fluorine-18-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in the preoperative assessment of suspicious thyroid nodules.

METHODS

A total of 43 patients were examined before surgical resection. In all patients, imaging was obtained at 70 minutes after the intravenous administration of 180 MBq (18)F-FDG. Standard uptake values (SUVs) were calculated.

RESULTS

A total of 16 patients with thyroid carcinomas (11 papillary, 3 follicular, 2 anaplastic), 23 thyroid adenomas (11 microfollicular, 10 Hurthle cell, 2 macrofollicular), and 4 patients with degenerative goiter were found. (18)F-FDG uptake in Hurthle cell adenoma, thyroid cancer, microfollicular adenoma, degenerative goiter, and macrofollicular adenoma was 4.4 +/- 2.2, 3.7 +/- 1.9, 1.6 +/- 0.3, 1.2 +/- 0.2, and 0.9 +/- 0.1, respectively. Significant differences were observed between thyroid carcinomas and both microfollicular adenomas and degenerative goiters (P < 0.05), and between Hurthle cell adenomas and both microfollicular adenomas as well as degenerative goiter (P < 0.05). For diagnosis of thyroid carcinoma, 100% sensitivity, 63% specificity, and 100% negative predictive value was found when a cutoff value for SUV of 2 was used.

CONCLUSIONS

Our results indicate that thyroid carcinomas, in contrast to most benign thyroid nodules, demonstrate significantly increased glucose metabolism. (18)F-FDG PET is unlikely to differentiate successfully all benign tumors from malignant tumors, but it can help select patients who need surgery, especially if cytology is inconclusive or malignancy cannot be excluded.

Thyroid cancer: The Kuala Lumpur experience

BACKGROUND

There have been few detailed studies on thyroid cancer (TC) in Malaysia, a multiethnic country with three major races - Malays, Chinese and Indians.

METHODS

The paper retrospectively audits the records of 107 consecutive cases with histologically proven thyroid cancer between 1995 and 2000 presenting to University Hospital, Kuala Lumpur. The demographic distribution, histological variants, mode of presentation, sensitivity of fine needle aspiration cytology and the modalities of treatment are examined in the present paper.

RESULTS

Of a total of 107 cases of TC, 74 were papillary, 23 follicular, one Hurthle Cell, seven medullary and two anaplastic. There were 91 women and 16 men; the corresponding median age of presentation being 34.0 and 40.0 years. The median age at presentation of TC was 36 years in the Malay population, 37 in the Chinese population and 33 in the Indian population. Fifty-six per cent of follicular cancer incidence was in the Malay population alone, the remaining in the other populations. Solitary thyroid nodule was seen in 75 patients, generalized enlargement in 20 and no goiter in 11. Local symptoms were reported in <10% of patients. Preoperative FNAC had a sensitivity of 72.26%. Of 98 patients with well-differentiated TC (WDTC), total thyroidectomy was employed in 92. Surgery alone was used in 48 cases and combined with radioactive iodine ablation in the remaining 50.

CONCLUSION

All histological variants of TC are represented in the study. Well-differentiated TC forms the bulk with papillary cancer having the largest percentage. Follicular cancer is more common in the Malay population. Total thyroidectomy in WDTC, although controversial, remains the mainstay of surgical treatment in Malaysia.

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.

Thyroid nodules: pathogenesis, diagnosis and treatment

Thyroid nodules are very frequently found and their prevalence steadily increases with age. The discovery of such lesions by high-resolution radiological imaging procedures that have been performed for other indications raises the problem of how incidentally discovered thyroid nodules should be investigated in a cost-effective manner to identify the rare patient with a clinically significant malignancy. In this review the clinical criteria that prompt the evaluation of thyroid nodules are discussed, as is the currently recommended diagnostic approach, which principally relies on fine needle aspiration biopsy. The clinical implications of the different cytological diagnoses are discussed, with a special emphasis on the management of indeterminate, microfollicular lesions. Finally, the evidence for and against suppressive thyroid hormone therapy for benign thyroid nodules and multinodular goitres is discussed, with particular consideration of high-risk patients with prior external radiation therapy to the neck region.