Utility of cell blocks in the diagnosis of thyroid aspirates

The diagnostic value of add-on thyroid cell block in the evaluation of thyroid lesions

Objectives

Fine-needle aspiration (FNA) cytology plays a pivotal role in diagnosing thyroid nodules. Imaging assessment, followed by thyroid lesion sampling, is a widely applied clinical practice. Tissue fragments remnants are retrieved in cell-block providing an adjunct diagnostic tool for histopathology visualization and use of ancillary testing. This study aimed to evaluate whether the auxiliary application of cell-block adds to the diagnostic accuracy of the thyroid FNA.

Material and Methods

A total of 252 thyroid FNA cases between (2020 and 2021) were reviewed from patients aged 18-76. Of those, 150 cell-blocks were recovered and examined to assess their utility. Following categories were plotted during cell-blocks revision: (A) Inadequate material retrieved; (B) cell-block shows similar features along with their accompanying smears; and (C) value added to cytology diagnosis when using cell-block.

Results

The distribution of cell-blocks according to the aforementioned classification are as follows: A - non-diagnostic 63%, B - similar observation seen in both preparations 35%, and C - value added to the rendered diagnosis 2%. Hence, the use of cell-block improved cytology diagnosis in only 2% of total cases. Mostly were of immunostains application for diagnosis confirmation.

Conclusion

The non-diagnostic and atypical cytology cases have not been upgraded to a more meaningful category by the incorporation of cell-block performed with the routine non-enhancement random method. On the other hand, cell-blocks contributed generously toward immunostaining application in malignant scenarios.

Usefulness of cellblock preparation in fine needle aspiration for the diagnosis of thyroid nodules

BACKGROUND

Thyroid nodules are common in the general population. The current diagnostic method for nodules is the ultrasound guided fine needle aspiration (US-FNA). The aim of the study was to evaluate the usefulness of cellblock preparation in addition to routine US-FNA in the diagnosis of thyroid nodules.

METHODS

A retrospective study of patients with thyroid nodules submitted to US-FNA, with collection of material using both smears and cellblock preparation. Two air-dried smears were prepared for each nodule. After centrifugation, the residual aspirate in the syringe and needle was processed as a standard histology specimen (cellblock). Then a pathologist reviewed the smears and cellblock slides of each case.

RESULTS

A total of 12.360 thyroid nodules were submitted to US-FNA. Cellblock preparation was performed in 153 (1.2%) in addition to smears. Among the satisfactory cellblocks (80.5%, 120), 31.7% (38) provided additional morphological information in comparison with smears alone. No significant differences were found between the smear and the combined smear and cellblock evaluation concerning the number of unsatisfactory (12.1% vs. 11.4%, p = .85) and indeterminate (27.5% vs. 24.2%, p = .52) results. Overall, 10 samples (6.7%) had their diagnosis changed after cellblock evaluation, nine of them due to immunohistochemical studies. Immunohistochemistry confirmed parathyroid origin of the nodule in six cases.

CONCLUSION

Cellblocks did not contribute to increase cellularity of the samples or to reduce indetermined results of FNA of thyroid nodules. Immunohistochemistry was essential to characterize rare cases without follicular histogenesis. Cellblock must only be prepared when considering performing immunohistochemistry.

Correlation between fine-needle aspiration cytology, cell block cytology, and histopathology in the diagnosis of thyroid lesions

Context:

Fine-needle aspiration cytology is considered the gold standard screening test in the evaluation of a thyroid nodule. We studied whether cell block cytology can be used in addition to conventional smears for the evaluation of tissue from fine-needle aspirations or fluid aspirations and also compared it with histopathological diagnosis.

Aims:

The primary aim of this study was to know the utility of cell blocks in the diagnosis of thyroid lesions.

Settings and Design:

This was a prospective observational study conducted from June 2018 to September 2020 at a tertiary Care Hospital in Eastern India. Ethical approval was obtained from the Ethics Committee of the institution. Patients above 18 years who presented with goiter were included in the study. Thirty patients were enrolled in the study after informed consent.

Methods and Material:

Smears prepared from the aspirates were stained with Leishman-Giemsa (LG) and Pap stain. The remnant from the needle hub was transferred to a sterile container. Cell blocks were prepared from the remnants. Smears were scored based on cell obscuration by blood, cellularity, cell degeneration, and cell architecture. The results were compared with histopathology.

Statistical Analysis Used:

Data were recorded using Microsoft Excel. Descriptive statistics, frequency, and proportion were used to describe demographic variables.

Results:

The majority of the patients (23.3%) were in their third decade of life, followed by 16.7% of the patients in their fourth and fifth decades. The patient age ranged from 25 to 80 years, with a mean age of 50.83 years and a standard deviation of 16.72. The largest number of patients were females accounting for 80% (24/30) of the total participants. The majority of the patients (36.7%) (11/30) had thyroid gland enlargement for a period of 15 days to three months. 14% of the participants were not able to recall its duration. The majority (60%) (18/30) had left lobe lesions, followed by 33.3% (10/30) who had right lobe lesions, and 6.7% (2/30) who had bilateral lobe swelling. The mean size of the lesion was 2.84 cm. 50% were found to be Bethesda II lesions, while 13.3% were Bethesda IV, and 36.7% were found to be Bethesda VI lesions. The cell block score (7) was found to be better compared to Fine Needle Aspiration Cytology (FNAC) (4.7). Tissue Coagulum Clot and Clot Scrape methods were found to yield better results compared to the Cytocentrifuge method. The P value was found to be significant (<0.001).

Conclusions:

Cell blocks were found to improve the cell morphology compared to FNAC alone and can be used as an adjunct to FNAC in the diagnosis of various thyroid lesions.

Utility of cell block as an adjunct to liquid-based cytology for diagnosing papillary thyroid carcinoma

Background

Although liquid-based cytology (LBC) has gained popularity among clinical laboratories, it is unclear whether it is equivalent to conventional smears for making a definite diagnosis of papillary thyroid carcinoma (PTC). The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) suggests a definite diagnosis of PTC is preferred when there are at least one of three features (papillary architecture, psammomatous calcifications, and frequent pseudonuclear inclusions) plus other typical cytomorphological findings. This study evaluated whether an additional cell block (CB), prepared from the residual LBC material, could help improve the diagnosis of PTC.

Materials and Methods

A total of 62 cases with both ThinPrep LBC and CB preparations and histopathological follow-up of PTC were retrieved between November 2016 and March 2019. The ThinPrep LBC and CB slides were reviewed separately to identify any papillary architecture, psammomatous calcifications, or pseudonuclear inclusions for diagnosing PTC.

Results

Among the 51 cases with cytological diagnosis of PTC in the LBC+CB slides, the CB provided additional diagnostic information in 15 cases, which were initially diagnosed as suspicious for PTC based on the LBC slides alone. This information included papillary architecture (n=11), psammomatous calcification (n=1) and pseudonuclear inclusions (n=5). The number of specimens in the 51 cases containing at least one of the three features increased from 42 (LBC) to 51 (LBC+CB). The accuracy for diagnosing PTC increased from 58.1% for LBC alone to 82.3% for the LBC+CB examination.

Conclusion

An adjunctive CB preparation may improve the LBC technique for diagnosing PTC.

Culture Cell Block Controls as a Tool to the Biomolecular Diagnosis of Infectious Diseases

The cell block (CB) technique has allowed easy obtainment of samples such as cellular and culture suspensions, to perform specific molecular tests such as immunohistochemistry and in situ hybridization. It has been improved along time, accuracy, and quality of the diagnoses, however, the cost of a commercial gel matrix for the preparation of CB is high and not suitable depending on the situation. The objective of this study is to test agarose as an alternative to the commercial gel matrix in the preparation of Aspergillus fumigatus' CB.

Architectural aspects of cell-blocks as small biopsies

Cell-block preparations have become an essential part of integrated cytology diagnosis. They are essentially microbiopsies that are formalin fixed and embedded in paraffin. This has become more prevalent with greater sample procurement due to the advent of newer biopsy techniques and needles. Cell-blocks allow retrieval of small tissue fragments from cytology specimens that sometimes cannot be processed by alternate cytologic techniques. They represent concentrated, cell-enriched preparations that provide cytologists with the opportunity to evaluate cellular architecture, as well as to perform ancillary testing. A cell-block compatible sample may thus obviate the need for a more invasive procedure such as a tissue biopsy. Microscopic examination of cell-blocks is quick, avoids obscuring material, permits cells to be evaluated in one focal plane, and allows the histologic architecture such as glandular differentiation, papillary formations, and sometimes invasion to be easily identified. This new era of “cytohistology” accordingly requires practicing cytologists to become more familiar with histopathology. This review article discusses the benefit of various architectural patterns identifiable in cell-blocks employed as an adjunct to Pap tests, exfoliative fluid specimens, and fine-needle aspirations.

Diagnostic utility of cell block in fine needle aspiration cytology of thyroid gland

BACKGROUND

This study was conducted to evaluate the diagnostic utility of cell block material in fine needle aspiration (FNA) of thyroid nodules.

DESIGN

A total of 242 thyroid fine need aspirations (FNAs) were performed between January 2015 and December 2015. Of those, all consecutive thyroid FNA cases with cell blocks (n = 140) from 129 patients (age: 58.9 ± 12.8 years) are included in this study. Cytology slides and cell blocks are reviewed for adequacy assessment based on the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) and then categorizing them into TBSRTC diagnostic categories. These cases are divided into two groups, combined cytology and cell block (C + CB) and cytology without cell block (C).

RESULTS

In the first group (C + CB), a total 140 cases are categorized in TBSRTC as follows: I: 13 (9.3%) cases, II: 78 (55.7%) cases, III: 7 (5%), IV: 16 (11.4%), V: 3(2.2%) and VI: 23 (16.4%). In the second group (C), the cases are classified in TBSRTC as follows: I: 23 (16.4%) cases, II: 70 (50%), III: 7 (5%), IV: 16 (11.4%), V: 3 (2.2%) and VI: 21 (15%). Nondiagnostic rate was 7.1% lower in the first group (C + CB) as compared with second group (C) (First group: 9.3% vs second group: 16.4%, P = .0764).

CONCLUSIONS

Combined use of cytology slides and cell block decreases the nondiagnostic rate up to 7.1% as compared with cytology without cell block.

Increasing diagnostic effectiveness of thyroid nodule evaluation by implementation of cell block preparation in routine US-FNA analysis

OBJECTIVE

Ultrasound-guided fine-needle aspiration (US-FNA) biopsy has proven to be an accurate and efficient tool in thyroid nodule evaluation. We evaluated whether cell block adds to the diagnostic accuracy of US-FNA.

SUBJECTS AND METHODS

Three hundred twenty-eight consecutive patients underwent US-FNA, cytology and cell block evaluation. Six slides were prepared for each patient and stained by Papanicolaou and Giemsa techniques. The residual hemorrhagic aspirate in the syringe and needle was fixed in 10% formalin and paraffin-embedded (cell block). The histological sections were examined as a complementary diagnostic tool to US-FNA.

RESULTS

The study population comprised 89% females and the mean age was 57.4 ± 13.7 years. The mean nodule size was 2.3 ± 1.2 cm. US-FNA cytological results were as follows: Bethesda I, 17.1% (n = 56); Bethesda II, 61.6% (n = 202); Bethesda III, 9.5% (n = 31); Bethesda IV, 5.8% (n = 19); Bethesda V, 2.4% (n = 8), and Bethesda VI, 3.6% (n = 12). Cell blocks were obtained in 100% of cases and were considered diagnostic in 89.6%. Combined cytological and cell block (cyto-cell block) results were as follows: unsatisfactory, 4.3% (n = 14); benign, 72.6% (n = 238); indeterminate, 11.3% (n = 37); follicular lesion, 5.8% (n = 19); suspicious for malignancy, 2.4% (n = 8), and malignant, 3.6% (n = 12). The sensitivity and specificity for cyto-cell block was 100% and 90%, respectively, and the accuracy was 94%. Cyto-cell block analysis reduced the rate of unsatisfactory samples (p < 0.001).

CONCLUSIONS

The cyto-cell block interpretation improved the efficiency of US-FNA. This simple, fast and low-cost technique should be used as an adjunctive test in thyroid nodule evaluation. Arch Endocrinol Metab. 2016;60(4):367-73.

Undifferentiated Malignant Neoplasm Involving Parotid and Thyroid: Sampling and PAX8 Cross-Reactivity Can Obscure the Diagnosis of Lymphoma

Poorly differentiated malignant neoplasia arising within the head and neck region may originate from diverse sources. We report a case of a cytologically undifferentiated malignant neoplasm clinically presenting as masses involving thyroid and parotid. Although PAX8 was immunoreactive and thus worrisome for anaplastic thyroid carcinoma, the tumor was eventually proven to represent PAX5 positive diffuse large B-cell lymphoma expressing cross-reactivity with polyclonal PAX8 antibody. Cross-reactivity between commercially available polyclonal PAX8 and PAX5 immunostains has been described in the literature but is not widely known, and it is a potential pitfall for making a misdiagnosis. This distinction can have importance in selection of subsequent clinical therapy and should be considered in choice of immunohistochemical stains for diagnostic purposes.

Cell-block procedure in endoscopic ultrasound-guided-fine-needle-aspiration of gastrointestinal solid neoplastic lesions

In the present review we have analyzed the clinical applications of endoscopic ultrasound-guided-fine-needle-aspiration (EUS-FNA) and the methodological aspects obtained by cell-block procedure (CBP) in the diagnostic approach to the gastrointestinal neoplastic pathology. CBP showed numerous advantages in comparison to the cytologic routine smears; in particular, better preservation of cell architecture, achievement of routine haematoxylin-eosin staining equivalent to histological slides and possibility to perform immunohistochemistry or molecular analyses represented the most evident reasons to choose this method. Moreover, by this approach, the differential diagnosis of solid gastrointestinal neoplasias may be more easily achieved and the background of contaminant non-neoplastic gastrointestinal avoided. Finally, biological samples collected by EUS-FNA CBP-assisted should be investigated in order to identify and quantify further potential molecular markers.

Comparison of the Cellient(™) automated cell block system and agar cell block method

OBJECTIVE

To compare the Cellient(TM) automated cell block system with the agar cell block method in terms of quantity and quality of diagnostic material and morphological, histochemical and immunocytochemical features.

MATERIALS AND METHODS

Cell blocks were prepared from 100 effusion samples using the agar method and Cellient system, and routinely sectioned and stained for haematoxylin and eosin and periodic acid-Schiff with diastase (PASD). A preliminary immunocytochemical study was performed on selected cases (27/100 cases). Sections were evaluated using a three-point grading system to compare a set of morphological parameters. Statistical analysis was performed using Fisher's exact test.

RESULTS

Parameters assessing cellularity, presence of single cells and definition of nuclear membrane, nucleoli, chromatin and cytoplasm showed a statistically significant improvement on Cellient cell blocks compared with agar cell blocks (P < 0.05). No significant difference was seen for definition of cell groups, PASD staining or the intensity or clarity of immunocytochemical staining. A discrepant immunocytochemistry (ICC) result was seen in 21% (13/63) of immunostains.

CONCLUSION

The Cellient technique is comparable with the agar method, with statistically significant results achieved for important morphological features. It demonstrates potential as an alternative cell block preparation method which is relevant for the rapid processing of fine needle aspiration samples, malignant effusions and low-cellularity specimens, where optimal cell morphology and architecture are essential. Further investigation is required to optimize immunocytochemical staining using the Cellient method.

Cell blocks in cytopathology: a review of preparative methods, utility in diagnosis and role in ancillary studies

The cell block (CB) is a routine procedure in cytopathology that has gained importance because of its pivotal role in diagnosis and ancillary studies. There is no precise review in the published literature that deals with the various methods of preparation of CB, its utility in diagnosis, immunocytochemistry (ICC) or molecular testing, and its drawbacks. An extensive literature search on CB in cytology using internet search engines was performed for this review employing the following keywords: cell block, cytoblock, cytology, cytopathology, methods, preparation, fixatives, diagnostic yield, ancillary and molecular studies. Ever since its introduction more than a century ago, the CB technique has undergone numerous modifications to improve the quality of the procedure; however, the overall principle remains the same in each method. CBs can be prepared from virtually all varieties of cytological samples. In today's era of personalized medicine, cytological specimens, including CBs, augment the utility of cytological samples in analysing the molecular alterations as effectively as surgical biopsies or resection specimens. With the availability of molecular targeted therapy for many cancers, a large number of recent studies have used cytological material or CBs for molecular characterization. The various techniques of CB preparation with different fixatives, their advantages and limitations, and issues of diagnostic yield are discussed in this review.

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 (≥75 ng/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.

PAX8 is expressed in anaplastic thyroid carcinoma diagnosed by fine-needle aspiration: a study of three cases with histological correlates

OBJECTIVE

It is difficult to diagnose anaplastic thyroid carcinoma (ATC) in a fine-needle aspiration (FNA) sample because, given the loss of morphological and immunophenotypical follicular thyroid features, its cytology resembles that of other undifferentiated neoplasms. Recent studies have shown that immunostaining for paired box gene 8 (PAX8), a transcription factor expressed in normal thyroid, is effective for diagnosing ATCs on histology. The aim of this study was to evaluate whether PAX8 could be used to identify ATCs on cytology also.

DESIGN AND METHODS

We selected three PAX8-immunostained undifferentiated FNA samples previously diagnosed as suspected ATCs, whose cell block had been negative for the expression of TGB and thyroid transcription factor-1. Matched histological samples, available in two cases, were also processed for PAX8 immunohistochemistry.

RESULTS

All three FNA samples were PAX8 positive. Two samples that had an epithelioid pattern showed a diffuse, intense nuclear signal. The third sample, which had a spindle-cell pattern, showed less intense and more patchy staining. Matched histology yielded overlapping results.

CONCLUSIONS

PAX8 immunocytochemistry can help cytopathologists to diagnose ATCs.

Ultrasound-guided fine-needle aspiration biopsy of the thyroid: methods to decrease the rate of unsatisfactory biopsies in the absence of an on-site pathologist

PURPOSE

The rate of unsatisfactory samples from ultrasound-guided fine-needle aspirations of thyroid nodules varies widely in the literature. We aimed to evaluate our thyroid ultrasound-guided fine-needle aspiration biopsy technique in the absence of on-site microscopic examination by a pathologist; determine factors that affect the adequacy rate, such as the number of needle passes and needle size; compare our results with the literature; and establish an optimal technique.

MATERIALS AND METHODS

We performed a retrospective review of cytopathology reports from 252 consecutive thyroid ultrasound-guided fine-needle aspiration biopsies performed by a radiologist between 2005 and 2010 in our hospital's radiology department. Sample adequacy, the number of needle passes, and needle size were determined. There was an on-site cytologist who prepared slides immediately after fine-needle aspiration but no on-site microscopic assessment of sample adequacy to guide the number of needle passes that should be performed. Cytopathology biopsy reports were classified as either unsatisfactory or satisfactory samples for diagnosis; the latter consisted of benign, malignant, and undetermined diagnoses.

RESULTS

Seventy-seven biopsies were performed with 1 needle pass, 124 with 2 needle passes, and 51 with 3 needle passes. The rates of unsatisfactory biopsies were 33.8%, 23.4% (odds ratio [OR] 0.599 [95% confidence interval {CI}, 0.319-1.123]; P = .110), and 13.7% (OR 0.312 [95% CI, 0.124-0.788]; P = .014), respectively.

CONCLUSION

In a hospital in which there is no on-site pathologist, a 3-pass method increases the specimen satisfactory rate by 20% compared with 1 pass, achieves similar rates to the literature, and provides a basis for further improvement of our practice.

Immunocytochemistry with cytokeratin 19 and anti-human mesothelial cell antibody (HBME1) increases the diagnostic accuracy of thyroid fine-needle aspirations: preliminary report of 150 liquid-based fine-needle aspirations with histological control

BACKGROUND

Thyroid nodules are relatively common (7% of the population) but are malignant in only 5%-10% of cases. Fine-needle aspiration (FNA) to detect cancer can have > 90% sensitivity but only 50%-65% specificity because of false-positive results, which necessitates surgical controls. We aimed to assess the diagnostic accuracy of immunocytochemistry (ICC) of thyroid FNA to improve its sensitivity and specificity.

METHODS

We prospectively collected 2038 thyroid FNAs, of which 1397 were FNA biopsies with liquid-based cytology (Thin-Prep-Hologic®). ICC with cytokeratin 19 and HBME1 antibodies (Dako® A/S) was used for all malignant cases and cases of atypical cells of undetermined significance (AUS), follicular neoplasm (FN), and nodules suspicious for malignancy-papillary thyroid carcinoma (SM-PTC) as well as some benign cases (abnormal features on radiography or benign on secondary FNA). ICC results were defined as "non-contributory," "favoring benign," "favoring malignant," or "indeterminate." Results for 150 cases were compared with histological controls for diagnostic accuracy.

RESULTS

Of these 150 cases ICC was helpful for benign or malignant triage of 48 cases of AUS, FN, and SM-PTC (42% of these lesions). Six (4%) ICC results were false positive (favoring malignant with benign histology) but none were false negative (favoring benign with malignant histology). Results for indeterminate cytological cases favored malignant or benign disease with sensitivity, specificity, and negative and positive predictive values of 100%, 85.2%, 100%, and 86.2%, respectively.

CONCLUSIONS

ICC of thyroid FNAs with cytokeratin 19 and HBME1 antibodies can reduce the false-positive and false-negative results of single morphological analyses. It can increase the sensitivity and specificity of diagnosis, thus improving diagnostic accuracy and reducing the need for surgical controls.

Factors affecting inadequate sampling of ultrasound-guided fine-needle aspiration biopsy of thyroid nodules

PURPOSE

The aim of this study was to evaluate the overall ultrasonographic features and clinical factors that contribute to inadequate sampling in ultrasound-guided fine-needle aspiration biopsy (US-FNAB) of thyroid nodules.

MATERIALS AND METHODS

From April 2008 to December 2008, 4077 US-FNABs in 3767 consecutive patients were reviewed. We evaluated the clinical, ultrasound and pathological features of patients and analysed the association between these features and inadequate samples. We also compared inadequate sample rates according to the experience of the performing doctor.

RESULTS

The inadequate sample rate was 16·1% (654/4077). Univariate analysis revealed an association between inadequate samples and cyst dominancy, macrocalcification and benign pathology of the nodule. The inadequate sample rate was also higher in the inexperienced group than in the experienced group. In multivariate analysis, cyst dominancy and macrocalcification of a nodule were significantly associated with inadequate samples in the experienced group.

CONCLUSION

Cyst dominancy and macrocalcifications in thyroid nodules, inexperience of the performing doctor and benign pathology were factors associated with high inadequate sample rates of US-FNAB in thyroid nodules.

Metastasis of colon cancer to the thyroid gland: a case diagnosed on fine-needle aspirate by a combined cytological, immunocytochemical, and molecular approach

Fine-needle aspiration (FNA) with cytological evaluation reliably diagnoses primary and secondary thyroid neoplasms. However, identifying the primary origin of a metastatic process involving the thyroid gland is challenging. In particular, metastasis of colon cancer to the thyroid gland is very rare. In this case report, a right lobe solid thyroid nodule in a 66-year-old male was aspirated. FNA cytology showed necrosis and atypical tall columnar cells; since, the patient at age 60 had undergone surgery for a sigmoid-rectal cancer metastasizing to the liver and subsequently to the lung, a suspicion of metastasis from colon cancer was raised. This was corroborated by cell-block immunocytochemistry showing a cytokeratin (CK) 7 negative/CK20-positive staining pattern; thyreoglobulin and TTF-1 were both negative. Since KRAS codon 12/13 mutations frequently occur in colon cancer, whereas they are extremely uncommon in primary thyroid tumors, DNA was extracted from the aspirated cells, and KRAS mutational analysis was carried out. The codon 12 G12D mutation was found; the same mutation was evident in the primary cancer of the colon and in its liver and lung metastasis. Thus, a combined cytological, immunocytochemical and molecular approach unquestionably correlated metastatic adenocarcinoma cells aspirated from the thyroid to a colo-rectal origin.

Cyclin D1 and D3 overexpression predicts malignant behavior in thyroid fine-needle aspirates suspicious for Hurthle cell neoplasms

BACKGROUND

Thyroid fine-needle aspiration (FNA) samples that feature a follicular-patterned, monotonous Hurthle (oncocytic) cell population cannot be diagnosed reliably. The authors of this report recently identified cyclin D3 overexpression on histologic sections of Hurthle cell carcinoma. In this study, they assessed the diagnostic value of cyclin D3 immunohistochemistry added to routine cytology.

METHODS

Fifty-one FNA samples that were suspicious for Hurtle cell neoplasia and that had histologic follow-up (19 malignant cases) were examined. Cyclin D3 expression levels were evaluated in cell block preparations and were compared with levels of the closely related cyclin D1 protein.

RESULTS

Greater than 25% positive cells were used as the cutoff point, as suggested by previous studies. Cyclin D1 and cyclin D3 were highly specific (100% for both) and fairly accurate (75% and 92%, respectively) in distinguishing between benign and malignant oncocytic lesions; the positive predictive value (PPV) for each was 100%. However, both cyclins D1 and D3 had low sensitivity (32% and 79%, respectively) and low negative predictive value (NPV) (71% and 89%, respectively). In contrast, by adopting balanced receiver operating characteristic-derived positive cutoff values, cyclin D1 (>or=6.5%) and cyclin D3 (>or=7.5%) were found to be highly sensitive (100% for both) and accurate (90% and 94%, respectively); and the NPV was 100% for both. In contrast, cyclins D1 and D3 had low specificity (84% and 91%, respectively) and a low PPV (79% and 86%, respectively); however, these values improved in samples that were positive for both cyclins (sensitivity, 100%; specificity, 94%; PPV, 90%; NPV, 100%; and accuracy, 96%).

CONCLUSIONS

Cyclin D3 increased the suspicion of malignancy in indeterminate oncocytic lesions; its diagnostic performance depended on the cutoff point used and was enhanced further when combined with cyclin D1.

Comparison of Thin-Prep and cell block preparation for the evaluation of Thyroid epithelial lesions on fine needle aspiration biopsy

Background

The objective of this study was to compare the utility of Thin-Prep (TP) cytologic preparation with that of Cell Block (CB) preparation in the diagnosis of thyroid lesions, mainly follicular epithelial lesions, by fine needle aspiration biopsy (FNAB). Feasibility of using the TP slides for immunocytochemical stains is also discussed.

Methods

A total of 126 consecutive cases of thyroid FNAB with TP slides and 128 consecutive cases of thyroid FNAB with CB slides were reviewed blindly by two cytopathologists. The presence of colloid, follicular cells, macrophages and lymphocytes/plasma cells were recorded and scored 0–4 on each case based on TP or CB slide review. The cytologic diagnoses were grouped as follows: cyst, colloid nodule, colloid nodule with cystic change, chronic thyroiditis, atypical/neoplastic and non-diagnostic.

Results

The TP slides had higher diagnostic rate than CB slides. The diagnostic yield was 68% of the TP slides whereas only 24% of the CB slides were diagnostic. Also, only 4 atypical/neoplastic lesions were diagnosed on the TP slides and the corresponding direct smears, while 5 cases of atypical/neoplastic lesions were diagnosed on the smears but could not be diagnosed on the corresponding CB slides. Additionally, the TP slides revealed cytologic features that were not observed on the direct traditional smears of the same case.

Conclusion

In thyroid FNAB cases, TP slide preparation is superior to CB slide preparation and is more likely to have greater cellularity for diagnosis and detect atypical/neoplastic thyroid lesions, particularly those of follicular cell origin. Furthermore, TP slides appear to detect helpful diagnostic cytologic features and should be considered complementary to, rather than replacing, direct smears.

[Fine-needle aspiration cytology. Aspects of a minimally invasive diagnostic procedure]

All practicable applications of fine-needle aspiration cytology (FNAC) for palpable tumors or non-palpable lesions guided with endoscopic and imaging procedures are presented. Multidisciplinary procedures and the technical and biological aspects of FNAC are presented. Indications and diagnostic challenges of FNAC on selected organs and neoplasms are discussed based on personal experience and the literature. Skilled and well-trained cytopathologists, the quality of the aspirate and the cytological preparation as well as supplementary immunocytochemical and molecular genetic analyses are mandatory for reliable diagnostic results. The indications and advantages of liquid-based techniques are discussed.

Utility of millipore filter and cell block in thyroid needle aspirates: Which method is superior?

The main goal of thyroid fine-needle aspiration (FNA) is to distinguish nodules that require surgery from those that do not, thereby decreasing the number of diagnostic thyroidectomies. Several cytologic preparations are used to reach a definitive diagnosis, including smears using conventional stains, such as Diff-Quik (DQ) and Papanicolaou (Pap), millipore filters (MF), and cell blocks (CB). This study is undertaken to study the efficacy and adequacy to reach a definitive diagnosis of two cytologic preparations, MF and CB, in thyroid aspirates. All thyroid needle aspirates performed at Emory University Hospitals from January 2003 to April 2005 that had both MF and CB preparations for microscopic evaluation were studied. Conventional stains (DQ and Pap) were prepared. An initial aliquot of the specimen was divided for MF, and the remaining specimen submitted for CB preparation. All MF and CB slides were reviewed blindly. Adequacy criteria were assessed as 6-8 groups of follicular cells, with each containing 10 or more cells. Patient demographics, cytologic diagnoses, and follow-up information were retrieved. A total of 218 cases met our criteria; 21 of these cases were excluded due to lack of available diagnostic slides. Thus, a total of 197 cases were studied. Approximately two-third of the cases (57.9%) were diagnosed on DQ- and Pap-stained smears only, in which both CB and MF were inadequate. About 4.6% of the cases were diagnostic on both CB and MF; 36.0% on MF only, and 1.5% on CB preparation only. In more than half the cases (57.9%), diagnosis of thyroid FNA was rendered only on conventional stained smears. MF smears appeared to be superior for diagnostic yield (40.6%) than CB (6.1%), which is dependent on specimen cellularity. Therefore, MF rather than CB should be added to conventional stained smears (DQ and Pap) to supplement the diagnostic yield, especially in specimens of low cellularity.