Endocrine Surgery — MCQs

Endocrine Surgery Indian Medical PG Practice Questions and MCQs

Question 41: A middle-aged female presented with a solitary thyroid nodule of size 2 cm. What is the next line of management?

A. Removal of the nodule
B. Fine Needle Aspiration Cytology (FNAC) (Correct Answer)
C. Subtotal thyroidectomy
D. Total thyroidectomy

Explanation: **Explanation:** The management of a solitary thyroid nodule (STN) follows a standardized diagnostic algorithm. In a clinically euthyroid patient with a palpable nodule, the **initial investigation of choice is Fine Needle Aspiration Cytology (FNAC)**. **Why FNAC is the Correct Answer:** FNAC is the gold standard for the initial evaluation of thyroid nodules because it is minimally invasive, cost-effective, and has high sensitivity and specificity (approx. 95%) for distinguishing between benign and malignant lesions. The results of the FNAC (categorized by the **Bethesda System**) dictate the subsequent surgical or medical management. **Why Other Options are Incorrect:** * **A. Removal of the nodule:** Simple "nodulectomy" is no longer a standard surgical practice for thyroid lesions due to the risk of recurrence and potential for incomplete clearance of malignancy. * **C & D. Subtotal/Total Thyroidectomy:** Surgery is a **therapeutic** step, not a diagnostic one. Performing a major resection without a tissue diagnosis (FNAC) or radiological assessment (USG) violates the standard of care, as many nodules are benign and do not require surgery. **High-Yield Clinical Pearls for NEET-PG:** * **Best Initial Test:** TSH levels. If TSH is suppressed, the next step is a Radionuclide (Iodine-131) scan to look for a "hot" nodule. * **Investigation of Choice (IOC):** FNAC (if TSH is normal or high). * **Most Accurate Test:** Histopathology (post-surgery). * **Bethesda Category I:** Non-diagnostic; requires a repeat FNAC under USG guidance. * **Limitation of FNAC:** It cannot distinguish between **Follicular Adenoma and Follicular Carcinoma**, as this requires evidence of capsular or vascular invasion seen only on histopathology.

Question 42: What is the most dangerous complication in a patient who has undergone thyroid surgery and develops a hematoma at the operative site?

A. Respiratory obstruction (Correct Answer)
B. Recurrent laryngeal nerve palsy
C. Dysphagia
D. Shock

Explanation: **Explanation:** **1. Why Respiratory Obstruction is Correct:** Post-thyroidectomy hematoma is a surgical emergency. The most dangerous complication is **respiratory obstruction (airway compromise)**. Contrary to common belief, this is not primarily caused by direct tracheal compression by the blood clot. Instead, the hematoma causes **venous and lymphatic congestion**, leading to rapid-onset **laryngeal edema**. This narrows the glottic opening, making it the most immediate life-threatening event. The clinical priority is to immediately open the wound at the bedside to evacuate the clot and relieve pressure. **2. Why Other Options are Incorrect:** * **B. Recurrent Laryngeal Nerve (RLN) Palsy:** While a serious complication leading to hoarseness (unilateral) or airway distress (bilateral), it is usually a result of direct intraoperative trauma or stretching, not typically the primary danger of a postoperative hematoma. * **C. Dysphagia:** Difficulty swallowing may occur due to local pain or edema, but it is never life-threatening in the acute postoperative period compared to airway loss. * **D. Shock:** The thyroid space is relatively small; the volume of blood required to cause hemorrhagic shock is rarely reached before the patient succumbs to airway obstruction. **3. High-Yield Clinical Pearls for NEET-PG:** * **Management:** If a patient develops respiratory distress and a tense neck swelling, the first step is **immediate bedside stitch removal/clot evacuation**, followed by a return to the OR. * **Most common cause of hematoma:** Slippage of a ligature on the **superior thyroid artery**. * **Timing:** Usually occurs within the first **6 to 24 hours** post-surgery. * **Tracheostomy:** Rarely needed if the hematoma is evacuated promptly.

Question 43: The Pemberton sign is seen in which of the following conditions?

A. Retrosternal goiter (Correct Answer)
B. Graves ophthalmopathy
C. Thyroid crisis
D. Addisonian crisis

Explanation: **Explanation:** **Pemberton’s Sign** is a clinical maneuver used to demonstrate latent superior vena cava (SVC) syndrome, most commonly caused by a **retrosternal goiter**. 1. **Mechanism (Why A is correct):** When a patient with a retrosternal goiter raises both arms above their head (Pemberton maneuver) for 30–60 seconds, the thyroid gland is pulled into the narrow thoracic inlet. This "corks" the inlet, compressing the internal jugular and subclavian veins against the clavicles and first ribs. This leads to facial congestion, cyanosis, inspiratory stridor, and elevated jugular venous pressure (JVP). 2. **Analysis of Incorrect Options:** * **B. Graves Ophthalmopathy:** Characterized by exophthalmos, lid lag, and proptosis due to retro-orbital fat and muscle inflammation, not venous obstruction. * **C. Thyroid Crisis (Storm):** A life-threatening hypermetabolic state presenting with fever, tachycardia, and delirium; it is a functional/metabolic emergency, not a mechanical obstructive one. * **D. Addisonian Crisis:** An acute adrenal insufficiency presenting with hypotension, hyponatremia, and hyperkalemia. **High-Yield Clinical Pearls for NEET-PG:** * **Definition of Retrosternal Goiter:** A goiter where >50% of the thyroid mass is below the plane of the thoracic inlet. * **Most Common Cause:** Extension of a multinodular goiter (MNG). * **Imaging Gold Standard:** CT scan of the neck and thorax is the investigation of choice to assess the extent of the goiter and tracheal deviation. * **Surgical Approach:** Most retrosternal goiters can be removed via a standard **cervical incision**; a sternotomy is required in less than 5% of cases (usually for recurrent or malignant cases).

Question 44: Long-standing multinodular goiter is most commonly associated with which type of thyroid malignancy?

A. Follicular carcinoma (Correct Answer)
B. Colloid carcinoma
C. Medullary carcinoma
D. Papillary carcinoma

Explanation: **Explanation:** The correct answer is **Follicular Carcinoma (Option A)**. **Why Follicular Carcinoma is correct:** The development of follicular carcinoma is strongly linked to areas of **endemic iodine deficiency** and the presence of **long-standing multinodular goiter (MNG)**. Chronic stimulation of the thyroid gland by elevated TSH levels (due to low iodine) leads to hyperplasia and the formation of nodules. Over time, these hyperplastic nodules can undergo malignant transformation into follicular carcinoma. This is why follicular carcinoma is more prevalent in "goiter belts." **Why other options are incorrect:** * **B. Colloid carcinoma:** This is not a recognized histological type of thyroid malignancy. Colloid nodules are benign features of a multinodular goiter. * **C. Medullary carcinoma:** This arises from the parafollicular C-cells (neuroendocrine cells) and is associated with RET proto-oncogene mutations or MEN 2 syndromes, not with iodine deficiency or long-standing MNG. * **D. Papillary carcinoma:** While this is the **most common** thyroid cancer overall, it is usually associated with radiation exposure and specific genetic mutations (BRAF, RET/PTC). It is more common in iodine-sufficient areas and does not have a primary association with long-standing MNG. **High-Yield Clinical Pearls for NEET-PG:** * **Most common thyroid cancer:** Papillary Carcinoma. * **Cancer associated with Iodine Deficiency/MNG:** Follicular Carcinoma. * **Mode of spread:** Papillary spreads via **Lymphatics**; Follicular spreads via **Blood** (Hematogenous to lungs/bones). * **Psammoma bodies:** Characteristic of Papillary Carcinoma. * **Diagnosis:** Follicular carcinoma **cannot** be diagnosed by FNAC (requires histological evidence of capsular or vascular invasion); Papillary carcinoma **can** be diagnosed by FNAC.

Question 45: Lateral aberrant thyroid refers to which of the following?

A. Lingual thyroid
B. Metastatic foci from primary in thyroid (Correct Answer)
C. Struma ovarii
D. Congenital thyroid abnormality

Explanation: **Explanation:** The term **"Lateral Aberrant Thyroid"** is a historical misnomer. In the past, it was believed that thyroid tissue found laterally in the neck (outside the midline) represented a developmental anomaly or "rest" of thyroid tissue. However, modern surgical pathology has established that **any thyroid tissue found in the lateral cervical lymph nodes is almost always a metastatic deposit from an occult or overt Papillary Thyroid Carcinoma (PTC).** **Analysis of Options:** * **Option B (Correct):** Metastatic foci from a primary thyroid malignancy (usually Papillary Carcinoma) are the most common cause of lateral thyroid tissue. Even if the primary thyroid gland appears normal on palpation, a microscopic focus is often present. * **Option A (Lingual Thyroid):** This is the most common form of **ectopic thyroid**, resulting from a failure of the thyroid to descend from the foramen caecum. It is located in the midline at the base of the tongue, not laterally. * **Option C (Struma Ovarii):** This is a specialized form of mature cystic teratoma where thyroid tissue makes up more than 50% of the tumor. It is located in the ovary, not the neck. * **Option D (Congenital Thyroid Abnormality):** While ectopic thyroid is a congenital abnormality, "Lateral Aberrant Thyroid" specifically refers to the clinical presentation of metastatic nodes, which is an acquired oncological process rather than a developmental failure. **High-Yield NEET-PG Pearls:** * **Rule of Thumb:** Any lateral neck mass containing thyroid tissue should be considered **metastatic Papillary Thyroid Carcinoma** until proven otherwise. * **Investigation of Choice:** FNAC of the lateral node and Ultrasound of the thyroid gland. * **Most common site of Ectopic Thyroid:** Lingual thyroid (90%). * **Thyroglossal Duct Cyst:** The most common congenital midline neck swelling; it moves upward on protrusion of the tongue.

Question 46: Which of the following is NOT true about medullary thyroid carcinoma?

A. It involves the parafollicular cells.
B. It is radiosensitive. (Correct Answer)
C. Amyloid stroma is present.
D. There is an elevated level of calcitonin.

Explanation: **Explanation:** Medullary Thyroid Carcinoma (MTC) is a unique neuroendocrine tumor derived from the **parafollicular C-cells** of the thyroid gland. These cells originate from the **ultimobranchial body** (neural crest cells) and are responsible for secreting **calcitonin**. 1. **Why Option B is the correct answer (False statement):** MTC is notoriously **radioresistant**. Unlike papillary or follicular thyroid cancers, MTC cells do not concentrate iodine because they are not derived from follicular epithelium. Furthermore, external beam radiation and chemotherapy have very limited efficacy. The primary and most effective treatment is **total thyroidectomy with central compartment neck dissection**. 2. **Analysis of other options:** * **Option A:** Correct. MTC arises from the C-cells (parafollicular cells), which secrete calcitonin. * **Option C:** Correct. A pathognomonic histological feature of MTC is the presence of **amyloid stroma**, which represents deposits of pro-calcitonin. This stains positive with **Congo Red** (showing apple-green birefringence). * **Option D:** Correct. **Calcitonin** is the primary tumor marker used for diagnosis, screening, and monitoring recurrence. **CEA** (Carcinoembryonic Antigen) is also frequently elevated. **High-Yield Clinical Pearls for NEET-PG:** * **Genetics:** 75% are sporadic; 25% are familial (associated with **MEN 2A and 2B** syndromes due to **RET proto-oncogene** mutations). * **Diagnosis:** Fine Needle Aspiration Cytology (FNAC) is the gold standard. * **Screening:** In familial cases, prophylactic thyroidectomy is recommended based on the specific RET mutation codon. * **Staining:** Positive for Calcitonin, Chromogranin A, and Synaptophysin.

Question 47: What is the treatment for a thyrotoxic patient with a nodule?

A. Surgery
B. Medical therapy
C. Radiotherapy (Correct Answer)
D. Antithyroid drugs followed by surgery

Explanation: ### Explanation The question describes a patient with **Toxic Adenoma** (a single hyperfunctioning nodule) or **Toxic Multinodular Goiter (TMNG)**. In these conditions, the nodule(s) act autonomously, independent of TSH control, leading to thyrotoxicosis. **Why Radiotherapy (Radioactive Iodine - RAI) is correct:** For a thyrotoxic patient with an autonomous nodule, **Radioactive Iodine ($I^{131}$)** is the definitive treatment of choice, especially in adults. The "hot" nodule avidly takes up the isotope, leading to localized destruction of the overactive tissue while sparing the suppressed, normal thyroid parenchyma. This results in a high cure rate with a lower risk of permanent hypothyroidism compared to Graves' disease. **Analysis of Incorrect Options:** * **Medical therapy (Antithyroid drugs):** These (e.g., Carbimazole) are used to achieve a euthyroid state but are **not definitive**. Unlike Graves' disease, toxic nodules never undergo spontaneous remission; symptoms will recur once drugs are stopped. * **Surgery:** While surgery (Hemithyroidectomy) is a definitive option, it is generally reserved for very large nodules causing compressive symptoms, suspected malignancy, or patients who are pregnant/refuse radiation. In standard MCQ patterns, RAI is preferred for its non-invasive nature. * **Antithyroid drugs followed by surgery:** This is the standard protocol for **Graves' disease** or large TMNGs to prevent thyroid storm during surgery, but it is not the primary "first-line" definitive recommendation for a single toxic nodule unless specific surgical indications exist. **Clinical Pearls for NEET-PG:** * **Investigation of choice:** Thyroid Scintigraphy (Scan). A "Hot Nodule" with suppressed background uptake confirms the diagnosis. * **Plummer’s Disease:** Another name for Toxic Multinodular Goiter. * **Marine-Lenhart Syndrome:** Graves' disease co-existing with an autonomous functioning nodule. * **Contraindication:** RAI is strictly contraindicated in pregnancy and breastfeeding.

Question 48: Which of the following statements are true regarding papillary carcinoma of the thyroid in comparison to follicular carcinoma of the thyroid?

A. Male preponderance, bilaterality, and local recurrence are common
B. Bilaterality, local recurrence, and increased mortality are common
C. Bilaterality, local recurrence, and increased lymph node metastasis are common (Correct Answer)
D. Male preponderance, local recurrence, and increased lymph node metastasis are common

Explanation: ### Explanation **Papillary Thyroid Carcinoma (PTC)** is the most common thyroid malignancy. Understanding its behavior compared to **Follicular Thyroid Carcinoma (FTC)** is high-yield for NEET-PG. **Why Option C is Correct:** * **Bilaterality:** PTC is frequently multifocal and bilateral (up to 30-80% of cases depending on the study), whereas FTC is typically a solitary encapsulated lesion. * **Lymph Node Metastasis:** PTC is **lymphophilic**. It spreads primarily via the lymphatic system to cervical lymph nodes (level II-V and VI). In contrast, FTC is **hematogenous**, spreading via the blood to bones and lungs. * **Local Recurrence:** Due to its multifocality and lymphatic spread, PTC has a higher tendency for local recurrence in the neck compared to FTC. **Analysis of Incorrect Options:** * **Options A & D (Male Preponderance):** These are incorrect because thyroid cancers, including PTC, are significantly more common in **females** (approx. 3:1 ratio). * **Option B (Increased Mortality):** This is incorrect. PTC actually has a **better prognosis** and lower mortality rate than FTC. FTC is considered more aggressive due to its early distant hematogenous spread. **High-Yield Clinical Pearls for NEET-PG:** * **Most common type:** PTC is the most common thyroid cancer (85%). * **Risk Factor:** Prior exposure to **ionizing radiation** is the strongest risk factor for PTC. * **Histology (Must know):** Look for **Orphan Annie eye nuclei**, **Psammoma bodies** (calcifications), and **Nuclear grooves/pseudoinclusions**. * **Diagnosis:** PTC can be diagnosed via FNAC (nuclear features are visible). **FTC cannot be diagnosed by FNAC**; it requires histopathology to see capsular or vascular invasion. * **Prognostic Scoring:** AMES, MACIS, and TNM are used to predict outcomes.

Question 49: Which complication following thyroidectomy poses the greatest risk of acute respiratory distress?

A. Damage to the external laryngeal nerve
B. Unilateral complete damage to the recurrent laryngeal nerve
C. Unilateral partial damage to the recurrent laryngeal nerve
D. Bilateral partial damage to the recurrent laryngeal nerve (Correct Answer)

Explanation: ### Explanation The Recurrent Laryngeal Nerve (RLN) supplies all intrinsic muscles of the larynx except the cricothyroid. The clinical presentation of RLN injury depends on whether the damage is unilateral or bilateral, and whether it is partial or complete. **Why Option D is Correct:** In **bilateral partial damage**, the abductor fibers (which are more susceptible to injury, known as **Semon’s Law**) are paralyzed, while the adductor fibers may still function or retain tone. This causes the vocal cords to be pulled into a **median or paramedian position**, effectively closing the glottis. This results in acute, life-threatening respiratory distress and inspiratory stridor immediately following extubation, often requiring an emergency tracheostomy. **Analysis of Incorrect Options:** * **Option A:** Damage to the **External Laryngeal Nerve** paralyzes the cricothyroid muscle. This leads to a loss of tension in the vocal cords, manifesting as voice fatigue or loss of high-pitched notes, but does not cause respiratory distress. * **Option B:** **Unilateral complete damage** results in the affected cord assuming a paramedian position. The contralateral cord usually compensates, leading to hoarseness but no airway compromise. * **Option C:** **Unilateral partial damage** also results in hoarseness; the airway remains patent because the other vocal cord can still abduct. **NEET-PG High-Yield Pearls:** * **Semon’s Law:** In progressive nerve lesions, abductor fibers (posterior cricoarytenoid) are more vulnerable and perish before adductor fibers. * **Most common nerve injured** during thyroidectomy: External Laryngeal Nerve (during ligation of superior thyroid artery). * **Most serious nerve injury:** Bilateral Recurrent Laryngeal Nerve injury. * **Wagner and Grossman Hypothesis:** Explains that if the Superior Laryngeal Nerve is intact, the cricothyroid muscle keeps the cords adducted in RLN palsy.

Question 50: All of the following are true regarding medullary carcinoma of the thyroid except?

A. Total thyroidectomy is performed.
B. Parafollicular cells are involved.
C. It is TSH dependent. (Correct Answer)
D. Calcitonin is released.

Explanation: **Explanation:** Medullary Carcinoma of the Thyroid (MCT) is a neuroendocrine tumor arising from the **parafollicular C-cells**, which are derived from the **ultimobranchial body** (neural crest cells). **Why Option C is the Correct Answer (The False Statement):** Unlike papillary and follicular carcinomas, which arise from follicular cells and are regulated by Thyroid Stimulating Hormone (TSH), MCT arises from C-cells. These cells do not possess TSH receptors; therefore, **MCT is TSH-independent**. Consequently, TSH suppression therapy (using Levothyroxine) has no role in the management of MCT. **Analysis of Other Options:** * **Option A:** Total thyroidectomy is the treatment of choice. Because MCT is often multicentric (especially in familial cases) and does not concentrate iodine, aggressive surgical resection and central neck dissection are mandatory. * **Option B:** MCT originates from the **parafollicular cells** (C-cells), which are responsible for secreting calcitonin. * **Option D:** **Calcitonin** is the primary tumor marker for MCT. It is used for diagnosis, screening of family members, and monitoring for postoperative recurrence. **High-Yield Clinical Pearls for NEET-PG:** * **Tumor Marker:** Calcitonin (for diagnosis) and CEA (for prognosis). * **Histology:** Characterized by **amyloid stroma** (stained with Congo Red showing apple-green birefringence). * **Genetics:** 75% are sporadic; 25% are familial (associated with **MEN 2A and 2B** syndromes). All patients with MCT should be screened for **RET proto-oncogene** mutations. * **Prophylaxis:** In MEN 2A/2B, prophylactic total thyroidectomy is recommended based on the specific RET mutation.

Practice by Chapter

Thyroid Nodules

Practice Questions

Thyroid Cancer

Practice Questions

Graves' Disease

Practice Questions

Thyroiditis

Practice Questions

Primary Hyperparathyroidism

Practice Questions

Secondary and Tertiary Hyperparathyroidism

Practice Questions

Adrenal Cortical Tumors

Practice Questions

Pheochromocytoma

Practice Questions

Adrenal Incidentalomas

Practice Questions

Multiple Endocrine Neoplasia

Practice Questions

Neuroendocrine Tumors

Practice Questions

Intraoperative Monitoring in Endocrine Surgery

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free