NEET-PG 2012 Practice Questions

Q: Most common site for medulloblastoma is-

Cerebellum. ***Cerebellum*** - **Medulloblastoma** is a highly malignant primary brain tumor that characteristically arises in the **cerebellum** [1]. - It is the most common malignant brain tumor in children, typically originating from the **roof of the fourth ventricle**. *Pituitary* - The **pituitary gland** is mostly associated with **adenomas**, which are benign tumors arising from anterior pituitary cells. - Tumors like **craniopharyngiomas** can also be found in the sellar region, but medulloblastomas do not originate here. *Cerebrum* - The **cerebrum** is the most common site for **gliomas** (e.g., glioblastoma multiforme) and metastatic tumors in adults. - Medulloblastoma specifically originates from primitive neuroectodermal cells in the posterior fossa [1]. *Pineal gland* - The **pineal gland** is associated with **pinealomas** (e.g., pineoblastoma, pineocytoma) and **germinomas** [2]. - These are distinct from medulloblastomas in their cellular origin and typical anatomical location.

Q: Orphan Annie nuclei are characteristic of which of the following?

Papillary thyroid carcinoma. ***Papillary carcinoma thyroid***[1][2] - Characterized by **Orphan Annie nuclei**[1], which are large and round with a clear or empty appearance due to the presence of intranuclear cytoplasmic inclusions[1]. - Often associated with **thyroid follicular structures** and is the most common type of thyroid cancer[2]. *Meningioma* - Typically presents with **dural-based tumors** and does not exhibit Orphan Annie nuclei. - Histologically, it may demonstrate **whorled patterns** or calcifications instead. *Carcinoma pituitary* - Involves **adenomatous changes** in the pituitary gland but does not demonstrate the characteristic Orphan Annie nuclei. - More commonly shows **varied cellular morphology** depending on the type of secretory cells (e.g., prolactin, ACTH). *Paraganglioma* - Derived from **neuroendocrine cells**, and presents with **zellballen pattern** rather than Orphan Annie nuclei. - Often shows **chromaffin cells** and is typically associated with catecholamine secretion. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, p. 1099. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 429-430.

Q: Which of the following is the most likely proliferating breast mass?

Fibroadenoma. **Fibroadenoma** - A **fibroadenoma** is a benign **biphasic breast tumor** composed of both glandular and stromal tissue, making it a common proliferating mass [3]. - It is often seen in **young women** and typically presents as a firm, movable, non-tender lump [3]. *Duct ectasia* - **Duct ectasia** is a non-proliferative condition characterized by dilation of the **subareolar ducts**, often with inflammation and fibrosis. - It is more commonly associated with **nipple discharge** and **periductal inflammation** rather than being a primary proliferating mass. *Adenosis* - **Adenosis** refers to an increase in the number of **glands or lobules** within the breast parenchyma, which can be sclerosing or florid [2]. - While it involves increased glandular elements, it is generally considered a **benign proliferative change** and less likely to form a distinct, palpable mass compared to a fibroadenoma [1], [4]. *Papilloma* - A **papilloma** is a benign epithelial proliferation within a **duct**, characterized by a central fibrovascular core [2]. - It commonly presents with **nipple discharge**, often bloody, and is typically a smaller lesion within the ductal system rather than a large, palpable proliferating mass [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Breast, pp. 1052-1054. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 446-447. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 448-449. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Breast, p. 1052.

Q: ER positive status in carcinoma breast indicates?

Prognosis. ***Prognosis*** - **ER positive status** in breast cancer indicates a better prognosis, as these tumors often respond well to hormone therapy [1][2]. - Patients with **ER positive** breast cancer usually have a lower risk of metastasis compared to **ER negative** tumors, making the outcome more favorable [1]. *Site* - ER status does not provide information regarding the **anatomical location** of the breast cancer, as it can be present in different sites of the breast. - It primarily focuses on the **biologic characteristics** of the tumor rather than its site of occurrence [1]. *None* - Selecting 'None' suggests that ER positive status has no relevance, which is incorrect as it is significant for treatment and prognosis [1]. - It is a crucial indicator for deciding on **endocrine therapy**, impacting management strategies in breast cancer patients [1]. *Etiology* - ER positive status does not directly indicate the **cause** of breast cancer, as various genetic and environmental factors contribute to its development. - It mainly reflects tumor behavior and response to therapies, not the **underlying factors** that lead to the disease [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Breast, p. 1056. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Breast, pp. 1064-1066.

Q: Which gene mutation is commonly associated with malignant melanoma?

CDKN2A. ***CDK2A*** - CDK2A mutations are implicated in malignant melanoma as they disrupt the **cell cycle regulation**, contributing to uncontrolled cell growth [1]. - Loss of CDK2A function leads to reduced **p16INK4A**, a crucial inhibitor of cyclin-dependent kinases involved in **G1/S phase transition** [1,3]. - Germline mutations of p16 (CDKN2A) are present in 25% of melanoma-prone kindreds [2], and germline mutations in CDKN2A are associated with familial forms of melanoma [3]. *RET* - RET mutations are primarily associated with **medullary thyroid carcinoma** and **multiple endocrine neoplasia type 2**, not melanoma. - It is involved in the signaling pathways but does not have a direct link to melanoma pathogenesis. *None* - Suggesting "none" misrepresents the reality that specific mutations do occur in malignant melanoma, including **CDK2A** and **BRAF**. - This option fails to recognize the importance of genetic alterations in cancer development and progression. *N-myc* - N-myc mutations are primarily associated with **neuroblastoma** and not typically linked to malignant melanoma. - In melanoma, mutations of this gene do not play a significant role in its pathophysiology compared to another tumor suppressor gene like **CDK2A**. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Skin, pp. 1150-1151. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 297-298. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 305-306.

Q: Which of the following best describes a Type B adverse drug reaction?

Unpredictable bizarre reaction. ***Unpredictable bizarre reaction*** - Type B reactions are **unpredictable**, **bizarre**, and not directly related to the drug's known pharmacological actions. - They often involve **immunological reactions** or genetic predispositions, such as allergies or idiosyncratic responses. *Augmented effect of drug* - This describes a **Type A** adverse drug reaction, which is predictable and results from an **exaggerated pharmacological effect** of the drug. - It is typically dose-dependent and can be managed by adjusting the dosage. *Effect seen on chronic use of drug* - This description can apply to several types of adverse reactions, but it commonly relates to **Type C (chronic) reactions**, where effects occur only after prolonged exposure. - These reactions might be due to **cumulative toxicity** or adaptive changes in the body. *Delayed effect of drug* - This aligns with **Type D (delayed) adverse drug reactions**, which manifest long after the drug exposure has ended or after a period of latency. - Examples include **carcinogenesis** or teratogenesis, occurring months or years later.

Q: Which of the following statements about dopamine is false?

Causes increase in GI Ischemia. ***Causes increase in GI Ischemia*** (FALSE Statement) - This statement is **incorrect and misleading** as dopamine does not primarily "cause increase in GI ischemia" - While dopamine at **higher doses** can cause **splanchnic vasoconstriction** via alpha-1 receptors, this is not characterized as "causing GI ischemia" in standard pharmacology - GI ischemia is a potential adverse effect in susceptible patients, but not a primary pharmacological effect or standard clinical description of dopamine *Positive inotropic* (TRUE Statement) - Dopamine is a **catecholamine** with dose-dependent effects; at **moderate doses (5-10 mcg/kg/min)**, it stimulates **beta-1 adrenergic receptors** in the heart - This beta-1 stimulation leads to increased **myocardial contractility** and **heart rate**, thus exerting a **positive inotropic effect** - This is a well-established therapeutic effect of dopamine *Improves renal perfusion* (TRUE Statement) - At **low doses (0.5-3 mcg/kg/min)**, dopamine selectively activates **dopamine-1 (D1) receptors** in the renal vasculature - This activation causes **renal vasodilation**, leading to increased **renal blood flow**, improved **glomerular filtration rate**, and enhanced **sodium excretion** - This "renal dose" effect is a classic pharmacological property of dopamine *Causes Vasoconstriction* (TRUE Statement) - At **high doses (>10 mcg/kg/min)**, dopamine primarily stimulates **alpha-1 adrenergic receptors** - This leads to generalized **vasoconstriction**, increasing **systemic vascular resistance** and **blood pressure** - This dose-dependent alpha effect is well-documented

Q: Which of the following is a centrally acting antihypertensive drug?

Methyldopa. ***Methyldopa*** - **Methyldopa** is a **prodrug** that is converted to **alpha-methylnorepinephrine** in the brain, which then stimulates **alpha-2 adrenergic receptors** in the brainstem. - This stimulation reduces **sympathetic outflow** from the central nervous system, leading to decreased heart rate, stroke volume, and peripheral vascular resistance, thus lowering blood pressure. *Phenoxybenzamine* - **Phenoxybenzamine** is an **alpha-1 and alpha-2 adrenergic receptor antagonist** (non-selective alpha blocker) that primarily acts peripherally. - It causes **vasodilation** by blocking alpha-1 receptors on smooth muscle, which reduces peripheral vascular resistance. *Propranolol* - **Propranolol** is a **non-selective beta-blocker** that primarily acts on peripheral beta-adrenergic receptors. - It reduces heart rate and cardiac output by blocking **beta-1 receptors** in the heart and can also affect beta-2 receptors in the lungs and vasculature. *Prazosin* - **Prazosin** is a **selective alpha-1 adrenergic receptor antagonist** that acts primarily on peripheral blood vessels. - It causes **vasodilation** in both arteries and veins by blocking alpha-1 receptors, which reduces both preload and afterload, lowering blood pressure.

Q: Which of the following statements about Conivaptan is correct?

It is a vasopressin antagonist.. ***It is a vasopressin antagonist.*** * **Conivaptan** is a non-peptide, dual **vasopressin V1A and V2 receptor antagonist**, meaning it blocks the action of vasopressin. * By blocking vasopressin, it promotes **aquaresis** (excretion of solute-free water), which is beneficial in conditions like **hyponatremia**. * *It selectively acts on V2 receptors.* * **Conivaptan** is a **dual antagonist**, blocking both **V1A and V2 receptors**, not just V2. * **Tolvaptan**, in contrast, is a selective **V2 receptor antagonist**. * *It is administered orally.* * **Conivaptan** is typically administered intravenously, particularly in hospital settings for acute hyponatremia. * **Tolvaptan** is the orally administered vasopressin antagonist. * *All of the options.* * Since Conivaptan is not selectively acting on V2 receptors and is not administered orally, this option is incorrect.

Q: Which of the following potassium-sparing diuretics was the first to be shown to reduce cardiac mortality in chronic heart failure patients?

Spironolactone. ***Spironolactone*** - **Spironolactone** was the first potassium-sparing diuretic shown to reduce **cardiac mortality** in patients with **chronic heart failure** in the **RALES trial** (Randomized Aldactone Evaluation Study). - Its beneficial effects in heart failure are primarily attributed to its **aldosterone receptor antagonist** properties, which counteract the harmful effects of aldosterone on the myocardium and vasculature, rather than just its diuretic effect. *Amiloride* - **Amiloride** is a potassium-sparing diuretic that works by directly inhibiting **epithelial sodium channels (ENaC)** in the collecting duct. - While it helps in potassium conservation, it has not been shown to significantly reduce cardiac mortality in chronic heart failure patients in clinical trials. *Triamterene* - **Triamterene** is another potassium-sparing diuretic that also directly inhibits **ENaC** in the collecting duct, similar to amiloride. - Like amiloride, it is used to prevent hypokalemia but lacks evidence for significant **cardiac mortality reduction** in chronic heart failure. *Eplerenone* - **Eplerenone** is a selective **aldosterone receptor antagonist**, similar to spironolactone, with fewer hormonal side effects. - While it has been shown to reduce **cardiac mortality** in chronic heart failure (e.g., in the EMPHASIS-HF trial), it was introduced later than spironolactone and was not the *first* to demonstrate this benefit.

Question 1

Most common site for medulloblastoma is-

Accepted Answer

Cerebellum

Answer

Pituitary

Answer

Cerebrum

Answer

Pineal gland

Question 2

Orphan Annie nuclei are characteristic of which of the following?

Accepted Answer

Papillary thyroid carcinoma

Answer

Paraganglioma with Zellballen pattern

Answer

Meningioma with psammoma bodies

Answer

Pituitary adenoma with atypical nuclei

Question 3

Which of the following is the most likely proliferating breast mass?

Accepted Answer

Fibroadenoma

Answer

Duct ectasia

Answer

Adenosis

Answer

Papilloma

Question 4

ER positive status in carcinoma breast indicates?

Accepted Answer

Prognosis

Answer

Etiology

Answer

Site

Answer

None of the options

Question 5

Which gene mutation is commonly associated with malignant melanoma?

Accepted Answer

CDKN2A

Answer

MYCN

Answer

RET

Answer

BRAF

Question 6

Which of the following best describes a Type B adverse drug reaction?

Accepted Answer

Unpredictable bizarre reaction

Answer

Augmented effect of drug

Answer

Effect seen on chronic use of drug

Answer

Delayed effect of drug

Question 7

Which of the following statements about dopamine is false?

Accepted Answer

Causes increase in GI Ischemia

Answer

Improves renal perfusion

Answer

Causes Vasoconstriction

Answer

Positive ionotropic

Question 8

Which of the following is a centrally acting antihypertensive drug?

Accepted Answer

Methyldopa

Answer

Phenoxybenzamine

Answer

Propranolol

Answer

Prazosin

Question 9

Which of the following statements about Conivaptan is correct?

Accepted Answer

It is a vasopressin antagonist.

Answer

It selectively acts on V2 receptors.

Answer

It is administered orally.

Answer

All of the options.

Question 10

Which of the following potassium-sparing diuretics was the first to be shown to reduce cardiac mortality in chronic heart failure patients?

Accepted Answer

Spironolactone

Answer

Amiloride

Answer

Triamterene

Answer

Eplerenone

NEET-PG 2012

Anatomy

Pathology

Pharmacology