Update regarding the role of PD-L1 in oncocytic thyroid lesions on cytological samples

AIMS

Several papers have shown that programmed death-ligand 1 (PD-L1) expression is a relevant predictive biomarker in anti-PD-L1 cancer immunotherapy. While its role in several human cancers is correlated with poor prognosis and resistance to anticancer therapies, in thyroid cancers the role of PD-L1 remains questionable. Few articles have studied PD-L1 in thyroid fine-needle aspiration cytology (FNAC), demonstrating a possible correlation with papillary thyroid carcinoma. However, its role in oncocytic thyroid lesions remains controversial. We accordingly examine the performance of PD-L1 immunostaining in liquid based cytology (LBC) from oncocytic lesions.

METHODS

From January 2019 to March 2021, 114 thyroid lesions diagnosed by FNAC from lesions with a predominant oncocytic component, were enrolled for evaluation by PD-L1 immunostaining on both LBC and corresponding histology samples.

RESULTS

The FNAC cohort included 51 benign (B, negative controls), 4 atypia of undetermined significance/follicular lesions of undetermined significance (AUS/FLUS), 57 follicular lesions (follicular neoplasm/suspicious for FN, FN/SFN) and 2 suspicious for malignancy (SFM) cases. Fifty-four cases (11B, 2 AUS/FLUS, 39 FN/SFN and 2 SFM) had histological follow-up including: 1B case resulted as a hyperplastic oxyphilic nodule in Hashimoto thyroiditis (HT), 10B as goitre, 2 AUS/FLUS cases as oncocytic adenomas (OAs); 39 FN/SFN included 27 OAs, 4 FA and 8 oncocytic follicular carcinoma (OFC). The two SFM cases were diagnosed on histopathology as OAs. Increased plasma membrane and cytoplasmic PD-L1 expression were found in 47 cases of the LBC cases (41.2%). Among the histological series, 67.3% of OAs and 75% of OFC had PD-L1 expression, while negative PD-L1 was found in hyperplastic oncocytic cells in HT. A positivity in more than 30% of the neoplastic cells was found in 72.9% of the cases including six OFC.

CONCLUSIONS

These data suggest that PD-L1 expression is expressed in oncocytic thyroid lesions. While weak PD-L1 expression failed to discriminate benign from malignant lesions, OFC demonstrated more intense cytoplasmic and membranous expression.

Prevalence of Excessive Iodine Intake in Pregnancy and Its Health Consequences: Systematic Review and Meta-analysis

The objective was to estimate the prevalence of excessive iodine intake in pregnant women and to investigate the consequences for maternal-fetal health. The systematic review was based on PRISMA. The search was conducted in September 2021 in LILACS, PubMed/MEDLINE, Science Direct, and SCOPUS databases. Observational studies that assessed excessive nutritional iodine status in pregnancy diagnosed by urinary iodine concentration and associated it with biomarkers of thyroid health function were included. Study selection, data extraction, and risk of biased evaluation were performed independently. Meta-analysis was calculated using a fixed and random effect model, and heterogeneity was assessed by the chi-square test. Meta-regressions were performed to identify the causes of heterogeneity using the Knapp and Hartung test. Nine studies were included in the systematic review, and eight in the meta-analysis. The prevalence of excessive iodine intake in 10,736 pregnant women in different regions of the world was 52%. The main implications for pregnant women were hypothyroxinemia, hypothyroidism, and hyperthyroidism. For the newborn, macrosomia and thyroid dysfunction. In addition, drinking water with high iodine intake contributed to excessive iodine intake. Therefore, the prevalence of iodine excess was 52%, with high heterogeneity among studies, explained by trimester of gestation and FT4 level; therefore, the farther the trimester of gestation and the lower the FT4, the higher the prevalence of iodine excess. PROSPERO Registration: CRD420206467 ( https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=206467 ).

US Features of the Parathyroid Glands: An Intraoperative Surgical Specimen Study

Purpose

This study aimed to evaluate the US features of the parathyroid glands (PTGs) using surgical specimens of normal PTGs obtained during thyroid surgery.

Materials and Methods

This study included 34 normal PTGs from 17 consecutive patients who underwent thyroid surgery between December 2020 and March 2021. All normal PTGs were histologically confirmed by intraoperative frozen-section biopsy for autotransplantation. Surgically resected parathyroid specimens were scanned in sterile normal saline using high-resolution US prior to autotransplantation. The US features of echogenicity (hyperechogenicity or hypoechogenicity), echotexture (homogeneous or heterogeneous), size, and shape (ovoid or round) were retrospectively evaluated. The echogenicity of the three PTGs was compared with that of the thyroid parenchyma of the resected thyroid specimens in two patients.

Results

All PTGs showed hyperechogenicity similar to that of gauze soaked in normal saline. Homogeneous hyperechogenicity was observed in 32/34 (94.1%) patients, and the echogenicity of the three PTGs was hyperechoic compared with that of the thyroid parenchyma. The long diameter of the PTGs ranged from 5.1 mm to 9.8 mm (mean, 7.1 mm) and the shape of the PTGs was ovoid in 33/34 (97.1%) patients.

Conclusion

The echogenicity of normal PTG specimens was consistently hyperechoic, and the small ovoid homogeneously hyperechoic structure was a characteristic US feature of the PTGs.

A First Report of Thyroid pneumatosis as a Complication of Ultrasound-Guided Thyroid Biopsy

BACKGROUND

Ultrasound-guided needle biopsies, including fine-needle aspirations (FNA) and core needle biopsies (CNB), have become an effective technique in the evaluation of thyroid nodules. In this report, we discuss the first reported case, to our knowledge, of thyroid pneumatosis after ultrasound-guided FNA.

CASE PRESENTATION

A 44-year-old woman underwent ultrasound-guided FNA in other hospitals after thyroid ultrasound revealed a solid lesion in the left lobe classified as TI-RADS 4. Two days later, this female presented to our hospital for an excision of a thyroid mass. Pre- and post-contrast CT scans of the thyroid showed extensive accumulation of gas in the thyroid gland and the retropharyngeal and retrotracheal space. A CT scan of the thyroid two days later revealed obvious absorption of thyroid gas and faint low-density nodules in the left lobe of the thyroid. The lesion was histopathologically confirmed as papillary carcinoma of the thyroid.

CONCLUSION

We thought the aforementioned issues originating from the limited imaging capacity of ultrasound in the context of thyroid biopsy. To avoid these limitations, we highlight the need to thoroughly examine the location of a lesion prior to thyroid biopsy to understand in detail the relationship between the lesion and the adjacent tissues, especially the proximity of the lesion to the trachea, the occurrence of coughing during a biopsy (indicating puncture of the trachea) is what operators need to be aware of so that they can manage such cases. On the other hand, we recommend that pre-operative use of CT before thyroid biopsy and especially if CT is needed anyway later for nodules evaluation before surgery to ensure the CT image quality.

Thyroid autoantibodies

Thyroid-stimulating hormone (TSH) receptor antibody (TSH-R-Ab or TRAb) testing plays a pivotal role in arriving at the aetiological diagnosis in patients with thyrotoxicosis. A positive test establishes the diagnosis of Graves' disease (GD) while a negative result in conjunction with imaging studies supports other possible aetiologies. In patients with GD, TRAb levels at diagnosis and at the time of withdrawal of antithyroid drugs can identify patients who are unlikely to achieve remission and guide clinical management decisions. We provide an algorithm that incorporates TRAb in the decision-making process for the management of thyrotoxicosis. The utility of TRAb in predicting the risk of fetal and neonatal thyroid dysfunction is established and widely accepted in guidelines. TRAb may also help in the diagnosis of Graves' orbitopathy, especially in euthyroid or hypothyroid patients and its role in guiding its management is evolving as a useful adjunct to the clinical parameters used in making therapeutic decisions.Anti-thyroid peroxidase antibodies (TPOAb) and anti-thyroglobulin antibodies (TgAb) indicate thyroid autoimmunity. The most common use of TPOAb is to identify patients at a higher risk of progression to treatment-requiring hypothyroidism. They also aid the diagnosis of immune thyroiditis and Hashimoto's encephalopathy. Thyroglobulin measurement is used to help guide differentiated thyroid cancer treatment. TgAb is used as an accompanying test with thyroglobulin measurement as its presence can interfere with the thyroglobulin assay. A negative TgAb result reduces the likelihood of, but does not exclude, interference with thyroglobulin assay.

Giant epidermal inclusion cyst of the thyroid: a rare occurrence

Epidermal inclusion cyst (EIC) of the thyroid is extremely rare in the clinical practice. A handful of cases have been documented in the past in the world literature. A giant EIC of the thyroid is hitherto unreported. This lesion may arise from the squamous metaplasia of the thyroid follicular cells. Though non-neoplastic, giant forms can cause compression of the vital structures of the neck. In the present case, we have described a giant epidermal inclusion cyst successfully managed with surgical management.

How we do it: 'tonsil swabs please' - an alternative use in open neck surgery

BACKGROUND

Thyroid and parathyroid surgery often involves the use of heated instruments for dissection. Whilst these are beneficial, accidental thermal damage to the exposed skin edges can occur, resulting in an unsatisfactory cosmetic outcome. Tonsil swabs can be used in head and neck surgery intra-operatively to control bleeding. This paper describes an alternative use for them in protecting wound edges during the procedure.

METHOD

Damp tonsil swabs are sutured onto the wound edges after the initial skin incision. They remain present for the duration of the surgery and are removed at the time of skin closure.

RESULTS

The tonsil swabs provide protection and help avoid accidental injury to the skin. No complications with this technique have been experienced.

CONCLUSION

This paper describes a simple, effective and practical technique for protecting the skin during neck procedures using resources readily available in a standard ENT operating theatre.

Comparing ultrasound assessment of thyroid nodules using BTA U classification and ACR TIRADS measured against histopathological diagnosis

INTRODUCTION

The British Thyroid Association (BTA) recommends ultrasound assessment of thyroid nodules using the U classification. The American College of Radiologists (ACR) recommend assessment with the Thyroid Imaging Reporting and Data System (TIRADS). We conduct the first UK study to compare these two systems.

METHODS

Ultrasound (US) reports of patients who underwent surgical excision of thyroid nodules over a 10-year period in one UK centre were reviewed. US findings were collected, and the classifications were retrospectively applied. The systems were compared to histopathological diagnosis.

RESULTS

308 nodules in 296 patients are included. 135 nodules (43.8%) were malignant. U classification showed sensitivity of 88.1% in recommending FNA, significantly higher than TIRADS at 73.3% (p = .0002). The U classification showed specificity of 41.6%, significantly lower than TIRADS at 64.2% (p=<0.0001). PPV between classifications at equivalent levels showed no significant difference at U3/TR-3 (p=.81), U4/TR-4 (p=.30) or U5/TR-5 (p=.90).

DISCUSSION

Classification systems enable risk stratification of potentially malignant thyroid nodules. This study shows BTA U classification has a higher sensitivity but lower specificity than TIRADS.

Is sonographic intra-nodular vascularity a reliable predictor of thyroid malignancy? A UK tertiary centre study

OBJECTIVE

British Thyroid Association 2014 guidelines emphasised ultrasound assessment of nodules. One ultrasonographic differentiator of debatable relevance is intra-nodular vascularity. This is the first UK study conducted to address this question.

METHODS

Ultrasound reports for thyroid surgery patients over 10 years were retrospectively reviewed. Reports documenting 'intra-nodular vascularity or flow' were analysed. Reports identifying peripheral vascularity only or no intra-nodular flow formed the control group. Concordance with final histology was used to determine the odds ratio for malignancy.

RESULTS

A total of 306 patients were included, and 119 (38.9 per cent) nodules demonstrated intra-nodular vascularity. Of these, 60 (50.4 per cent) were malignant compared with 42 per cent in the control group. Intra-nodular vascularity was not a statistically significant predictor of malignancy with an odds ratio of 1.39 (p = 0.18, 95 per cent confidence interval, 0.86-2.23).

CONCLUSION

Intra-nodular vascularity in isolation was not a reliable predictor of malignancy. This supports other world literature studies. Although intra-nodular flow should not be relied upon in isolation, interpretation in conjunction with other suspicious findings enhances the predictive value.

Considerations for the management of critical patients with thyroid disease

The role of the endocrine system in the homeostasis of all the body is essential, and has an impact on quality of life, prognosis and survival of patients. Although all the organs of this system are important, the thyroid gland is sizeable due to its easily accessible anatomical location and the variety of symptoms and signs that occur after it is affected. In the intensive care unit, knowledge of thyroid physiology and pathology is essential, due to the critical condition of patients and their multisystemic compromise, which is why this knowledge becomes an essential tool in the diagnostic arsenal to give a timely and effective management of these disorders. The objective of this review is to transmit in a timely and updated manner the necessary considerations for the optimal approach to patients with thyroid disease in the intensive care unit.

A Rare Case of Metastasis of Renal Clear Cell Carcinoma to the Thyroid Gland, Presenting as a Goiter Nodule, Three Years After Nephrectomy

Thyroid gland metastatic tumors are rare in clinical practice. Clear cell RCC is one of common metastatic tumors to thyroid. We here reported a case of incidentally found clear cell renal carcinoma metastasis to the thyroid gland 3 years after nephrectomy, in the thyroidectomy procedure performed for the patient due to the thyroid enlargement caused by multinodular goiter. A 65-year-old Iranian man with a history of multinodular goiter referred to our surgery clinic for thyroidectomy because of compressive effects on the trachea. Patient had a history of nephrectomy due to clear cell RCC 3 years ago. After thyroidectomy, gross and histological examination of thyroid revealed clear cell renal carcinoma metastasis to the thyroid gland in the setting of a multinodular goiter. The diagnosis was confirmed by immunohistochemistry staining. Patients with multinodular goiter are more prone to present with metastasis to thyroid gland if they have a history of malignancy, especially renal cell carcinoma.

Radiation exposure to the eyes and thyroid during C-arm fluoroscopy-guided cervical epidural injections is far below the safety limit

Background

The aim of this study was to evaluate radiation exposure to the eye and thyroid in pain physicians during the fluoroscopy-guided cervical epidural block (CEB).

Methods

Two pain physicians (a fellow and a professor) who regularly performed C-arm fluoroscopy-guided CEBs were included. Seven dosimeters were used to measure radiation exposure, five of which were placed on the physician (forehead, inside and outside of the thyroid protector, and inside and outside of the lead apron) and two were used as controls. Patient age, sex, height, and weight were noted, as were radiation exposure time, absorbed radiation dose, and distance from the X-ray field center to the physician.

Results

One hundred CEB procedures using C-arm fluoroscopy were performed on comparable patients. Only the distance from the X-ray field center to the physician was significantly different between the two physicians (fellow: 37.5 ± 2.1 cm, professor: 41.2 ± 3.6 cm, P = 0.03). The use of lead-based protection effectively decreased the absorbed radiation dose by up to 35%.

Conclusions

Although there was no difference in radiation exposure between the professor and the fellow, there was a difference in the distance from the X-ray field during the CEBs. Further, radiation exposure can be minimized if proper protection (thyroid protector, leaded apron, and eyewear) is used, even if the distance between the X-ray beam and the pain physician is small. Damage from frequent, low-dose radiation exposure is not yet fully understood. Therefore, safety measures, including lead-based protection, should always be enforced.

Multifocal papillary carcinoma of the thyroid with heterotopic ossification and extramedullary hematopoiesis associated with a lipomatous follicular nodule

Heterotopic ossification has been described in papillary thyroid carcinoma in association with high incidence of extrathyroidal invasion, multifocality, lymph node metastasis, and older age. Nevertheless, it has not been described as a specific subtype of papillary thyroid carcinoma, because of its rarity. We described the case of an 80-year-old female patient, with familial history of papillary thyroid carcinoma. In the annual screening examination, she was diagnosed with thyroid nodules. The patient was submitted to a thyroidectomy because the fine needle aspiration cytology was positive for malignancy according to the Bethesda classification. The surgical specimen analyses showed a multifocal papillary carcinoma with one major lesion in the left lobe measuring 0.9 cm, and two small lesions (0.4 cm and 0.2 cm) in the right lobe. Only the biggest lesion in the right lobe had the osteoid matrix with rare osteoclasts and fat metaplasia with progenitor cells. There was perineural invasion, but vascular invasion was not identified. The margins were free and there was no extrathyroidal extension. In the left lobe there was an oncocytic nodule and a lipomatous follicular nodule. In recent years there has been a significant increase in the diagnosis of thyroid cancer, mainly because of the finding of microcarcinomas as a result of many requests for cervical image exams. Future studies may define (i) whether papillary thyroid carcinoma with heterotopic ossification is a true histological variant; (ii) the causes of that alteration; and (iii) eventual follow-up implications.

A Multimodal and Pathological Analysis of a Renal Cell Carcinoma Metastasis to the Thyroid Gland 11 Years Post Nephrectomy

Thyroid lesions have a comprehensive differential diagnosis which include benign and malignant entities, such as metastases. However, metastases only account for a small percentage of thyroid lesions with renal cell carcinoma as the most common. Metastases to the thyroid pose a diagnostic dilemma as symptoms may not manifest for up to decades after removal of the renal cell carcinoma. Due to the nonspecific appearance on computed tomography and ultrasound, distinguishing metastases from primary thyroid malignancies is of the utmost importance for timely patient management. Our case demonstrates the importance of considering RCC metastases to the thyroid even years after nephrectomy to mitigate potential delays in diagnosis. We present the case of a 66-year-old male with a past medical history of renal cell carcinoma status post nephrectomy 11 years prior who demonstrated incidental thyroid abnormalities on positron emission tomography/computed tomography and ultrasound later confirmed as a metastasis of renal cell carcinoma.

Fluoride Exposure in Early Life as the Possible Root Cause of Disease In Later Life

Fluoride, one of the most celebrated ingredients for the prevention of dental caries in the 20th century, has also been controversial for its use in dentifrices and other applications. In the current review, we have concentrated primarily on early-life exposure to fluoride and how it may affect the various organs. The most recent controversial aspects of fluoride are related to toxicity of the developing brain and how it may possibly result in the decrease of intelligence quotient (IQ), autism, and calcification of the pineal gland. In addition, it has been reported to have possible effects on bone and thyroid glands. If nutritional stress is applied during a critical period of growth and development, the organ(s) and/or body will never recover once they pass through the critical period. For example, if animals are force-fed during experiments, they will simply get fat but never reach the normal size. Although early-life fluoride exposure causing fluorosis is well reported in the literature, the dental profession considers it primarily as an esthetic rather than a serious systemic problem. In the current review, we wanted to raise the possibility of future disease as a result of early-life exposure to fluoride. It is not currently known how fluoride will become a cause of future disease. Studies of other nutritional factors have shown that the effects of early nutritional stress are a cause of disease in later life.

[Elastography in the evaluation of thyroid nodules]

BACKGROUND

Thyroid nodules are a very common pathology in clinical practice and in imaging studies. Autopsy results indicate a 50% prevalence of thyroid nodules greater than 1 cm in patients with no clinical symptomatology. The goal is to evaluate the accuracy of elastography in the evaluation of thyroid nodules with suspicion of malignancy by comparing the results obtained in qualitative and semi-quantitative elastography with the cytopathological study obtained by BAAF of thyroid nodules and The TI-RADS system.

METHODS

We included male or female patients over 18 years old, entitled to IMSS, with diagnosis of one or more thyroid nodules, sent to the ultrasound service for FNA and histopathological report at the end of the study. In the statistical analysis, values of sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) were obtained.

RESULTS

The results showed that the qualitative elastography by the Asteria Score presents a sensitivity of 86% and a specificity of 53%, PPV of 36% and NPV of 92% , for the semiquantitative elastography a sensitivity of 40%, specificity of 87%, PPV of 50% and NPV of 82%.

CONCLUSIONS

The elastography in its qualitative and semicuantitative mode are useful to help determine the possibility of malignancy of thyroid nodules as an additional element to ultrasound, but it does not replace the citopathologic result or other diagnostic tests, so it should not be taken as a single test. Additionally the high result of NPV is useful to dismiss the possibility of malignancy.

Clinical Significance of an Unusual Variation: Anomalous additional belly of the sternothyroid muscle

The infrahyoid muscles are involved in vocalisation and swallowing; among these, the sternothyroid muscle is derived from the common primitive sheet. The improper differentiation of this muscle may therefore result in morphological variations. We report an unusual variation found during the dissection of a 65-year-old male cadaver at the Sri Manakula Vinayagar Medical College, Madagadipet, Pondicherry, India, in 2015. An anomalous belly of the right sternothyroid muscle was observed between the internal jugular (IJ) vein and the internal carotid artery with an additional insertion into the tympanic plate and petrous part of the temporal bone and the presence of a levator glandulae thyroideae muscle. The anomalous muscle may compress the IJ vein if it is related to the neurovascular structures of neck; hence, knowledge of variations of the infrahyoid muscles can aid in the evaluation of IJ vein compression among patients with idiopathic symptoms resulting from venous congestion.

A paired comparison analysis of third-party rater thyroidectomy scar preference

OBJECTIVE

To determine the length and position of a thyroidectomy scar that is cosmetically most appealing to naïve raters.

METHODS

Images of thyroidectomy scars were reproduced on male and female necks using digital imaging software. Surgical variables studied were scar position and length. Fifteen raters were presented with 56 scar pairings and asked to identify which was preferred cosmetically. Twenty duplicate pairings were included to assess rater reliability. Analysis of variance was used to determine preference.

RESULTS

Raters preferred low, short scars, followed by high, short scars, with long scars in either position being less desirable (p < 0.05). Twelve of 15 raters had acceptable intra-rater and inter-rater reliability.

CONCLUSION

Naïve raters preferred low, short scars over the alternatives. High, short scars were the next most favourably rated. If other factors influencing incision choice are considered equal, surgeons should consider these preferences in scar position and length when planning their thyroidectomy approach.

Organ Atrophy Induced by Sorafenib and Sunitinib - Quantitative Computed Tomography (CT) Evaluation of the Pancreas, Thyroid Gland and Spleen

Background

To evaluate organ atrophy induced by sorafenib and sunitinib, we retrospectively reviewed the CT scans of renal cell carcinoma (RCC) patients receiving molecular targeted therapy (MTT) using sorafenib or sunitinib, and performed volumetric analysis of the pancreas, thyroid gland, and spleen.

Material/Methods

Thirteen RCC patients receiving MTT were assigned as the evaluation cases (MTT group), while thirteen additional RCC patients not receiving MTT were retrieved as the Control group. We evaluated the baseline and follow-up CT studies. The volume of the three organs estimated by CT volumetry was compared between the baseline and follow-up CTs. The atrophic ratio of the organ volume in the follow-up CT to that in the baseline CT was calculated, and compared between the MTT and Control groups.

Results

All measured organs in the MTT group showed statistically significant volume loss, while no significant change was observed in the Control group. Mean atrophic ratio in the MTT group was 0.74, 0.58, and 0.82 for the pancreas, thyroid and spleen, respectively. The differences in atrophic ratios between both groups were all statistically significant (P<0.05).

Conclusions

Single-agent sorafenib or sunitinib therapy induced statistically significant atrophy in the pancreas, thyroid, and spleen.

Analysis of the incidence and factors predictive of inadvertent parathyroidectomy during thyroid surgery

BACKGROUND

Inadvertent (or incidental) parathyroidectomy can occur during thyroidectomy. However, the factors associated with inadvertent parathyroidectomy remain unclear. This study aimed to report the rate of inadvertent parathyroidectomy during thyroidectomy and associated risk factors.

METHODS

Variables including fine needle aspiration cytology findings, age, sex, thyroid weight, concurrent neck dissection, extent of thyroidectomy, and the presence of cancer and parathyroid tissue within the specimen were recorded for 266 patients. The incidence of post-operative hypocalcaemia was also recorded. Univariate and multivariate analysis were performed to identify factors associated with inadvertent parathyroidectomy.

RESULTS

The inadvertent parathyroidectomy rate was 16 per cent. Univariate analysis revealed that cancer and concurrent neck dissection predicted inadvertent parathyroidectomy. On multivariate analysis, only concurrent neck dissection remained an independent predictor of inadvertent parathyroidectomy: it was associated with a fourfold increase in inadvertent parathyroidectomy.

CONCLUSION

The inadvertent parathyroidectomy rate was 16 per cent and concurrent neck dissection was identified as an independent predictor of inadvertent parathyroidectomy.

Prominent Cold Nodule in Multinodular Goiter Revealed to Be Thyrolipoma: A Case Report

The presence of adipose tissue in the thyroid gland is a rare finding. Thyrolipoma or adenolipoma of the thyroid is a benign, encapsulated lesion of the thyroid composed of variable amounts of fat and glandular elements. This report presents a case of thyrolipoma in a 69-yr-old female presenting with neck swelling and respiratory distress. Differential diagnosis of the fat-containing thyroid lesion is also presented. Differentiation of the condition from similar lesions is necessary for accurate diagnosis of thyrolipoma.

Ectopic mediastinal thyroid tissue with a normally located thyroid gland

Ectopic thyroid tissue (ETT) is a rare entity and a challenging differential diagnosis. This is a report of a case of a mediastinal mass that was found to be an ectopic mediastinal thyroid tissue, in a 77-year-old woman who was admitted to our hospital for breast cancer management. The mediastinal mass was identified in the postsurgical computed tomography (CT) scan of the chest and was suspected as mediastinal lymph node metastasis. A CT-guided percutaneous transthoracic punch biopsy (CT-TPB) proved to be an adequate diagnostic tool to exclude malignancy and provide a definite diagnosis of the mediastinal mass. We find that CT-guided punch biopsy as a useful diagnostic alternative enabling histopathological specimens to be obtained from mediastinal masses and lymph nodes suspected of malignancy.

Frequency of thyroid incidentalomas in Karachi population

Objectives: The aim of this study was to determine frequency of thyroid incidentalomas (TI) through ultrasound (US) and its association with age, gender and ethnicities.

Methods: It was a cross-sectional study. Total 269 adults who were asymptomatic for thyroid disease aged 21 years and above underwent ultrasound examination of their thyroid.

Results: Frequency of TI found was 21%. TI was detected in 25% of females and 16% males (P= 0.078). 61% had thyroid nodules (TNs) in one lobe (right, left or isthmus) and 39% had TNs in more than one location. About 55% had single TN and 45% had multiple TNs. 38% had TNs greater than 1cm while 57% had TNs smaller than 1 cm. 5% had TNs greater and smaller than 1 cm. TI was equally common in individuals of different ethinicities (P= 0.758).

Conclusion: Frequency of thyroid incidentalomas found in our study was higher than most of the other iodine sufficient states. Unlike other studies, incidentalomas were equally common in both the genders of our study. This may be due to the previous iodine deficient status of Pakistan which was prevalent. However further studies on the same topic will help us in identifying the correct status of thyroid incidentalomas if Pakistan retains it’s status as an iodine sufficient state.

Detection of thyroid autoimmunity markers in euthyroid women with polycystic ovary syndrome: a case-control study from syria

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies in women in reproductive age. In many cases, PCOS is associated with infertility and increased risk of miscarriage. Recent studies have detected the presence of several organ specific and nonspecific autoantibodies in women with PCOS.

OBJECTIVES

The aim of this study was to evaluate the prevalence and levels of thyroid antibodies in euthyroid women with PCOS in Syria.

PATIENTS AND METHODS

This study included 56 euthyroid women with PCOS and 30 healthy women as a control group. PCOS was defined according to the revised 2003 Rotterdam criteria. Thyroid function was evaluated by measurement of serum TSH and FT4 levels. Antithyroid peroxidase and antithyroglobulin antibodies (anti-TPO and anti-TG, respectively) were detected as markers for thyroid autoimmunity. All parameters were measured using electrochemiluminescence immunoassay.

RESULTS

Women with PCOS had higher serum levels of anti-TPO in comparison to controls (39.9 ± 59.5 and 18.9 ± 11.2 IU/mL, respectively; P < 0.05) and no significant difference was found in serum levels of anti-TG, TSH, or FT4 between the two groups. Patients with PCOS had a higher prevalence of positive results for anti-TG and/or anti-TPO in comparison to controls (28.6% and 3.3%, respectively; P<0.05), anti-TPO alone (19.6% and 3.3%, respectively; P < 0.05) and anti-TG alone (21.4% and 3.3%, respectively; P < 0.05). No significant associations were found between antibodies and studied hormones.

CONCLUSIONS

High prevalence of thyroid antibodies in euthyroid patients with PCOS refers to the importance of investigation for thyroid autoimmune state in those patients.

Imaging mass spectrometry in papillary thyroid carcinoma for the identification and validation of biomarker proteins

Direct tissue imaging mass spectrometry (IMS) by matrix-assisted laser desorption ionization and time-of-flight (MALDI-TOF) mass spectrometry has become increasingly important in biology and medicine, because this technology can detect the relative abundance and spatial distribution of interesting proteins in tissues. Five thyroid cancer samples, along with normal tissue, were sliced and transferred onto conductive glass slides. After laser scanning by MALDI-TOF equipped with a smart beam laser, images were created for individual masses and proteins were classified at 200-µm spatial resolution. Based on the spatial distribution, region-specific proteins on a tumor lesion could be identified by protein extraction from tumor tissue and analysis using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Using all the spectral data at each spot, various intensities of a specific peak were detected in the tumor and normal regions of the thyroid. Differences in the molecular weights of expressed proteins between tumor and normal regions were analyzed using unsupervised and supervised clustering. To verify the presence of discovered proteins through IMS, we identified ribosomal protein P2, which is specific for cancer. We have demonstrated the feasibility of IMS as a useful tool for the analysis of tissue sections, and identified the tumor-specific protein ribosomal protein P2.

Composite follicular variant of papillary carcinoma and mucoepidermoid carcinoma of thyroid gland: a case report

A 50-yr-old male presented a thyroid mass with dysphasia and hoarseness. He underwent total thyroidectomy and neck node dissection. Pathologically, the tumor had two distinct tumor components with intermingled areas: follicular variant of papillary carcinoma and mucoepidermoid carcinoma. Mucoepidermoid carcinoma composed of columnar cells, mucocytes, and squamoid cells showing solid and cystic lesion. Several small cysts lined by benign ciliated columnar epithelia suggesting that this tumor had originated from solid cell nest were seen around the tumor. By immunohistochemistry, columnar cells and squamoid cells in mucoepidermoid carcinoma were positive for cytokeratin but negative for thyroglobulin, TTF-1 and calcitonin. Positivity of p63 was seen in squamoid cells and basal cells of cysts. Some mucocytes are CEA positive. Tumor cells of papillary carcinoma are positive for TTF-1, thyroglobulin but negative for CEA, calcitonin and p63.

NDRG1 protein overexpression in malignant thyroid neoplasms

OBJECTIVES

The aim of this study was to examine the expression of the N-myc downstream-regulated gene 1 protein in benign and malignant lesions of the thyroid gland by immunohistochemistry.

INTRODUCTION

N-myc downstream-regulated gene 1 encodes a protein whose expression is induced by various stimuli, including cell differentiation, exposure to heavy metals, hypoxia, and DNA damage. Increased N-myc downstream-regulated gene 1 expression has been detected in various types of tumors, but the role of N-myc downstream-regulated gene 1 expression in thyroid lesions remains to be determined.

METHODS

A tissue microarray paraffin block containing 265 tissue fragments corresponding to normal thyroid, nodular goiter, follicular adenoma, papillary thyroid carcinoma (classical pattern and follicular variant), follicular carcinoma, and metastases of papillary and follicular thyroid carcinomas were analyzed by immunohistochemistry using a polyclonal anti- N-myc downstream-regulated gene 1 antibody.

RESULTS

The immunohistochemical expression of N-myc downstream-regulated gene 1 was higher in carcinomas compared to normal thyroid glands and nodular goiters, with higher expression in classical papillary thyroid carcinomas and metastases of thyroid carcinomas (P < 0.001). A combined analysis showed higher immunohistochemical expression of NDRG1 in malignant lesions (classical pattern and follicular variant of papillary thyroid carcinomas, follicular carcinomas, and metastases of thyroid carcinomas) compared to benign thyroid lesions (goiter and follicular adenomas) (P = 0.043). In thyroid carcinomas, N-myc downstream-regulated gene 1 expression was significantly correlated with a more advanced TNM stage (P = 0.007) and age, metastasis, tumor extent, and size (AMES) high-risk group (P = 0.012).

CONCLUSIONS

Thyroid carcinomas showed increased immunohistochemical N-myc downstream-regulated gene 1 expression compared to normal and benign thyroid lesions and is correlated with more advanced tumor stages.

Primary T-cell lymphoma of the thyroid associated with Hashimoto's thyroiditis, histologically mimicking MALT-lymphoma

Most of thyroid lymphomas are B-lineage, and T-cell lymphomas are rare. Here, we report a case of primary thyroid T-cell lymphoma associated with Hashimoto's thyroiditis. A 48-yr-old woman presented with incidentally found neck mass. Histologically, the resected right lobe of the thyroid was replaced by monomorphic small atypical lymphoid cells with lymphoepithelial lesion-like change, most of which were immunoreactive for CD3, CD8, betaF-1, and TIA-1. Peripheral T-cell lymphoma, unspecified, was finally diagnosed after molecular study for TCR-gamma gene rearrangement. This is the second case of cytotoxic T-cell lymphoma reported in the thyroid gland so far. Unique association between thyroid follicles and neoplastic lymphocytes may be characteristic feature of this type of T-cell lymphoma.

Primary thyroid tuberculosis

In India, it is estimated that more than 40% of the adults are infected with tuberculosis bacilli and every year 2 million people develop tuberculosis and nearly 500,000 die from it1. But, tuberculosis of the thyroid gland occurs only rarely. Since extra-pulmonary tuberculosis is now seen relatively more frequently, the existence of this condition should be recognized when goitres are being treated. We present a case of right thyroid nodule associated with low grade fever and weight loss. No signs and symptoms of hypothyroidism or hyperthyroidism were present. Patient did not have any other tuberculosis focus. Routine investigation and chest X-ray were normal. Sputum for Acid Fast Bacilli was negative. Fine Needle Aspiration Cytology and Contrast Enhanced Computed Tomography led to a diagnosis of Primary Thyroid Tuberculosis in a euthyroid patient. Patient responded well to Anti tubercular Drug Therapy along with repeated aspiration.

Two patients with metastasis of cancer to other neoplasm: A thyroid carcinoma metastatic to a lung carcinoma and a gastric carcinoma metastatic to a thyroid adenoma

Two patients with rare cancer-to-neopiasm metastasis are presented. One patient was a 69-year-old woman who had undergone gastrectomy for gastric cancer 10 months previously and died of generalized metastases. An autopsy revealed generalized metastases of the gastric carcinoma, together with a cystic, hemorrhagic thyroid tumor measuring 2.0 cm in diameter. Histologically, the thyroid tumor was an oxyphilic adenoma with multiple metastatic foci of gastric adenocarcinoma. Because no metastasis was found in the background thyroid tissue, this metastasis might have developed specifically and not by chance, most likely due to the rich vascularity and good circulation of the thyroid adenoma. The other patient was an 82-year-old man who had undergone total thyroidectomy for thyroid cancer 6 years previously. An abnormal lung shadow was found on a chest radiograph during postoperative follow-up. Transbronchial biopsy of the lung tumor revealed a squamous-cell carcinoma. The resected lung tumor measured 2.7 cm in diameter, with small foci of metastatic papillary carcinoma of the thyroid gland and multiple small metastases in the background lung tissue, indicating that the metastases to lung cancer had occurred by chance. Metastasis of cancer to other neoplasms is discussed, and a review of the literature is presented.

Ectopic thymic tissue in the thyroid gland

A case of ectopic thymic tissue of the thyroid in a 30-year-old woman with Graves' disease is reported. The thyroidectomy specimen, removed because of failure of medical therapy, showed a continuous track of thymic tissue extending from the center of the gland to the capsule along an interiobular septum. This finding is unique, and the histogenesis of this ectopic thymic tissue is discussed.Endocr Pathol 4:162-164, 1993.

Localized adiposity of the thyroid, clinically mimicking an adenoma

A case of localized adiposity of the thyroid in a 35-year-old woman with a long history of steroid therapy for nephrotic syndrome is reported. A well-demarcated yellowish mass measuring 2 cm in diameter was found in the upper portion of the right lobe of the thyroid. Microscopically, this lesion was composed of mature adipose tissue partially mixed with thyroid tissue and had no distinct capsule. The nontumorous thyroid tissue showed features of Hashimoto's thyroiditis. At least two factors-hamartomatous malformation and metabolic disturbance-may be involved in the histogenesis of this localized adiposity.

Thyroid thymoma in childhood

A nontoxic thyroid nodule was detected in a female infant soon after birth. At 4 years of age, the nodule was removed. Histological examination disclosed a Iobulated spindle-cell neoplasm with focal epithelioid differentiation. The tumor demonstrated diffuse immunopositivity for low-molecular-weight keratins with scattered cells staining for S- 100 protein or leukocyte common antigen; the tumor was negative for calcitonin and thyroglobulin. By electron microscopy, the spindle-shaped cells contained bundles of intracytoplasmic tonofilaments and desmosomes. The light- and electron-microscopical features and immunohistochemical profile of this tumor were those of the recently described primary thyroid thymoma. Thymoma should be considered as a possible, albeit rare, cause of a thyroid mass in infancy or childhood.