Pathologist-performed ultrasound-guided fine-needle aspirations of the thyroid: A single institution observational study.

BACKGROUND: Ultrasound-guided fine-needle aspiration biopsies (USFNAs) are increasingly performed by pathologists. This study was designed to assess the diagnostic yield and characterization of thyroid nodules biopsied at a teaching hospital setting in which both attending physicians and trainees are involved in the performance of USFNAs. METHODS: A retrospective study of pathologist-performed USFNAs of thyroid cases was performed over a period of 9 years at a tertiary medical center. Data collected included patient characteristics and The Bethesda System diagnostic categories. RESULTS: Over the study period, 1531 USFNAs of thyroid nodules were performed in the pathology-based clinic, with 1209 lesions in females and 322 in males. Ninety-three percent of samples were sufficient for diagnosis (n = 1420). The majority of nodules biopsied were benign (65.4%, n = 1002). Overall, 3.1% of nodules biopsied were diagnostic of malignancy (n = 47). The number of USFNAs over the years showed a rapid increase initially, with a coronavirus disease 2019-related decrease in 2020. CONCLUSIONS: The authors report their experience with thyroid USFNA over nearly a decade. The most common diagnosis was benign and the second most common was Bethesda category III. Lesions that were diagnostic of malignancy were relatively uncommon. Over the study period, the results showed that at a large tertiary care center in which USFNAs were performed by trainees as well as attending physicians, the diagnostic yield was good with a majority of thyroid nodules biopsied associated with a definitive diagnosis.

Performance of repeat cytology with reflex ThyroSeq genomic classifier for indeterminant thyroid cytology.

BACKGROUND: The American Thyroid Association recommends either repeat fine-needle aspiration biopsy (FNAB) or molecular testing (eg, ThyroSeq) of Bethesda category III (atypia of undetermined significance/follicular lesion of undetermined significance [AUS/FLUS]) nodules to provide further risk stratification. How a testing algorithm that uses ancillary molecular tests performs as a reflex test for repeat sampling of indeterminant nodules remains unclear. METHODS: Thyroid FNABs performed over a 24-month period that received a diagnosis of AUS/FLUS and underwent subsequent FNAB were analyzed. RESULTS: In total, 187 patients were identified who received an FNAB diagnosis of AUS/FLUS and had repeat sampling. Of these patients, 64% received a subsequent indeterminant diagnosis on repeat biopsy: 7 (3.7%) repeat biopsies were diagnosed as nondiagnostic/unsatisfactory, 104 (55.6%) were diagnosed as AUS/FLUS, and 8 (4.3%) were diagnosed as follicular neoplasm/suspicious for follicular neoplasm. Of the repeat biopsied nodules, 63% underwent subsequent testing with ThyroSeq version 3. The diagnostic performance was calculated using only surgically confirmed nodules (sensitivity, 100%; specificity, 30%; positive predictive value, 41%; negative predictive value, 100%) and by assigning nonresected nodules with negative ThyroSeq or benign cytology results as benign (sensitivity, 100%; specificity, 88%; positive predictive value, 41%; negative predictive value, 100%). CONCLUSIONS: In the majority of patients, repeat FNAB for AUS/FLUS did not preclude subsequent molecular ancillary testing because of the high rate of indeterminant results on repeat biopsy. The diagnostic performance of the testing algorithm reported here was very similar to other reports using either repeat biopsy or molecular testing alone. Ultimately, the algorithm of performing molecular testing on repeat indeterminant nodules increased the number of biopsies performed and lengthened the time to definitive risk stratification without a disproportionate decrease in the use of molecular testing or an appreciable improvement in diagnostic performance.

Evaluation of pelvic washing specimens in patients with endometrial cancer: Cytomorphological features, diagnostic agreement, and pathologist experience.

BACKGROUND: Pelvic washings for patients with endometrial cancer is recommended but not used for staging. The International System for Reporting Serous Fluid Cytology (TIS) has standardized diagnostic categories, but the criteria remain incomplete. The 3 primary goals of this study were to 1) investigate features that distinguish atypical/indeterminate from malignant specimens, 2) measure the level of agreement between chart and reviewer diagnoses, and 3) determine whether the number of years in practice had an effect on the diagnoses rendered. METHODS: Pelvic washings and surgical pathology specimens for 52 patients with a chart diagnosis of atypical/indeterminate, suspicious, or malignant cytology and 52 age-matched controls with a negative chart diagnosis were included, reviewed blindly by 2 cytopathologists, and assigned a study diagnosis. Morphologic features were assessed. Agreement between original chart diagnoses and reviewer diagnoses were assessed as well as effect of years in practice. RESULTS: The overall cellularity in cell block (CB) slides for the malignant category was significantly increased compared with the atypical/indeterminate category (P < .0001). In addition, the number of atypical groups in ThinPrep for malignant washings was significantly increased compared with the atypical category (P < .001) and the negative and suspicious categories (P < .0001) in the CB. Overall agreement between the original and adjudicated diagnoses was high (γ = 0.983). There was no significant difference between diagnoses rendered and years in practice. CONCLUSION: The overall cellularity and number of atypical cells can be used to distinguish between malignant and atypical pelvic washing specimens. There is high reproducibility in the diagnostic categories and high agreement among pathologists, regardless of practice experience. These findings can help refine the criteria for TIS.

Thyroid carcinoma showing thymus-like differentiation (CASTLE): case report with cytomorphology and review of the literature.

Thyroid carcinoma showing thymus-like differentiation (CASTLE) is a rare tumor of the thyroid gland or adjacent soft tissues of the neck. Given the comparatively good prognosis of CASTLE, it is crucial to distinguish this neoplasm from other more aggressive thyroid neoplasms that can have similar or overlapping cytomorphological features. However, there is little information about the cytomorphology of CASTLE available in the literature. Here we report the cytomorphology and histology of thyroid CASTLE in a 52-year-old woman and present a review of the literature.

Use of the ThinPrep method in bile duct brushings: analysis of morphologic parameters associated with malignancy and determination of interobserver reliability.

Recent work suggests the ThinPrep method can improve diagnostic sensitivity and accuracy in bile duct brushings. However, the proportion of atypical and suspicious diagnoses remains high. The aim of this study was to identify the most useful morphologic features in ThinPrep bile duct cytology and evaluate interobserver reliability. We evaluated 100 bile duct brushings prepared by ThinPrep, all with either histology or long term clinical follow-up (55 malignant, 45 benign). Morphologic features were evaluated by four experienced cytopathologists blind to clinical information and follow-up diagnoses. These features included cellularity, blood or diathesis, mitoses, inflammation, three-dimensional groups, discohesive atypical cells, macronucleoli, well-defined cytoplasmic borders, and nuclear features of malignancy (nuclear membrance irregularity, chromatin clumping). The data were analyzed by intraclass correlation (ICC) and stepwise multiple logistic regression. Reviewers showed unanimous agreement in 29% of cases, one degree of disagreement in 58% of cases, and full disagreement in 13% of cases. Of benign cases, 38% were thought to be diagnostic of malignancy by at least one of the four reviewers. Sensitivity for the morphologic parameters varied from 18 to 67%; the highest sensitivity was for discohesive atypical cells, well-defined cytoplasmic borders, nuclear features of malignancy, and cellularity (67, 62, 51 and 46%, respectively). Specificity of parameters varied from 16 to 100%; the highest specificity was for mitoses, three-dimensional groups, nuclear features of malignancy, and macronucleoli (100, 98, 93, and 93%, respectively). Interobserver reliability (ICC) was very good for specimen cellularity (0.72) and nuclear features of malignancy (0.60). In logistic regression analysis, only nuclear features of malignancy and increasing patient age separated benign from malignant. On ThinPrep bile duct brushings, nuclear features of malignancy are most useful in distinguishing benign from malignant, and interobserver reliability for this parameter is very good. Discohesive atypical cells show moderate sensitivity and specificity, while three dimensional clusters and macronucleoli are specific but not sensitive for malignancy, and are not significant in multivariate logistic regression models. The relatively high proportion of benign cases thought to be diagnostic of malignancy by at least one reviewer argues for a consensus approach to this diagnosis.

The value of fluorescence in situ hybridization and polymerase chain reaction in the diagnosis of B-cell non-Hodgkin lymphoma by fine-needle aspiration.

CONTEXT: Molecular genetic analyses have been predicted to improve the diagnostic accuracy of fine-needle aspiration of B-cell non-Hodgkin lymphoma. OBJECTIVE: To determine the value of routine molecular genetic assays, polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH), in the diagnosis of B-cell non-Hodgkin lymphoma by fine-needle aspiration (FNA). DESIGN: A multiparametric method, including cytology, flow cytometry, PCR, and FISH, was prospectively evaluated in the diagnosis of B-cell non-Hodgkin lymphoma by FNA. Aspirates from 30 consecutive patients with suspected hematolymphoid malignancies were collected. All aspirates were triaged through a uniform program including cell-size analysis, B- and T-cell clonality studies, flow cytometric immunophenotyping, and bcl-1 and bcl-2 gene rearrangements by PCR and FISH. After completion of FNA evaluations, FNA results were compared with diagnoses from prior or subsequent surgical biopsies. RESULTS: Monoclonal B-cell populations were detected in 18 of 20 B-cell non-Hodgkin lymphomas by flow cytometry and PCR. bcl-1 gene rearrangement was detected in 2 of 2 cases of mantle cell lymphoma. bcl-2 rearrangement was detected in 5 cases including 4 of 4 low-grade follicular lymphomas and 1 transformed follicular lymphoma. By incorporating the results of molecular genetic and ancillary diagnostics, a definitive classification was reached in 12 cases of B-cell non-Hodgkin lymphoma by FNA, including all cases of low-grade follicular lymphoma (4/4) and mantle cell lymphoma (2/2) and approximately 50% of small lymphocytic lymphoma (2/4) and large B-cell lymphoma (4/8). Ten of the 12 cases with a final classification reached by FNA had either prior or follow-up surgical biopsies, and all 10 cases showed agreement between the diagnoses rendered on FNA and surgical biopsies. CONCLUSIONS: With proper handling and management of specimens, FNA can routinely provide samples adequate for molecular genetic studies, in addition to cytomorphology and flow cytometry, making it possible to consistently render accurate and definitive diagnoses in a subset of B-cell non-Hodgkin lymphomas. By incorporating FISH and PCR methods, FNA may assume an expanded role for the primary diagnosis of B-cell non-Hodgkin lymphoma.

Metastases in the pancreas from nonhematologic neoplasms: report of 20 cases evaluated by fine-needle aspiration.

We reviewed fine-needle aspiration (FNA) samples of metastatic tumor in the pancreas from nonhematologic neoplasms over a 5-year period. In 1,050 total procedures, 20 metastases were diagnosed: 9 renal-cell carcinomas (RCCs), 3 melanomas, 2 pulmonary small-cell carcinomas, 2 breast carcinomas, 1 prostate carcinoma, 1 colon adenocarcinoma, 1 pulmonary squamous-cell carcinoma, and 1 gastrointestinal stromal tumor. A wide range of latency from primary diagnosis was noted; the longest was RCC at 12.6 years (range, 5-28). Sites of involvement were: 13 heads, 4 bodies, and 3 tails. Eighteen cases presented as a solitary mass. The average size was 4.7 cm (range, 1.5-9.8), and a case of RCC (9.8 cm) was the largest. In seven cases, the clinical and radiographic impression was of a pancreatic primary. We conclude that metastases to the pancreas are rarely diagnosed by FNA and may clinically mimic a pancreatic primary.

Diagnostic impact of core-needle biopsy on fine-needle aspiration of non-Hodgkin lymphoma.

We retrospectively reviewed 74 fine-needle aspiration (FNA) cases of presumptive non-Hodgkin lymphoma (NHL). All the cases had cytology and core-needle biopsy and 53 cases had concurrent flow cytometric analysis. FNA (cytology and flow cytometry) and core-needle biopsy were evaluated independently. FNA was diagnostic of diffuse large B-cell lymphoma (DLBL) in 25% (13/53) of cases and small B-cell NHL in 15% (8/53) of cases, whereas core-needle biopsy was diagnostic of DLBL in 37% (27/74) of cases and small B-cell NHL in 8% (6/74) of cases. Subclassification of small B-cell NHL was reached in 3/6 cases by core-needle biopsy. Insufficient cases were observed in both FNA (47%; 25/53) and core-needle biopsy (28%; 21/74) groups. With the combination of FNA and core-needle biopsy, diagnostic cases of DLBL increased to 43% (32/74) and insufficient samples were reduced to 16% (12/74). There was no clear advantage in the diagnosis and classification of small B-cell NHL by adding core-needle biopsy to FNA (14%; 10/74). We conclude that core-needle biopsy is a useful adjunct to FNA in the diagnosis of DLBL and shall be encouraged. In small B-cell NHL, core-needle biopsy does not add to the diagnostic ability of FNA. Cases insufficient for diagnosis may be seen in both core-needle biopsy and FNA. A combined approach reduces the number of insufficient cases and is recommended in routine FNA practice.

Primary pancreatic lymphoma evaluated by fine-needle aspiration: findings in 14 cases.

Fine-needle aspiration (FNA) is a popular method for evaluating pancreatic lesions. There is considerable literature on FNA evaluation of primary pancreatic carcinomas, but few studies address the FNA diagnosis of primary pancreatic lymphoma. We reviewed 14 cases of atypical lymphoid processes diagnosed by FNA during a 5-year period, constituting 1.3% of a total of 1,050 pancreatic FNA cases. The diagnoses were as follows: 6 large B-cell lymphomas, 4 follicular lymphomas, 3 suggestive of lymphoma, and 1 unclassified B-cell lymphoma. Lymphoid neoplasms manifested in older people (mean age, 64.7 years) as a solitary mass in the pancreatic head, mimicking primary carcinoma. Clonality was confirmed by flow cytometry in 11 cases and immunohistochemical analysis on cell block material in 2. Obtaining diagnostic material often required several passes (average, 3.9 passes; range, 1-8 passes). We conclude that primary pancreatic lymphomas rarely are diagnosed by FNA, tend to be high grade, and clinically and radiographically might mimic primary carcinoma.