Which is the most common subtype of classical Hodgkin lymphoma?
## **Core Concept**
Classical Hodgkin lymphoma (cHL) is a type of lymphoma characterized by the presence of **Reed-Sternberg cells** in the lymph nodes. It accounts for the majority of Hodgkin lymphoma cases and is distinct from nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) in terms of histopathology and clinical behavior. cHL is further subdivided into several subtypes.
## **Why the Correct Answer is Right**
The most common subtype of classical Hodgkin lymphoma is **nodular sclerosis Hodgkin lymphoma (NSHL)**, accounting for approximately 70% of cHL cases. NSHL is characterized by the presence of **Reed-Sternberg cells** and a nodular pattern of sclerosis (fibrosis) within the lymph node. This subtype often presents in young adults and has a relatively good prognosis.
## **Why Each Wrong Option is Incorrect**
- **Option A:** Lymphocyte-depleted Hodgkin lymphoma (LDHL) is a rare subtype of cHL, characterized by a paucity of lymphocytes and a high number of Reed-Sternberg cells. It tends to have a worse prognosis compared to NSHL.
- **Option B:** Mixed cellularity Hodgkin lymphoma (MCHL) is another subtype of cHL, which exhibits a mix of lymphocytes, eosinophils, neutrophils, and Reed-Sternberg cells. While it is more common than LDHL, it is less common than NSHL.
- **Option D:** Lymphocyte-predominant Hodgkin lymphoma (LPHL) or **nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL)** is a distinct entity from classical Hodgkin lymphoma, characterized by lymphocytic and histiocytic (or "popcorn") cells. It has a different immunophenotypic profile and clinical behavior compared to cHL.
## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that **nodular sclerosis Hodgkin lymphoma (NSHL) is often associated with a mediastinal mass** and has a predilection for young adults, particularly females. Recognizing the subtypes of Hodgkin lymphoma is crucial for understanding their distinct clinical features, prognoses, and treatment approaches.
## **Correct Answer:** . Nodular sclerosis Hodgkin lymphoma.