Systemic Anaplastic Large Cell Lymphoma, ALK-Positive

**Semantic type:** Neoplastic Process

**Definition:** A T-cell peripheral lymphoma affecting multiple anatomic sites. It is composed of usually large, pleomorphic, CD30 positive T-lymphocytes with abundant cytoplasm. It is characterized by the presence of a translocation involving the ALK gene and expression of ALK fusion protein.

**Synonyms:** - Primary Systemic ALK-Positive ALCL - Primary Systemic ALK-Positive Anaplastic Large Cell Lymphoma - Primary Systemic ALKoma - Primary Systemic Anaplastic Large Cell Lymphoma, ALK-Positive