Cytotechnologist screening of fine‐needle aspiration specimens

Fine‐needle aspiration (FNA) is widely utilized due to its short turnaround time (TAT), diagnostic accuracy, and low cost. Controversy exists as to what role cytotechnologists should play in evaluation of FNAs. Some authorities believe all FNAs should be screened by cytotechnologists while others believe that cytotechnologist review is unnecessary. Sixty sequentially performed FNAs without initial review by cytotechnologists were selected from the files of the University of Utah, Department of Pathology. The slides were obtained along with the associated final diagnoses. The slides were reviewed by cytotechnologists given patient history and specimen site but were blinded to the initial pathologist's diagnoses. The initial cytopathologist's diagnoses and subsequent cytotechnologists' diagnoses were recorded and correlated. TATs for these cases were calculated and compared with TATs in a second set of randomly selected FNAs where cytotechnologists had initially screened the cases. Correlation of initial cytopathologists' diagnoses with those of cytotechnologists' revealed no instances where cytotechnologists identified diagnostically significant findings not noted by the original pathologist. TAT for the FNAs reviewed only by a cytopathologist averaged 25.9 hours with a mode of 6 hours. TATs for cases with initial cytotechnologist screening averaged 44.1 hours with a mode of 25 hours. Pre‐sign‐out screening of FNA specimens by cytotechnologists does not appear to increase detection of cytologic abnormalities. Cytotechnologist screening does substantially increased TAT from a mean of 26 hours to approximately 44 hours. Such an extensive delay may reduce the overall clinical utility of the FNA technique. Diagn. Cytopathol. 2014;42:606–608. © 2014 Wiley Periodicals, Inc.     

Papillary thyroid carcinoma with atypical histiocytoid cells on fine‐needle aspiration

Although papillary thyroid carcinoma (PTC) usually has classic cytological characteristics on fine‐needle aspiration (FNA), it can present rarely with aberrant features resembling those of histiocytes in a cystic nodule. The aim of the current study was to describe PTC with atypical histiocytoid cells and distinguish it from benign histiocytes. A retrospective computerized search for FNAs with atypical features suggestive of PTC and cystic degeneration was performed, and if available, the corresponding resection specimens were compared. Four cases met the criteria for FNAs and three had surgical pathology follow‐up, which showed PTC. One aspirate had some features typical of PTC, but the remaining FNAs had atypical histiocytoid cells, which had traits intermediate between those of PTC and histiocytes. Large cell size, pseudoinclusions, nuclear grooves, and multiple well‐defined vacuoles in atypical histiocytoid cells favor PTC over benign histiocytes. Ancillary immunocytochemical studies can also be useful in confirming the diagnosis. Histiocytic cells are frequently present in thyroid aspirates, and occasionally, they have atypical features that represent an unusual presentation of PTC. Closer examination of these cells can provide diagnostic clues for preventing false‐negative diagnosis of PTC. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Malignant teratoma of the thyroid: A difficult diagnosis by fine‐needle aspiration

Primary thyroid teratomas are rare, usually benign, and typically occur in children. We report the unusual occurrence of a malignant thyroid teratoma in a young man. Initial ultrasound and CT studies revealed an 8.5 heterogeneous mass involving the entire right thyroid lobe causing tracheal compression and deviation. Fine‐needle aspiration (FNA) revealed malignant cells with possible neuroendocrine features. Similar findings have been previously reported, with an occasional interpretation as possible medullary thyroid carcinoma. In no report, as with our case, has the correct diagnosis been suggested with FNA. The surgical specimen contained abundant primitive neuroepithelium with a very minor component of mature ectodermal tissue in one area. Like this case, an abundance of immature neuroepithelium has been reported in essentially all previous reports of primary malignant thyroid teratoma, sometimes creating a challenge to find another type of germ cell tissue. Array comparative genomic hybridization studies in this case revealed a markedly complex karyotype including gain of chromosome 12 and loss of 17p. Amplification of MYCN, EWSR1 rearrangement and isochromosome 12p were not identified, providing no evidence for neuroblastoma or Ewing sarcoma/peripheral neuroectodermal tumor, both of which have also rarely been reported as primary thyroid tumors. With the use of cisplatinum‐based chemotherapy combined with radiation, survival times have increased dramatically. Our patient is now disease free and back to his normal activities after relatively short follow‐up. Although rare, it is important to be aware that teratomas may present as a thyroid nodule. Recognition by FNA is challenging, and requires multiple modalities for full identification.     

Medullary thyroid carcinoma presenting as rectangular cell type on fine‐needle aspiration

Medullary thyroid carcinoma typically presents as dyscohesive plasmacytoid, spindled, or polygonal cells on fine‐needle aspiration smears. We recently encountered a case of sporadic medullary thyroid carcinoma that presented as a hypercellular aspirate composed of cohesive aggregates of rectangle‐shaped cells. The case was mistakenly reported as a hypercellular follicular neoplasm on cytology. Subsequent thyroidectomy revealed medullary carcinoma. We draw attention to this distinctive rectangular cell type as an additional morphology for medullary thyroid carcinoma. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Laryngeal chondrosarcoma mimicking medullary thyroid carcinoma on fine‐needle aspiration cytology: A case report of a diagnostic pitfall

Chondrosarcoma (CS) of larynx is a rare laryngeal tumor accounting about 1% of laryngeal malignancies. When CS arises from thyroid cartilage, it may clinically present as a thyroid nodule. Here we report a rare case of CS of thyroid cartilage misinterpreted as medullary thyroid carcinoma. The main aim of this case report is to emphasize the important role of accurate clinical history, appropriate physical examination, and proper localization of the tumor and clear definitive imaging in conjunction with interpretation of cytologic smears. When any of these roles are unclear, it may result in misinterpretation of the cytologic smears. In these unusual circumstances, when cytomorphologic features does not completely fit an entity, communication with the physician and the consideration of a broad differential diagnoses in the head and neck pathology may lead to correct diagnosis and avoid diagnostic pitfalls. Also in certain conditions, ancillary studies including laboratory tests are necessary for definitive classification.     

Comparison of cytological results obtained by repeated US‐guided fine‐needle aspiration biopsies of thyroid nodules: Focus on the rate of malignancy and diagnostic concordance

The debate still continues on the repeated fine‐needle aspiration biopsies (FNABs) for thyroid nodule in clinical practice. In this study, we determined the rate of cytological change to malignancy and the diagnostic concordance of repeated FNABs when the same nodules were targeted under US‐guidance. We retrospectively reviewed data for 187 thyroid nodules (173: twice, 14: three times) from 160 patients who underwent repeated US‐guided FNABs, which were performed by one skilful radiologist targeting for the same nodules at a mean interval of 7.5 months. Their initial cytological findings were compared with second or third results and histopathologic follow‐up. The initial FNABs findings of 187 nodules were unsatisfactory, benign, and indeterminate in 56, 52, and 79 cases, respectively. The rate of a second cytological diagnosis changed to malignancy was significantly higher in the unsatisfactory aspirates (10.7%; 6/56), when compared with those of the benign (0.0%; 0/52) or of indeterminate aspirates (3.8%; 3/79) (P = 0.022). However, there was no change to malignancy at third cytological findings of all 14 nodules. After the second US‐guided FNABs, 30.8% (16/52) of the initially diagnosed as benign aspirates were reclassified as indeterminate, while 26.6% (21/79) of the initially diagnosed as indeterminate were reclassified as benign. In conclusion, to identify malignancies, repeated US‐guided FNABs are recommended for thyroid nodules initially classified as unsatisfactory aspirates. However, although US‐guidance is applied, a discrepancy might be unavoidable in the cytological interpretation of the nodules classified as benign or as indeterminate aspirates because of overlapping cytological criteria. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.     

Diagnostic value of B‐RAFV600E in difficult‐to‐diagnose thyroid nodules using fine‐needle aspiration: Systematic review and meta‐analysis

Fine‐needle aspiration (FNA) is routinely used in the preoperative evaluation of thyroid nodules. However, approximately 5–20% of thyroid nodules are considered indeterminate or suspicious cases that do not meet clinical standards. The B‐RAF^V600E mutation has been reported in FNA specimens. We conducted a systematic review to evaluate the diagnostic value of testing for B‐RAF^V600E in thyroid nodules that are difficult to diagnose by FNA. A systematic literature search was performed from January 1, 2002 to June 30, 2012. Articles were obtained by searching two electronic databases (MEDLINE and EMBASE), hand searching selected journals, and contacting authors. Article quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. Sensitivity, specificity, and other measures of accuracy were pooled using random effects models. Summary receiver operating characteristic (SROC) curves were used to summarize overall diagnostic accuracy. A total of 16 studies incorporating 1131 patients were included in a meta‐analysis on diagnostic accuracy of B‐RAF^V600E tests. Pooled sensitivity was 0.60 (95% confidence interval [CI]: 0.556–0.634), pooled specificity was 0.99 (95% CI 0.976–0.997), and the area under the curve of the SROC curve was 0.8376. Q index value was 0.7696. Our data suggest a potentially useful adjunct to evaluating thyroid nodules that are difficult to diagnose. The B‐RAF^V600E test has a high positive predictive value and could help clinicians formulate a more individualized treatment schedule. When supplemented with other noninvasive test methods, the B‐RAF^V600E test could be a powerful adjunct with extensive clinical applications. Diagn. Cytopathol. 2014;42:94–101. © 2013 Wiley Periodicals, Inc.     

Cytomorphologic features of fine‐needle aspiration of liposarcoma

The cytomorphologic features of fine‐needle aspirates (FNA) of liposarcomas have not been fully characterized. In the current study, we attempted to identify cytological attributes of liposarcoma in FNA. Twelve FNAs of histologically proven liposarcomas were used for this study. They included 10 myxoid and two well‐differentiated liposarcomas. Four cytological criteria were chosen for evaluation. These included a complex capillary network, increased cellularity, the presence of a metachromatic stroma for myxoid liposarcoma, and finally the identification of lipoblasts. Eighteen FNAs of lipomas and 17 FNAs of nonlipomatous soft‐tissue sarcomas were used as controls for evaluation of the same features. The diagnosis of liposarcoma had been rendered on FNA in 7 cases (58%). The diagnosis was suggested in 3 cases (25%), and a suggestion of sarcoma was rendered in 2 cases. Complex capillary networks were identified in 9 of 12 cases (75%); this was seen in 8 of the 10 myxoid liposarcomas and 1 of the 2 well‐differentiated neoplasms. Increased cellularity was seen in 7 of 12 cases (58%), metachromatic stroma was seen in 3 of 12 cases (25%), and lipoblasts were identified in 4 of 12 cases (33%). None of the lipomas or sarcomas exhibited a complex capillary network. When capillaries were identified in lipomas, they were straight, with minimal branching. The lipomas did not show evidence of increased cellularity in any cases. Metachromatic stroma was more frequently seen in the nonlipomatous sarcomas than in the liposarcomas. No lipoblasts were identified in any of the control FNAs. Diagn. Cytopathol. 1999;20:67–69. © 1999 Wiley‐Liss, Inc.     

Mucinous breast carcinoma metastatic to thyroid gland: Report of a case diagnosed by fine‐needle aspiration cytology

Mucinous breast cancer is a slow‐growing neoplasm, which has fewer lymph node metastases and favorable prognosis compared with invasive breast cancer no special type. The hematogenous spread of breast mucinous carcinoma is very rare. Though breast cancer involving thyroid has been reported before, there is still no report about thyroid metastatic breast mucinous carcinoma in the literature. Recently by performing thyroid fine‐needle aspiration, a 58‐year‐old woman who had breast cancer 13 years ago was diagnosed as thyroid metastatic mucinous breast carcinoma, cellular variant with neuroendocrine differentiation. For this patient, the thyroid was the only involved site without widespread metastatic diseases, so thyroidectomy and the right cervical lymph nodes dissection were performed to make better survival. As a result, the patient had not shown any signs of recurrence 9 months after the thyroid surgery.