INI-CET 2021 - Pathology Practice Questions

Q: A boy presents with fever, night sweats, and neck swelling. The biopsy of swelling showed a starry sky appearance. What is the most likely genetic abnormality seen in this case?

MYC. ***MYC*** - The clinical presentation of **fever, night sweats, and neck swelling** in a child, coupled with a **starry sky appearance** on biopsy, is highly suggestive of **Burkitt lymphoma** [2, 3]. - **Burkitt lymphoma** is characterized by a **translocation involving the *MYC* gene** on chromosome 8, most commonly t(8;14), which leads to its overexpression and uncontrolled cell proliferation [1]. *RAS* - Mutations in the **RAS family of genes (HRAS, KRAS, NRAS)** are commonly found in a wide variety of cancers, including **leukemias, pancreatic cancer, and colorectal cancer**. - While *RAS* mutations drive proliferation, they are **not the primary genetic driver** of Burkitt lymphoma, nor are they linked to the characteristic starry sky appearance. *BCR-ABL* - The **BCR-ABL fusion gene**, resulting from the **Philadelphia chromosome (t(9;22))**, is the defining genetic abnormality of **chronic myeloid leukemia (CML)**. - CML presents with different symptoms and a distinct peripheral blood and bone marrow morphology, **not the "starry sky" appearance** seen in Burkitt lymphoma. *p53* - The **p53 tumor suppressor gene** is frequently mutated or inactivated in over half of all human cancers, leading to a loss of cell cycle control and apoptosis. - While **p53 mutations can occur in aggressive lymphomas**, including Burkitt lymphoma, the **primary and characteristic genetic abnormality** associated with Burkitt lymphoma and its presentation is the *MYC* translocation, not solely *p53* mutations. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 324-325. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 605-606. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 606.

Q: The graphical representation for flow cytometry analysis is done by which of the following?

Histogram, dot plot. ***Histogram, dot plot*** - **Histograms** are used in flow cytometry to display the distribution of a single parameter (e.g., cell size, fluorescence intensity) across the cell population. - **Dot plots** are used to visualize the relationship between two or more parameters, allowing for the identification of distinct cell populations based on multiple characteristics. *Pie chart, dot plot* - **Pie charts** are typically used to represent proportions of a whole, which is not the primary way flow cytometry data is presented for detailed cell analysis. - While dot plots are correct, the combination with pie charts makes this option less accurate for typical flow cytometry analysis. *Line diagram, dot plot* - **Line diagrams** are generally used to show trends over time or continuous relationships, which is not the standard graphical representation for direct flow cytometry output. - Although dot plots are used, the inclusion of line diagrams makes this option incorrect in the context of typical flow cytometry data visualization. *Bar diagram, dot plot* - **Bar diagrams** are often used for comparing discrete categories or counting occurrences, not for displaying continuous distributions or multi-parameter relationships in flow cytometry directly. - While dot plots are correct, the pairing with bar diagrams does not represent the common and most informative graphical methods for flow cytometry analysis.

Question 1

A 42 year-old female patient presents with cough, low-grade fever, and hemoptysis.
Investigations reveal a cavitary lesion on her right lung apex, which on biopsy reveals caseous necrosis. The underlying pathophysiology is:

Accepted Answer

Type 4 hypersensitivity reaction

Answer

Sudden cut off of blood supply

Answer

Enzyme degradation

Answer

Fibrinoid deposition

Question 2

A boy presents with fever, night sweats, and neck swelling. The biopsy of swelling showed a starry sky appearance. What is the most likely genetic abnormality seen in this case?

Accepted Answer

MYC

Answer

RAS

Answer

BCR-ABL

Answer

p53

Question 3

The graphical representation for flow cytometry analysis is done by which of the following?

Accepted Answer

Histogram, dot plot

Answer

Pie chart, dot plot

Answer

Line diagram, dot plot

Answer

Bar diagram, dot plot

Question 4

Fluorescence in situ hybridization (FISH) is required in which of the following interpretations of Her2/neu?

Accepted Answer

2+

Answer

All of the options

Answer

1+

Answer

3+

INI-CET 2021 — Pathology