Intrathyroidal Location Research Articles

Primary hyperparathyroidism with intrathyroidal location of parathyroid adenoma

Primary hyperparathyroidism is a common endocrine disease with high morbidity and mortality from all causes. The disease can be asymptomatic and for a long time remain undiagnosed, which leads to untimely surgical treatment, increases the risks of development and progression of severe disabling complications and worsens patients prognosis. In clinical practice there are certain difficulties in diagnosing this pathology. One of the urgent problems is the search for the source of parathyroid hormone hyperproduction, especially in case of atypical location of paraаdenoma. The most common atypical locations of altered parathyroid glands are thymus, retroor paraesophageal space, retropharyngeal space, mediastinum and thyroid gland. The frequency of intrathyroidal masses of parathyroid glands, in the thyroid parenchyma or under its capsule, ranges on average from 2 to 3%, but according to some authors can reach 18–22%. With such localization of paraadenomas there is a need for their differential diagnosis, first of all, with nodular formations of the thyroid gland. In addition, the absence of additional laboratory studies parathormone and calcium blood levels does not allow timely suspicion of the disease, and cytologic examination of the material obtained by fine-needle aspiration puncture biopsy does not allow reliable differentiation of the altered parathyroid gland. This article presents a clinical case of a patient with primary hyperparathyroidism with intrathyroidally located parathyroid adenoma, for a long time long identified as a “nodular goiter,” and provides a brief review of the methods that identify an intrathyroidally located parathyroma. Despite the abundance of diagnostic methods in visualization of intrathyroidal parathyroid glands, today the most appropriate seems to be expert ultrasound examination with assessment of the parathyroid hormone level in a washout after fine-needle aspiration, supplemented, if necessary, by scintigraphy and single-photon emission computed tomography combined with computed tomography or multispiral computed tomography.

7387 A Rare Case Of Concomitant Intrathyroidal Parathyroid Carcinoma With Osteitis Fibrosa Cystica, Masquerading As Oncocytic Thyroid Carcinoma - A Post-operative Diagnosis

Abstract Disclosure: Y. Koh: None. D.E. Chew: None. T.P. Quek: None. Introduction: Parathyroid carcinoma is a rare form of malignancy. An intrathyroidal location of parathyroid carcinoma further complicates the diagnosis as it may be mistakenly presumed to be of thyroid origin instead. We present a case report of an intrathyroidal parathyroid carcinoma which was diagnosed post-total thyroidectomy. Clinical case: A 72-year-old lady was found to have an intrathyroidal mass after presenting with unintentional weight loss and chronic constipation. Ultrasound of the neck showed a 4.0 x 2.9cm markedly hypoechoic solid mass in the mid-lower right thyroid lobe. Fine needle aspiration of the mass was suspicious for an oncocytic neoplasm. She underwent total thyroidectomy with central neck dissection for concerns of oncocytic thyroid carcinoma. Intraoperatively, a 4cm right hard intrathyroidal nodule invading into the right recurrent laryngeal nerve was observed. All 4 parathyroids were identified and preserved. Post-operatively, routine biochemistry to monitor for hypocalcemia showed hypercalcemia instead. This quickly transitioned into hypocalcemia on post-operative day 4, with biochemistry supportive of hungry bone syndrome [adjusted calcium 2.05mmol/L [normal range (NR) 2.15-2.5], phosphate 0.6mmol/L (NR 0.8-1.4), PTH 8.2pmol/L (NR 0.8-6.8), 25-OH vitamin D 18ug/L (NR 30-100)]. She was started on oral calcium carbonate, calcitriol and cholecalciferol aiming for normocalcemia. Evidence for underlying primary hyperparathyroidism were sought for, which showed osteitis fibrosa cystica, severe osteoporosis and an ossifying fibroma of the mandible, suggesting underlying hyperparathyroidism-jaw tumour-syndrome. The intra-operative histology was reported as oncocytic carcinoma with angio- and perineural invasion, presumed to be thyroid in origin. Given our suspicion of underlying primary hyperparathyroidism, we requested our pathology colleagues to perform additional immunochemical stains, which stained diffusely positive for parathyroid hormone, GATA3 but were negative for thyroglobulin, thyroid transcriptor factor-1, confirming its parathyroid origin. Her hungry bone syndrome resolved 22 weeks post-operatively. Till present (14 months post-operatively), her calcium and PTH levels remain normal and ultrasound of the neck did not reveal any evidence of recurrence. She declined genetic screening. Clinical Lesson: A high index of suspicion is required for the diagnosis of parathyroid carcinoma. In a patient who presents with constitutional symptoms and a neck mass, it is imperative to consider parathyroid disease as a differential diagnosis. A lesion with oncocytic morphology may be of parathyroid or thyroid origin, and the use of immunochemical stains can help differentiate them. Effective communication between clinicians and pathologists is essential in clinching the correct cytopathological diagnosis. Presentation: 6/3/2024

A new histopathological location of parathyroid gland with high possibility of unintended parathyroidectomy.

Unintended parathyroidectomy occasionally happens despite meticulous capsular dissection and the histopathological location of removed parathyroid glands were traditionally classified as extracapsular, subcapsular, and intrathyroidal location. This study aimed to investigate the new histopathological location of parathyroid gland with high possibility of unintended parathyroidectomy that was difficult to be found with naked eye despite capsular dissection. This study investigated unintended parathyroidectomy that occurred in 743 patients who received thyroid surgery by reviewing pathology reports and slides. The histopathological location of unintentionally removed parathyroid glands was classified as intracapsule and extracapsule, and the intracapsular glands were further classified as completely buried in the thyroid parenchyme, partially buried, and subcapsular locations. The incidence of unintended parathyroidectomy was 12.8%. Among the 103 unintentionally removed parathyroid glands, 74 (71.8%) were found intracapsular and 29 were extracapsular. Among the intracapsular glands, 57 (55.4%) parathyroid glands were found in difficult locations such as completely buried (40.8%) and partially buried (14.6%). The partially buried parathyroid gland can act as a risk factor for unintended parathyroidectomy comparable to intrathyroidal parathyroid gland despite the surgeon's best effort with meticulous capsular dissection. However, continued advances in visualizing technique such as autofluorescence imaging may lower the chance of incidentally removed partially buried parathyroid glands in the future.

Parathyroid adenoma: multimodal diagnosis capabilities: A retrospective study

Background. Primary hyperparathyroidism is a common endocrinological disease caused mainly by parathyroid adenoma. The main treatment method is surgery (parathyroidectomy). Therefore, the exact determination of adenoma localization is crucial.
 Aim. To evaluate the current possibilities of multimodal diagnosis of parathyroid adenomas.
 Materials and methods. A retrospective analysis of 49 patients with primary hyperparathyroidism aged 24 to 82 (median 57.9 years) was performed. Modern radionuclide and hybrid technologies were used for topical diagnosis and metabolic assessment of parathyroid adenomas: scanning, single-photon emission computed tomography, single-photon emission computed tomography combined with computed tomography, positron emission tomography combined with computed tomography with 18F-deoxyglucose and 18F-choline. The diagnosis of primary hyperparathyroidism was confirmed by a biochemical blood test: the level of parathyroid hormone and ionized and total calcium.
 Results. The study included 43 (87.8%) females and 6 (12.2%) males. The female/male ratio was 7.2:1. Most cases (78.1%) were the hypercalcemic type of primary hyperparathyroidism, and the normocalcemic type was diagnosed in 21.9% of patients. The mean parathyroid hormone level was 145.43 pg/mL, exceeding the reference values by 2.2 times. Parathyroid hormone concentration in patients with primary hyperparathyroidism was 156.38 pg/mL, and mean ionized and total blood calcium levels were 1.43 and 3.04 mmol/L, respectively. The asymptomatic type occurred in 76.7% of patients. The symptomatic type of hyperparathyroidism had 23.3%, manifested with nephrolithiasis, pancreatitis, and bone lesions. Parathyroid adenomas were more often located in the left lobe (42.9%). In 77.6% of patients with primary hyperparathyroidism, solitary adenomas were detected. Ectopia of the parathyroid glands was detected in 16.3% of patients, with intrathyroidal location in the left lobe being the most common. Rare locations include the anterior and posterior mediastinum and the esophageal wall.
 Conclusion. Modern diagnostic multimodal options based on radionuclide and hybrid technologies are crucial in the personalized treatment of primary hyperparathyroidism.

Primary hyperparathyroidism in children

Primary hyperparathyroidism (PHPT) is an endocrine disorder characterized by excessive secretion of parathyroid hormone (PTH) with upper-normal or elevated blood calcium levels due to primary thyroid gland pathology. PHPT is a rare pathology in children, with a prevalence of 2-5:100,000 children according to the literature. Due to the non-specificity of clinical manifestations at onset (nausea, vomiting, abdominal pain, emotional lability), the disease may remain undiagnosed for a long time. To study the features of the course and molecular genetic basis of primary hyperparathyroidism in children. Retrospective observational study of 49 patients diagnosed with primary hyperparathyroidism. All patients underwent a comprehensive laboratory-instrumental and molecular genetic study at the Institute of Pediatric Endocrinology, Endocrinology Research Center of Russia in the period 2014-2022. The first clinical symptoms of PHPT were noted at the age of 13.8 years [10.6; 1 5.2], among which fatigue, headaches, dyspepsia, lower limb pain, and fractures were the most common. The age of diagnosis was 15.81 years [13.1; 16.8], all children were found to have high levels of PTH, total and ionized calcium, with hypophosphatemia in 93.9% of patients (n=46) and hypercalciuria in 43% (n=21). Five out of 49 patients (10.2%) were found to have ectopy of the thyroid: 3 showed an intrathyroidal location, 2 in the mediastinal region. Molecular genetic study revealed mutations in 32.7% of patients (n=16, CI (21; 47)), mutations inMEN1being the most frequent (n=11). Pathogenic variants inCDC73were detected in 3patients,RET -in 2. Among the operated 39 patients, adenoma of the thyroid was detected in 84.6% of cases (n=33), hyperplasia in 7.7% (n=3), atypical adenoma in 5.1% (n=2), carcinoma in 5.1% of cases (n=2). The paper presents the peculiarities of the course and the results of molecular genetic study of pediatric PHPT. This sample is the largest among those published in the Russian Federation.

Atypical parathyroid tumor: clinical and parathyroid hormone response to surgical treatment.

Primary hyperparathyroidism (PHPT) is caused by typical adenoma (TA), multiglandular disease (MD), or parathyroid carcinoma (PC), and in a smaller percentage of cases by atypical parathyroid tumor (APT). The objective of this study is the retrospective analysis of clinical features and parathyroid hormone (PTH)/calcium response to surgery in patients who underwent parathyroidectomy for symptomatic PHPT with histological evidence of APT. We retrospectively reviewed our institutional experience in the management of PHPT from January 2016 to December 2021 focusing on those patients presenting APTs. We analyzed the clinical features of this disease and PTH/calcium response to surgical treatment in APTs compared to the other pathological conditions causing PHPT. In a cohort of 125 patients with PHPT we found 112 TAs (89.6%), 6 APTs (4.8%), 6 PCs (4.8%), and only 1 MD (0.8%). APTs in comparison to other parathyroid diseases showed peculiar features such as adhesion to the surrounding structures and a frequent intrathyroidal location, which may justify thyroid loboistmectomy adopted in most of the observed cases. APTs showed significantly higher preoperative PTH values compared to TA + MD and were relevant to PC. Due to its rarity, there is a lack of specific indications in the management of APTs. Biochemical features observed in APT and PC can be related to similar biological behavior. However, some specific features observed preoperatively in some cases of PHPT might suggest presence of an APT, which could be helpful mostly in surgical and postoperative management. Further studies are required to confirm the results of the present preliminary report.

Giant parathyroid tumours in primary hyperparathyroidism: a systematic review.

Giant parathyroid adenoma (GPA) can present with severe biochemical derangement similar to the clinical presentation of parathyroid carcinoma (PC). This study aims to present the current evidence on surgical management of GPAs in primary hyperparathyroidism. A systematic review of the literature on GPAs was conducted following the PRISMA guidelines. Data on clinical, biochemical, preoperative diagnostic, and surgical methods were analysed. Sixty-one eligible studies were included reporting on 65 GPAs in eutopic, ectopic mediastinal, and intrathyroidal locations (61.5%, 30.8%, and 7.7%, respectively). A palpable neck mass was present in 58% of GPAs. A total of 90% of patients had symptoms including fatigue, skeletal pain, pathological fracture, nausea, and abdominal pain. Ninety percent of patients had significant hypercalcaemia (mean 3.51mmol/L; range: 2.59-5.74mmol/L) and hyperparathyroidism with PTH levels on average 14 times above the upper limit of the normal reference. There was no correlation between the reported GPA size and PTH nor between GPA weight and PTH (p = 0.892 and p = 0.363, respectively). Twenty-four percent had a concurrent thyroidectomy for suspicious features, intrathyroidal location of GPA, or large goitre. Immunohistochemistry such as Ki-67, parafibromin, and galectin-3 was used in 18.5% of cases with equivocal histology. Ninety-five percent of GPAs were benign with 5% reported as atypical adenomas. The reported data on GPAs are sparse and heterogeneous. In GPAs with suspicious features for malignancy, en bloc resection with concurrent thyroidectomy may be considered. In the presence of equivocal histological features, ancillary immunohistochemistry is advocated to differentiate GPAs from atypical adenomas and PCs.

Diagnosis and management of Intratyroid Ectopic Thymus.

Intrathyroidal ectopic thymus (IET) is a rare benign condition caused by the aberrant thymic migra tion during embryogenesis. It is usually incidentally diagnosed as a thyroid nodule. To report the intrathyroidal location of ectopic thymic tissue and to describe the ultrasound findings in children. Retrospective descriptive review of the medical charts and thyroid ultrasound studies of children with nodular images in the thyroid gland, in a third level national pediatric hospital, from January 2010 to August 2017. Solid hypoecogenic intrathyroid lesions with multiple linear tracts or hyperechogenic points that did not change their characteristics during fo llow-up were considered intrathyroidal thymos. The ultrasound follow-up was performed every 4-6 months. The ultrasound characteristics of the lesions (location, laterality, size and shape), the indi cation of the ultrasound scan and the follow-up time were analyzed. Of 147 patients with thyroid nodules, we identified 12 children with lesions suggestive of an IET (8.1%). The mean age at diagnosis was 3.9 years (range 0-8). It was an incidental finding in all cases. Imaging findings were unilateral in eight patients and bilateral in four patients. All lesions were located in the mid and/or posterior portion of the gland. We adopted a watch-and-wait approach with ultrasound follow-up (mean 2.2 years; range 0.83-4) in all patients except in a 7-year-old boy who presented uncertain findings and underwent surgery, confirming IET in the pathological study. Thymic inclu sions in the thyroid gland are a rare but increasingly frequent finding, possibly related to the increased use of ultrasound studies. Pediatricians and radiologists should be aware of this entity to differentiate it from other thyroid lesions, avoiding unnecessary studies and/or treatments in these patients.

КАРЦИНОМА ПАРАЩИТОВИДНОЙ ЖЕЛЕЗЫ С ИНТРАТИРЕОИДНЫМ РАСПОЛОЖЕНИЕМ: СЛУЧАЙ ИЗ ПРАКТИКИ

Carcinoma of the parathyroid gland is a rare malignant tumor of the person, which manifests itself clinical syndrome of hyperparathyroidism. The tumor is characterized by structural signs of invasive growth and is characterized by an unfavorable clinical prognosis, often accompanied by metastasis and the formation of relapses. The article provides background information about the incidence of parathyroid carcinoma, the gender and age characteristics of patients with this disease, options for localization of the tumor in the gland itself (typical topic of the neoplasm), in other areas of the neck, thyroid, thymus, and so on. We discuss the features of clinical manifestations of parathyroid carcinoma, among which the most typical are manifestations of hyperparathyroidism and hypercalcemia, and also provide figures for five - and ten-year survival. The article presents the author’s observation of parathyroid carcinoma with an intrathyroid location in a 64-year-old man. After the examination, the patient underwent a cervicotomy with revision of the areas of the typical location of the parathyroid gland in the neck, hemithiroidectomy on the left with a parathyroid tumor incorporated in the thyroid tissue, which was later proved using immunohistochemical research methods. The article details the macroscopic, microscopic, and immunohistochemical characteristics of the operating material. A special feature of the case is a rare atypical intrathyroid localization of parathyroid carcinoma.

Role of parathyroid hormone measurement in fine-needle aspiration biopsy washout in diagnosis and treatment of primary hyperparathyroidism

In this article, we discuss difficulties in parathyroid localization modalities in diagnosis of primary hyperparathyroidism. Most often, superior parathyroid glands are located on the posteromedial surface of the right and left lobes of the thyroid gland, however, they also could be found at the carotid bifurcation, behind pharynx and esophagus, as well as inside thyroid gland. Location of the inferior parathyroid glands is more variable: on the side or back surface, or below the lower pole of the thyroid gland, as well as in thymus, posterior or anterior mediastinum, or inside thyroid. Localization modalities of primary hyperparathyroidism are based on neck ultrasonography, scintigraphy with sestamibi, computed tomography of neck and mediastinum. In cases with combination of multinodal goitre and an intrathyroid location of the parathyroid gland, there might be additional difficulties in verification of various patterns (thyroid nodules or parathyroid glands). In this article, we present two clinical cases of intrathyroid location of parathyroid glands. The algorithm of parathyroid adenoma localization is shown. Determination of PTH level in washing liquid after fine-needle aspiration biopsy from necessary punctures of the nodule formations, which can be either intrathyroid parathyroid glands or thyroid nodules, can also help to avoid diagnostic mistakes.

Dificulties of perioperative topical diagnostics of primary hyperparathyroidism in case of multiglandular disease and intrathyroid location of parathyroid gland

Dificulties of perioperative topical diagnostics of primary hyperparathyroidism in case of multiglandular disease and intrathyroid location of parathyroid gland

Incidental Parathyroidectomy during Total Thyroidectomy: Risk Factors and Consequences.

Objective. To evaluate the incidence of accidental parathyroidectomy in our series of total thyroidectomies, to investigate its clinical and biochemical consequences, and to identify potential risk factors. Methods. Patients who underwent total thyroidectomy between January 2006 and December 2015 were retrospectively analyzed. Pathology reports were reviewed to identify those cases who had an incidental parathyroidectomy and these were compared to patients with no parathyroidectomy, in terms of clinical (age, sex, and symptoms of hypocalcemia), pathological (thyroid specimen weight, Hashimoto thyroiditis, and malignancy), and biochemical (serum calcium and phosphate levels) factors. Results. 281 patients underwent total thyroidectomy during the study period. Incidental parathyroidectomy was noticed in 24.9% of cases, with 44.3% of parathyroid glands found in an intrathyroidal location. Evidence of postoperative biochemical hypocalcemia was noticed in 28.6% of patients with parathyroidectomy, compared with 13.3% in the no-parathyroidectomy group (p = 0.003). Symptomatic hypocalcemia was observed in 5.7% and 3.8%, respectively (p = 0.49). Age, sex, thyroid specimen weight, Hashimoto thyroiditis, and malignancy did not differ significantly between the two groups. Conclusions. Our study found an association of incidental parathyroidectomy with transient postoperative biochemical hypocalcemia, but not with clinically symptomatic disease. Age, sex, thyroid gland weight, Hashimoto thyroiditis, and malignancy were not identified as risk factors.

High Risk of Lateral Nodal Metastasis in Lateral Solitary Solid Papillary Thyroid Cancer

We explored the relationship between ultrasonic intra-thyroidal location and neck node metastasis pattern in solitary solid papillary thyroid cancer (PTC). Data on 186 patients were retrospectively reviewed. The association between several characteristics and neck node metastasis pattern were analyzed. Among the 186 thyroid nodules, age ≥45 y (p = 0.005), mass size ≥2 cm (p = 0.001), presence of calcifications (p < 0.001) and lateral nodal metastasis (p = 0.001) were significantly related to central nodal metastasis in multivariate analysis. Mass size ≥2 cm (p = 0.046) and central nodal metastasis (p = 0.002) were significantly related to lateral nodal metastasis in multivariate analysis. Location of an intra-thyroidal solitary solid PTC located non-adjacent to the trachea (lateral) was significantly related to lateral nodal metastasis (p = 0.043) compared with location of an intra-thyroidal solitary solid PTC adjacent to the trachea (medial or isthmus). Lateral lesions have a high risk of lateral nodal metastasis in solitary solid PTC.

Incidence of intrathyroid location of parathyroid glands and description of their characteristics compared to extrathyroid ones

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Posterosuperior lesion has a high risk of lateral and central nodal metastasis in solitary papillary thyroid cancer.

Preoperative nodal assessment of papillary thyroid cancer (PTC) is very important because 60 to 70 % of all disease recurrence in the neck can occur in the lymph nodes. This study explored the association between ultrasonographic intrathyroidal location and the nodal metastasis pattern in solitary PTC. Data from 218 patients who underwent total thyroidectomy with or without neck dissection for previously untreated PTC between 2006 and 2010 were retrospectively analyzed. Only patient data for which both preoperative ultrasound findings and postoperative pathologic reports were available were included. Multifocal cases, cases with extrathyroidal extension, and distant metastasis were excluded. The association between nodal metastasis pattern and clinical or pathologic features of solitary PTCs was analyzed, as was the association between ultrasonographic intrathyroidal location and central or lateral nodal metastasis in solitary PTC. Mass size larger than 2 cm (p < 0.001, Odds ratio (OR) 4.117) and central nodal metastasis (p < 0.001, OR 3.984) were related with lateral neck metastasis in multivariate analysis. Male sex (p = 0.001, OR 3.012) and capsular invasion (p < 0.001, OR 4.720) were related with central neck metastasis in multivariate analysis. When analyzing ultrasonographic location of intrathyroidal solitary lesion, posterosuperiorly located lesion was strongly associated with both lateral and central neck metastasis. (p < 0.001 and p = 0.002, respectively). Posterosuperior location of intrathyroidal solitary PTC has a high risk of lateral and central nodal metastasis when compared to other locations. For such patients, careful preoperative evaluation of nodal status should be done.

Imaging diagnostics for primary hyperparathyroidism

Primary hyperparathyroidism (PHP) is a benign condition characterised by malignant potential. Even in specialist wards, 5-10% of operations for PHP are unsuccessful. The main reasons seem to be ectopy of the parathyroid gland, numerous adenomas, multiglandular parathyroid hyperplasia, and intrathyroid location of the parathyroid. The last three decades have witnessed a rapid progression in imaging diagnostics.

An Analysis of Factors Predicting Lateral Cervical Nodal Metastases in Papillary Carcinoma of the Thyroid

To analyze the possible correlation between the location of the primary tumor within the thyroid gland and the patterns of central vs lateral compartment lymph node metastasis. Retrospective analysis of papillary thyroid carcinoma (PTC) treated in an academic university setting from July 1, 2004, through August 31, 2010. Head and neck oncology clinic. Those receiving surgical therapy for PTC at the University of Utah. Tumor characteristics of patients with central vs lateral nodal metastatic disease in PTC. Two hundred one patients with PTC met inclusion criteria. There were 136 females (67.7%), and the mean age was 44.8 years. Histologic subtypes included 68 follicular variants of PTC, 111 conventional variants of PTC, and 22 patients with both follicular and conventional PTC variants. Metastatic nodal disease was confirmed histologically in 81 patients (40.3%): 42 with central nodal disease only (20.9%), 10 with lateral disease only (5.0%), and 29 with both central and lateral nodal disease (14.4%). Positive lateral compartment nodal metastasis correlated with distant metastases (P<.01), extrathyroid extension (P<.05), histologic subtype (conventional PTC greater than follicular variant PTC) (P<.05), and tumor location within the thyroid lobe (P<.01). Tumors involving the superior aspect of the thyroid lobe were more likely to be associated with metastasis to the lateral cervical lymph nodes (P<.01), and 76.9% of patients with lateral cervical lymph node disease had involvement of the superior aspect of the lobe. Thyroid microcarcinomas were not associated with lateral cervical compartments in this study. The intrathyroidal location of PTC predicts the pattern of nodal spread. Therefore, patients with PTC involving the superior aspect of the lobe should undergo specific imaging evaluation of the lateral neck compartments to determine the need for lateral compartment neck dissection.

Incidental parathyroidectomy during thyroid resection: incidence, risk factors, and outcome

BACKGROUND AND OBJECTIVES:Thyroidectomy is a commonly performed procedure for thyroid problems. Inadvertent removal of the parathyroid glands is one of its recognized complications, which occurs more frequently in certain high-risk patients. The aim of this study was to identify the incidence, risk factors, and clinical relevance of incidental parathyroidectomy during thyroid surgery.DESIGN AND SETTING:A retrospective review of thyroid operations performed at a tertiary referral hospital between January 2004 and December 2008.METHODS:Pathology reports were reviewed to identify the specimens that included parathyroid tissue and underlying thyroid pathology. Postoperative calcium levels were reviewed in these patients.RESULTS:During the study period, 287 thyroidectomies were performed and 47 (16.4%) patients had incidentally removed parathyroid glands. Risk factors for inadvertent parathyroid resection included total thyroidectomy (P=.0001), Hashimoto thyroiditis (P=.004), and extrathyroidal spread (P=.0003). Postoperative hypocalcemia occurred in 18 (38.3%) of the patients in whom the parathyroid gland was removed inadvertently and in 48 (20%) of the rest of the patients (P=.0123).CONCLUSION:The incidence of incidental removal of parathyroid tissue during thyroidectomy is 16.4%. Total thyroidectomy, extrathyroidal extension of the tumor, and thyroiditis were found to be the risk factors. Hypocalcemia was significantly higher among patients who had inadvertent parathyroidectomy.

Intrathyroidal oncocytic parathyroid adenoma: A diagnostic pitfall on fine‐needle aspiration

Oncocytic parathyroid adenoma is a rarely seen benign neoplasm of the parathyroid and intrathyroidal location of this lesion is also uncommon. It can be easily misdiagnosed as Hürthle cell thyroid neoplasm on fine-needle aspiration (FNA). Here, an intrathyroidal oncocytic parathyroid adenoma in a 32-year-old male is reported. Ultrasonography showed a nodule 2 cm in largest diameter in the left thyroid lobe. FNA revealed cellular smears containing monotonous oncocytic cells arranged in monolayered sheets, pseudopapillary structures and clusters within a rich vascular network. The case was reported as "suspicious for Hürthle cell thyroid neoplasm" on FNA. Frozen section examination showed intrathyroidal oncocytic parathyroid adenoma with a rim of normal parathyroid tissue. The diagnosis was also confirmed with immunohistochemical stains (TTF-1, PTH, thyroglobulin) performed on permanent sections. Cytopathologic features of oncocytic parathyroid adenoma and Hürthle cell thyroid neoplasm are similar. It is important to keep oncocytic parathyroid adenoma in mind in the differential diagnosis of Hürthle cell thyroid neoplasm. Prior knowledge of clinical, radiological and laboratory data will avoid wrong cytopathologic diagnosis.

Intrathyroidal Thymic Tissue Surrounding an Intrathyroidal Parathyroid Gland, the Cause of a Solitary Thyroid Nodule in a 6-Year-Old Boy

Ectopic intrathyroidal thymic tissue is a rare occurrence; parathyroid glands sometimes occur in an intrathyroidal location, but this is uncommon. We report a 6-year-old boy who was noted to have a solitary thyroid nodule on ultrasound. A hemithyroidectomy was performed, and histological investigation revealed that the nodule consisted of ectopic intrathyroidal thymus tissue surrounding a well-defined parathyroidal gland. This condition is an exceedingly rare cause of a thyroid nodule, but intrathyroidal thymic tissue should probably be included in the differential diagnosis of solitary thyroid nodules.