Endocrine Surgery

Endocrine Surgery Indian Medical PG Question 1: What is the most common thyroid tumor associated with multiple endocrine neoplasia (MEN)?

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

Endocrine Surgery Explanation: ***Medullary*** - The **commonest thyroid tumor** in Multiple Endocrine Neoplasia (MEN) type 2 is medullary thyroid carcinoma, associated with **calcitonin production** [1]. - It arises from **C cells (parafollicular cells)** and is linked to **RET oncogene mutations** in MEN syndromes [1]. *Papillary* - Papillary thyroid carcinoma is the **most common thyroid cancer overall**, but not specifically associated with MEN syndromes. - It typically presents with **lymphatic spread**, whereas medullary carcinoma has a different genetic association. *Follicular* - Follicular thyroid carcinoma is less common in MEN and usually occurs sporadically. - It primarily arises from **follicular cells** and involves a different mechanism than medullary carcinoma. *Anaplastic* - Anaplastic thyroid carcinoma is a rare and highly aggressive form, not commonly associated with MEN. - It usually arises from **differentiated thyroid cancers** and presents in older patients, which does not align with MEN's typical presentations. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1102-1103.

Endocrine Surgery Indian Medical PG Question 2: Which type of thyroid cancer is associated with primary hyperparathyroidism and phaeochromocytoma?

• A. Medullary carcinoma of the thyroid (Correct Answer)
• B. Papillary carcinoma of the thyroid
• C. Anaplastic carcinoma of the thyroid
• D. Follicular carcinoma of the thyroid

Endocrine Surgery Explanation: ***Medullary carcinoma of the thyroid*** - Associated with **multiple endocrine neoplasia (MEN) syndrome type 2**, which includes primary hyperparathyroidism and phaeochromocytoma [1]. - Medullary carcinoma arises from **C cells** (parafollicular cells) and is linked with **elevated calcitonin** levels. *Papillary carcinoma of the thyroid* - The most common type of thyroid cancer, but **not associated** with MEN syndromes. - Typically presents as a solitary **nodule** and is linked with **radiation exposure** rather than endocrine syndromes. *Anaplastic carcinoma of the thyroid* - A highly aggressive and undifferentiated form of thyroid cancer, often associated with **poor prognosis**. - Usually arises in older adults and does not have associations with **hyperparathyroidism** or phaeochromocytoma. *Follicular carcinoma of the thyroid* - Characterized by **thyroid follicle formation** and can be associated with **iodine deficiency**, but not with MEN syndromes. - It usually presents as a **solitary thyroid nodule** and lacks connection with **primary hyperparathyroidism**.

Endocrine Surgery Indian Medical PG Question 3: Submucosal neuroma is associated with

• A. MEN 2 A
• B. MEN 2B (Correct Answer)
• C. MEN 1
• D. None of the options

Endocrine Surgery Explanation: ***MEN 2B (Multiple Endocrine Neoplasia Type 2B)*** - **Submucosal neuromas** are a distinctive feature of MEN 2B, specifically noticeble as mucosal neuromas on the lips, tongue, and gastrointestinal tract. - This syndrome is characterized by the presence of **medullary thyroid carcinoma**, **pheochromocytoma**, and mucocutaneous neuromas, without hyperparathyroidism. *MEN 2A (Multiple Endocrine Neoplasia Type 2A)* - MEN 2A is characterized by **medullary thyroid carcinoma**, **pheochromocytoma**, and **primary hyperparathyroidism**. - It does not typically feature extensive **submucosal neuromas** as a primary diagnostic criterion. *MEN 1 (Multiple Endocrine Neoplasia Type 1)* - MEN 1 involves tumors of the **parathyroid glands**, **anterior pituitary**, and **pancreatic islet cells** (the '3 Ps'). - **Submucosal neuromas** are not a component of the MEN 1 syndrome. *None of the options* - This option is incorrect because **submucosal neuromas** are a characteristic finding in MEN 2B.

Endocrine Surgery Indian Medical PG Question 4: Radiation exposure can lead to which type of thyroid carcinoma?

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

Endocrine Surgery Explanation: ***Papillary carcinoma*** - Papillary thyroid carcinoma is strongly associated with **radiation exposure**, particularly during childhood [1]. - It is the most prevalent type of thyroid cancer and typically has a **good prognosis** [1]. *Lymphoma* - Thyroid lymphoma is rare and generally not linked to **radiation exposure**; it often presents as a **rapidly enlarging goiter**. - It is more commonly associated with **autoimmune thyroiditis**, not primary radiation effects. *Follicular carcinoma* - Follicular carcinoma shows a correlation with **iodine deficiency** rather than radiation exposure [1]. - Its presentation is more subtle, compared to the classical association of **radiation with papillary carcinoma**. *Medullary carcinoma* - Medullary thyroid carcinoma is primarily linked to **familial syndromes** like MEN 2 and not radiation exposure. - It arises from **parafollicular C cells**, making it clinically distinct from radiation-related types. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1098-1099.

Endocrine Surgery Indian Medical PG Question 5: What is the correct sequence of medication administration for pre-operative prophylaxis in pheochromocytoma?

• A. Beta blockade followed by alpha blockade
• B. Simultaneous alpha and beta blockade
• C. Alpha blockade followed by beta blockade (Correct Answer)
• D. Alpha blockade only

Endocrine Surgery Explanation: ***Alpha blockade followed by beta blockade*** - **Alpha blockade** should always be initiated first to control **hypertension** and prevent a **hypertensive crisis** during surgery. This is critical because pheochromocytoma causes excessive catecholamine release, leading to profound vasoconstriction. - **Beta blockade** is then added only after adequate alpha blockade has been achieved to control **tachycardia** and arrhythmias, preventing **unopposed alpha-adrenergic stimulation** which could paradoxically worsen hypertension. *Simultaneous alpha and beta blockade* - Administering both simultaneously is dangerous because **beta blockade** can mask the effects of inadequate alpha blockade. - This can lead to **unopposed alpha-adrenergic stimulation** after beta blockade, causing severe **vasoconstriction** and hypertensive crisis. *Beta blockade followed by alpha blockade* - Initiating with **beta blockade** without prior **alpha blockade** is absolutely contraindicated in pheochromocytoma. - This can lead to severe and potentially fatal **hypertension** due to **unopposed alpha-adrenergic stimulation** as beta blockade prevents vasodilation. *Alpha blockade only* - While essential for initial management, **alpha blockade alone** might not fully control all symptoms, especially **tachycardia** and **arrhythmias** caused by high circulating catecholamine levels. - Adding a **beta blocker** after achieving adequate alpha blockade helps in controlling these cardiac effects, optimizing patient preparation for surgery.

Endocrine Surgery Flashcard 1 of 5

Question: According to the Bethesda system (Thyroid cytopathology), what is the preferred line of Mx for Criteria V?_____

Answer: Lobectomy or total thyroidectomy

Endocrine Surgery Flashcard 2 of 5

Question: _____ post a thyroidectomy is the most frequent life threatening complication.

Answer: Hemorrhage

Endocrine Surgery Flashcard 3 of 5

Question: The following resection is done in a _____thyroidectomy

Answer: near total

Endocrine Surgery Flashcard 4 of 5

Question: Parathyroid graft hyperplasia, post parathyroidectomy in a pt. with persistent HPT is diagnosed by the _____ test

Answer: Casanova

Endocrine Surgery Flashcard 5 of 5

Question: The usual cause of thyroid storm in thyroidectomy is _____

Answer: inadequate patient preparation before surgery.