Langerhans cells proliferation in ectopic micronodular thymoma with lymphoid stroma: a case report

Ectopic micronodular thymoma (MNT) is a rare tumor. We described a 76-year-old woman, who was referred to our institutional for a mass in the left cervical region. The Magnetic Resonance Imaging (MRI) scan showed a 3.7 cm × 1.7 cm × 2.0 cm mass. The neoplasm was composed of epithelial tumor cells arranged in a micronodular growth pattern set in a stroma showing lymphoid hyperplasia with germinal centers. Immunohistochemical studies showed that the neoplastic epithelial cells were reactive for AE1/AE3, CK5/6, P63, and the lymphoid component to be of mixed B- and immature T-cell lineage. Langerhans cells were confirmed within epithelial nodules for the first time with langerin, S-100, CD1a expression. We report a case of cervical ectopic MNT to emphasize the langerhans cells proliferation and the histopathologic features and differential diagnosis of the rare lesion to promote a better and broader understanding of this less understood subject.

Relationship between VEGF protein expression and lymph node metastasis in papillary thyroid carcinoma among Asians: a meta-analysis

We carried out the current meta-analysis of relevant cohort studies in an attempt to investigate the relationships between vascular endothelial growth factor (VEGF) protein expression and lymph node (LN) metastasis in papillary thyroid carcinoma (PTC) among Asians. A range of electronic databases were searched, including Web of Science (1945∼2013), the Cochrane Library Database (Issue 12, 2013), MEDLINE (1966∼2013), EMBASE (1980∼2013), CINAHL (1982∼2013), and Chinese Biomedical Database (CBM) (1982~2013) with cross-referencing without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratio (OR) with their 95 % confidence interval (95 %CI) was calculated. Twelve clinical cohort studies with a total of 1,045 PTC patients were included in our meta-analysis, The results of our meta-analysis revealed that patients with VEGF-positive tumors had a 3.02-fold higher risk of LN metastasis than that of patients with VEGF-negative tumors (OR=3.02, 95 %CI=2.05~4.43, P<0.001). Furthermore, subgroup analysis by country suggested that VEGF-positive expression was associated with an increased risk of LN metastasis in PTC patients among Chinese populations (OR=3.33, 95 %CI=2.30~4.83, P<0.001), but not among Korean, Turkish, and Japanese populations (all P>0.05). Our findings support the view that VEGF protein expression may be correlated with LN metastasis in PTC patients, especially among Chinese populations.

Pancreatic metastasis of papillary thyroid carcinoma: a case report with review of the literature

In this article we give a case report on a PTC patient with pancreatic metastasis. In this case, the patient was admitted to our hospital for recurrence of PTC and occupying pancreatic lesions. We considered that the pancreatic neoplasm may be pancreatic metastasis of PTC but there is no previous experience about therapeutic approaches to this type of metastases. After some discussion the distant metastasis within the pancreas was successfully removed by a laparotomy and postoperative histology confirmed the diagnosis. After that surgery, the patient recovered well and then received total thyroidectomy and cervical lymph node dissection for recurrent thyroid cancer. After recovery he was discharged from hospital without further treatment. Eventually, he died of acute myocardial infarction in January 2010. To conclude, it is widely believed that the surgical operation should be chosen more positively in the management of those patients without multiple organ metastases. Thus on one hand it can serve to make a definite diagnosis, and on the other hand it can help the body get rid of the bulk of the tumor burden to prolong survival time of the patients.

Mapping local orientation of aligned fibrous scatterers for cancerous tissues using backscattering Mueller matrix imaging

Polarization measurements are sensitive to the microstructure of tissues and can be used to detect pathological changes. Many tissues contain anisotropic fibrous structures. We obtain the local orientation of aligned fibrous scatterers using different groups of the backscattering Mueller matrix elements. Experiments on concentrically well-aligned silk fibers and unstained human papillary thyroid carcinoma tissues show that the m22 , m33 , m23 , and m32 elements have better contrast but higher degeneracy for the extraction of orientation angles. The m12 and m13 elements show lower contrast, but allow us to determine the orientation angle for the fibrous scatterers along all directions. Moreover, Monte Carlo simulations based on the sphere-cylinder scattering model indicate that the oblique incidence of the illumination beam introduces some errors in the orientation angles obtained by both methods. Mapping the local orientation of anisotropic tissues may not only provide information on pathological changes, but can also give new leads to reduce the orientation dependence of polarization measurements.

Delayed luminescence to monitor programmed cell death induced by berberine on thyroid cancer cells

Correlation between apoptosis and UVA-induced ultraweak photon emission delayed luminescence (DL) from tumor thyroid cell lines was investigated. In particular, the effects of berberine, an alkaloid that has been reported to have anticancer activities, on two cancer cell lines were studied. The FTC-133 and 8305C cell lines, as representative of follicular and anaplastic thyroid human cancer, respectively, were chosen. The results show that berberine is able to arrest cell cycle and activate apoptotic pathway as shown in both cell lines by deoxyribonucleic acid fragmentation, caspase-3 cleavage, p53 and p27 protein overexpression. In parallel, changes in DL spectral components after berberine treatment support the hypothesis that DL from human cells originates mainly from mitochondria, since berberine acts especially at the mitochondrial level. The decrease of DL blue component for both cell lines could be related to the decrease of intra-mitochondrial nicotinamide adenine dinucleotide and may be a hallmark of induced apoptosis. In contrast, the response in the red spectral range is different for the two cell lines and may be ascribed to a different iron homeostasis.

BRAF(V600E) mutation is not a positive predictor for distant metastasis in sporadic papillary thyroid carcinoma

BACKGROUND

BRAF(V600E) mutation is correlated with local aggressive clinicopathological features in papillary thyroid carcinoma; yet the relationship between this genetic variation and distant papillary thyroid carcinoma metastasis was unclear. This study aimed to investigate whether BRAF(V600E) is predictive for distant metastasis in the Chinese population.

METHODS

One hundred and seven patients with papillary thyroid carcinoma were enrolled in this study, including 43 patients with distant metastasis and 64 patients without. Quantitative real-time polymerase chain reaction was used to detect BRAF(V600E) mutation, while immunohistochemistry was performed to detect vascular endothelial growth factor (VEGF) expression. The associations between distant metastasis and BRAF(V600E) mutation, and VEGF expression as well as local clinicopathological factors were determined.

RESULTS

A total of 28.6% of the patients in the distant metastasis group harbored BRAF(V600E) mutation, which was significantly lower than in the without distant metastasis group (68.8%, P < 0.001). BRAF(V600E) mutation was negatively correlated with positive VEGF expression (P = 0.001). Furthermore, 52.2% of the patients with distant metastasis exhibited VEGF expression, compared with 25.0% of those without. Higher levels of VEGF expression were also observed in the distant metastasis group. Tumor size, extra-thyroid invasion, and BRAF(V600E) mutation were independent predictors for distant metastasis according to multivariate analysis (odds ratios were 2.8, 12.4, and 0.3; 95% CI 1.483-5.334, and 2.950-52.407, 0.100-0.890; P = 0.002, 0.001, and 0.030, respectively). BRAF(V600E) mutation was negatively correlated with distant metastasis in adult subgroup analysis (P = 0.005) but was not an independent parameter.

CONCLUSIONS

BRAF(V600E) mutation is predictive for distant metastasis in papillary thyroid carcinoma but not positively. VEGF may be involved in the pathogenesis of distant metastasis.

Treatment with metformin is associated with higher remission rate in diabetic patients with thyroid cancer

CONTEXT

Clinical trials demonstrated that metformin increases the efficiency of systemic therapy in cancer patients.

OBJECTIVE

We examined whether the efficacy of conventional treatment of differentiated thyroid cancer (DTC) is affected by therapy with metformin in diabetic patients.

DESIGN

We compared the rate of complete response (CR) between diabetics who were treated with metformin (group MF+; n = 34) or not treated (group MF-; n = 21) and control nondiabetic patients (group C; n = 185). We also examined the effects of metformin on DTC cells in vitro.

RESULTS

The groups were comparable in terms of age, sex, body mass index, diabetes management, frequencies of multifocal tumor growth, extrathyroidal extension, and locoregional and distant metastases. Tumor size was significantly smaller in the MF+ group compared with the MF- and C groups (1.37 ± 0.97 vs 2.44 ± 1.49 vs 2.39 ± 1.73 cm, respectively; P = .026). A multivariate model revealed that extrathyroidal extension (P = .018), distant metastases (P < .0001), and lack of treatment with metformin of diabetics (P < .0001) decreased the likelihood of CR. A Cox hazards model revealed that age (P = .025), locoregional metastases (P = .022), distant metastases (P = .003), and lack of treatment with metformin of patients with diabetes (P = .014) are associated with increased risk for shortened progression-free survival. In vitro data revealed that metformin inhibited cancer cell growth, activated cAMP-inducible protein kinase (5'-AMP-activated protein kinase [AMPK]), and down-regulated p70S6K/pS6. Metformin potentiated H₂O₂-inducible activation of AMPK but attenuated pERK and p70S6K. Tumors from MF+ patients demonstrated a lower level of phospho-p70S6K compared with the MF- group.

CONCLUSIONS

Tumor size is smaller in patients treated with metformin, suggesting inhibition of tumor growth by the drug. Among diabetics, the absence of metformin therapy is an independent factor for decreased likelihood of CR and increased risk of shorter progression-free survival. In vitro data suggest that p70S6K/pS6 is likely a molecular target of metformin in DTC cells.

Pulmonary metastasis of a papillary thyroid carcinoma and primary lung adenocarcinoma: two coincident carcinomas at the same location

Tumor-to-tumor metastasis is a fairly rare phenomenon. The lung cancers are the most common donors, but are exceedingly rare as recipients. Here we report a case of a lung adenocarcinoma acting as the recipient of papillary thyroid carcinoma, with multiple spreading foci of the two cancers in the lung simultaneously. The morphology and immunohistochemistry (Napsin-A, Thyroglobulin) are very important in differential diagnosis of lung primary adenocarcinoma and metastatic papillary thyroid carcinoma.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2069496615891134.

Thyroid synovial sarcoma: a case report

Sarcomas are rare tumors account for about 1% of cancers in adult. Soft tissue sarcomas are the most common one. Synovial sarcoma's incident is about 10% of all sarcomas and most commonly rise from para-articular regions in young adults. Based on our knowledge there have been only two reports of thyroid synovial sarcoma in medical literature. We report a 44-year old woman presented with a rapid growing neck mass. The pathology report revealed sarcoma and the immunohistochemistry (IHC) was compatible with synovial sarcoma. It could be understood that synovial sarcoma can be found in various tissues even if there is no synovial cells.

Spindle epithelial tumor with thymus-like differentiation: a case report and review of literature

Spindle epithelial tumor with thymus-like differentiation (SETTLE) is an extremely rare type of thyroid tumor with fewer than 35 reported cases available in the literature so far, most of them having been diagnosed histologically after resection. The tumor is believed to be derived from branchial-pouch or thymic remnants, occurring in young adults, predominantly in males, with a male:female ratio 1.8:1.

CASE

A 14-year-old girl presented with a nodular mass in her right thyroid that had been present for 1 year. Ultrasonological study revealed a heterogeneous solid mass (2.5 × 1.5 × 1.5 cm) in the right lobe of the thyroid. Fine-needle aspiration (FNA) smears were highly cellular and comprised of predominantly dissociated uniform spindle cells with naked oval nuclei along with some aggregates and groups. Occasional islands of epithelial cells were also present. Cytologically, the spindle cells had bland nuclear chromatin, with very scanty mitotic figures. Upon examination of the FNA smears, a provisional diagnosis of SETTLE was suggested along with a request for an incisional biopsy to rule out another differential diagnosis of medullary carcinoma thyroid. On the resected tissue specimen, diagnosis was histologically confirmed to be SETTLE. Immunohistochemical study revealed a strong and diffuse positivity for high-molecular-weight keratin and vimentin, and negativity for thyroglobulin, calcitonin, S-100 protein, desmin, chromogranin and synaptophysin.

CONCLUSION

Cytologically, SETTLE can safely be considered, especially if spindle elements are observed along with the occasional group of epithelial cells in FNA smears from the thyroid of young adults. It can help in the preoperative recognition of lesions based on distinctive cytomorphological features and immunohistochemical characteristics, allowing a more sound therapeutic approach because these patients can present with delayed metastasis.

Cribriform morular variant of papillary thyroid carcinoma: clinical and cytomorphological features on fine-needle aspiration

BACKGROUND

Cribriform-morular variant of papillary thyroid carcinoma (CMV-PTC) is a rare tumor that may arise in patients with familial adenomatous polyposis (FAP), although sporadic instances of this tumor have been reported. When it arises in FAP, CMV-PTC may present before colonic manifestations are apparent, so proper identification and classification are essential for prompt assessment of the colonic disease status and genetic and familial counseling.

METHODS

Nine cases of PTC with cribriform morular cytomorphology were identified at 2 large tertiary-care hospitals; 6 were true CMV-PTC with positive β-catenin and 3 were CMV-like PTC with negative β-catenin. A review of the cytomorphology and a cytology-histology correlation were performed.

RESULTS

Only 1 patient presented with a known history of FAP. Patients presented with a median age of 41 years (range 19-64 years). There was a clear female predilection; 8 of 9 patients (89%) were female. All cases demonstrated the classical nuclear and architectural features of PTC. In addition, the most salient features were large tissue fragments with cribriform architecture and dense cellular morules. The elongated cellular shape of the tumor cells led to the misclassification of one tumor as a tall-cell variant of PTC on the FNA material.

CONCLUSION

CMV-PTC or CMV-like PTC demonstrate cytomorphological features that overlap with classic PTC. β-Catenin immunostaining plays an important role in making a definitive diagnosis.

Malignant pleural effusion resulting from metastasis of thyroid primaries: a cytomorphological analysis

BACKGROUND

Malignant serous cavity effusion caused by primary thyroid cancer is extremely rare in routine clinical practice. Therefore, it is often not included in the differential diagnostic workup of patients presenting with positive effusion cytology.

METHODS

The clinical features were reviewed for 6 patients seen at our institution over the last 26 years for malignant effusion resulting from metastatic thyroid cancer. The cytomorphology from 4 of these cases was also reviewed.

RESULTS

All of the patients found in this study presented with malignant pleural effusion - other serous cavity effusions resulting from metastatic thyroid carcinoma were not seen. These comprised 0.25% of all patients with a known history of thyroid carcinoma and 0.67% of all malignant pleural effusions. One patient had a history of bone metastases, but all the others had no pathological evidence of distant metastatic disease prior to the pleural effusion.

CONCLUSIONS

Malignant pleural effusion rarely results from a thyroid carcinoma after some latency. The diagnosis requires immunohistochemical staining as well as the pertinent clinical context.

Absence of galectin-3 immunostaining in fine-needle aspiration cytology specimens from papillary thyroid carcinoma is associated with favorable pathological indices

BACKGROUND

Galectin-3 (G3) immunostaining of fine-needle aspiration (FNA) samples from thyroid nodules is very useful for the diagnosis of malignancy. The objective of the present study was to determine whether the absence of G3 immunostaining in preoperative FNA samples is associated with favorable clinicopathological parameters, including lymph node (LN) metastasis, in papillary thyroid carcinoma (PTC).

METHODS

The records of 868 patients with PTC who had prethyroidectomy ultrasonography-guided FNA with G3 immunostaining between January 2006 and December 2009 were retrospectively reviewed. G3 immunostaining was considered positive if the percentage of tumor cells showing definite cytoplasmic immunostaining exceeded 5%. Patients who had negative G3 immunostaining of FNA samples were assigned to the G3-negative (G3N) group; whereas those who had positive G3 immunostaining were assigned to the G3-positive (G3P) group.

RESULTS

There were 92 patients who were assigned to the G3N group (10.6%) because of the negative staining for G3 in the preoperative FNA samples from their thyroid nodules. The proportion of PTC subtypes in the G3N and G3P groups was similar (p=0.376). There was less frequent thyroid capsular invasion (46.7% vs. 66.5%, p<0.001), extrathyroidal extension (28.3% vs. 48.5%, p<0.001), and LN metastasis (22.2% vs. 48.7%, p<0.001) in the G3N group than the G3P group. In multivariate regression analysis, G3N expression predicted a lower risk of LN metastasis (odds ratio=0.37, 95% confidence interval 0.18-0.78) after adjustment for other clinicopathological parameters. Over a median follow-up of 33 months, no association was observed between G3N and disease-free survival.

CONCLUSION

The absence of G3 expression in FNA samples from PTC is associated with pathological parameters considered less aggressive than is the case for PTCs with G3 expression, including being a negative predictor of negative LN involvement. Long-term follow-up studies, however, are needed to verify whether G3N patients have lower recurrence and mortality rates.

Diagnostic utility of thyroglobulin measurement in the fine needle aspirates from cervical lymph nodes: a case report

Fine needle aspiration cytology (FNAC) is the more accurate diagnostic method for cervical lymph node (CLN) metastasis from differentiated thyroid cancers (DTC). However, FNAC diagnosis of cystic CLN is, in most cases, uninformative due to inadequate cellularity. Recently, thyroglobulin (Tg) detection in FNAC needle washout fluid has been shown to improve the diagnostic accuracy of FNAC, and its routine association with cytology is recommended. We here describe the case of a 20 yr old girl complaining of the recent appearance of palpable non-painful laterocervical nodes in the neck. Ultrasound examination revealed the presence of 3 cystic CLNs and 2 mixed thyroid nodules, with the larger one showing irregular margins. On the latter, and on 2 larger CLNs, FNAC was performed, and both Tg protein and mRNA were determined in the needle washout. The cytological analysis was not diagnostic for the two CLNs, while that of the thyroid nodule reported the presence of colloid and groups of thyrocytes with normal morphology. Both CLNs showed, however, high levels of Tg protein and were positive for Tg mRNA, suggestive of metastatic DTC. Based on these findings, the FNAC analysis was performed on the second smaller thyroid nodule suggesting (Tir4) the presence of PTC. The patient was then subjected to total thyroidectomy with lymph nodes resection of the central and homolateral compartments. The histological diagnosis confirmed the presence of a PTC in the small nodule and metastatic lymph nodes. In conclusion, this case confirms that the cytological diagnosis of cystic lymph nodes is challenging, and that the measurement of Tg protein and/or mRNA in the needle washout may overcome this limitation.

Loss of expression of the oncosuppressor PTEN in thyroid incidentalomas associates with GLUT1 plasmamembrane expression

AIM

Molecular imaging diagnosis with FDG-PET ((18)F-fluorodeoxyglucose positron emission tomography with computed tomography) can reveal the presence of un-suspected thyroid cancer that are referred to as "incidentaloma" because of the incidental finding. The glucose analogue (18)FDG is internalized in the cells by glucose transporters belonging to the GLUTs family. The surface expression of GLUT is under the control of the PI3k/Akt pathway. PTEN is an oncosuppressor frequently mutated or deleted in thyroid cancers. The lipid phosphatase activity of wild type PTEN switches off the Akt pathway. Here we tested the hypothesis that PTEN expression might affect the surface expression of GLUT1 and therefore influence the possibility of "incidental" detection of thyroid cancer based on FDG-PET.

METHODS

The biopsy of 8 patients, who were incidentally diagnosed with PTC by (18)F-fluorodeoxyglucose positron emission tomography with computed tomography, was assayed by immunofluorescence for the co-expression of the PTEN oncosuppressor and of GLUT1.

RESULTS

Loss of PTEN expression was detected in the majority of investigated cases (N.=6/8). Strikingly, while the two PTEN positive cases were negative for GLUT1 expression, the PTEN negative cases showed intense expression of GLUT1 at the cell surface.

CONCLUSION

The present observations, though made in a limited number of cases, suggest that PTEN negative thyroid cancers have high chances to be revealed as incidentalomas at FDG-PET.

Clinical, genetic, and immunohistochemical characterization of 70 Ukrainian adult cases with post-Chornobyl papillary thyroid carcinoma

BACKGROUND

Increased incidence of papillary thyroid carcinoma (PTC) is observed as a consequence of radiation exposure in connection to the Chornobyl nuclear plant accident in 1986. In this study, we report a cohort of adult Ukrainian patients diagnosed with PTC from 2004 to 2008 following exposure at the age of 18 years or younger.

METHODS

In total, 70 patients were identified and clinically characterized. The common BRAF 1799T>A mutation was assessed by pyrosequencing, the RET/PTC1 and RET/PTC3 (NCOA4) rearrangements by RT-PCR, and the expression of Ki-67 (MIB-1 index), BCL2, cyclin A, and cyclin D1 by immunohistochemistry.

RESULTS

In total, 46/70 (66%) cases carried a BRAF mutation and/or a RET/PTC rearrangement. A BRAF mutation was detected in 26 tumors, RET/PTC1 in 20 cases, and RET/PTC3 in four cases. In four of these cases, BRAF mutation and RET/PTC rearrangement were coexisting. The BRAF mutation was underrepresented among PTCs with accompanying chronic lymphocytic thyroiditis (CLT) compared with PTCs without this feature (12 vs 44%). MIB-1 proliferation index determined by double staining with leukocyte common antigen was low (mean 0.8%; range 0.05-4.5%). Moreover, increased expression of cyclin A was observed in PTCs with a tumor size >2 cm compared with PTCs ≤2 cm (1.2 vs 0.6%). BCL2 and cyclin D1 showed frequent expression but without associations to clinical characteristics or amplification of the CCND1 locus.

CONCLUSIONS

Our results suggest that this cohort has frequent BRAF mutation, RET/PTC1 rearrangement, and low proliferation index. Furthermore, BRAF 1799T>A was underrepresented in PTCs with CLT, and cyclin A expression was associated with increased PTC tumor size.

Morphoproteomic confirmation of an activated nuclear factor-кBp65 pathway in follicular thyroid carcinoma

The role of nuclear factor (NF)-кBp65 pathway in the pathogenesis of follicular thyroid carcinoma (FTC) has not been fully investigated. We retrieved 10 cases of FTC from our file. Tissue microarrays (TMAs) were constructed using 2.0 mm cores from formalin-fixed, paraffin-embedded tissue blocks. TMA sections were immunohistochemically stained for phosphorylated (p)-NF-кBp65 (Ser 536), cyclooxygenase-2 (COX-2), IL-8, and glutathione S-transferase (GST)-pi. Staining intensity (0-3+), extensiveness (0-100%) and subcellular compartmentalization were evaluated. Both nuclear and cytoplasmic immunoreactivities with p-NF-кBp65 (Ser 536) antibodies were observed in all 10 cases, including moderate to strong nuclear staining intensity with a range of extensiveness in 20% - 100% of tumor cells. Moderate (2+) or strong (3+) cytoplasmic expressions of COX-2 and IL-8 were present in 60-100% and 50- 100% of tumor cells, respectively, in all cases. GST-pi was diffusely (70-100%) and moderately or strongly staining the tumor cytoplasm in all cases (except one case with insufficient tissue) with three of them demonstrating nuclear positivity as well. Morphoproteomic analysis reveals the constitutive activation of the NF-кBp65 pathway in follicular thyroid carcinomas as evidenced by phosphorylation at Ser 536 with nuclear translocation and with correlative expression of transcriptionally activated gene products (COX-2, IL-8, and GST-pi). This observation may provide a molecular basis for the tumor biology and targeted therapies for follicular thyroid carcinoma.

Foxp3 expression is associated with aggressiveness in differentiated thyroid carcinomas

OBJECTIVES

Forkhead box P3 (FoxP3) expression has been observed in human cancer cells but has not yet been reported in thyroid cells. We investigated the prognostic significance of both FoxP3 expression and intratumoral FoxP3(+) lymphocyte infiltration in differentiated thyroid carcinoma cells.

METHODS

We constructed a tissue microarray with 385 thyroid tissues, including 266 malignant tissues (from 253 papillary thyroid carcinomas and 13 follicular carcinomas), 114 benign lesions, and 5 normal thyroid tissues.

RESULTS

We determined the expression of FoxP3 in both tumor cells and tumor-infiltrating lymphocytes using immunohistochemical techniques. Cellular expression of FoxP3 was evident in 71% of benign and 91.9% of malignant tissues. The nuclear and cytoplasmic expression patterns were quantified separately. A multivariate logistic regression analysis indicated that cytoplasmic FoxP3 expression is an independent risk factor for thyroid malignancy. Cytoplasmic FoxP3 staining was inversely correlated with patient age. Nuclear FoxP3 staining was more intense in younger patients and in tumors presenting with metastasis at diagnosis. FoxP3(+) lymphocytes were more frequent in tumors smaller than 2 cm, those without extrathyroidal invasion, and in patients with concurrent chronic lymphocytic thyroiditis.

CONCLUSIONS

We demonstrated FoxP3 expression in differentiated thyroid carcinoma cells and found evidence that this expression may exert an important influence on several features of tumor aggressiveness.

Delta-like 4/Notch pathway is differentially regulated in benign and malignant thyroid tissues

BACKGROUND

Angiogenesis plays an essential role in embryonic and tumoral developments. Vascular endothelial growth factor (VEGF), one of the best known proangiogenic factors, is increased in thyroid cancers, especially in papillary carcinomas (PC). However, other regulating mechanisms refine VEGF-induced cellular changes, such as the Notch family of ligands and receptors. Their role has not yet been investigated in the thyroid. The purpose of our study was to analyze the expression of Notch1, Notch4, and Delta-like 4 (DLL4) in benign and malignant thyroid lesions.

METHODS

The expression of Notch1, Notch4, and DLL4 was analyzed by immunohistochemistry, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), and Western-blot in normal thyroids (NTs), hyperplasic thyroids from patients with Graves' disease (GD), microcarcinomas, PC, and follicular carcinomas.

RESULTS

The immunohistochemical expression of Notch1, Notch4, and DLL4 was highly variable in thyrocytes from NTs and GD. In contrast, the staining in tumors was homogeneous and often intense. The increased expression of Notch1, Notch4, and DLL4 in carcinomas compared with the neighboring normal tissue was confirmed by qRT-PCR and Western-blot. However, only capillary endothelial cells from GD samples were positive for DLL4, the expression being restricted to large vessels in carcinomas and NTs.

CONCLUSIONS

The detection of Notch1, Notch4, and DLL4 in thyrocytes and their regulation in various pathologies suggest that this pathway may play a role in thyroid carcinogenesis and angiogenesis.

Thyroid disorders in pregnancy

Maternal hypothyroidism, thyroid antibody positivity, and hyperthyroidism may pose significant risks in terms of pregnancy complications and fetal adverse effects. Treatment of hyperthyroidism with thionamides remains the standard of care during pregnancy. Radioiodine use is contraindicated in pregnancy, including in the treatment of thyroid carcinoma, because of the risk of fetal hypothyroidism, subsequent cognitive impairment, and even fetal death. Normal thyroid function during pregnancy is essential to ensure delivery, to the best extent possible, of a healthy baby, which may be achieved with frequent monitoring of thyroid function during gestation and cautious adjustment of medications during treatment.

Micropapillary thyroid carcinoma and concomitant ectopic thyroid tissue in the adrenal gland: metastasis or metaplasia?

BACKGROUND

Ectopic thyroid tissue is a rare finding but has been reported in many thoracic and abdominal locations. It is usually an incidental pathologic finding after an unrelated surgical intervention. When thyroid tissue is found outside the thyroid bed, it is important to rule out thyroid cancer metastasis.

PATIENT FINDINGS

We present a case of a 61-year-old African American woman who was incidentally found to have concomitant ectopic thyroid tissue in the adrenal gland and a papillary thyroid microcarcinoma (PTMC) in the right lobe of the thyroid.

SUMMARY

The concurrent finding of ectopic thyroid tissue and PTMC posed the diagnostic dilemma of whether the extrathyroidal tissue was metastasis or metaplasia, with very different treatment implications. Although many of these incidental micropapillary cancers are indolent, some patients do experience local or distant metastasis. Therefore, it is important to delineate which of these microtumors are likely to metastasize. Some tumor markers and gene mutations have been proposed to help differentiate the more benign tumors from the more aggressive tumors, but there is currently no standard method for determination of metastatic potential.

CONCLUSIONS

Here we present the seventh known case of ectopic thyroid tissue in the adrenal gland and the first case of concomitant incidental PTMC in the setting of this ectopic tissue finding. Using this case, we discuss the diagnostic and therapeutic challenges faced and propose the use of biomarkers to help determine the metastatic potential of these tumors.

Upregulation of the signal transducers and activators of transcription 3 (STAT3) pathway in lymphatic metastases of papillary thyroid cancer

Papillary thyroid cancer (PTC) has an impressive propensity for lymphatic spread. Signal transducers and activators of transcription 3 (STAT3), constitutively activated in many different cancers, may play a role in PTC lymphatic metastases. We examined 49 patients with PTC, 22 with and 27 without lymphatic metastases. All patients had a total thyroidectomy with lymph node dissection to document true node negative cases. The level of STAT3 expression in benign, non-neoplastic thyroid tissue is barely detectable by immunohistochemistry. Only 11 of the 35 (31%) specimens exhibited weak immunostainingfor STAT3 and pSTAT3 was found weakly positive in 3 of 35 (9%) benign specimens. Expression of STAT3 in all PTC primary tumors was 98% (40/41) and thus significantly higher than corresponding benign thyroid tissue (p=0.0001). pSTAT3 was found in 37% of primary tumors (15/41) and this was significantly higher than pSTAT3 expression in benign tissue (p=0.006). Comparing node-positive and node-negative primary tumors, there was no difference in staining intensity for STAT3 where strong (2+) staining was seen 12/19 node-positive tumors and 13/22 node-negative tumors (p=1). Regarding pSTAT3 expression in primary PTC tumors, node negative cases (n=22) exhibited significantly less staining compared to node positive cases (n=19). Only 4 of 22 (18%) cases in the node-negative group were weakly (1+) positive for pSTAT3 while 12 of 19 (58%) cases in the node-positive group were positive (p=0.011) with 45% of these specimens exhibiting strong (2+) staining. Lymphatic metastases were highly positive (>93%) for both STAT3 and pSTAT3. The STAT3 pathway is ubiquitous in PTC and activated pSTAT3 is significantly upregulated in PTC tumors with metastatic disease. This study is the first to suggest a potential role for activated pSTAT3 in lymphatic metastases in thyroid cancer.

Secretome-based identification and characterization of potential biomarkers in thyroid cancer

In search of thyroid cancer biomarkers, proteins secreted by thyroid cancer cell lines, papillary-derived TPC-1 and anaplastic-derived CAL62, were analyzed using liquid chromatography-tandem mass spectrometry. Of 46 high-confidence identifications, 6 proteins were considered for verification in thyroid cancer patients' tissue and blood. The localization of two proteins, nucleolin and prothymosin-α (PTMA), was confirmed in TPC-1 and CAL62 cells by confocal microscopy and immunohistochemically in xenografts of TPC-1 cells in NOD/SCID/γ mice and human thyroid cancers (48 tissues). Increased nuclear and cytoplasmic expression of PTMA was observed in anaplastic compared to papillary and poorly differentiated carcinomas. Nuclear expression of nucleolin was observed in all subtypes of thyroid carcinomas, along with faint cytoplasmic expression in anaplastic cancers. Importantly, PTMA, nucleolin, clusterin, cysteine-rich angiogenic inducer 61, enolase 1, and biotinidase were detected in thyroid cancer patients' sera, warranting future analysis to confirm their potential as blood-based thyroid cancer markers. In conclusion, we demonstrated the potential of secretome analysis of thyroid cancer cell lines to identify novel proteins that can be independently verified in cell lines, xenografts, tumor tissues, and blood samples of thyroid cancer patients. These observations support their potential utility as minimally invasive biomarkers for thyroid carcinomas and their application in management of these diseases upon future validation.

Hyalinizing trabecular tumor and papillary carcinoma of the thyroid

BACKGROUND

Hyalinizing trabecular tumor (HTT) is a rare thyroid neoplasm, which shares some histologic features with thyroid papillary carcinoma (TPC). Clinically, it is frequently misdiagnosed as papillary carcinoma, even for some experienced pathologists. The aim of this study was to investigate whether HTT is variant of TPC or HTT is an independent entity of thyroid neoplasm.

METHODS

The expression of CK19, galectin-3, HBME-1 and MIB-1 was detected by immunohistochemical staining in 12 cases of hyalinizing trabecular tumor and 20 cases of thyroid papillary carcinoma.

RESULTS

Two of the 12 HTT samples were positive or focally positive for CK19. Four of the 12 samples of HTT presented positive to galectin-3; 3 were stained strongly and the other one was focally positive. None of the 12 samples of HTT was positive for HBME-1. Five in 12 HTT samples were stained in nucleus for MIB-1. Almost all the 20 cases of thyroid papillary carcinoma were intensely stained for CK19, galectin-3 and HBME-1. Fifteen in 20 cases of thyroid papillary carcinoma showed nuclear staining for MIB-1.

CONCLUSIONS

HTT is an independent thyroid neoplasm, not a variant of TPC. This study could help in the differential diagnosis of HTT from TPC. CK19, galectin-3 and HBME-1 are adequate to identify HTT and TPC, but MIB-1 does not play an important role in discrimination between HTT and TPC.

Thyroglobulin antibody is associated with increased cancer risk in thyroid nodules

BACKGROUND

The association between autoimmune thyroiditis (AIT) and thyroid cancer is still not clear despite many previous reports. This study investigated whether serologic thyroid antibodies are predictive of thyroid cancer in patients with thyroid nodules.

METHOD

We retrospectively reviewed records of patients with thyroid nodules evaluated by ultrasonography-guided fine-needle aspiration cytology at our institution between January 2006 and December 2008. Thyroid autoimmunity was assessed by measuring thyroglobulin antibody (TgAb) and thyroid peroxidase antibody (TPOAb). The final outcome deciding a benign or malignant status involved a combination of cytology and histology.

RESULTS

Of the 1638 patients, malignant nodules had a higher rate of positive TgAb (30.8% vs. 19.6%; p < 0.001) and elevated thyrotropin (TSH) levels (2.5 +/- 2.8 mIU/L vs. 2.1 +/- 2.0 mIU/L; p = 0.021) than benign nodules. The rate of positive TPOAb was not higher in malignant nodules, although both TPOAb and TgAb were well correlated with TSH levels and histological AIT. In the multivariate analysis, a positive TgAb was significantly associated with thyroid cancer (odds ratio [OR] = 1.61, 95% confidence interval [CI] 1.12-2.33) with upper tertile of normal range of TSH levels (OR = 1.72, 95% CI 1.12-2.63) and above normal range of TSH levels (OR = 1.98, 95% CI 1.06-3.70).

CONCLUSION

We report for the first time that a positive serum TgAb test was an independent predictor for thyroid malignancy in thyroid nodules along with serum TSH levels regardless of the presence of AIT. Our results suggest that TgAb measurement could give additional information for predicting malignancy in cytologically indeterminate thyroid nodules in conjunction with clinical risk factors and TSH levels.

Detection of BRAF mutation on fine needle aspiration biopsy specimens: diagnostic and clinical implications for papillary thyroid cancer

OBJECTIVE

To detect the BRAF mutation on fine needle aspiration biopsy (FNAB) specimens in papillary thyroid cancer (PTC).

STUDY DESIGN

Eight fresh FNAB specimens and 10 patients' FNAB slides with cytologic examination were examined for the presence of BRAF V600E mutation by direct DNA sequencing.

RESULTS

Genomic DNA was all successfully extracted from both fresh FNAB specimens and patients' FNAB slides. Moreover, BRAF V600E mutation was detected in 2 of 8 fresh FNAB specimens and 6 of 10 patients' FNAB slides.

CONCLUSION

We demonstrated for the first time that it is feasible to detect a BRAF mutation from a small number of fresh FNAB specimens or slides in China, suggesting that detection of BRAF mutation on FNAB samples is useful not only for preoperative diagnosis of PTC but also for accurate pathologic diagnosis and prognosis.

Selenoenzymes, laboratory parameters, and trace elements in different types of thyroid tumor

This study was performed to investigate selenoenzyme activities and trace element concentrations in thyroid tissues, with reference to other parameters routinely used to characterize thyroid function. This was to reveal relevant parameters as possible additional markers of tumor grade, clinical course, and prognosis of thyroid disorders. The tissue samples were obtained during surgical treatment (total or near total thyroidectomy) of 122 patients with different types of thyroid tumor. For most of the investigated parameters in different groups of patients, we did not find statistically significant differences. In the majority of cases, thyroid benign or malignant tumors were not accompanied by significant derangement of the gland selenoenzymes and of either intrathyroidal or plasma concentration of selenium. Nevertheless, types I and II iodothyronine deiodinases were the most promising (among selenoenzymes) targets for diagnoses and possibly therapy of thyroid tumors. Higher activities of both enzymes in cases with Graves' disease, as compared with other thyroid lesions, suggest their involvement in the pathogenesis of this condition. Patients with struna nodosa had higher levels of thyroid Zn, Cu, and Pb as compared with papillary carcinoma subjects and also a higher level of Cu than follicular carcinoma cases. The above diagnostics may play a similar role to some of the general thyroid function indices, TSH, anti-TG, anti-TPO, and calcitonin, which can partially distinguish between various thyroid tumors. In conclusion, some of selenium status markers, when accompanied with general parameters, and trace elements can serve as factors with pathophysiologic relevance and be helpful in the identification of malignant disease. Multivariate statistical methods should be employed to tackle a broad array of thyroid tumor diagnostic data in a short time. Partial least squares model and other pattern recognition methods seem to be the most appropriate methods for that task. The miniaturization of all the steps of complex analytical procedure should be developed in a way to allow its completion as sensitive, robust, and efficient for use of the small quantity of material provided by fine-needle biopsy.

[Surface detection of thyroid cancer by Fourier transform infrared spectroscopy]

OBJECTIVE

To explore a novel non-invasive method in detection of thyroid cancer by Fourier transform infrared (FTIR) spectroscopy.

METHODS

Surface FTIR spectra of 15 cases of thyroid cancer and 51 cases of normal subjects were collected. 22 variables of 11 bands including peak positions and relative intensities were measured and all data were statistically analyzed.

RESULTS

In the cancer group: (1) the peak position of 1743 cm(-1) was shifted toward higher wave number (P < 0.05), and that of 1250 cm(-1) to the lower (P < 0.05), when compared to those of normal ones. (2) The relative intensity ratios of I(1546)/I(1460), I(1250)/I(1460), I(1120)/I(1460), I(1080)/I(1460) were significantly increased (P < 0.05). (3) The presence rate of band of 1340 cm(-1) was significantly decreased (P < 0.05).

CONCLUSION

FTIR surface spectra may become a novel powerful non-invasive approach of detecting thyroid cancer in regular routine check-up.

Perfluorooctane sulfonate and perfluorooctanoic acid in surgical thyroid specimens of patients with thyroid diseases

BACKGROUND

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are ubiquitous compounds that may act as endocrine disruptors, neurotoxic agents, and fetal development perturbing substances and may also be carcinogenic, as recently demonstrated in experimental animal models. There is little information on the potential for these compounds to affect the thyroid. Therefore, this study was performed to measure the intrathyroidal levels of PFOA and PFOS in surgical specimens of thyroid glands and to determine if there was a relationship between the concentrations of these substances and the clinical, biochemical, and histologic phenotype of the patients from whom the thyroids were obtained. We also sought to determine if there was a relationship between tissue and serum levels of both PFOA and PFOS.

METHODS

PFOA and PFOS were measured in 28 patients undergoing thyroid surgery for benign (15 multinodular goiters and 7 Graves' disease) and malignant (5 papillary and 1 follicular carcinoma) thyroid disorders.

RESULTS

PFOA and PFOS were detectable in all surgical specimens of thyroid tissue. Their median concentrations were 2.0 ng/g (range = 0.4-4.6 ng/g) and 5.3 ng/g (range = 2.1-44.7), respectively. Intrathyroidal concentrations of PFOA and PFOS were similar in the thyroids of patients with thyroid diseases as in thyroid glands obtained at autopsy. There was no relationship between the intrathyroidal concentrations of either PFOA or PFOS and the underlying thyroid disease. A significant correlation between the serum and the tissue levels of PFOS was found in all patients. The serum concentrations of PFOA and PFOS were significantly higher than those in the correspondent surgical specimens.

CONCLUSIONS

These observations do not support the view that PFOA and PFOS are actively concentrated in the thyroid. PFOA and PFOS, however, are both found in surgical and autopsy thyroid specimens. Therefore, further studies to determine if they have disrupting effects in thyroid cells or tissue, and studies to compare populations with and without these compounds in their thyroid glands, are important.

Poorly differentiated thyroid carcinoma mimicking adenoid cystic carcinoma on aspiration cytology: a case report

BACKGROUND

Spherical hyaline globules present a characteristic cytologic picture classically seen in salivary gland tumors. This pattern in fine needle aspiration cytology (FNAC) of thyroid malignancies is rare. Sporadic reports of papillary and follicular carcinoma with adenoid cystic pattern are described in the literature.

CASE

We report, to our knowledge, the first documented case of poorly differentiated thyroid carcinoma with adenoid cystic pattern on aspiration cytology. An 80-year-old man presented with a thyroid nodule of 3 years' duration. FNAC smears consisted predominantly of cells arranged around spherical hyaline globules resembling adenoid cystic carcinoma. Histopathologic examination showed a poorly differentiated thyroid carcinoma. Immunohistochemically, the tumor cells showed positive reaction for thyroglobulin and cytokeratin.

CONCLUSION

Poorly differentiated carcinoma of the thyroid presents a variable cytologic picture. Awareness of the cytomorphologic spectrum reduces the possibility of diagnostic error. Reliance on hyaline globules as the sole criterion results in erroneous diagnosis.

Infarction in a thyroid nodule after fine needle aspiration: report of 2 cases with a discussion of the cause of pitfalls in the histopathologic diagnosis of papillary thyroid carcinoma

BACKGROUND

In case of difficulty in the interpretation of fine needle aspiration (FNA) smears of a thyroid nodule, histopathologic examination is advised to arrive at a definitive diagnosis. On rare occasions, a specific diagnosis may be given based on cytologic examination, but FNA is followed by infarction of the thyroid nodule, with resultant difficulty in interpretation or even misinterpretation of bistopathologic material. We report 2 such cases.

CASES

Two cases were diagnosed as papillary thyroid carcinoma (PTC) by FNA cytology, but histopathology reports indicated colloid goiters with infarcted nodules. Review of histopathologic material showed features of PTC in the viable tissue at the periphery of nodules. Immunohistochemical study for galectin-3 and CD44 in 1 of the cases supported the diagnosis of PTC.

CONCLUSION

We suggest that while reporting on an infarcted nodule in paraffin sections of a thyroidectomy specimen, the histopathologist should be careful to look thoroughly at its periphery for the surviving cells and their detailed morphologic features, especially if there is a prior FNA cytology report of a neoplasm.

Galectin-3 cytotest in thyroid follicular neoplasia: a prospective, monoinstitutional study

OBJECTIVE

To analyze the utility of galectin-3 (Gal3) immunohistochemistry (IHC) on preoperatively obtained fine needle aspiration biopsy (FNAB) in identifying the subgroup of follicular neoplasia (FN) patients who were candidates for thyroidectomy.

STUDY DESIGN

This prospective, monoinstitutional study applied a standardized Gal3 immunostaining protocol (cell block specimens; Gal3 scores: G0 [no Gal3+ve IHC reaction], G1 [Gal3+ve thyrocytes < or = 10%], G2 [Gal3+ve thyrocytes > 10%) in 100 consecutive cytologically assessed FN. All patients underwent thyroidectomy, and the FNs were always histologically categorized (World Health Organization criteria).

RESULTS

The overall malignancy rate was 15%. Gal3 expression in presurgical samples significantly correlated with the postoperative diagnosis (p < 0.0001). When all positive Gal3 cases were pooled together (G1+G2), the IHC test performed as follows: sensitivity = 80%; specificity = 86%; positive predictive value = 50%; negative predictive value = 96%. All the Gal3-G2 cases (presurgical cell block) showed postoperative evidence of malignancy. All 9 cases of papillary tumor expressed Gal3 in both cell block and postoperative histology. Among the 6 follicular cancers, the prevalence of Gal3 overexpression in the cell block was 50%.

CONCLUSION

The cell block procedure applied to thyroid FNAB samples enables the Gal3 cytotest to be implemented usefully in the preoperative identification of those cases of FN postoperatively found to be malignant (also significantly reducing the number of inappropriate thyroidectomies). Strong Gal3 expression should prompt immediate surgical treatment.

Proteomics in thyroid tumor research

BACKGROUND

In recent years, "OMICS" technologies have paved novel ways for the broad-scale identification of molecular signatures and signaling pathways specific to tumorigenesis. Related to this are high hopes for the discovery of biomarkers facilitating diagnosis and prognosis of cancer as well as the option for pathway-targeted tumor treatment. Among the different OMICS methods, the potential of proteomics is just beginning to emerge, and according to the current literature, the proteome is to date the most feasible tool to reflect tumor biology.

OBJECTIVE

In this review we discuss the application of proteomics to the field of thyroid tumor research.

CONTEXT

First, we provide an overview of different methods for protein expression profiling and then discuss specific requirements and challenges of thyroid proteomics. Furthermore, we summarize results of published proteomics studies on human thyroid tumors and finally explore perspectives of thyroid proteomics, which, combined with mRNA expression profiling and traditional biochemical methods, is increasingly contributing to an improved understanding of thyroid tumorigenesis and may in the future open novel avenues in thyroid cancer therapy.

Role of basic fibroblast growth factor in the pathogenesis of nodular goiter

Thyroid epithelial cells are known to produce several growth factors and cytokines which influence thyroid cell growth and function in an autocrine and/or paracrine manner. It is already known that insulin-like growth factor I (IGF I) is overexpressed in toxic adenomas whereas epidermal growth factor (EGF) is found predominantly in thyroid neoplasia. We now investigated the expression of bFGF by immunohistochemistry in thyroid tissue of patients with toxic adenoma (n = 27), cold nodules (n = 27) and for comparison in Graves' disease (n = 5). In addition bcl-2-oncoprotein expression in these tissues were also detected by immunohistochemistry. Most of bFGF immunostaining was found in the connective tissue of all thyroid tissues with a predominance in adenomas and in Graves' diseases. The collagen surrounding the thyroid follicles close to their basal membrane were homogeneously and intensively stained. All the cytoplasm of fibroblast in the connective tissue were strongly positive. Within the cytoplasm of only 2-10% thyroid epithelial cells bFGF immunostaining was found without any difference between toxic adenomas or cold nodules. In the tissue of patients with Graves' disease, less than 2% of thyrocytes were stained. All thyroid epithelial cell showed clearly an immunostaining for bcl-2-oncoprotein in nodular goiter as well as Graves' disease.

Tenascin C in medullary thyroid microcarcinoma and C-cell hyperplasia

Tenascin C (Tn-C) is an extracellular matrix glycoprotein that is expressed early in carcinogenesis including intraepithelial neoplastic lesions of different organs. In this study, we analyze whether stroma reaction seen by Tn-C expression is detected early in tumorigenesis of medullary thyroid carcinoma (MTC) including medullary microcarcinoma and C-cell hyperplasia (CCH), which is accepted to be a precursor lesion of MTC in the setting of RET oncogene germ-line mutation. Tn-C was expressed in the stroma of all medullary microcarcinoma and in the stroma next to CCH. Stromal Tn-C expression was significantly more often seen in CCH with concomitant MTC than in isolated CCH of hereditary as well as nonhereditary cases (p = 0.001 and p = 0.016, respectively). We conclude that Tn-C expression and thus early stroma remodeling is seen in medullary microcarcinoma and CCH. Stromal Tn-C expression seems to be an indicator of a further step in carcinogenesis of MTC irrespective of a RET oncogene germ-line mutation.

Encapsulated anaplastic thyroid carcinoma transformed from follicular carcinoma: a case report

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is rare but is one of the most aggressive and lethal human malignancies. Cytologically, ATC has a variable morphologic appearance, including squamoid, giant, spindled and pleomorphic cells. The coexistence of ATC and differentiated or poorly differentiated thyroid carcinoma has been described and usually is diagnosed when the disease is locally advanced.

CASE

We describe a case of surgically resectable, encapsulated, well-circumscribed ATC occurring in association with a better differentiated follicular carcinoma diagnosed by fine needle aspiration in a patient exposed to external ionizing radiation.

CONCLUSION

Encapsulated variants of anaplastic carcinoma can be seen in association with lower grade thyroid carcinoma such as follicular carcinoma. Accurate diagnosis is dependent on adequate sampling.

Identification of a neck lump as a lymph node metastasis from an occult contralateral papillary microcarcinoma of the thyroid: key role of thyroglobulin assay in the fine-needle aspirate

BACKGROUND

Thyroglobulin (Tg) assay of material from fine-needle aspiration of neck masses can help distinguish neck masses of thyroid origin from other masses. We describe its utility in a patient with an unusual constellation of findings, a neck lump identified as a lymph node metastasis from a contralateral occult papillary thyroid carcinoma (PTC).

SUMMARY

A 56-year-old woman was referred to our center for evaluation of a 15-mm right lateral cervical neck mass which was strongly hypoechoic, not homogenous and contained several microcalcifications. There was no family history of thyroid disease, the patient was euthyroid and was not taking medications for thyroid disorders. On physical examination the thyroid was slightly enlarged and was normal on ultrasound except for a 1 x 3 mm hypoechoic nodule in the middle of the left lobe. Ultrasound-guided fine-needle aspiration biopsy (FNAB) of the right lateral cervical mass was performed with the Tg concentration of the FNAB washout liquid being >300 ng/mL and the cytology showing lymphoid elements mixed with polymorphous epithelial cells with atypical nuclei, suggesting lymph node metastasis from a cancer of epithelial origin. A lymph node metastasis from a papillary thyroid microcarcinoma (micro-PTC) was the presumptive diagnosis with the preoperative staging being Tx N1b. The patient underwent total thyroidectomy and bilateral lymph node dissection. At pathology, the right cervical mass was confirmed as lymph node metastasis of a PTC, and a unifocal micro-PTC was found in the middle left lobe. The patient was readmitted for a therapeutic (131)I dose (4810 MBq). At the time of (131)I administration, the whole-body scan showed only minimal thyroid bed uptake and serum Tg was <1 ng/mL. She was maintained on l-thyroxine treatment (150 microg/d). Five year later she did not have evidence of recurrent or residual PTC.

CONCLUSIONS

We describe the first case of contralateral lymph node metastasis from a unifocal micro-PTC identified by the detection of high Tg levels in the wash-out liquid of FNAB.

Thyroid metastases from typical carcinoid of the lung differentiating between medullary thyroid carcinoma and neuroendocrine tumor metastasis to the thyroid

BACKGROUND

Although very rare, carcinoid tumors of the lung may present as thyroid metastatic nodules, thus raising diagnostic difficulties for clinicians, surgeons, and pathologists. The most problematic differential diagnosis is with medullary thyroid carcinoma (MTC), a well-differentiated neuroendocrine tumor showing cytological and histological features similar to those of a lung carcinoid.

SUMMARY

We report a case of thyroid metastases from a typical carcinoid of the lung. The thyroid tumors were diagnosed in a 37-year-old woman known to have a lung nodule radiologically identified 8 years earlier, for which neither cytological nor histological analyses were performed. Fine-needle aspiration cytology of the thyroid nodule suggested a neuroendocrine tumor, possibly a MTC. However, the lack of both elevated calcitonin (CT) blood level and CT immunoreactivity in cytological smears ruled out the diagnosis of MTC in favor of a metastatic neuroendocrine tumor. Octreoscan demonstrated the neuroendocrine nature of the known lung neoplasm and the patient underwent right lung lobectomy together with total thyroidectomy. Histology examination confirmed the diagnosis of thyroid metastases from typical carcinoid of the lung. The patient is alive and free of disease 7 years after surgery.

CONCLUSION

The rarity of this case offered the opportunity to discuss the most important criteria for distinguishing metastatic from primary neuroendocrine tumors of the thyroid and the indolent behavior of metastatic typical carcinoids of the lung.

Loss of Rap1GAP in papillary thyroid cancer

CONTEXT

Rap1 GTPase-activating protein (GAP) regulates the activity of Rap1, a putative oncogene. We previously reported Rap1GAP was highly expressed in normal human thyroid cells and decreased in five papillary thyroid carcinomas (PTCs).

OBJECTIVES

To confirm the significance of these findings, we analyzed Rap1GAP expression in a larger set of benign tumors (adenomas and hyperplastic nodules) and PTCs. We determined whether the presence of the BRAF(V600E) mutation or allelic loss of Rap1GAP related to changes in Rap1GAP protein expression. To determine the consequences of Rap1GAP loss, we targeted Rap1GAP in culture using small interfering RNA.

DESIGN, PATIENTS, AND METHODS

A highly specific Rap1GAP antibody was applied to sections of 55 human thyroid tissues. Genomic DNA was analyzed for the presence of the BRAF(V600E) mutation, and loss of Rap1GAP. Rap1GAP expression in rat thyroid cells was abolished using small interfering RNA.

RESULTS

We observed that down-regulation of Rap1GAP in benign lesions and PTCs was common. Rap1GAP expression was more severely decreased in PTCs. Loss of Rap1GAP expression was observed in multiple histological variants of PTCs. Approximately 20% of PTCs and adenomas exhibited allelic loss of Rap1GAP. Loss of Rap1GAP was not associated with the presence of the BRAF(V600E) mutation. In vitro, loss of Rap1GAP was sufficient to increase Rap1 activity in thyroid cells.

CONCLUSIONS

These data indicate that loss of Rap1GAP is a frequent event in PTC. The more frequent and greater down-regulation of Rap1GAP in PTCs compared with adenomas suggests a role for Rap1GAP depletion in the progression of human thyroid tumors, possibly through unrestrained Rap activity.

Cytology of sarcoma metastasizing to the thyroid: a case report

BACKGROUND

Metastatic tumors of thyroid are uncommonly reported from fine needle aspiration (FNA), although well documented in autopsy series. Soft tissue sarcomas metastasizing to the thyroid are even rarer.

CASE

A 30-year-old woman who was nown to have malignant fibrous histiocytoma arising in the soft tissues of the medial aspect of the ankle presented with a midline thyroid swelling, firm in consistency and moving with deglutition. FNA smears from the thyroid swelling showed discretely lying and loosely cohesive clusters of malignant cells admixed with benign thyroid follicular cells. The features were consirtent with metastases from a sarcoma.

CONCLUSION

The rare occurrence of a sarcoma metastasizing to the thyroid can be easily diagnosed by FNA cytology provided the primary is manifest and/or comparison with the primary or immunocytochemistry investigation is available.

Expression of galectin-3, cytokeratin 19, neural cell adhesion molecule and E-cadhedrin in certain variants of papillary thyroid carcinoma

The immunohistochemical expression of galectin-3 (Gal3), cytokeratin 19 (CK19), neural cell adhesion molecule (NCAM), and E-cadherin (Ecad) was evaluated to assess their use in diagnostics of papillary thyroid carcinoma (PTC). A total of 84 PTCs - 36 classical variants (cPTCs), 26 follicular variants (fPTCs), and 22 papillary microcarcinomas (mPTCs) were studied. Expression of Gal3 was found in 36/36 (100%) cPTCs, 24/26 (92%) fPTCs, and 19/22 (86%) mPTCs. CK19 expression was detected in 34/36 (94%) cPTCs, 17/26 (65%) fPTCs, and 13/22 (59%) mPTCs. Expression of NCAM was seen in 5/36 (14%) cPTCs, 7/26 (27%) fPTCs, and 9/22 (41%) mPTCs. Ecad expression was found in 23/36 (64%) cPTCs, 17/26 (65%) fPTCs, and 18/22 (82%) mPTCs. A significant difference in CK19 expression was observed between cPTC and both fPTC and mPTC (p < 0.001). Furthermore, extrathyroid tumor spread significantly correlated with both level of CK19 expression and loss of Ecad expression (p = 0.001, p = 0.04). Our findings suggest that Gal3 and CK19 are useful markers for PTC, although decreased CK19 expression in mPTC and fPTC must be considered. Furthermore, CK19 and Ecad may play a role in extrathyroid tumor spread.

Comparative topoisomerase IIa and ki 67 protein expression in papillary thyroid carcinoma based on tissue microarrays and image analysis

PURPOSE

Topoisomerase II alpha (Topo IIa gene location 17q21) is a nucleic enzyme involved in the DNA replication, transcription and chromosome topological formation. Topo IIa inhibition strategies include specific chemotherapeutic agents such as anthracyclines. Our aim was to investigate potential protein alterations of the enzyme comparing them to ki 67 proliferation marker expression in papillary thyroid carcinoma (PTC).

MATERIALS AND METHODS

Using tissue microarray (TMA) technology, 50 specimens consisting of histologically confirmed PTCs (n=20), multi-nodular goiters (n=20) and also normal thyroid epithelia (n=10) were cored and re-embedded in the final paraffin block. Immunohistochemical analysis was performed using monoclonal anti-Topo IIa and anti-ki 67 (MIB-1) antibodies. Digital image analysis assay was also applied for the evaluation of the protein expression results (Nuclear Labeling Index-NLI).

RESULTS

Topo IIa and ki 67 proteins were overexpressed in 4/20 (20%) and 14/20 (70%) cases, respectively. Concerning multi-nodular goiters, overexpression was observed in 2/20 and 4/20 specimens, respectively. Statistical association was assessed correlating ki 67 expression to pathology type, capsular invasion and also to vascular infiltration (p=0.001, p=0.008, and p=0.012, respectively). Topo IIa protein expression was strongly correlated only to capsular invasion (p=0.004). Overall expression of the examined markers demonstrated a medium concordance (kappa=0.27), but a strong association (p=0.001).

CONCLUSION

Topo IIa and also ki 67 overexpression are correlated to an aggressive phenotype in PTC. Topo IIa overexpression maybe is a reliable marker for a rational application of targeted chemotherapeutic strategies in some subgroups of patients.

[Thyroglobulin levels in needle lymph node cytology for the detection of papillary thyroid cancer recurrence]

BACKGROUND

During the detection of neck recurrence in patients with Papillary Thyroid Carcinoma (PTC), sometimes it is difficult to distinguish metastatic from inflammatory neck lymph nodes. The measurement of serum thyroglobulin (sTg) under thyroid hormone suppression therapy the presence of serum thyroglobulin antibodies (sAbTg), the diagnostic whole body scan and cytology can give false negative results. Measurement of thyroglobulin in the washout fluid from fine-needle aspiration biopsy (FNAB) of suspicious neck lymph nodes could improve the diagnostic accuracy.

AIM

To evaluate the usefulness of detecting Tg in lymph nodes (LTg) suspicious by ultrasonography (US) and compare it to cytology.

PATIENTS AND METHODS

Between the years 2004 and 2007 we prospectively studied 30 patients with PTC and cervical US findings of suspicious recurrence. LTg was assayed in US guided FNAB used for cytology.

RESULTS

Sixteen out of 30 patients underwent surgery using as selective criteria an LTg higher than sTg or a positive cytology. Surgery confirmed the presence of metastasis in all 15 patients with positive LTg (8 with positive cytology) and in 1 patient with negative LTg and positive cytology (a case with undifferentiated thyroid cancer). The sensitivity was 93.7% for LTg and 56.2% for cytology. We identified by LTg 3 of 6 patients with undetectable sTg and positive sAbTg.

CONCLUSIONS

The presence of LTg showed a higher sensitivity than cytology for the detection of cervical lymph node metastasis. This method is useful even in the presence of sAbTg.