NEET-PG 2012 — Pathology
69 Previous Year Questions with Answers & Explanations
Malignancy in pheochromocytoma is indicated by:
Renal papillary necrosis is almost always associated with one of the following conditions:
What is the histological appearance of the brain in Creutzfeldt-Jakob disease?
Thorium-induced tumor is which of the following?
Transitional cell carcinoma of the bladder is associated with which of the following?
What laboratory findings are associated with common variable hypogammaglobulinemia?
Li–Fraumeni syndrome is associated with mutations in which of the following genes?
All of the following statements about Giant cell arteritis are true except?
What type of anaemia is primarily associated with leukaemia?
Which of the following is not typically seen in Disseminated Intravascular Coagulation (DIC)?
NEET-PG 2012 - Pathology NEET-PG Practice Questions and MCQs
Question 1: Malignancy in pheochromocytoma is indicated by:
- A. Mitotic figures
- B. Capsular invasion
- C. Metastasis (Correct Answer)
- D. Vascular invasion
Explanation: ***Metastasis*** - The definitive criterion for diagnosing **malignancy in pheochromocytoma** is the presence of **metastatic disease**, meaning tumor cells have spread to sites where chromaffin tissue is not normally found. - The distinction between benign and malignant pheochromocytomas often cannot be made based on histological features alone. *Mitotic figures* - While increased **mitotic activity** can be a feature indicating aggressive tumor behavior, it is not a standalone definitive criterion for malignancy in pheochromocytoma. - Benign pheochromocytomas can occasionally show mitotic figures, and their presence alone does not confirm malignancy. *Capsular invasion* - **Capsular invasion** suggests an aggressive tumor but is not a definitive indicator of malignancy in pheochromocytoma. - Tumors that exhibit capsular invasion without distant spread are still considered to have uncertain malignant potential rather than overt malignancy. *Vascular invasion* - Similar to capsular invasion, **vascular invasion** indicates an increased risk of metastasis but is not a conclusive sign of malignancy. - The presence of tumor cells within blood vessels raises suspicion, but true malignancy is only confirmed by the presence of distant metastases.
Question 2: Renal papillary necrosis is almost always associated with one of the following conditions:
- A. Diabetes-mellitus
- B. Analgesic-nephropathy (Correct Answer)
- C. Chronic pyelonephritis
- D. Post streptococcal GN
Explanation: ***Analgesic-nephropathy*** - Chronic use of certain analgesics (especially **phenacetin**, aspirin, and NSAIDs) can lead to **ischemia** and damage to the renal papillae, causing **papillary necrosis**. - This condition is considered the **classic** cause of renal papillary necrosis and is the most frequently emphasized in medical education. - Analgesic nephropathy shows a very **strong and direct association** with papillary necrosis as a hallmark feature. *Diabetes-mellitus* - **Diabetes mellitus** is actually one of the **most common causes** of renal papillary necrosis in clinical practice, particularly when complicated by **infection** or **ischemia** [1]. - While clinically very common, it causes papillary necrosis through multiple mechanisms and is often associated with coexisting factors like **pyelonephritis** [1], [2] or NSAID use. - In the context of "almost always associated," analgesic nephropathy has a more direct and consistent association. *Chronic pyelonephritis* - **Chronic pyelonephritis** involves recurrent bacterial infections of the kidney parenchyma and can lead to scarring and kidney damage. - While it is indeed a recognized cause of **papillary necrosis** (part of the POSTCARDS mnemonic), it is not as consistently associated as analgesic nephropathy [2]. *Post streptococcal GN* - **Post-streptococcal glomerulonephritis (PSGN)** is an immune-mediated inflammatory kidney disease that typically follows a **streptococcal infection**. - It primarily affects the **glomeruli** and does **not** cause necrosis of the renal papillae, making this option incorrect. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 543-544. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 937-940.
Question 3: What is the histological appearance of the brain in Creutzfeldt-Jakob disease?
- A. Neuronophagia
- B. Micro abscess
- C. Demyelination
- D. Spongiform changes (Correct Answer)
Explanation: ***Spongiform changes*** - The hallmark histological feature of **Creutzfeldt-Jakob disease (CJD)** is **spongiform degeneration**, characterized by vacuolation of neuronal cell bodies [1]. - It results in a **spongy appearance** of the affected brain regions, particularly in the **cerebral cortex** and **basal ganglia** [1]. *Neuronophagia (can occur in various contexts, not specific to CJD)* - Neuronophagia refers to the phagocytic activity involving **dying neurons**, which can occur in various conditions but is not a defining feature of CJD [2]. - It indicates the presence of **inflammation** or a response to neuronal injury rather than specific changes seen in CJD. *Demyelination (associated with multiple sclerosis)* - Demyelination is primarily associated with conditions like **multiple sclerosis** and is characterized by loss of **myelin sheaths** around neurons. - This is not related to CJD, which involves **prion protein accumulation** and subsequent neuronal degeneration. *Micro abscess (indicative of bacterial infections)* - Micro abscesses indicate localized collections of **pus** typically seen in **bacterial infections**, which is incongruent with the pathophysiology of CJD. - In CJD, there are no signs of **inflammation** or **neutrophilic infiltration** associated with abscess formation [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1284-1286. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Peripheral Nerves and Skeletal Muscles, pp. 1255-1256.
Question 4: Thorium-induced tumor is which of the following?
- A. Angiosarcoma of liver (Correct Answer)
- B. Lymphoma
- C. Renal cell carcinoma
- D. Astrocytoma
Explanation: ***Angiosarcoma of liver*** - Thorium exposure is specifically linked to the development of **angiosarcoma of the liver**, often seen in individuals with a history of thorium dioxide injection [1]. - This type of tumor arises from **vascular endothelial cells** and is highly aggressive, often leading to significant morbidity. *Lymphoma* - Lymphoma is associated with **immune system factors** and typically arises from lymphoid tissues, which do not correlate with thorium exposure. - **Hematological malignancies** such as lymphoma do not have a documented direct association with thorium as a causative agent. *Astrocytoma* - Astrocytomas originate from **glial cells** in the brain and are primarily influenced by genetic predispositions rather than environmental carcinogens like thorium. - There is no established relationship between **thorium exposure** and the incidence of brain tumors such as astrocytomas. *Renal cell carcinoma* - Renal cell carcinoma is commonly linked to **smoking, obesity**, and genetic factors rather than thorium exposure. - It does not have a recognized connection to thorium, which is more specifically associated with liver tumors. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 216-217.
Question 5: Transitional cell carcinoma of the bladder is associated with which of the following?
- A. Malaria
- B. Schistosomiasis
- C. None of the options (Correct Answer)
- D. Ascariasis
Explanation: ***Schistosomiasis*** - Schistosomiasis, particularly from *Schistosoma haematobium*, is a well-known risk factor for **transitional cell carcinoma of the bladder** due to chronic irritation and inflammation [1]. - The association arises due to the **presence of eggs in the bladder**, leading to calcification and eventually cancer development. *Malaria* - Malaria is primarily associated with **hemolytic anemia** and does not have a direct correlation with **bladder cancer**. - Its causative agents, *Plasmodium* species, do not typically lead to **urological malignancies** like transitional cell carcinoma. *Ascarasis* - Ascarasis, caused by *Ascaris lumbricoides*, primarily affects the **intestines** and is more associated with gastrointestinal issues. - There is no significant link between ascarasis and the **development of bladder cancer**. *Any of d above* - As this option suggests all listed conditions, it incorrectly implies that **malaria** and **ascarasis** are linked to bladder cancer, which they are not. - Transitional cell carcinoma is specifically associated with **schistosomiasis**, making this option misleading. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 968-970.
Question 6: What laboratory findings are associated with common variable hypogammaglobulinemia?
- A. Low serum immunoglobulin levels (Correct Answer)
- B. Decreased B cell count
- C. Increased B cell count
- D. Neutropenia
Explanation: ***Low serum immunoglobulin levels*** - **Common variable hypogammaglobulinemia (CVID)** is characterized by significantly **low levels of IgG, IgA, and/or IgM** due to impaired B cell differentiation into plasma cells. - This deficiency in antibodies is the hallmark of the disorder, explaining the increased susceptibility to infections. *Decreased B cell count* - While CVID involves impaired B cell function, the **B cell counts** in the peripheral blood are typically **normal** or sometimes even elevated [1]. - The problem lies in their inability to differentiate and produce adequate antibodies, not in their numerical presence [1]. *Increased B cell count* - An increased B cell count is not a characteristic finding in CVID; peripheral B cell numbers are usually normal [1]. - If B cell counts are significantly increased, other conditions such as certain **lymphoproliferative disorders** should be considered. *Neutropenia* - **Neutropenia** (low neutrophil count) is not a primary diagnostic feature of CVID, although it can occur in some patients with autoimmune complications. - The defining laboratory finding is the **deficiency of immunoglobulins**, leading to recurrent infections. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 249-250.
Question 7: Li–Fraumeni syndrome is associated with mutations in which of the following genes?
- A. Gene RB1
- B. Gene BRCA1
- C. Gene P21
- D. Gene TP53 (Correct Answer)
Explanation: ***Gene TP53*** - Li-Fraumeni syndrome is a rare, inherited cancer susceptibility syndrome associated with germline mutations in the **TP53 tumor suppressor gene**. - The **TP53 gene** encodes the p53 protein, which plays a critical role in cell cycle arrest, DNA repair, and initiation of apoptosis in response to cellular stress, thus preventing tumor formation. *Gene P21* - The **p21 gene** (CDKN1A) is a cyclin-dependent kinase inhibitor that acts downstream of p53, mediating p53-induced cell cycle arrest. - While p21 is involved in the p53 pathway, mutations in p21 itself are not the primary cause of Li-Fraumeni syndrome. *Gene RB1* - The **RB1 gene** encodes the retinoblastoma protein, a tumor suppressor involved in cell cycle regulation, particularly in controlling passage from G1 to S phase. - Mutations in **RB1** are primarily associated with hereditary retinoblastoma and osteosarcoma, not Li-Fraumeni syndrome. *Gene BRCA1* - The **BRCA1 gene** is a tumor suppressor gene involved in DNA repair, especially homologous recombination. - Germline mutations in **BRCA1** are strongly associated with hereditary breast and ovarian cancer syndrome, not Li-Fraumeni syndrome.
Question 8: All of the following statements about Giant cell arteritis are true except?
- A. Involves large to small sized arteries (Correct Answer)
- B. Granulomatous inflammation
- C. Segmental nature of the involvement
- D. Can involve the aorta and its major branches
Explanation: ***Involves large to small sized arteries*** - Giant cell arteritis (GCA) predominantly affects **medium to large-sized arteries**, most commonly the branches of the **carotid artery**, such as the temporal arteries [1]. - While it can affect various arteries, it does not typically involve **small-sized arteries**, such as arterioles, directly as a primary site of inflammation. *Granulomatous inflammation* - GCA is characterized histologically by **granulomatous inflammation** within the arterial wall, which includes multinucleated **giant cells** and lymphocytes [2]. - This specific inflammatory pattern is a hallmark feature used in the diagnosis of GCA upon biopsy [2]. *Segmental nature of the involvement* - The arterial inflammation in GCA is often **segmental**, meaning that affected arteries may have inflamed and non-inflamed sections alternating along their length [2]. - This segmental involvement often necessitates **longer biopsies** (e.g., 2-3 cm for temporal artery biopsy) to increase the diagnostic yield. *Can involve the aorta and its major branches* - GCA can indeed affect the **aorta** (aortitis) and its major branches, leading to complications like **aneurysms** or **dissections**. - Involvement of these larger vessels can manifest as symptoms such as **claudication** in the limbs or asymptomatic aneurysms detectable on imaging [1]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Osteoarticular And Connective Tissue Disease, pp. 688-689. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of Infancy and Childhood, pp. 516-517.
Question 9: What type of anaemia is primarily associated with leukaemia?
- A. Aplastic anaemia
- B. Iron deficiency anaemia
- C. Megaloblastic anaemia
- D. Myelophthisic anaemia (Correct Answer)
Explanation: ***Myelophthisic anaemia*** - This condition arises from the **displacement of normal hematopoietic tissue** in the bone marrow by abnormal cells, like those seen in leukaemia, leading to **extramedullary hematopoiesis**. - Marrow infiltration causes **pancytopenia** and often results in the presence of **immature granulocytes** and **nucleated red blood cells** in the peripheral blood (leukoerythroblastosis). *Iron deficiency anaemia* - This type of anaemia is caused by insufficient iron for **hemoglobin synthesis**, often due to chronic blood loss or inadequate dietary intake. - While leukaemia patients can develop iron deficiency due to bleeding, it is not the **primary type of anaemia** directly resulting from the marrow infiltration by leukaemic cells. *Megaloblastic anaemia* - Characterized by the production of abnormally large, immature red blood cells, primarily due to **vitamin B12** or **folate deficiency**. - There is no direct causal link between leukaemia and the development of megaloblastic anaemia as a **primary haemato-pathological mechanism**. *Aplastic anaemia* - Characterized by **pancytopenia** due to bone marrow failure with hypocellular marrow, not marrow infiltration. - While both leukaemia and aplastic anaemia can present with cytopenias, aplastic anaemia shows a **hypocellular marrow** whereas leukaemia shows a **hypercellular marrow** with infiltration by malignant cells.
Question 10: Which of the following is not typically seen in Disseminated Intravascular Coagulation (DIC)?
- A. Thrombocytopenia
- B. PT elevation
- C. Fibrinogen decreased
- D. Normal aPTT (Correct Answer)
Explanation: ***Normal APTT*** - In Disseminated Intravascular Coagulation (**DIC**), **APTT** is typically **prolonged** due to consumption of clotting factors [1]. - The presence of normal APTT indicates that coagulation pathways are not significantly affected, which is contrary to what is seen in DIC. *Fibrinogen decreased* - **Decreased fibrinogen levels** are common in DIC, reflecting its consumption during the coagulation process [1]. - This depletion is linked to the increased clotting and is a hallmark of DIC, making this statement false in the context of the question. *Thrombocytopenia* - **Thrombocytopenia** occurs in DIC as platelets are consumed during the formation of microclots [1]. - A significant drop in platelet count is a key feature of DIC, therefore this statement does not align with the "except" clause. *PT elevation* - Prothrombin Time (**PT**) is usually **elevated** in DIC due to the consumption of clotting factors [1]. - This reflects the ongoing activation of the coagulation cascade, supporting the exclusion in the question context. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 625-626.