Synopsis

 2%-7% of non-Hodgkin lymphomas

Immunochemistry

 CD30+
 EMA+ (50%)
 P53+

Variants

 monomorphic ALCL
 small cell ALCL
 lymphohistiocytic ALCL
 Hodgkin-like ALCL
 sarcomatoid ALCL
 neutrophil-rich ALCL
 eosinophil-rich ALCL
 signet-ring ALCL

Associations

 HIV infection

Differential diagnosis

 classic Hodgkin lymphoma

• syncitial variant of sclerosing nodular Hodgkin lymphoma
• lymphocyte depletion Hodkgkin lymphoma

 sinusoidal CD30-positive large B-cell lymphoma (#10757332#)
 HHV-8-associated lymphoma (#15105661#)
 Carcinomas
 melanoma

Molecular biology

 fusion genes invoving the ALK gene

• NPM1/ALK fusion protein (70-80%) by t(2;5)(p23;q35)
• TPM3/ALK fusion protein (20%) by t(1;2)(q25;p23)
• MSN/ALK fusion protein by t(X;22)(q11;p23)
• ATIC/ALK fusion protein by inv(2)(p23q35)
• TFG/ALK fusion protein by t(2;3)(p23;q21)
• CLTC/ALK fusion protein by t(2;17)(p23;q23)
• ALO17/ALK fusion protein by t(2;17)(p23;q25)
• MYH9/ALK fusion protein t(2;22)(p23;q11.2)

See also

 cutaneous CD30+ anaplastic large-cell lymphoma (cutaneous CD30+ ALCL)