ONCOCYTIC INTRATHYROID PARATHYROID ADENOMA MASQUERADING AS HURTHLE CELL NEOPLASM: FINE NEEDLE ASPIRATION CYTOLOGY OF TWO CASES

Ectopic parathyroid adenomas in thyroid tissue are uncommon (0.7 - 6%), and their oncocytic variants are exceedingly rare. We report two cases of intrathyroid parathyroid adenoma which were diagnosed as Hurthle cell adenoma on cytology. Case 1 is a 49-year-old female with a 2.4 cm hypoechoic nodule in the left lateral neck. Electrochemiluminescent immunoassay of the aspirate revealed PTH level of 422 pg/ml, conrming the presence of hyperfunctional parathyroid tissue. Subsequent resection of the left thyroid lobe revealed an enlarged intrathyroidal parathyroid. Case 2 is a 58-year-old female with a 2.1 cm hypoechoic nodule in the posterior-mid left thyroid lobe. Strong overexpression of parathyroid hormone and Chromogranin A genes and low expression of thyrocyte-related genes suggested parathyroid origin of the cells sampled. MEN1 mutation and multiple copy number alterations indicated the neoplastic nature of the nodule. Parathyroid oxyphil cells and oncocytic thyrocytes share cytomorphological ndings and distinguishing them by cytology alone is challenging, especially when the targeted lesion is intrathyroidal. Distinguishing intrathyroid oncocytic parathyroid adenoma from oncocytic thyroid follicular lesions has signicant clinical implications as Bethesda-IV category lesions have 20%–30% risk of malignancy. While stippled chromatin or intracytoplasmic fat vacuoles may be suggestive of parathyroid origin, these are not specic. Classifying the origin of a nodule as parathyroid vs thyroid rests upon the detection of PTH in aspirate material by ECL, immunocytochemistry or next-generation sequencing. In parathyroid aspirates, PTH level 100 pg/mL is suggestive of the presence of PTH-secre ≥ ting tissue at the site biopsied or along the needle track.

Thyroid Gland Abscess: Uncommon complication

The thyroid gland is naturally resistant to infectious processes, which explains the rarity of thyroid abscess. It represent about 0.1% of the surgical thyroid pathology. We report in this article a case of thyroid gland abscess in a 61 year-old man who was followed for diabetes and hypothyroidism with poor adherence, who consulted in emergency department for acute neck swelling. CT scan showed a fluid collection of the left thyroid lobe. The patient was operated, and histopathological examination concluded of laryngeal carcinoma associated to thyroid papillary carcinoma.

Unnecessity of Routine Dissection of Right Central Lymph Nodes in cN0 Papillary Thyroid Carcinoma Located at the Left Thyroid Lobe

ObjectiveThe lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) is an important part of the central lymph nodes (LNs). We aimed to explore the rate and predictors of LN-prRLN metastasis in cN0 papillary thyroid carcinoma (PTC) located at the left thyroid lobe.MethodsPatients with surgically treated primary left lobe PTC were retrospectively enrolled. The metastatic distribution of LN-prRLN and postoperative complications were assessed. The association between LN-prRLN metastasis and clinicopathological variables was evaluated by univariate and multivariate analyses.ResultsA total of 857 patients were included for the analysis. Central LN metastasis was noted in 310 (35.3%) cases. The most (27.6%) and least (1.7%) commonly involved LNs were the left paratracheal LN and the LN-prRLN. In the univariate analysis, the tumor size, multifocality, the extent of extrathyroidal extension (none vs. macroscopic vs. macroscopic maximal), and perineural invasion were associated with positive LN-prRLN. In the multivariate analysis, tumor size of >40.0 mm and macroscopic maximal invasion were found as the only two independent predictors. Transient and permanent hypoparathyroidism were noted in 90 (10.2%) and 13 (1.5%) patients, respectively. Voice change was noted in 40 (4.6%) patients, and 20 patients recovered.ConclusionsIn cN0 PTC located at the left lobe, LN-prRLN metastasis was very uncommon. We found that LN-prRLN dissection is not required routinely, but should be performed if the tumor size is >40.0 mm and macroscopic maximal extrathyroidal extension is present.

Thyroid Gland Abscess: Uncommon complication

The thyroid gland is naturally resistant to infectious processes, which explains the rarity of thyroid abscess. It represent about 0.1% of the surgical thyroid pathology. We report in this article a case of thyroid gland abscess in a 61 year-old man who was followed for diabetes and hypothyroidism with poor adherence, who consulted in emergency department for acute neck swelling. CT scan showed a fluid collection of the left thyroid lobe. The patient was operated, and histopathological examination concluded of laryngeal carcinoma associated to thyroid papillary carcinoma.

Non-functioning oxyphilic parathyroid carcinoma: a case report

Background Non-functioning parathyroid carcinoma is an extremely rare malignancy among endocrine tumors. We report a case in which non-functional oxyphilic parathyroid carcinoma was diagnosed from clinical symptoms and pathological diagnosis. Case presentation The patient was a 42-year-old man with no medical or family history of note. He had presented to a local hospital with a neck mass 2 months earlier. Medullary thyroid carcinoma was diagnosed and he was referred to our department. A 3.5-cm mass was observed in the left thyroid lobe. Laboratory data for thyroid functions, thyroglobulin, anti-thyroglobulin antibodies, anti-thyroid peroxidase antibodies, serum calcium, and parathyroid hormone (PTH) were all within normal ranges. Ultrasonography revealed a 40-mm irregular, hypoechoic mass throughout the left thyroid lobe. Follicular thyroid tumor was suspected from fine-needle aspiration cytology. Left lobectomy was performed. Pathological features revealed a thick fibrous capsule around the tumor, and a thick fibrous band was observed inside the tumor. Both capsular invasions and vascular invasions were observed. Tumor cells were eosinophilic and displayed solid growth. Immunohistochemically, tumor cells were negative for thyroid transcription factor-1, negative for thyroglobulin, negative for chromogranin A (positive for normal parathyroid tissue within the nodule), positive for PTH, and positive for parafibromin. Ki-67 labeling index was 10%. Based on these findings, non-functional oxyphilic parathyroid carcinoma was diagnosed. One and a half years postoperatively, calcium and PTH were within normal ranges, and he has shown no evidence of recurrence or metastasis. Conclusions Non-functioning oxyphilic parathyroid carcinoma is an extremely rare malignancy, and definitive diagnosis is difficult to obtain preoperatively. Few reports have been made worldwide, and information on the long-term prognosis is scarce. Long-term surveillance by imaging is mandatory, since no indices that can be used as a marker for postoperative recurrence and metastasis have been identified.

The Unusual Case of a Rapidly Enlarging Thyroid Gland in a Patient With Pendred Syndrome

Pendred syndrome is a genetic condition that is characterized by sensorineural hearing loss, abnormalities of the vestibular system, and goiter. In patients with Pendred syndrome, goiter tends to develop in late childhood or early adulthood and the literature details a progressive enlargement of goiter in these individuals. Here we report the case of a 26 year old female with Pendred syndrome and congenital deafness who presented with a rapidly enlarging thyroid gland over 1 week with associated symptoms of dysphagia, dyspnea, insomnia, and diaphoresis. Thyroid function tests at the time showed no abnormalities. Diagnostic thyroid ultrasound was performed and showed enlarged, multinodular goiter and bilateral thyroid nodules measuring 1.2 cm and 1.1 cm in the right and left thyroid lobe, respectively, with TI-RADS 2 classification. The patient had a thyroid core biopsy performed showing benign appearing thyroid follicles without any evidence of malignancy. After approximately one month following the initial presentation, the patient reported resolution of her goiter and associated symptoms without intervention. To our knowledge, this is the first case in the literature detailing a rapidly enlarging goiter in a patient with Pendred Syndrome, with subsequent resolution of signs and symptoms.

Benign, Malignant or Something in Between: A Rapidly Developing Atypical Parathyroid Adenoma

Introduction: Although Primary Hyperparathyroidism (PHPT) is the third most common endocrine disorder, parathyroid carcinoma and atypical parathyroid adenoma are the rarest of endocrine tumours. The true incidence of atypical parathyroid adenomas has been elusive to endocrinologists since it is not possible to differentiate clinically between parathyroid carcinoma and atypical parathyroid adenomas before histological analysis. Atypical parathyroid adenoma represents a group of an intermediate form of parathyroid neoplasms with uncertain malignant potential. The majority of patients present with hypercalcaemia, however the development of atypical adenoma in patients with known PHPT is extremely rare. Clinical Case: A 78-year-old gentleman presented at the emergency department with lethargy and slurred speech which had started 1 week ago. Blood tests revealed severe hypercalcaemia. (Ca 4.98 mmol/L, PTH 114.2 pmol/L). The patient had a background of primary hyperparathyroidism which was diagnosed due to incidental mild hypercalcaemia (Ca 2.71 mmol/L, PTH 17.57 pmol/L, 25OH-vitamin D3 55 nmol/L). 2 weeks prior to presentation to the Emergency Department calcium and PTH levels were stable. On clinical examination, he was found mildly confused with no other clinical findings. No precipitating factors were identified. Hydration with IV crystalloids commenced and bisphosphonate IV was given. In view of PHPT Cinacalcet was added to treatment (30 mg BD). While the calcium levels seemed to improve initially, (lowest level achieved Ca 3.05 mmol/L) a week later they started to rise gradually. Hypercalcaemia proved refractory to medical treatment despite concomitant use of aggressive hydration, increased cinacalcet dose, second intravenous bisphosphonate, and intravenous calcitonin. Neck U/S revealed a probable parathyroid adenoma measuring 2cm axially at the inferior pole of the left thyroid lobe. In view of the severity and refractory nature of hypercalcaemia, a PET CT was requested which identified an 18 mm soft tissue mass in the left lower neck posterior to the left thyroid lobe with moderate to intense FDG uptake. There was no evidence of increased uptake elsewhere. The patient required 2 sessions of haemodialysis to maintain calcium levels around 3.5 preoperatively. He underwent parathyroidectomy with histological findings in keeping with atypical parathyroid adenoma. Gradual reduction of calcium levels was noted post-operatively with the lowest on day 10 (1.99) when he was started on oral calcium supplementation. The patient remains under follow-up with normal calcium levels 6 months postoperatively while remains on calcium and vitamin D3 supplements. Conclusion: To our knowledge, this is the only case of a patient with known primary hyperparathyroidism and mild hypercalcaemia, to develop severe parathyroid crisis with refractory to medical management hypercalcaemia within 2 weeks. Prompt surgical intervention remains of paramount importance in the management of these patients. They should have lifelong follow up in the view of uncertain malignant potential of the atypical parathyroid adenoma.

Incidental Poorly Differentiated Thyroid Cancer in Trauma Patient

Poorly differentiated carcinomas tend to arise de novo or transform from differentiated thyroid carcinomas. Females, middle-aged and elderly adults are most commonly affected. Patients present with an enlarging thyroid mass which is often locally advanced at presentation. This is a case of 30-year-old male patient admitted after burn injury who presented with neck enlarging mass. He had no family history of thyroid CA, no radiation exposure and normal thyroid function tests. Neck CT imaging found with heterogeneous enhancing mass arising from the left thyroid lobe. Thyroid ultrasound consistent with a large left thyroid lobe lesion described as a complex solid component measures at least 5.2 cm long x 4.0 cm AP by 5.0 cm transverse with coarse scattered echogenic foci, and smaller bright echoes with comet-tail artifacts. Fine needle biopsy was non-diagnostic or unsatisfactory. Second FNA with Atypia of undetermined significance. Left hemithyroidectomy performed consistent with a 5cm Poorly differentiated thyroid carcinoma arising in a preexisting papillary thyroid carcinoma with extensive necrosis, pT3aNx, TTF1 +, PAX 8 +, CK7 +. Right thyroid was negative for malignancy. A Therapeutic dose of 135.7 mCi of 131-iodine was given. Subsequent whole body scan with focal findings in the thyroid bed region is consistent with residual functional thyroid tissue. Follow up with normal thyroglobulin levels and negative thyroglobulin antibodies. Neck ultrasound without abnormal tissue or nodules seen at either thyroid bed. Follow up with 18-F-FDG PET/CT scan abnormal study with avid lymph node in the right side of the neck, Level 3. FNA lymph node, cervical right level 3, 1.1cm, ultrasound guided biopsy negative for metastatic carcinoma. Poorly differentiated thyroid carcinomas present as large thyroid masses. The tumor spreads by local invasion into perithyroidal tissues and by distant metastases. Poorly differentiated carcinoma is supported by immunohistochemical staining for Tg, TTF1, and paired box protein Pax 8 (PAX8). There is no standardized treatment for PDTC to date. If possible, a total thyroidectomy including lymph node dissection should be performed to improve survival rates. Due to the higher rate of ETE, positive margins, neck disease, and distant metastases, adjuvant treatment should be considered. Some experts recommended considering adjuvant RAI in all PDTC patients, giving the potential benefit and lack of morbidity. However, despite the capability of RAI uptake in a high percentage of PDTC, no significant impact on survival has been reported. It is important to recognize prognosis of PDTC is distinctly less favorable than that of PTC or FTC. Several factors have been identified to affect patient prognosis such as extensive tumor necrosis, >45 year of age, tumor size (>5 cm), extrathyroidal extension and distant metastases are unfavorable prognostic factors.

Toxic Thyroid Nodule: To FNA or Not?

Background: ATA guidelines recommend evaluation of hyperthyroidism with radioiodine scan and consideration of FNA for non-toxic nodules with suspicious sonographic features. However, there is no standard evidence-based approach to performing ultrasound in patients with toxic nodules. Recent studies have shown increased rates of thyroid cancer in patients with hyperthyroidism and has been shown to demonstrate aggressive histologic features. Clinical Case: A 41-year-old female presented to primary care provider for annual physical exam, found to have intermittent bigeminy and enlarged thyroid on exam. EKG notable for multiple premature ventricular complexes. Evaluation revealed suppressed TSH <0.01 µIU/mL (0.27-4.20), normal free T4 1.27 ng/dL (0.80-1.80), slightly elevated free T3 4.84 pg/mL (2.57-4.43) and elevated TSI 238% (<122). Methimazole was started for treatment of hyperthyroidism. Thyroid sonogram was ordered for abnormal exam, that showed 2.7 cm TIRADS 4 left thyroid nodule with microcalcifications. I-131 uptake values were 20% and 49% at 4-hours and 24-hours, respectively. Technetium-99M scan showed toxic autonomous nodule in the left thyroid lobe corresponding to the one seen on sonogram. The remainder of the thyroid gland showed heterogeneously suppressed uptake. FNA of the thyroid nodule was done due to the presence of microcalcifications and the cytopathology was suspicious for papillary carcinoma. She underwent total thyroidectomy with central neck dissection involving pre-tracheal and paratracheal lymph nodes (level VI). Pathology showed 1.4 cm papillary carcinoma with lymphovascular space invasion and multifocal papillary microcarcinomas in the left thyroid lobe, 0.2 cm papillary microcarcinoma in right thyroid lobe, metastatic papillary carcinoma in 2 out of 5 lymph nodes, largest metastatic deposit 0.1 cm in the largest dimension with no extra nodal extension. There was also follicular hyperplasia noted consistent with Graves’ disease. Post-operatively, she had thyrogen-stimulated adjuvant RAI treatment, dose 107.4 mCi. Post therapy scan did not show evidence of distant metastases. Conclusion: This case demonstrates the identification of a metastatic papillary thyroid carcinoma based on suspicious ultrasound features requiring total thyroidectomy, central neck dissection and adjunct radioactive iodine in a patient with hyperthyroidism from co-existent toxic thyroid nodule and Graves’ disease.