Cytologic features of metastatic papillary thyroid carcinoma in cervical lymph nodes

OBJECTIVE: To elucidate the cytologic characteristics of metastatic papillary thyroid carcinoma (PTC) in cervical lymph nodes and the differences in cervical lymph nodes from those of stage I (intrathyroidal) PTC. STUDY DESIGN: Forty-seven cases of papillary thyroid carcinoma with cervical lymph node metastasis (group A) and 38 cases of intrathyroidal papillary carcinoma (group B) were included in this study. Preoperative fine needle aspiration cytology (FNAC) examination was performed on enlarged cervical lymph nodes (47 cases, group A) and enlarged thyroid nodules (13 cases, group A, and 38 cases, group B). All the cases were surgically excised and pathologically verified. The cytologic smears were reviewed and analyzed. RESULTS: The cytologic characteristics of metastatic PTC in cervical lymph nodes displayed a higher frequency of foamy macrophages (51.1% vs. 26.3%) and a lower frequency of distinct cell borders (38.3% vs. 71.1%) than those of stage I PTC. Metastatic PTC in cervical lymph nodes also had a higher frequency of cystic degeneration (44.7% vs. 5.3%) than intrathyroidal lesions. In 1 of the 47 cases with lymph node metastasis, the aspirate contained macrophages but no tumor cells. CONCLUSION: FNAC was useful in the diagnosis of metastatic PTC in cervical lymph nodes. However, because cystic degeneration appeared frequently, FNAC combined with thyroid ultrasonography to find the primary lesion is necessary in this situation.     

Ultrasonographic Differentiation of Cervical Lymph Nodes in Patients with Papillary Thyroid Carcinoma After Thyroidectomy and Radioiodine Ablation: A Prospective Study

ObjectiveThe objective of the present study was to validate an ultrasound (US) classification of cervical lymph nodes (LNs) in patients with papillary thyroid cancer (PTC) after thyroidectomy and radioactive iodine (¹³¹I) ablation.MethodsWe performed a prospective study in which the patients were submitted to thyroidectomy and ¹³¹I ablation and then followed until neck US revealed LN(s) ≥ 5 mm. A total of 288 LNs from 112 patients with PTC were evaluated. Patient management was based on LN characteristics grouped according to the classification system studied here.ResultsThe presence of microcalcifications and/or cystic degeneration of cervical LNs were highly suggestive of a metastatic etiology (specificity of 99.4%). In contrast, the most sensitive finding for LNs affected by PTC was the absence of an echogenic hilum (sensitivity of 100%). In the absence of these findings (microcalcifications, cystic degeneration, echogenic hilum), a metastatic etiology was the most likely in the case of a round LN (specificity of 89%). The differentiation of a spindle-shaped LN without a visible hilum by Doppler analysis permitted us to dichotomize an initial probability of metastases of 13% in 25% (with peripheral vascularization) versus 3.3% (without peripheral vascularization).ConclusionsOur results confirm that the classification proposed for cervical LNs in patients with PTC is valid for determining patient management following initial therapy. (Endocr Pract. 2014;20:293-298)     

Efficiency of a Preoperative Axillary Ultrasound and Fine-Needle Aspiration Cytology to Detect Patients with Extensive Axillary Lymph Node Involvement

Background

Recent studies have demonstrated that axillary lymph node dissection (ALND) does not affect patient survival, even in those with one or two positive sentinel lymph nodes (SLNs). On the other hand, patients with 3 or more metastatic lymph nodes are eligible for chemotherapy. Therefore, it is crucial to identify a priori patients at risk of having a high number of metastatic axillary lymph nodes for their surgical and/or clinical management. Ultrasound (US) guided Fine-Needle Aspiration (FNA) has been proven to be a useful and highly specific method for detecting metastatic axillary lymph nodes. However, only one recent study has evaluated the efficiency of this method in identifying patients with high metastatic nodal involvement. Our aim was to validate US-guided FNA as a reliable method to discriminate a priori patients with >3 metastatic lymph nodes.

Methods

A retrospective series of 1287 breast cancer patients who underwent a simultaneous preoperative breast and axillary US to stage their axilla was collected. A total of 365 patients, with either positive SLNs (278) or positive axillary lymph nodes detected via US-guided FNA (87), underwent ALND. In these two subgroups, we compared the number of metastatic lymph nodes in the axilla.

Results

The number of metastatic axillary lymph nodes in patients who underwent US-guided FNA was significantly higher (63% had >3 metastatic lymph nodes) than that in patients with SLNs positive for micro- or macrometastases (3% and 27%, respectively) (P<0.001, χ ² = 117.897).

Conclusions

Preoperative axillary US-guided FNA could act as a reliable tool in identifying breast cancer patients with extensive nodal involvement.     

Fine needle aspiration cytodiagnosis of nasopharyngeal carcinoma in cervical lymph nodes. A study of 40 cases

The cytologic features of fine needle aspiration (FNA) samples of 40 metastatic nasopharyngeal carcinomas in cervical lymph nodes were reviewed. FNA was performed with 21-gauge or 23-gauge needles; the FNA smears were stained with the Papanicolaou stain or with hematoxylin and eosin. Several typical cytologic features were noted. All cases showed the presence of clusters of cohesive tumor cells, most of which were undifferentiated. Medium-sized oval vesicular nuclei were present in 85% of the cases; all cases had prominent nucleoli. The cytoplasm was generally pale, with ill-defined boundaries in 87.5% of the cases. Mitoses were present in 75% of the cases. Mature lymphocytes were intermingled with tumor cells in all cases. The cytologic features correlated with the histologic features in surgical biopsies of the nasopharynx and lymph nodes. The results show that FNA of cervical lymph nodes can aid in the diagnosis of otherwise occult nasopharyngeal carcinoma and in detecting residual or recurrent nodal disease in patients with nasopharyngeal carcinoma who had undergone treatment.     

Atypical epithelial cells, cannot exclude papillary carcinoma, in fine needle aspiration of the thyroid

OBJECTIVE: Atypical epithelial cells, cannot exclude papillary thyroid carcinoma (AEC-PTC), in fine needle aspiration (FNA) of the thyroid is a controversial diagnostic category that might cause a dilemma in patient management. STUDY DESIGN: Eighty-eight thyroid FNA specimens from 86 patients with a diagnosis of AEC-PTC were retrieved from our files in a 10-year period from December 1996 to December 2006. Of the 86 patients, 57 had follow-up histologic diagnoses and were included in this study. The cytologic and histologic materials were reviewed and correlated. RESULTS: Of the 57 patients, all had cytologic atypical features suggestive of PTC. Twenty-five cases of PTC were identified at surgery (44%). Review of the cytologic materials identified the following cytologic features, either alone or in combination strongly associated with PTC at resection: rare intranuclear cytoplasmic invagination (INCI), squamoid cytoplasm and psammoma bodies. CONCLUSION: The most common reasons for rendering the diagnosis of AEC-PTC in FNA of thyroid include rare atypical cells in a cystic thyroid nodule or a background of Hashimoto's thyroiditis. The cytologic features of LNCI, squamoid cytoplasm and psammoma bodies should alert the pathologist. Focal cytologic features of PTC in FNA samples are strongly associated with papillary carcinoma on resection.     

Parotid metastasis of Merkel cell carcinoma in a young patient with ectodermal dysplasia. Diagnosis by fine needle aspiration cytology and immunocytochemistry.

Fine needle aspiration (FNA) biopsy was performed on an intraparotid lymph node metastasis of a Merkel cell carcinoma of the eyelid in a 15-year-old girl with antecedent ectodermal dysplasia syndrome. The cytologic appearance of the aspirate and the results of immunocytochemical typing of intermediate filaments on the FNA smears provided a definitive diagnosis. The Romanowsky stain provided an excellent delineation of paranuclear intracytoplasmic "buttons," which appeared to contain both cytokeratin and neurofilaments by immunocytochemical studies. These findings confirm previous data emphasizing the role of light microscopic observations, supplemented by proper immunocytochemical investigations, in the differential diagnosis of metastatic Merkel cell carcinoma in fine needle aspirates.     

Adenoid cystic carcinoma metastatic to the kidney: a case report

BACKGROUND: Fine needle aspiration (FNA) of kidney lesions under image control is widespread and well documented. This technique is essential in preoperative differential diagnosis of solid and cystic benign or malignant lesions of the kidney. Kidney metastases are not frequent and are usually described in terminally ill patients, by which time the illness is extended, or in autopsy findings. A small percentage of kidney lesions are metastatic tumors from a known primary location and are found in oncologic controls. CASE: We present a case of metastasis to the kidney from a palate adenoid cystic carcinoma (ACC) diagnosed 14 years previously. The patient presented with a kidney cystic lesion. FNA revealed the characteristic features of an ACC. CONCLUSION: We emphasize the usefulness of FNA in the differential diagnosis of renal metastatic tumors. The characteristic cytologic morphology of ACC permits differentiation between a primary renal tumor and a metastatic process.     

Testicular germ cell tumors. Classification based on fine needle aspiration biopsy

Fine needle aspiration (FNA) biopsy was performed preoperatively on 13 patients with testicular germ cell tumors. The cytologic typing of the tumors was based on the presence or absence of seminoma, embryonal carcinoma, yolk-sac tumor, choriocarcinoma and teratoma in the aspirate. The cytologic findings showed good agreement with the histologic findings. Only four cases showed a single type of tumor; the other nine cases showed as many as four different tumor components. A few characteristic cytologic features proved to be sufficient for tumor typing; this suggests that FNA biopsy cytology can also be useful in identifying metastatic germ cell tumors in extra-gonadal sites.     

The diagnostic value of thyroglobulin concentration in fine-needle aspiration of the cervical lymph nodes in patients with differentiated thyroid cancer

INTRODUCTION: Recurrent differentiated thyroid cancer generally occurs first in the neck. Ultrasound is sensitive in detecting enlarged cervical lymph nodes but is not specific enough. Ultrasound-guided fine-needle biopsy increases the specificity but still may fail to detect a recurrence of the disease in the cystic metastatic lymph nodes. The aim of the study was to estimate the value of Tg concentration in the needle washout after fine-needle aspiration of suspicious lymph nodes. MATERIAL AND METHODS: The 105 patients studied had presented one or more enlarged suspicious cervical lymph nodes. All had undergone total thyroidectomy and (131)I ablative therapy. Serum thyroglobulin (Tg) concentration was within the 0.15-711.5 ng/ml range (mean 22.24 ng/ml) and Tg recovery range 94-100%. The positive Tg washout concentration cut-off value was established as equal to the mean plus two standard deviations of the Tg washout concentration of patients with negative cytology. RESULTS: Lymph node involvement was diagnosed by cytology in 15 patients and in 28 lymph nodes. Positive Tg washout concentration was found in 22 patients and in 48 lymph nodes. All the lymph nodes which turned out to have positive cytology had a positive Tg washout concentration. All lymph nodes with positive cytology were positive in pathology. Seven patients and 20 lymph nodes with negative cytology were positive in the Tg washout concentration test. All but one patients and all but two lymph nodes with a positive Tg washout concentration had positive pathology. CONCLUSIONS: 1. Ultrasound-guided fine-needle biopsy is not sensitive enough to detect all metastatic lymph nodes. 2. The Tg washout concentration test is 100% sensitive in the detection of metastatic lymph nodes. 3. Cytology in ultrasound- guided fine-needle biopsy is 100% specific. 4. The Tg washout concentration test carries a risk of false-positive results. 5. Both methods should be used for early detection of metastatic lymph nodes in patients with differentiated thyroid cancer.     

Computerized morphometric image analysis of cytologic nuclear parameters in breast cancer

The value of nuclear morphometry in the preoperative fine needle aspiration (FNA) cytologic diagnosis of mammary lesions was investigated and correlated with the lymph node status of the patients. The subjects consisted of four groups of patients: 49 with invasive ductal carcinomas (18 with no positive nodes, 16 with one to three positive nodes and 15 with four or more positive nodes) and 14 patients with benign lesions. The FNA specimens were smeared onto slides and stained by the May-Grünwald-Giemsa technique. The area, perimeter and maximum diameter of 100 randomly chosen nuclei were both measured with the IBAS image analysis system and semiquantitatively estimated with an eyepiece micrometer. For all three parameters, significant differences were found between benign and malignant lesions. The mean nuclear perimeter allowed the morphometric discrimination between all four groups with statistical significance; nuclear area and maximum diameter did not discriminate patients with invasive carcinoma and one to three positive nodes from those with no positive nodes or more than three positive nodes. Morphometry proved to be far superior to eyepiece measurements with respect to accuracy and reproducibility of the results. The results suggest that nuclear perimeter can be used as an additional parameter not only for the FNA cytologic diagnosis of breast cancer, but also for the estimation of patients' prognosis.     

Fine needle aspiration of metastatic and hematologic malignancies clinically mimicking pancreatic carcinoma.

The fine needle aspiration (FNA) cytology findings in 19 cases of hematopoietic and metastatic neoplasms that radiographically mimicked primary pancreatic carcinoma are reported. These cases represented 11% of 176 malignant diagnoses in a series of 304 pancreatic FNAs. The cytologic diagnoses included 7 non-Hodgkin's lymphomas, 2 Hodgkin's lymphomas, 6 small cell carcinomas (4 lung, 1 gallbladder, 1 skin), 3 squamous cell carcinomas (2 cervix, 1 esophagus) and 1 hepatocellular carcinoma. In six cases the pancreatic lesion was the initial presentation of malignant disease. These included five lymphomas, which probably involved peripancreatic lymph nodes, and a metastatic small cell carcinoma of pulmonary origin. Recognition of unusual morphologic features of pancreatic carcinoma raised the possibility of extrapancreatic malignancies. Electron microscopy and immunocytochemistry performed on FNA specimens were helpful in selected cases. The FNA diagnosis of hematopoietic and metastatic neoplasms that clinically mimic pancreatic carcinoma prompts appropriate clinical studies and treatment and eliminates the need for open pancreatic biopsy and/or resection.     

Hyalinizing trabecular tumor in a background of lymphocytic thyroiditis: a challenging neoplasm of the thyroid

ObjectiveTo describe a case of hyalinizing trabecular tumor (HTT) in a background of lymphocytic thyroiditis that was misdiagnosed as papillary thyroid carcinoma (PTC) based on fine-needle aspiration (FNA) cytologic findings and overtreated with total thyroidectomy.MethodsWe present a case report, including the imaging and pathologic findings, of a 68-year-old woman who presented with a multinodular goiter that was suspicious for PTC.ResultsOn the basis of FNA cytologic findings, she underwent a total thyroidectomy, and histologic examination of the thyroid gland revealed HTT in a background of lymphocytic thyroiditis. Radioiodine treatment was not administered because of the tumor’s low risk profile. No metastatic foci were established under nonsuppressive levothyroxine therapy after 3 years of follow-up.ConclusionsHTT is a challenging entity because of the uncertainty of its nature, the diagnostic challenges,and the mimicry of other types of thyroid tumors. In order to avoid overtreatment, endocrinologists and thyroid surgeons should be aware of the features of HTT, and suspicious cases should be evaluated by experienced cytopathologists. (Endocr Pract. 2011;17:e140-e143)     

Positive Thyroid Peroxidase Antibody and Thyroglobulin Antibody are Associated With Better Clinicopathologic Features of Papillary Thyroid Cancer

ObjectiveTo compare the thyroid autoantibody status of patients with papillary thyroid cancer (PTC) and benign nodular goiter as well as possible associations between thyroid autoantibodies and clinicopathologic features of PTC.MethodsA total of 3934 participants who underwent thyroidectomy were enrolled in this retrospective study. Patients were divided into PTC and benign nodule groups according to pathological diagnosis. Based on the preoperative serum antibody results, PTC patients were divided into thyroid peroxidase antibody (TPOAb)-positive, thyroglobulin antibody (TgAb)-positive, dual TPOAb- and TgAb-positive, or antibody-negative groups.ResultsOf the 3934 enrolled patients, 2926 (74.4%) were diagnosed with PTC. Multivariate regression analyses suggested that high thyroid-stimulating hormone levels (adjusted odds ratio [OR] = 1.732, 95% CI [1.485-2.021], P < .001), positive TgAb (adjusted OR = 1.768, 95% CI [1.436-2.178], P < .001), and positive TPOAb (adjusted OR = 1.452, 95% CI [1.148-1.836], P = .002) were independent risk factors for predicting malignancy of thyroid nodules. Multinomial multiple logistic regression analyses indicated that positive TPOAb alone was an independent predictor of less central lymph node metastasis in PTC patients (adjusted OR = 0.643, 95% CI [0.448-0.923], P = .017), whereas positive TgAb alone was significantly associated with less extrathyroidal extension (adjusted OR = 0.778, 95% CI [0.622-0.974], P = .028). PTC patients with dual-positive TPOAb and TgAb displayed a decreased incidence of extrathyroidal extension (adjusted OR = 0.767, 95% CI [0.623-0.944], P = .012) and central lymph node metastasis (adjusted OR = 0.784, 95% CI [0.624-0.986], P = .037).ConclusionAlthough preoperative positive TPOAb and TgAb are independent predictive markers for PTC, they are also associated with better clinicopathologic features of PTC.     

Management of Patients With Low-Risk Papillary Thyroid Carcinoma

ObjectiveTo define a rational, cost-effective, simple approach to managing most patients with papillary thyroid cancer (PTC) who are at low-risk of either cause-specific mortality or tumor recurrence.MethodsTaking advantage of the collective experience of a cohort of 2512 patients with PTC who had initial definitive treatment at the Mayo Clinic in Rochester, Minnesota, between 1940 and 2000, a 5-step approach to the management of low-risk PTC has been devised. This program is based on appropriate preoperative ultrasound localization of neck disease and potentially curative surgery consisting of near-total or total thyroidectomy, with appropriate neck nodal exploration and resection.ResultsThe emphasis of the present program is on the extent of initial surgery, where optimal care is ascribed to a near-total thyroidectomy with curative intent and appropriate neck nodal resection as predicated by appropriate preoperative ultrasonography evaluation of regional lymph nodes. Radioiodine remnant ablation (RRA) is not applicable to patients with PTC who are defined on the day of definitive initial surgery to be at low risk as defined by a metastasis, age, completeness of resection, invasion, and size (MACIS) score of less than 6.ConclusionThe outlook for patients with low-risk PTC is very optimistic, with rates at 30 postoperative years of only 1% for cause-specific mortality and less than 15% for tumor recurrence at any site. The long-term results obtained by potentially curative bilateral resection, appropriate regional lymph nodal excision, and selective use of RRA are excellent. Realistically improving these acceptably low rates for cause-specific mortality and tumor recurrence may be difficult. (Endocr Pract. 2007;13:521-533)     

Primary osteogenic sarcoma of the breast: cytomorphologic study of 3 cases with histologic correlation

BACKGROUND: Primary osteogenic sarcomas of the breast are extremely rare neoplasms. The histologic and cytologic features are comparable to those of their soft tissue and skeletal counterparts. To assess the utility of fine needle aspiration (FNA) in preoperative identification of osteogenic sarcomas, we retrospectively reviewed the FNA findings of 3 cases diagnosed in our hospital over 2 1/2 years. CASES: Three women, aged 48, 55 and 76 years, presented with a palpable lump of a few months' duration in their breasts. FNA was indicative of malignancy, and mastectomy with ipsilateral axillary lymph node dissection was performed. The cytologic features were of hypocellular or hypercellular smears with pleomorphic cells; scarce or abundant metachromatic amorphous material, suggestive of osteoid; osteoclast-like giant cells; and stromal fragments. CONCLUSION: Although cytologic features can be suggestive of osteosarcoma in the appropriate clinical setting, prompt preoperative diagnosis of malignancy in FNA samples of these tumors can avoid undertreatment, because mammographic and clinical findings are in many cases confused with the features of a benign lesion, more specifically calcified fibroadenoma.     

Diagnosing Kikuchi disease on fine needle aspiration biopsy: a retrospective study of 44 cases diagnosed by cytology and 8 by histopathology.

OBJECTIVE: To study the accuracy of fine needle aspiration (FNA) diagnosis of Kikuchi lymphadenitis (KL). STUDY DESIGN: Retrospective review of all cases of FNA biopsy of lymph nodes in which KL was diagnosed or suggested. False positive cases were studied. Cases of KL diagnosed by histopathology were examined for the false negative rate of FNA diagnosis. RESULTS: Forty-four cases of KL diagnosed or suggested by FNA were found. Five of eight cases were confirmed on lymph node excision. The false positive rate was 37.5%. One case was nonspecific reactive changes. Two cases were proven to be tuberculous lymphadenitis by culture. Eight cases of KL diagnosed by lymph node excisional biopsy had prior FNA. Four were diagnosed as or suspected to be KL. The false negative rate was 50%. CONCLUSION: The overall accuracy of FNA diagnosis of KL was 56.25%. Detailed study offalse positive cases and knowledge of other conditions suggested that overreliance on certain cytologic features and the morphologic erlap between KL and tuberculous lymphadenitis could have been the reasons for the inaccuracies.     

Prognostic Value of Lymph Node Uptake on Pretreatment F-18 FDG PET/CT in Patients with N1B Papillary Thyroid Carcinoma

Objective: The aim of this study was to investigate the prognostic value of metabolic characteristics of metastatic lymph node (LN) using pretreatment F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for patients with papillary thyroid carcinoma (PTC) and metastatic lateral LN (N1b).Methods: Ninety-six PTC patients (female:male = 72:24; median age, 44.5 years) with pathologic N1b who underwent pretreatment FDG PET/CT, total thyroidectomy, and radioactive iodine ablation were retrospectively reviewed. To predict responses to initial therapy and recurrence, clinicopathologic factors and metabolic parameters were reviewed, such as sex, age, tumor size, extranodal extension, number and ratio of metastatic LNs, serum thyroglobulin, and maximum standardized uptake value (SUVmax).Results: Among the 96 PTC patients, 81 (84.4%) were classified into the acceptable response (58 excellent; 23 indeterminate) and 15 (15.6%) into the incomplete response (8 biochemical incomplete; 7 structural incomplete) by the 2015 American Thyroid Association management guideline for differentiated thyroid carcinoma. The multivariate analysis showed that SUVmax of N1b (P = .018), pre-ablation stimulated thyroglobulin level (P = .006), and the ratio of metastatic LNs (P = .018) were related to incomplete response. The cutoff value of each variable was determined by receiver operating characteristic analysis. Nine (9.4%) patients experienced recurrences (median follow-up: 50 months). The Kaplan-Meier analysis revealed that SUVmax of N1b (cutoff value: 2.3; P = .025) and ratio of metastatic LNs (cutoff value: 0.218; P = .037) were significant prognostic factors for recurrence.Conclusion: High SUVmax of N1b cervical LN on pretreatment FDG PET/CT could predict incomplete responses to initial therapy and recurrence in patients with N1b PTC.Abbreviations: ATA = American Thyroid Association; DTC = well-differentiated thyroid carcinoma; FDG = F-18 fluorodeoxyglucose; IQR = interquartile range; LN = lymph node; N1b = metastatic lateral cervical lymph node; PET/CT = positron emission tomography/computed tomography; PTC = papillary thyroid carcinoma; RAI = radioactive iodine; ROC = receiver operating characteristic; SUVmax = maximum standardized uptake value; Tg = thyroglobulin; USG = ultrasonography     

Fine needle aspiration of follicular variant of papillary thyroid carcinoma presenting with pleural effusion: a case report

BACKGROUND: Malignant pleural effusion in association with mesothelioma, bronchogenic carcinoma and breast carcinoma is common, although less frequently reported with other malignancies. We report a follicular variant of papillary thyroid carcinoma (FVPTC), diagnosed on fine needle aspiration cytology (FNAC) of thyroid and lymph nodes and subsequently proved to have metastasized to the pleural cavity. CASE: A 46-year-old man presented with history of breathlessness, thyroid swelling, pleural effusion and bilateral cervical lymphadenopathy. FNAC of the thyroid swelling and the lymph nodes showed features of FVPTC with cervical lymph node metastasis. Pleural fluid examination led to suspicion of pleural involvement by metastatic deposit, confirmed by subsequent pleural biopsy. CONCLUSION: Thyroid malignancies presenting with pleural effusion are rare. In this case, although pleural fluid cytology suggested involvement of pleura, a definitive diagnosis could be rendered only on pleural biopsy. An ancillary aid, such as immunocytochemistry, could have helped establish pleural involvement on routine pleural fluid cytology alone. This case emphasizes the possible existence of rare cases of FVPTC that may be associated with a dismal prognosis. In our case, initial diagnosis of FVPTC could be made only on correlating FNA features of thyroid aspirate with those of lymph node aspirate.     

Intrathyroidal Ectopic Thymic Tissue Mimicking Thyroid Cancer in Children

ObjectiveTo increase awareness of the important differential diagnosis between thyroid cancer and intrathyroidal ectopic thymic tissue when performing neck ultrasound (US) in pediatric patients.MethodsWe report 2 cases of intrathyrodal thymic tissue that were initially referred as possible papillary thyroid cancer (PTC). US and cytologic features of these lesions are described, and the distinguishing US characteristics of intrathyroidal thymic tissue versus PTC are discussed.ResultsTwo pediatric patients who underwent thyroid US were diagnosed with thyroid nodules suggestive of PTC. The suspected lesions in both patients exhibited an echo texture identical to the normal thymus gland. Fine-needle aspirate (FNA) biopsy of the nodule in the first case revealed numerous lymphocytes with positive immunocytochemical staining for CD3, confirming a T cell phenotype. The second patient underwent follow-up US imaging 8 months later that showed stability of the intrathyroidal nodule.ConclusionIntrathyroidal ectopic thymic tissue can be mistaken for PTC as both conditions have similar US features. Increased awareness of this unique mimicry may help to avoid unnecessary invasive investigations and surgery in these young patients. (Endocr Pract. 2014;20: e241-e245)     

Fine needle aspiration in a malignant lymphoepithelial lesion: a case report

BACKGROUND: A primary malignant lymphoepithelial lesion (MLEL) of the salivary gland is a rare tumor. Though histologic morphology of this lesion is well documented, the cytologic findings regarding fine needle aspiration (FNA) are not yet well described. CASE: A 56-year-old Thai woman from Udonthanee was admitted to Srinagarind Hospital with a 2-year history of a painless mass in the left parotid gland. FNA of the left parotid mass was performed, and findings suggestive of malignancy were discovered. A wide local excision was performed 1 year later, and MLEL with metastasis to the regional lymph nodes was diagnosed by histopathology. CONCLUSION: We report our first experience of cytologic findings from FNA of histologically diagnosed MLEL. The aspirate comprised groups of cohesive and isolated malignant epithelials with a background of numerous lymphocytes. Cytotechnologists should be reminded of this rare lesion when confronted with a lymphocytic background from either benign or malignant lesions.