ALK-positive Large B Cell Lymphoma

Question 1

What is the definition of ALK positive large B cell lymphoma ?

Answer 1

• aggressive neoplasm with ALK positivity
• monomorphic, large immunoblast like B cells
• usually have a plasma cell phenotype

Question 2

What is the epidemiology of ALK + Large B cell lymphoma?

Answer 2

• very rare lymphoma
• more common in young men —> M:F 5:1
• spans all ages with 1/3 of cases in pediatric patients
  IMP
  
  • no association with immunosuppression

Question 3

What sites are typically involved with ALK positive Large B cell lymphoma ?

Answer 3

• mediastinal mass or involves the lymph nodes
• extranodal involvement has also been identified
  
  • nasopharyngeal, tongue, stomach, bone, soft tissue liver, spleen and skin

Question 4

What is the clinical presentation ?

Answer 4

• generalized lymphadenopathy
• 60% present with advanced stage disease
• bone marrow is involved in 25% of cases