Thyroid and Parathyroid Surgery MCQs

Surgery · 170 free questions with answers & explanations.

A 35-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma. Six hours postoperatively she develops perioral tingling, carpopedal spasm and a positive Chvostek's sign. Serum calcium is 6.8 mg/dL. What is the most likely cause?
A 50-year-old man presents with a solitary thyroid nodule. Fine-needle aspiration cytology is reported as Bethesda category IV (follicular neoplasm). What is the recommended management?
A patient with primary hyperparathyroidism is found to have a single enlarged parathyroid gland on sestamibi scintigraphy. Intraoperatively, a 1.2 cm adenoma is excised and intraoperative PTH drops by more than 50% within 10 minutes. What does this indicate?
The most common thyroid malignancy in adults is:
A 35-year-old woman undergoes hemithyroidectomy for a 3.5 cm follicular thyroid lesion. Histopathology shows transcapsular and vascular invasion with >4 foci of vascular invasion. According to WHO 2022 classification, this is best categorized as:
Post-total thyroidectomy, a patient develops perioral tingling and positive Chvostek sign on day 1. Calcium is 7.2 mg/dL, phosphate is elevated. Which intraoperative event most likely caused this presentation?
A patient with primary hyperparathyroidism has a sestamibi scan showing a single left lower parathyroid adenoma. Intraoperative PTH monitoring is used. After removal, a 10-minute post-excision PTH level drops from 180 pg/mL to 38 pg/mL (>50% drop, within normal range). The appropriate next step is:
A 55-year-old man is found to have a 1.8 cm right thyroid nodule with BETHESDA category VI cytology (malignant, consistent with papillary thyroid carcinoma). Preoperative ultrasound shows no lymphadenopathy. The most appropriate surgical management is:
A patient with MEN2A syndrome is found to have an RET proto-oncogene mutation in codon 634. Prophylactic thyroidectomy should be performed at what age according to risk-stratified guidelines?
A 52-year-old patient undergoes total thyroidectomy for papillary thyroid carcinoma. On postoperative day 1, she develops perioral numbness and carpopedal spasm. Serum calcium is 6.8 mg/dL. Chvostek's sign is positive. The most likely explanation for this complication and the immediate treatment is:
During parathyroid surgery for primary hyperparathyroidism, four-gland exploration reveals three enlarged glands and one normal-sized gland. Intraoperative PTH drops by only 42% fifteen minutes after removing the three adenomas. The correct interpretation and next step is:
Which variant of papillary thyroid carcinoma has the WORST prognosis with a 10-year disease-specific mortality approaching 65%, and is classified separately in TNM staging?
A 60-year-old man presents with a rapidly enlarging painless neck mass, stridor, and dysphagia over 6 weeks. FNA shows highly pleomorphic cells with giant multinucleated cells and spindle cells. What is the most likely diagnosis and its expected 1-year survival?
In MEN2A syndrome, the order of priority in which the three component tumours should be surgically addressed to prevent life-threatening complications is:
A 35-year-old man undergoes total thyroidectomy for papillary thyroid carcinoma (1.8 cm, N1a, M0). Postoperatively, he develops carpopedal spasm and a positive Chvostek sign. Serum calcium is 7.0 mg/dL. The pathophysiology of the hypocalcemia is most accurately explained by:
A 28-year-old woman has a thyroid nodule (1.2 cm). FNAC shows Bethesda Category V (suspicious for malignancy). Molecular testing shows a BRAF V600E mutation. On staging, no lymphadenopathy is present. The most appropriate initial surgical management per ATA 2015 guidelines is:
A 55-year-old woman with MEN1 syndrome has primary hyperparathyroidism (serum calcium 11.8 mg/dL, PTH 145 pg/mL). Sestamibi scan is negative. The most appropriate surgical strategy differs from sporadic primary hyperparathyroidism because:
A 65-year-old man undergoes left total thyroid lobectomy. Intraoperatively, the surgeon identifies the recurrent laryngeal nerve (RLN) just before the nerve enters the larynx. A small branch of the inferior thyroid artery is noted crossing the nerve from the medial side. The variant nerve relationship described is most associated with:
In the Bethesda System for Reporting Thyroid Cytopathology (BSRTC), a FNA classified as Bethesda Category IV (Follicular Neoplasm) carries which estimated risk of malignancy and recommended management?
A patient with familial hyperparathyroidism is found to have a mutation in the MEN1 gene. What is the recommended surgical strategy for primary hyperparathyroidism in this setting compared to sporadic disease?
Intraoperative neural monitoring (IONM) of the recurrent laryngeal nerve during thyroid surgery is used as a real-time guide. What is the MOST important action when continuous IONM shows a sudden loss of signal (LOS) from the RLN on the first side?
Which of the following best describes the embryological basis of the pyramidal lobe of the thyroid and its clinical relevance during thyroidectomy?
A 35-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma (T2N0M0). Intraoperatively, the recurrent laryngeal nerve (RLN) is identified and preserved. On postoperative day 1, she is found to have a serum calcium of 7.4 mg/dL and complains of perioral numbness. Which statement best describes the pathophysiology of her complication?
A 50-year-old man presents with hypercalcemia (serum calcium 11.8 mg/dL), normal renal function, and a serum PTH of 85 pg/mL (normal: 15-65 pg/mL). A Sestamibi scan localizes to the lower right parathyroid. What is the most appropriate surgical approach?
In medullary thyroid carcinoma (MTC), which tumor marker is most useful for monitoring disease recurrence after total thyroidectomy?
A 28-year-old man is referred with a germline RET mutation (C634F in exon 11) identified on screening. He has no clinical symptoms and a normal neck ultrasound. According to current ATA risk stratification, what is the recommended timing of prophylactic thyroidectomy?
A 40-year-old woman undergoes total thyroidectomy for a 1.5 cm papillary thyroid carcinoma (classical variant, unifocal, intrathyroidal, node-negative). Post-operatively, she develops perioral tingling and Chvostek's sign on day 2. Which intraoperative parathyroid gland injury mechanism best explains transient hypocalcaemia in this scenario?
The RET/PTC rearrangement in papillary thyroid carcinoma activates which signalling pathway, and is particularly associated with which epidemiological trigger?
A 55-year-old man presents with hypercalcaemia (serum calcium 2.9 mmol/L), elevated intact PTH, and a low 24-hour urinary calcium. DEXA scan shows osteoporosis of the lumbar spine. He meets surgical criteria for parathyroidectomy. Which imaging modality is the first-line for pre-operative parathyroid localisation?
According to the ATA 2015 guidelines risk stratification, a patient with multifocal papillary thyroid microcarcinoma (each focus <1 cm) with minor extrathyroidal extension is classified as:
A 35-year-old woman with medullary thyroid carcinoma undergoes total thyroidectomy. Genetic testing reveals a RET proto-oncogene mutation at codon 634 (C634F). Which hereditary syndrome is she most likely to carry?
Intraoperative PTH monitoring (Miami criterion) is used to confirm successful parathyroid adenoma excision. The Miami criterion states the operation is successful when intact PTH falls by:
A patient undergoes bilateral neck exploration for primary hyperparathyroidism. All four glands appear hypercellular and enlarged. Pathology confirms four-gland hyperplasia. The correct surgical management according to current guidelines is:
The AMES scoring system for differentiated thyroid cancer risk stratification incorporates which parameters?
The ESTIMABL2 trial evaluated low-dose versus standard-dose radioactive iodine (RAI) ablation after thyroidectomy for low-risk differentiated thyroid cancer. What was its main conclusion?
A patient with MEN2A is found to have a 4 mm medullary thyroid carcinoma (MTC) on prophylactic thyroidectomy. The pentagastrin-stimulated calcitonin was mildly elevated. Intraoperative examination reveals no gross nodal disease. What is the minimum surgical procedure required according to current guidelines?
During parathyroidectomy for primary hyperparathyroidism, intraoperative PTH monitoring (Miami criterion) is used. The PTH level is measured at baseline and 10 minutes after excision of the presumed adenoma. Which result indicates a successful resection?
A patient undergoes total thyroidectomy for a large multinodular goitre. On post-operative day 1, she develops perioral tingling, carpopedal spasm, and a positive Trousseau sign. Corrected serum calcium is 6.8 mg/dL. What is the mechanism of parathyroid insufficiency MOST likely in this setting?
A 38-year-old woman has a 2.2 cm right thyroid nodule with BRAF V600E mutation on molecular testing after an indeterminate FNA (Bethesda IV category). She also has a 0.6 cm right central compartment lymph node on ultrasound. According to ATA 2015 guidelines, which is the most appropriate initial surgical management?
A patient undergoes parathyroid surgery for primary hyperparathyroidism. Intraoperatively, after removal of an apparent adenoma, intact PTH drops by 65% at 10 minutes (from 145 pg/mL to 50 pg/mL). The Miami criterion for cure is met. However, postoperatively, serum calcium drops to 6.8 mg/dL and PTH is 8 pg/mL at 24 hours. What is the most likely diagnosis?
A 65-year-old man with MEN2A syndrome has a 1.8 cm medullary thyroid carcinoma with elevated basal calcitonin (840 pg/mL). Preoperative imaging shows no distant metastasis. Which of the following is the most critical preoperative evaluation before thyroidectomy?
Intraoperative neuromonitoring (IONM) is used during thyroid surgery. Electromyographic signal is lost in the right recurrent laryngeal nerve (RLN) during dissection of the right lobe. The left lobe has not yet been resected. According to the International Neural Monitoring Study Group guidelines, what is the recommended action?
A patient undergoes hemithyroidectomy for a 2.5 cm follicular thyroid carcinoma. Histology shows capsular invasion only (no vascular invasion). According to current ATA 2015 guidelines risk stratification, this tumor is classified as:
A 55-year-old man with MEN2A undergoes prophylactic total thyroidectomy. Genetic testing shows RET codon 634 mutation (exon 11). According to ATA risk categories for hereditary MTC, this mutation is classified as:
A patient undergoing total thyroidectomy for Graves' disease develops acute hypocalcemia 6 hours postoperatively. Serum PTH level is 8 pg/mL (normal 10-65). The most appropriate initial management is:
In primary hyperparathyroidism caused by a single parathyroid adenoma, the 4D-CT scan is used for preoperative localization. The '4D' in 4D-CT refers to:
A 30-year-old woman undergoes hemithyroidectomy for a 2.8 cm follicular thyroid carcinoma with minimal capsular invasion and no vascular invasion. Postoperative staging: T2N0M0 well-differentiated follicular carcinoma. According to current ATA (American Thyroid Association) 2015 guidelines, she is classified as:
Intraoperative parathyroid hormone (ioPTH) monitoring during parathyroidectomy for primary hyperparathyroidism follows the 'Miami criterion'. A patient's pre-incision PTH is 180 pg/mL; 10 minutes after excision of the presumed adenoma, the PTH drops to 60 pg/mL. What is the correct interpretation and action?
A patient with MEN2A syndrome (RET mutation codon 634) has serum calcitonin of 450 pg/mL and a 1.5 cm thyroid nodule. Preoperative imaging shows no cervical lymphadenopathy. The most appropriate surgical management is:
During total thyroidectomy for a large multinodular goiter, the recurrent laryngeal nerve (RLN) is identified in the tracheoesophageal groove. The surgeon encounters a non-recurrent laryngeal nerve on the right side. What vascular anomaly is characteristically associated with a non-recurrent right laryngeal nerve?
A 45-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma (3 cm, unilateral). Postoperatively she develops tingling in the fingers and toes, positive Chvostek and Trousseau signs. Serum calcium is 7.1 mg/dL and iPTH is <5 pg/mL. The most appropriate first-line management is:
In the Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), a follicular neoplasm reported as Bethesda Category IV carries a malignancy risk of approximately:
A 60-year-old man is found to have serum calcium of 11.8 mg/dL, iPTH 145 pg/mL, and a 24-hour urinary calcium of 380 mg/day. DEXA scan shows T-score of -2.8 at the lumbar spine. He is asymptomatic. According to current guidelines (2014 Fourth International Workshop), indications for parathyroidectomy in primary hyperparathyroidism include all of the following EXCEPT:
Which pre-operative imaging modality has the highest sensitivity and specificity for localizing a single parathyroid adenoma in primary hyperparathyroidism, facilitating a minimally invasive parathyroidectomy (MIP)?
A 35-year-old woman with Graves' disease fails antithyroid drugs after 18 months. She has a large diffuse goiter compressing the trachea and active severe ophthalmopathy. Which management is most appropriate?
During a right hemithyroidectomy, the surgeon identifies the right external laryngeal nerve (EBSLN). Which structure is at risk if the nerve is not identified during ligation of the superior thyroid vessels?
A 48-year-old man is found to have primary hyperparathyroidism with serum calcium 2.9 mmol/L, PTH 120 pg/mL, and a DEXA T-score of -2.7 at the lumbar spine. 24-hour urine calcium is 580 mg. Preoperative sestamibi scan shows a solitary right inferior adenoma. What is the indication for surgery in this patient?
A patient undergoing total thyroidectomy for papillary thyroid carcinoma develops bilateral vocal cord paralysis immediately after extubation. What is the immediate life-saving maneuver?
A patient with a 2.5 cm papillary thyroid microcarcinoma (actually >1 cm, classified T1b) undergoes total thyroidectomy. Post-operatively, serum PTH drawn at 6 hours is 8 pg/mL (normal 15–65). What is the most likely complication and anticipated clinical course?
A 38-year-old patient with MEN1 syndrome is found to have hypercalcemia (calcium 11.8 mg/dL), PTH 180 pg/mL, and 4-gland hyperplasia on sestaMIBI scan. What is the surgical strategy of choice for MEN1-associated primary hyperparathyroidism?
Intraoperative neuromonitoring (IONM) during thyroidectomy shows a drop in signal amplitude of the recurrent laryngeal nerve (RLN) by >50% after the first lobe is removed. According to international guidelines (INMSG), what is the recommended next step?
A 55-year-old patient undergoes parathyroidectomy for primary hyperparathyroidism. Pre-operative sestamibi and 4D-CT localize a single right inferior parathyroid adenoma. Intra-operative PTH falls from 185 to 48 pg/mL at 10 minutes post-excision. By the Miami criterion, is the operation successful?
A 35-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma (PTC). Post-operatively she develops hoarseness. Flexible laryngoscopy reveals left vocal cord paralysis in the paramedian position. This injury most likely results from damage to:
A 50-year-old man with a 2 cm solitary parathyroid adenoma confirmed on sestamibi SPECT-CT undergoes minimally invasive parathyroidectomy. Intraoperative PTH (ioPTH) is measured. Which criterion (Miami criterion) confirms adequate resection?
A 28-year-old woman undergoes surgery for a 3 cm papillary thyroid microcarcinoma variant with extensive extrathyroidal extension and bilateral central neck nodes. Post-operatively, the most appropriate radioiodine ablation strategy involves which TSH stimulation method and target remnant ablation dose?
A patient with MEN 2A syndrome is found to have a RET mutation at codon 634. According to the American Thyroid Association (ATA) risk category for prophylactic thyroidectomy, when should surgery be performed?
A 35-year-old patient with MEN2A syndrome and serum calcitonin 420 pg/mL undergoes total thyroidectomy for medullary thyroid carcinoma (MTC). Intraoperatively, which specific regional lymphadenectomy should be performed as standard of care?
Intraoperative PTH monitoring during parathyroidectomy for primary hyperparathyroidism: what is the Miami criterion for predicting cure?
A 28-year-old woman with MEN1 presents with primary hyperparathyroidism. She is found to have multiglandular hyperplasia on imaging. Which surgical approach provides the best balance of cure and preservation of parathyroid function?
Fick's principle-based localization of sporadic primary hyperparathyroidism most commonly involves which imaging modality combination prior to minimally invasive parathyroidectomy?
A 45-year-old patient undergoes total thyroidectomy for papillary thyroid carcinoma. Post-operatively she develops perioral tingling, positive Chvostek's sign, and albumin-corrected calcium of 7.2 mg/dL. The most common underlying mechanism of this complication is:
Intraoperative neuromonitoring (IONM) of the recurrent laryngeal nerve during thyroid surgery: which signal loss pattern mandates halting ipsilateral dissection immediately?
In primary hyperparathyroidism, the operative cure rate of minimally invasive parathyroidectomy (MIP) guided by preoperative Sestamibi scan is highest when which additional intraoperative tool confirms adequate resection?
A 35-year-old man is found to have a 2.2 cm papillary thyroid microcarcinoma (PTMC) with bilateral multifocal disease. BRAF V600E mutation is confirmed on molecular testing. According to current ATA risk stratification, this patient is classified as:
A patient with primary hyperparathyroidism has a sestamibi scan showing a solitary adenoma in the right inferior position. She undergoes minimally invasive parathyroidectomy. Which intraoperative criterion confirms successful removal of the hyperfunctioning gland?
In the ATA risk stratification for differentiated thyroid cancer, a 2.5 cm papillary thyroid carcinoma with microscopic extrathyroidal extension but no vascular invasion, no lymph node metastases, and no distant metastases falls into which ATA recurrence risk category?
Medullary thyroid carcinoma (MTC) arises from parafollicular C cells. What is the most sensitive marker for monitoring disease recurrence after total thyroidectomy for MTC?
During total thyroidectomy for a large goiter, which anatomical relationship of the recurrent laryngeal nerve (RLN) to the inferior thyroid artery is most commonly found at the level of Berry's ligament?
A 42-year-old woman undergoes total thyroidectomy for multinodular goitre. On postoperative day 1 she develops circumoral tingling, carpopedal spasm, and a positive Trousseau's sign. Serum corrected calcium is 7.2 mg/dL. The most immediate management is:
A 58-year-old man with MEN1 syndrome has biochemically proven primary hyperparathyroidism with four-gland disease confirmed on sestamibi scan. He has had two previous neck operations. The preferred surgical approach for this scenario is:
A thyroid nodule FNA cytology is reported as Bethesda Category IV (follicular neoplasm). The risk of malignancy for this category is:
During thyroidectomy the surgeon identifies the recurrent laryngeal nerve running anterior to the inferior thyroid artery, just lateral to Berry's ligament. Which anatomical variant is this, and what is its clinical significance?
A 34-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma (PTC). Intraoperative nerve monitoring (IONM) shows loss of signal in the right recurrent laryngeal nerve at the end of resection. She is extubated and found to have a normal voice. What is the most appropriate immediate next management step?
Minimally invasive parathyroidectomy (MIP) for primary hyperparathyroidism is guided by pre-operative localisation and intraoperative PTH assay. According to the Miami criterion for intraoperative PTH monitoring, the operation is considered a success when:
A 28-year-old man is found to have elevated calcitonin (320 pg/mL) on routine screening. Fine needle aspiration of a 1.2 cm thyroid nodule reveals medullary thyroid carcinoma (MTC). Genetic testing confirms RET proto-oncogene mutation in codon 634. Which of the following is the MOST appropriate surgical approach?
In the Bethesda System for Reporting Thyroid Cytopathology (BSRTC), a nodule categorised as Bethesda Category IV (Follicular Neoplasm/Suspicious for Follicular Neoplasm) carries an estimated risk of malignancy of approximately:
A 55-year-old woman with a 4 cm papillary thyroid carcinoma and no lymph node involvement (T3aN0M0) undergoes total thyroidectomy. She is found to have a germline RET mutation consistent with familial non-medullary thyroid carcinoma. Post-thyroidectomy, which radioactive iodine (RAI) adjuvant therapy approach is recommended by current ATA guidelines for intermediate-risk PTC?
Multiple endocrine neoplasia type 2B (MEN2B) is associated with the highest-risk RET mutation. Prophylactic thyroidectomy in MEN2B should be performed:
Intraoperative PTH monitoring (Miami criterion) is used during parathyroidectomy for primary hyperparathyroidism. A patient has a pre-incision PTH of 180 pg/mL. After removal of a suspected adenoma, the 10-minute post-excision PTH is 48 pg/mL. This represents a fall of approximately 73% into the normal range. The Miami criterion is:
Which of the following correctly characterises the Delphian node and its significance during thyroid surgery?
During total thyroidectomy for Graves' disease, the surgeon intentionally ligates the inferior thyroid artery medially (close to the gland) to preserve parathyroid vascularity. Which vascular anastomotic relationship makes this manoeuvre protective?
A 55-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma. On postoperative day 1, she develops perioral tingling and Chvostek's sign. Her corrected serum calcium is 6.8 mg/dL. What is the most likely cause?
A patient with primary hyperparathyroidism is found to have a single adenoma on sestamibi scan. Pre-operative PTH is 145 pg/mL. After surgical removal of the adenoma, intraoperative PTH measured at 10 minutes falls to 38 pg/mL. According to the Miami criterion, what should the surgeon do?
A 40-year-old man presents with recurrent renal calculi, peptic ulceration, and a pituitary prolactinoma. Genetic testing reveals a MEN1 mutation. His serum calcium is 11.5 mg/dL. What is the recommended surgical approach for his primary hyperparathyroidism?
During a left hemithyroidectomy, the surgeon identifies the recurrent laryngeal nerve (RLN) entering the larynx posterior to the cricothyroid joint. Which of the following accurately describes the relationship of the RLN to the inferior thyroid artery at this point?
A 35-year-old woman presents with a thyroid nodule. FNA cytology is reported as Bethesda Category IV (follicular neoplasm/suspicious for follicular neoplasm). What is the recommended next step?
A 28-year-old man undergoes prophylactic thyroidectomy after genetic testing confirms a RET proto-oncogene mutation (codon 634, exon 11). His serum calcitonin is normal and no pheochromocytoma has been identified. What syndrome does he have, and at what age should prophylactic thyroidectomy ideally be performed?
A 40-year-old woman undergoes total thyroidectomy. On the second postoperative day, she develops perioral tingling and carpo-pedal spasm. Serum calcium is 6.8 mg/dL. Which of the following indicates permanent hypoparathyroidism rather than transient hypocalcemia?
A 55-year-old man with MEN2A is found to have medullary thyroid carcinoma on calcitonin screening. Surgery is planned. What is the CORRECT sequence of management?
A patient with primary hyperparathyroidism undergoes parathyroid exploration. The surgeon cannot find the adenoma in the expected locations. Which embryological basis explains the most common ectopic site for a SUPERIOR parathyroid gland adenoma?
The BAETS (British Association of Endocrine and Thyroid Surgeons) audit data show that the risk of permanent recurrent laryngeal nerve palsy following total thyroidectomy performed by a high-volume surgeon (>100 cases/year) is approximately:
A patient undergoes hemi-thyroidectomy for a 2 cm follicular neoplasm. Final histology shows a 2.2 cm minimally invasive follicular thyroid carcinoma with capsular invasion only (no vascular invasion). According to ATA 2015 guidelines, the recommended management is:
In sporadic primary hyperparathyroidism, the single most common cause of failed initial parathyroid surgery (persistent or recurrent hypercalcemia) is:
Zuckerkandl's tubercle is a posterior projection of thyroid tissue that is clinically important because:
A 40-year-old man undergoes hemithyroidectomy for a 2.5 cm follicular thyroid carcinoma. Final pathology confirms capsular invasion only (no vascular invasion, no extrathyroidal extension). According to ATA 2015 guidelines, what is the most appropriate next step?
A 30-year-old woman presents with a thyroid nodule. Fine-needle aspiration cytology (FNAC) is reported as Bethesda Category V (suspicious for malignancy). Which molecular marker testing, if positive, would most strongly indicate papillary thyroid carcinoma and guide surgical planning?
During parathyroid exploration for primary hyperparathyroidism, intraoperative PTH (ioPTH) is measured. A 50% drop in PTH from the highest pre-excision level at 10 minutes post-excision is called:
A 28-year-old male with MEN2A undergoes prophylactic total thyroidectomy for a RET codon 634 mutation. When should prophylactic thyroidectomy ideally have been performed based on ATA risk category for this specific mutation?
A 38-year-old woman undergoes total thyroidectomy for a 2.5 cm papillary thyroid carcinoma with a single cervical lymph node metastasis (N1a, no extrathyroidal extension). According to ATA 2015 guidelines, her risk stratification is:
The RET proto-oncogene mutation associated with the highest risk of early aggressive medullary thyroid carcinoma, necessitating prophylactic thyroidectomy within the first 6 months of life, belongs to which MEN2 variant?
During parathyroid exploration for primary hyperparathyroidism, the surgeon uses intraoperative PTH monitoring (Miami criterion). A 50% decline in PTH is measured from the pre-excision level at 10 minutes post-excision, with the post-excision value being 32 pg/mL. The result is interpreted as:
A thyroid nodule with Bethesda category IV (follicular neoplasm/suspicious for follicular neoplasm) cytology on FNA: the most appropriate next step is:
A 38-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma. Post-operatively she develops perioral numbness, tingling of fingertips, and positive Chvostek's sign on day 1. Serum calcium is 7.2 mg/dL (corrected). The MOST likely cause is:
A 55-year-old man with MEN2A syndrome is found to have a 1.2 cm medullary thyroid carcinoma on neck ultrasound. Basal serum calcitonin is 320 pg/mL. Prior to thyroid surgery, the FIRST investigation/intervention that must be performed is:
Which of the following is the MOST important anatomical landmark to identify during thyroidectomy to prevent inadvertent injury to the external branch of the superior laryngeal nerve (EBSLN)?
A 42-year-old woman is found to have asymptomatic primary hyperparathyroidism with serum calcium of 10.9 mg/dL (corrected), PTH 110 pg/mL (normal 15–65), urine calcium 350 mg/24h, and T-score −2.3 at lumbar spine. Her eGFR is 72 mL/min. According to the 2022 international guidelines, this patient:
A 35-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma (PTC). On post-operative day 1, she develops perioral tingling and positive Chvostek's sign. Her serum calcium is 7.2 mg/dL (normal 8.5–10.5 mg/dL). What is the most likely cause of her symptoms?
The ATA (American Thyroid Association) 2015 guidelines classify differentiated thyroid cancer into risk categories for recurrence. Which feature places a patient in the HIGH risk category for recurrence?
In MEN2A syndrome, medullary thyroid carcinoma (MTC) is associated with RET proto-oncogene mutations. Prophylactic thyroidectomy timing depends on the codon mutation category. In codon 634 mutation (ATA risk category C), what is the recommended timing for prophylactic thyroidectomy?
A 62-year-old man with MEN1 syndrome has a serum calcium of 11.8 mg/dL, PTH of 180 pg/mL (normal 15–65), and imaging showing four-gland hyperplasia. What is the most appropriate surgical strategy?
A 35-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma. On post-operative day 1 she develops perioral tingling and a positive Chvostek's sign. Serum calcium is 7.2 mg/dL. What is the most appropriate immediate management?
The Bethesda System for Reporting Thyroid Cytopathology classifies FNA results into six categories. A Category IV (follicular neoplasm/suspicious for follicular neoplasm) result carries an approximate malignancy risk of:
A 55-year-old man with MEN2A syndrome undergoes prophylactic thyroidectomy. Which additional biochemical screening is MOST critical before operating to prevent perioperative crisis?
A 42-year-old patient undergoes total thyroidectomy for papillary thyroid carcinoma. On day 1 post-operatively, serum calcium is 7.2 mg/dL with tingling in the fingertips. Chvostek's sign is positive. The most likely cause is:
A 50-year-old woman is found to have MEN2A syndrome. Genetic testing reveals a RET proto-oncogene mutation at codon 634. Which prophylactic surgery schedule is recommended per ATA guidelines?
A 58-year-old man with recurrent laryngeal nerve palsy on the left side is found to have a 4 cm thyroid mass. Fine-needle aspiration cytology shows Bethesda category VI (malignant) consistent with anaplastic carcinoma. The most appropriate initial management is:
A 45-year-old woman is incidentally found to have a serum calcium of 11.2 mg/dL on routine testing. PTH is 95 pg/mL (elevated). She is asymptomatic with eGFR of 68 mL/min/1.73m² and DEXA T-score of −1.8 at the lumbar spine. Which criterion for parathyroidectomy is met?
A 35-year-old woman has a 1.8 cm solitary thyroid nodule. FNAC shows Bethesda Category IV (follicular neoplasm). Molecular testing reveals a RAS point mutation. The most appropriate next step is:
A patient with MEN2A syndrome undergoes total thyroidectomy for medullary thyroid carcinoma. Intraoperatively, the parathyroid glands appear enlarged bilaterally. The appropriate surgical management of the parathyroids in this setting is:
Regarding the BRAF V600E mutation in papillary thyroid carcinoma, which statement is MOST accurate?
A 48-year-old patient is found to have a serum calcium of 10.9 mg/dL and PTH of 98 pg/mL (normal 15–65). A 99mTc-sestamibi scan shows a single focus of increased uptake at the lower pole of the right thyroid lobe. Intraoperative PTH monitoring is performed. If PTH drops by more than 50% from the pre-excision value to below the upper limit of normal within 10 minutes of gland removal, what does this indicate?
A 28-year-old man is diagnosed with MEN2B syndrome. He has mucosal neuromas, marfanoid habitus, and medullary thyroid carcinoma on genetic screening. His RET mutation is at codon 918 (M918T). According to ATA 2015 guidelines, this mutation places him in which risk category for medullary thyroid cancer aggressiveness?
A 55-year-old woman is found incidentally to have asymptomatic primary hyperparathyroidism: calcium 10.8 mg/dL, PTH 95 pg/mL, creatinine normal, DXA shows T-score -2.3 at lumbar spine. She is otherwise well. According to the 4th International Workshop guidelines (2014), she meets an indication for parathyroidectomy because:
A 55-year-old patient undergoes total thyroidectomy for a 3 cm follicular thyroid carcinoma. On histology, there is capsular invasion with 2 foci of vascular invasion. According to the 2022 WHO classification and ATA guidelines, this tumour is best classified as:
During a completion thyroidectomy, the recurrent laryngeal nerve (RLN) is inadvertently transected on the left side. The patient complains of breathlessness at rest 48 hours post-operatively. Flexible laryngoscopy shows bilateral vocal cord paralysis. What is the most likely explanation?
A 30-year-old woman is found to have a serum calcium of 2.95 mmol/L, PTH of 120 pg/mL (normal 10-65), and 24-hour urine calcium of 60 mg/day. She is asymptomatic and her DEXA scan is normal. The most likely diagnosis is:
A 40-year-old man with MEN2A undergoes prophylactic thyroidectomy. His RET mutation is identified at codon 634 (C634F). At what age should prophylactic thyroidectomy have been recommended according to current ATA guidelines?
A 55-year-old woman has a serum calcium of 2.82 mmol/L, PTH of 95 pg/mL (normal 15–65), 24-hour urine calcium of 2.8 mmol, and DEXA showing osteoporosis (T-score –2.7 at hip). She is asymptomatic. According to current guidelines, the next step is:
During total thyroidectomy, the inferior thyroid artery is ligated medially close to the thyroid gland rather than at its origin to protect which structure?
A patient with MEN 2A syndrome is found to have a serum calcitonin of 450 pg/mL (normal <10) and a 2.5 cm right thyroid nodule on ultrasound. RET codon 634 mutation is confirmed. Which operation is indicated?
Chvostek's sign and Trousseau's sign both appear in a patient on post-operative day 1 after total thyroidectomy. Serum corrected calcium is 1.85 mmol/L. The first-line acute management is:
The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) classifies FNA results into 6 categories. A Bethesda Category IV (Follicular Neoplasm/Suspicious for Follicular Neoplasm) carries an estimated risk of malignancy of approximately:
A patient is planned for re-do parathyroid surgery for persistent primary hyperparathyroidism after failed neck exploration. The most sensitive localisation modality for ectopic or supernumerary parathyroid adenoma prior to re-operation is:
In primary hyperparathyroidism surgery, the Miami criterion for intraoperative PTH monitoring defines successful gland removal as what percentage drop in PTH from the highest pre-excision value at what time point?
The Bethesda System for Reporting Thyroid Cytopathology (BSRTC) classifies a follicular lesion of undetermined significance as Category III, carrying an estimated malignancy risk in the surgical excision population of approximately what percentage?
A 45-year-old undergoes total thyroidectomy for papillary thyroid cancer. On postoperative day 2, serum calcium is 7.1 mg/dL with perioral tingling. Chvostek sign is positive. Serum PTH returns at 4 pg/mL (normal 10–65). Which management is most appropriate?
Which feature most reliably distinguishes papillary thyroid microcarcinoma (PTMC) with low surgical risk from PTMC requiring completion thyroidectomy on active surveillance protocols?
Multiple Endocrine Neoplasia type 2A (MEN 2A) is characterized by medullary thyroid cancer, pheochromocytoma, and primary hyperparathyroidism, all caused by germline mutations in which gene?
The ATA (American Thyroid Association) risk classification for differentiated thyroid cancer categorizes a patient with a 2 cm papillary thyroid cancer, no extrathyroidal extension, R0 resection, no lymph node metastases, and no adverse histological features as which risk category?
A patient undergoing total thyroidectomy develops hoarseness on the first postoperative day. Laryngoscopy shows a paralysed right vocal cord in the paramedian position. Which nerve and which branch was most likely injured?
The Cernea classification grades the relationship between the external branch of the superior laryngeal nerve (EBSLN) and the superior thyroid vessels. In Type 2b, the nerve crosses the superior thyroid vessels:
In primary hyperparathyroidism due to a single adenoma, which intraoperative strategy has been validated to confirm adequate resection and predict operative success?
A 35-year-old man is found to have MEN1 syndrome with primary hyperparathyroidism involving all four glands. The preferred surgical approach is:
Intraoperative nerve monitoring (IONM) is used during thyroidectomy. The recurrent laryngeal nerve (RLN) is most at risk during thyroidectomy at which anatomical location?
A 45-year-old woman with familial hypocalciuric hypercalcaemia (FHH) is referred for consideration of parathyroidectomy. Why is parathyroidectomy NOT indicated in FHH?
The Bethesda System for Reporting Thyroid Cytopathology classifies FNA results into 6 categories. A Bethesda III (Atypia of Undetermined Significance/Follicular Lesion of Undetermined Significance — AUS/FLUS) carries an approximate risk of malignancy of:
Medullary thyroid carcinoma (MTC) secretes calcitonin as a tumour marker. In the RET proto-oncogene mutation landscape, which codon mutation is associated with the most aggressive MTC and mandates prophylactic thyroidectomy in the first 6 months of life?
A 65-year-old woman has persistently elevated serum calcium (3.1 mmol/L) and PTH 120 pg/mL (elevated). Sestamibi SPECT scan is negative. 4D-CT localization also fails to identify a single adenoma. What is the most appropriate surgical strategy?
Anaplastic thyroid carcinoma (ATC) is the most aggressive thyroid malignancy with a median survival of approximately 5 months. The recent molecular driver leading to targeted therapy approval in ATC is:
Superior laryngeal nerve (SLN) injury during thyroidectomy results in which clinical consequence?
Medullary thyroid carcinoma (MTC) arises from parafollicular C cells. Which genetic mutation, when found on somatic testing of an apparently sporadic MTC, should trigger germline RET testing of the patient and family?
In parathyroid carcinoma, which is the most reliable intraoperative feature distinguishing it from a parathyroid adenoma?
A 35-year-old woman with Graves' disease is being prepared for thyroidectomy. She is currently on carbimazole. Which preoperative preparation is SPECIFICALLY given to reduce vascularity of the thyroid gland and reduce intraoperative bleeding?
A 50-year-old man with asymptomatic primary hyperparathyroidism is under observation. Which of the following is an indication for surgical intervention per international guidelines?
Intraoperative neuromonitoring (IONM) is being used during a right thyroid lobectomy. The signal loss in the right recurrent laryngeal nerve (RLN) is detected after division of the superior thyroid vessels but before manipulating the thyroid lobe. What is the most appropriate next step?
A 30-year-old woman has a Bethesda Category IV thyroid nodule (follicular neoplasm) on FNA cytology. Molecular testing using the Afirma Gene Sequence Classifier (GSC) shows a 'suspicious' result. Next management is:
A 35-year-old woman with MTC (medullary thyroid carcinoma) has a RET proto-oncogene mutation at codon 634. Her 6-year-old daughter is tested and found to carry the same mutation but is currently asymptomatic. According to ATA risk stratification (MEN2A codon 634 = ATA High Risk), at what age should prophylactic thyroidectomy be offered?
Post-total thyroidectomy, the patient's parathyroids were inadvertently removed and confirmed on pathology. Sestamibi scan is not applicable. What is the correct long-term management of permanent hypoparathyroidism?
A 65-year-old man with a GIST (gastrointestinal stromal tumor) of the stomach, 8 cm, is resected. Immunohistochemistry confirms CD117 (c-KIT) positive, CD34 positive, DOG1 positive. Mitotic count is 12/50 HPF. This tumor is classified as:
A 55-year-old man with a Type III hiatal hernia (paraesophageal hernia) presents with postprandial chest pain and early satiety. What anatomical feature distinguishes a Type III from a Type II paraesophageal hernia?

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