UPSC-CMS 2013 — Pathology

Q: Pancreatic calculi are composed of :

Calcium carbonate. ***Calcium carbonate*** - Pancreatic calculi are predominantly composed of **calcium carbonate (70-90%)**, which precipitates around a protein-rich nidus [1]. - This occurs in **chronic calcific pancreatitis**, where altered pancreatic juice composition leads to calcium salt precipitation and stone formation [1], [2]. - The stones are radiopaque and can be seen on plain radiography, helping in diagnosis. *Calcium phosphate* - While **calcium phosphate** may be present in small amounts in pancreatic stones, it is **not the primary component**. - Calcium phosphate is more commonly associated with certain types of urinary calculi. *Calcium oxalate* - **Calcium oxalate** is the most common component of **renal (kidney) stones**, not pancreatic stones. - Kidney stone formation is influenced by factors like dietary oxalate, hydration status, and urinary pH, distinct from pancreatic pathophysiology. *Calcium bilirubinate* - **Calcium bilirubinate** is a major component of **pigment gallstones**, particularly black pigment stones formed in the gallbladder. - These stones are associated with conditions like chronic hemolysis, cirrhosis, or biliary infections, and are entirely distinct from pancreatic calculi. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 407-408. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Pancreas, pp. 893-895. [Practice more Pathology PYQs on OnCourse]

Q: Out of the following, select the histologic type of endometrial cancer which has the worst prognosis:

Papillary serous carcinoma. ***Papillary serous carcinoma*** - This subtype is considered a **Type II endometrial cancer**, which is often **aggressive**, poorly differentiated, and has a high metastatic potential. [1] - It frequently presents at an advanced stage and has a **poor prognosis** due to its rapid growth and tendency for widespread peritoneal dissemination. [1] *Clear cell carcinoma* - While also a **Type II endometrial cancer** with an aggressive course, it generally has a slightly better prognosis than papillary serous carcinoma. - It is characterized by polygonal cells with **clear cytoplasm** and often presents with more localized disease compared to serous carcinoma. *Mucinous adenocarcinoma* - This is typically classified as a **Type I endometrial cancer**, which is low-grade and generally associated with a **favorable prognosis**. [1] - It is characterized by cells producing **mucin**, often resembling endocervical adenocarcinoma. *Well differentiated endometrioid adenocarcinoma* - This is the **most common type of endometrial cancer** and is typically a **Type I cancer**, associated with a very **good prognosis**. [1] - It is characterized by glandular differentiation that closely resembles normal endometrial glands, driven by unopposed estrogen exposure. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Female Genital Tract, pp. 1021-1024. [Practice more Pathology PYQs on OnCourse]

3 Previous Year Questions with Answers & Explanations

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All Subjects Anatomy (4)Community Medicine (23)Forensic Medicine (1)Internal Medicine (8)Microbiology (1)Obstetrics and Gynecology (31)Ophthalmology (1)Orthopaedics (3)Pathology (3)Pediatrics (2)Pharmacology (7)Physiology (5)Psychiatry (1)Radiology (1)Surgery (17)

Pancreatic calculi are composed of :

Out of the following, select the histologic type of endometrial cancer which has the worst prognosis:

Autosomal recessive disorders include all except :

UPSC-CMS 2013 - Pathology UPSC-CMS Practice Questions and MCQs

Question 1: Pancreatic calculi are composed of :

A. Calcium carbonate (Correct Answer)
B. Calcium phosphate
C. Calcium oxalate
D. Calcium bilirubinate

Explanation: ***Calcium carbonate*** - Pancreatic calculi are predominantly composed of **calcium carbonate (70-90%)**, which precipitates around a protein-rich nidus [1]. - This occurs in **chronic calcific pancreatitis**, where altered pancreatic juice composition leads to calcium salt precipitation and stone formation [1], [2]. - The stones are radiopaque and can be seen on plain radiography, helping in diagnosis. *Calcium phosphate* - While **calcium phosphate** may be present in small amounts in pancreatic stones, it is **not the primary component**. - Calcium phosphate is more commonly associated with certain types of urinary calculi. *Calcium oxalate* - **Calcium oxalate** is the most common component of **renal (kidney) stones**, not pancreatic stones. - Kidney stone formation is influenced by factors like dietary oxalate, hydration status, and urinary pH, distinct from pancreatic pathophysiology. *Calcium bilirubinate* - **Calcium bilirubinate** is a major component of **pigment gallstones**, particularly black pigment stones formed in the gallbladder. - These stones are associated with conditions like chronic hemolysis, cirrhosis, or biliary infections, and are entirely distinct from pancreatic calculi. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 407-408. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Pancreas, pp. 893-895.

Question 2: Out of the following, select the histologic type of endometrial cancer which has the worst prognosis:

A. Clear cell carcinoma
B. Papillary serous carcinoma (Correct Answer)
C. Mucinous adenocarcinoma
D. Well differentiated endometrioid adenocarcinoma

Explanation: ***Papillary serous carcinoma*** - This subtype is considered a **Type II endometrial cancer**, which is often **aggressive**, poorly differentiated, and has a high metastatic potential. [1] - It frequently presents at an advanced stage and has a **poor prognosis** due to its rapid growth and tendency for widespread peritoneal dissemination. [1] *Clear cell carcinoma* - While also a **Type II endometrial cancer** with an aggressive course, it generally has a slightly better prognosis than papillary serous carcinoma. - It is characterized by polygonal cells with **clear cytoplasm** and often presents with more localized disease compared to serous carcinoma. *Mucinous adenocarcinoma* - This is typically classified as a **Type I endometrial cancer**, which is low-grade and generally associated with a **favorable prognosis**. [1] - It is characterized by cells producing **mucin**, often resembling endocervical adenocarcinoma. *Well differentiated endometrioid adenocarcinoma* - This is the **most common type of endometrial cancer** and is typically a **Type I cancer**, associated with a very **good prognosis**. [1] - It is characterized by glandular differentiation that closely resembles normal endometrial glands, driven by unopposed estrogen exposure. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Female Genital Tract, pp. 1021-1024.

Question 3: Autosomal recessive disorders include all except :

A. Hirschsprung disease
B. Retinoblastoma (Correct Answer)
C. Albinism
D. Sickle cell anaemia

Explanation: ***Retinoblastoma*** - Retinoblastoma is the correct answer because it is **NOT an autosomal recessive disorder**. - It follows **autosomal dominant** inheritance in hereditary cases (~40%), where a germline mutation in the RB1 gene is inherited. - Sporadic cases (~60%) result from somatic mutations in both RB1 alleles. - The **two-hit hypothesis** explains tumor development: both copies of the tumor suppressor RB1 gene must be inactivated. *Hirschsprung disease* - Hirschsprung disease has **complex multifactorial inheritance**, not autosomal recessive. - It involves multiple genes (RET, EDNRB, EDN3) with **incomplete penetrance and variable expressivity**. - However, it is not classified as a classic autosomal recessive disorder, making it technically debatable. - Characterized by **absence of ganglion cells** in the distal colon causing functional obstruction. *Albinism* - Oculocutaneous albinism (OCA types 1-4) is a classic **autosomal recessive** disorder [2]. - Results from mutations in genes involved in **melanin biosynthesis** (TYR, OCA2, TYRP1, SLC45A2) [2]. - Leads to reduced or absent pigmentation in skin, hair, and eyes [2]. *Sickle cell anaemia* - Sickle cell anemia is a well-established **autosomal recessive** hemoglobinopathy [1], [3]. - Caused by a point mutation (Glu6Val) in the **HBB gene** encoding beta-globin [3]. - Results in production of hemoglobin S (HbS), causing RBC sickling under hypoxic conditions [3]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Genetic Disorders, pp. 150-151. [2] 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. 119-120. [3] 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. 93-94.