## **Core Concept**
Mantle cell lymphoma (MCL) is a type of B-cell lymphoma characterized by a specific chromosomal translocation. This translocation involves the immunoglobulin heavy chain gene and a cyclin-dependent kinase regulator. Understanding this genetic abnormality is crucial for diagnosing and managing MCL.

## **Why the Correct Answer is Right**
The correct answer, , refers to the chromosomal translocation t(11;14)(q13;q32). This translocation juxtaposes the **cyclin D1** gene (CCND1) on chromosome 11 with the **immunoglobulin heavy chain** (IgH) gene on chromosome 14. As a result, the cyclin D1 gene is overexpressed, leading to uncontrolled cell proliferation and the development of lymphoma. The t(11;14) translocation is a hallmark genetic feature of mantle cell lymphoma.

## **Why Each Wrong Option is Incorrect**
- **Option A:** . This option is incorrect because while t(8;14) is a significant translocation in Burkitt lymphoma, it involves the MYC gene and the immunoglobulin heavy chain gene, not cyclin D1.
- **Option B:** . This option is incorrect because t(14;18) is commonly associated with follicular lymphoma, involving the BCL2 gene and the immunoglobulin heavy chain gene.
- **Option D:** . This option is incorrect because t(2;5) is associated with anaplastic large cell lymphoma, involving the ALK gene and the NPM gene.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that the diagnosis of mantle cell lymphoma can be confirmed by the detection of the t(11;14) translocation, often through **fluorescence in situ hybridization (FISH)** or **PCR** for the IgH-CCND1 fusion. Additionally, the overexpression of cyclin D1 is a diagnostic hallmark, and **cyclin D1 immunohistochemistry** is commonly used to support the diagnosis.

## **Correct Answer:** . t(11;14)