Endocrine Surgery — MCQs

Endocrine Surgery Indian Medical PG Practice Questions and MCQs

Question 11: What is the standard incision used in thyroidectomy?

A. Barking incision
B. Collar incision (Correct Answer)
C. Kocher incision
D. Koebner incision

Explanation: The standard surgical approach for a thyroidectomy is the **Collar incision**, specifically known as the **Kocher’s transverse collar incision**. ### **Explanation of the Correct Answer** The **Collar incision** is a transverse, curvilinear incision made approximately 2 cm (two fingerbreadths) above the suprasternal notch. It is ideally placed within a natural skin crease (Langer’s lines) to ensure optimal cosmesis and minimal scarring. The incision extends through the skin, subcutaneous fat, and platysma to provide symmetrical access to both lobes of the thyroid gland. ### **Analysis of Incorrect Options** * **Barking incision:** This is a distractor term and is not a recognized surgical incision in standard textbooks. * **Kocher incision:** While Emil Theodor Kocher described the collar incision, the term "Kocher incision" (without the word "collar") most commonly refers to the **subcostal incision** used for open cholecystectomy or biliary tract surgery. * **Koebner incision:** This is a distractor. The "Koebner phenomenon" is a dermatological term referring to the appearance of skin lesions at the site of trauma; it is not a surgical incision. ### **High-Yield Clinical Pearls for NEET-PG** * **Placement:** The incision must be symmetrical. If placed too low (over the sternum), it may result in a hypertrophic or keloid scar. * **Platysma:** This is the first muscle layer encountered; subplatysmal flaps (superior and inferior) are raised to provide adequate exposure. * **Nerve Safety:** During thyroidectomy, the two most critical nerves to identify and preserve are the **Recurrent Laryngeal Nerve (RLN)** (injury causes hoarseness/vocal cord palsy) and the **External branch of the Superior Laryngeal Nerve** (injury causes loss of high-pitched voice). * **Vascular Ligation:** To protect these nerves, the **superior thyroid artery** is ligated close to the gland, while the **inferior thyroid artery** is ligated well away from the gland.

Question 12: The specimen shown below is:

A. MNG (Multinodular goiter) (Correct Answer)
B. SNT (Solitary nodule thyroid)
C. Adenoma thyroid
D. TG cyst (Thyroid cyst)

Explanation: ***MNG (Multinodular goiter)*** - The specimen shows **multiple nodules** of varying sizes with **irregular cut surface** containing both **solid and cystic areas** with **colloid-filled spaces**. - Characteristic **heterogeneous appearance** with **fibrotic bands** separating nodules and absence of a **single dominant encapsulated mass**. *SNT (Solitary nodule thyroid)* - Would present as a **single well-defined nodule** within otherwise normal thyroid tissue, not multiple nodules. - The **cut surface** would show **uniform appearance** of a solitary mass, contrasting with the multinodular pattern seen here. *Adenoma thyroid* - Appears as a **single encapsulated nodule** with a **smooth, uniform cut surface** and **complete fibrous capsule**. - Lacks the **multiple nodules** and **heterogeneous appearance** characteristic of this specimen. *TG cyst (Thyroid cyst)* - Would show a **single cystic cavity** filled with **clear or hemorrhagic fluid** without solid nodular components. - Lacks the **multiple solid nodules** and **varied architectural pattern** evident in this multinodular specimen.

Question 13: What is tense and painful thyroiditis?

A. De Quervain thyroiditis (Correct Answer)
B. Riedel thyroiditis
C. Hashimoto thyroiditis
D. Subacute lymphocytic thyroiditis

Explanation: **Explanation:** The correct answer is **De Quervain thyroiditis (Subacute Granulomatous Thyroiditis)**. **Why it is correct:** De Quervain thyroiditis is classically characterized by a **painful, tender, and firm (tense)** thyroid gland. It is typically a post-viral inflammatory condition. The pain is often severe, localized to the anterior neck, and may radiate to the jaw or ears. On histology, it is characterized by **multinucleated giant cells** and granulomatous inflammation. Patients often present with an elevated ESR and a low radioactive iodine uptake (RAIU) due to follicular destruction. **Why the other options are incorrect:** * **Riedel thyroiditis:** Known as "woody" or "iron-hard" thyroiditis due to dense fibrous tissue replacement. While the gland is very hard and fixed, it is typically **painless**. * **Hashimoto thyroiditis:** The most common cause of hypothyroidism. It presents as a diffuse, rubbery, **painless** goiter. It is an autoimmune destruction mediated by antithyroid peroxidase (TPO) antibodies. * **Subacute lymphocytic thyroiditis:** Also known as "painless thyroiditis" or "silent thyroiditis." It often occurs postpartum and, as the name suggests, lacks the tenderness seen in De Quervain’s. **High-Yield Clinical Pearls for NEET-PG:** * **Triad of De Quervain:** Painful neck swelling + Elevated ESR + Low Iodine Uptake. * **Treatment:** NSAIDs are the first-line treatment for pain; oral corticosteroids are used for refractory or severe cases. * **Biphasic Course:** It often starts with a transient hyperthyroid phase (leakage of preformed hormone) followed by a hypothyroid phase before returning to euthyroidism. * **Key Histology:** "Granulomas with Giant Cells" is the pathognomonic buzzword.

Question 14: Which of the following carcinomas shows a good response to radioiodine?

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

Explanation: **Explanation:** The effectiveness of **Radioactive Iodine (RAI/I-131) therapy** depends on the expression of the **Sodium-Iodide Symporter (NIS)** and the degree of cellular differentiation. **Why Follicular Carcinoma (FTC) is the correct answer:** Follicular carcinoma is a well-differentiated thyroid cancer that retains the functional machinery of normal follicular cells. It has a high affinity for iodine uptake, often even more consistently than papillary carcinoma in metastatic settings. Because FTC tends to spread **hematogenously** (to lungs and bone), RAI is the mainstay for treating distant metastases, showing an excellent therapeutic response. **Analysis of Incorrect Options:** * **A. Papillary Carcinoma (PTC):** While PTC is also well-differentiated and responds to RAI, it primarily spreads via **lymphatics**. In a comparative context for NEET-PG, FTC is often highlighted for its superior reliance on RAI for managing systemic spread. However, both are "RAI-responsive." * **C. Anaplastic Carcinoma:** This is an undifferentiated tumor. It loses all functional characteristics of thyroid tissue, including the NIS protein, making it completely **resistant** to radioiodine. * **D. Medullary Carcinoma (MTC):** MTC arises from **Parafollicular C-cells**, which do not concentrate iodine. Therefore, RAI has no role in its management. **High-Yield Clinical Pearls for NEET-PG:** * **Prerequisite for RAI:** Patients must have high TSH levels (>30 mIU/L) or receive recombinant TSH to maximize iodine uptake before therapy. * **Diagnostic vs. Therapeutic:** I-123 is preferred for imaging (diagnostic), while **I-131** is used for ablation (therapeutic) due to its high-energy beta-particle emission. * **Marker of Recurrence:** After total thyroidectomy and RAI ablation, **Serum Thyroglobulin** serves as the primary tumor marker for PTC and FTC.

Question 15: A middle-aged female presents to the surgical OPD with a thyroid swelling. She has a history of Hodgkin's lymphoma. Which of the following thyroid malignancies is most likely to be suspected in this patient?

A. Papillary thyroid cancer (Correct Answer)
B. Medullary thyroid cancer
C. Anaplastic thyroid cancer
D. Thyroid lymphoma

Explanation: **Explanation:** The correct answer is **Papillary Thyroid Cancer (PTC)**. The key clinical association in this question is the history of **Hodgkin’s lymphoma**. Patients treated for Hodgkin’s lymphoma often receive mantle field radiation therapy. **Ionizing radiation** is the most significant and well-established risk factor for the development of Papillary Thyroid Cancer. There is a long latency period (often 10–20 years) between radiation exposure and the appearance of the malignancy. **Analysis of Options:** * **Papillary Thyroid Cancer (Correct):** It is the most common thyroid malignancy overall and specifically the one most strongly associated with prior radiation exposure. * **Medullary Thyroid Cancer:** This arises from parafollicular C-cells and is primarily associated with genetic mutations (RET proto-oncogene) and MEN 2 syndromes, not radiation. * **Anaplastic Thyroid Cancer:** While aggressive, it typically presents in elderly patients and is not the primary malignancy linked to prior lymphoma-related radiation. * **Thyroid Lymphoma:** Although the patient has a history of Hodgkin’s lymphoma, primary thyroid lymphoma is rare and is most strongly associated with **Hashimoto’s thyroiditis**, not prior radiation. **Clinical Pearls for NEET-PG:** * **Most common thyroid cancer post-radiation:** Papillary Thyroid Cancer. * **Genetic association:** *BRAF* mutation is the most common mutation in PTC; *RET/PTC* rearrangements are specifically associated with radiation-induced PTC. * **Psammoma bodies:** Characteristic histological finding (laminated calcifications) in PTC. * **Orphan Annie eye nuclei:** Classic nuclear clearing seen on histopathology of PTC.

Question 16: Which of the following statements regarding follicular cell carcinoma of the thyroid is true?

A. Hematogenous spread (Correct Answer)
B. Commonly multifocal
C. Readily diagnosed by FNAC
D. Most common carcinoma of the thyroid

Explanation: **Follicular Thyroid Carcinoma (FTC)** is the second most common thyroid malignancy. Understanding its unique pathological behavior is crucial for NEET-PG. ### **Explanation of the Correct Option** * **A. Hematogenous spread:** Unlike Papillary Thyroid Carcinoma (PTC), which primarily spreads via the lymphatic system, FTC characteristically spreads via the **bloodstream (hematogenous)**. This occurs because the tumor cells invade thin-walled blood vessels. Consequently, distant metastases to the **lungs and bones** (often osteolytic) are more common than regional lymph node involvement. ### **Why the Other Options are Incorrect** * **B. Commonly multifocal:** FTC is typically a **solitary, encapsulated lesion**. Multifocality is a hallmark of Papillary Thyroid Carcinoma (PTC). * **C. Readily diagnosed by FNAC:** This is a classic "trap" question. FNAC **cannot** distinguish between a benign Follicular Adenoma and a malignant Follicular Carcinoma. Both show follicular cells on cytology. The diagnosis of malignancy requires histological evidence of **capsular or vascular invasion**, which can only be seen on a formal biopsy/resection. * **D. Most common carcinoma:** **Papillary Thyroid Carcinoma (PTC)** is the most common thyroid cancer (approx. 80-85%), whereas FTC accounts for about 10-15%. ### **High-Yield Clinical Pearls for NEET-PG** * **Risk Factor:** More common in **iodine-deficient** areas (unlike PTC, which is associated with radiation and iodine excess). * **Hürthle Cell Carcinoma:** A variant of FTC; it is more aggressive, less likely to take up radioactive iodine, and more likely to spread to lymph nodes. * **Molecular Marker:** Often associated with **RAS mutations** or **PAX8-PPARγ rearrangements**. * **Treatment:** Total thyroidectomy followed by Radioactive Iodine (RAI) ablation, as FTC cells usually retain the ability to concentrate iodine.

Question 17: What is the recommended treatment for papillary carcinoma of the thyroid with lymph node metastasis at level VI?

A. Total thyroidectomy
B. Total thyroidectomy plus central neck dissection (Correct Answer)
C. Total thyroidectomy plus radioiodine ablation
D. Total thyroidectomy plus radical neck dissection

Explanation: **Explanation:** The management of Papillary Thyroid Carcinoma (PTC) is guided by the extent of the primary tumor and the presence of regional metastases. **Why Option B is Correct:** The presence of lymph node metastasis at **Level VI (Central Compartment)** is a definitive indication for therapeutic **Central Neck Dissection (CND)**. The central compartment includes the pre-tracheal, para-tracheal, and pre-laryngeal (Delphian) nodes. For any clinically involved nodes (cN1a) in PTC, the standard of care is a **Total Thyroidectomy** combined with a clearance of these nodes to reduce the risk of local recurrence and facilitate post-operative monitoring with Thyroglobulin levels. **Why Other Options are Incorrect:** * **Option A:** Total thyroidectomy alone is insufficient when nodal disease is clinically evident. Leaving involved nodes increases the risk of persistence and recurrence. * **Option C:** Radioiodine (RAI) ablation is an adjuvant therapy used *after* surgery to destroy residual microscopic disease or distant metastases; it is not a substitute for the surgical clearance of gross nodal disease. * **Option D:** Radical Neck Dissection (RND) involves removing the Sternocleidomastoid muscle, Internal Jugular Vein, and Spinal Accessory Nerve. This is considered overly morbid and is rarely indicated for PTC. If lateral nodes (Levels II-V) were involved, a *Modified* Radical Neck Dissection (MRND) would be the preferred choice. **High-Yield Clinical Pearls for NEET-PG:** * **Level VI Nodes:** Boundaries are the Hyoid bone (superior), Suprasternal notch (inferior), and Carotid arteries (lateral). * **Prognosis:** PTC has an excellent prognosis; however, lymph node metastasis is common (up to 50-70%) but does not significantly alter overall survival in younger patients. * **Prophylactic CND:** Controversial; generally considered for advanced primary tumors (T3/T4) even if nodes are clinically negative (cN0).

Question 18: What is the treatment for a brown tumor?

A. Curettage
B. Surgical enucleation
C. Intralesional steroids
D. Parathyroidectomy (Correct Answer)

Explanation: **Explanation:** A **Brown tumor** (osteitis fibrosa cystica) is not a true neoplasm but a reactive bone lesion caused by **Primary Hyperparathyroidism (PHPT)**. The underlying pathophysiology involves excessive secretion of Parathyroid Hormone (PTH), which stimulates osteoclastic activity. This leads to bone resorption and the replacement of marrow with vascular fibrous tissue and giant cells. The "brown" color is due to hemosiderin deposition from micro-hemorrhages. **Why Parathyroidectomy is the correct answer:** The definitive treatment for a brown tumor is addressing the source of excess PTH. Once the offending parathyroid adenoma or hyperplasia is surgically removed (**Parathyroidectomy**), PTH levels normalize, and the brown tumor typically undergoes spontaneous regression and mineralization over several months. **Why other options are incorrect:** * **A & B (Curettage/Surgical enucleation):** These are local treatments for true bone tumors (like Giant Cell Tumors). In the case of a brown tumor, local surgery is unnecessary and carries a risk of recurrence if the systemic hyperparathyroidism is not corrected. * **C (Intralesional steroids):** These are sometimes used for aneurysmal bone cysts or giant cell granulomas but have no role in treating the metabolic bone disease of hyperparathyroidism. **NEET-PG High-Yield Pearls:** * **Radiological Hallmark:** Subperiosteal bone resorption, most commonly seen on the **radial aspect of the middle phalanges**. * **Skull finding:** "Salt and pepper" appearance. * **Biochemical profile:** Elevated Serum Calcium, Elevated PTH, and Low Serum Phosphate. * **Differential Diagnosis:** Histologically, brown tumors are indistinguishable from **Giant Cell Tumors (GCT)**; always check serum calcium/PTH to differentiate.

Question 19: During bilateral adrenalectomy, what is the appropriate timing for the intra-operative dose of hydrocortisone?

A. Opening the abdomen
B. Ligation of the left adrenal vein
C. Ligation of the right adrenal vein
D. Excision of both adrenal glands (Correct Answer)

Explanation: **Explanation:** The goal of intra-operative steroid management during a bilateral adrenalectomy is to prevent **acute adrenal insufficiency (Addisonian crisis)** while ensuring the patient has sufficient glucocorticoid cover once their endogenous source is removed. **Why Option D is Correct:** The physiological rationale is that as long as one adrenal gland (or even a portion of it) remains vascularized and functional, it can continue to secrete cortisol into the systemic circulation. Therefore, the critical moment of potential steroid deficiency occurs only after **both glands have been excised** or their venous drainage has been completely severed. Administering the bolus dose of hydrocortisone (typically 100mg IV) at the time of excision ensures a seamless transition from endogenous to exogenous steroids. **Why Other Options are Incorrect:** * **Option A (Opening the abdomen):** This is too early. The patient’s own adrenals are still functioning and responding to the stress of surgery. * **Options B & C (Ligation of left/right vein):** Ligating only one vein leaves the contralateral gland functional. Even if the right adrenal vein (the more technically challenging one) is ligated first, the left gland provides sufficient hormonal cover. The "point of no return" for hormonal production is only reached when the second gland is removed. **High-Yield Clinical Pearls for NEET-PG:** * **Standard Regimen:** 100 mg Hydrocortisone IV is given during the induction of anesthesia, followed by another 100 mg at the time of gland excision. * **Post-op Taper:** Steroids are tapered over 5–7 days to a maintenance dose (e.g., Oral Hydrocortisone 20mg morning/10mg evening). * **Nelson’s Syndrome:** A high-yield complication of bilateral adrenalectomy for Cushing’s Disease, characterized by an ACTH-secreting pituitary adenoma, skin hyperpigmentation, and visual field defects. * **Anatomical Note:** The right adrenal vein is short and drains directly into the IVC; the left adrenal vein is longer and drains into the left renal vein.

Question 20: All are true about the effect of thymectomy, EXCEPT:

A. Thymectomy results in the resolution of pure red cell aplasia in approximately 30% of patients.
B. Hypogammaglobulinemia usually responds to thymectomy. (Correct Answer)
C. Patients with myasthenia gravis have a thymoma in 10-15% of cases.
D. The course of myasthenia gravis is not significantly different in patients with or without thymoma.

Explanation: ### Explanation **1. Why Option B is the Correct Answer (The Exception):** Hypogammaglobulinemia associated with a thymoma is known as **Good’s Syndrome**. This is a rare paraneoplastic syndrome characterized by thymoma, low circulating B-cells, and hypogammaglobulinemia. Unlike Myasthenia Gravis (MG), the immune deficiency in Good’s Syndrome is **not reversed by thymectomy**. Patients remain at high risk for recurrent infections and usually require lifelong intravenous immunoglobulin (IVIG) replacement. **2. Analysis of Other Options:** * **Option A:** Pure Red Cell Aplasia (PRCA) is associated with thymoma in about 5% of cases. Surgical removal of the thymus leads to hematologic remission in approximately **30-50%** of these patients. * **Option C:** This is a classic high-yield statistic. Approximately **10-15% of patients with MG** have an underlying thymoma. Conversely, about 30-45% of patients with a thymoma will have MG. * **Option D:** While thymectomy is more urgently indicated in thymoma (due to malignant potential), the **neuromuscular course of MG** (severity of weakness and response to medical therapy) does not differ significantly between those with a thymoma and those with non-thymomatous lymphoid hyperplasia. **3. Clinical Pearls for NEET-PG:** * **Most common mediastinal tumor:** Thymoma (specifically in the anterior mediastinum). * **Indications for Thymectomy in MG:** All patients with thymoma; and patients without thymoma who are between puberty and age 60 with generalized symptoms. * **Good’s Syndrome Triad:** Thymoma + Hypogammaglobulinemia + Low B-cells (Thymectomy does *not* help the B-cell count). * **Post-operative care:** Patients with MG are at risk of "Myasthenic Crisis" post-surgery; plasmapheresis is often used pre-operatively to optimize respiratory status.

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