anaplastic large cell lymphoma

Definition: Anaplastic large cell lymphoma is a T-cell lymphoma that accounts for only 3% of all non-Hodgkin lymphomas.

Images

 Anaplastic large cell lymphoma, CD30 positive, ALK negative

• https://twitter.com/BellaMicheleang/status/766173457554038784

 Primary cutaneous anaplastic large cell lymphoma - large atypical cells with mitosis, ALK negative.

• https://twitter.com/JJSpeiserMD/status/742413791825137665

Digital cases

 HPC:81 : ALK- anaplastic large cell lymphoma of bone
 HPC:341 : ALK- anaplastic large cell lymphoma of bone
 JRC:2892 : Anaplastic large cell lymphoma (ALCL)

CD30 positive anaplastic large cell lymphoma expresses pan T cell markers, or less commonly is a null (neither B nor T cell) phenotype.

ALK positivity is more common in children and confers a better prognosis. It is present in about 65% of systemic cases. The t(2;5) translocation confers ALK positivity. ALK on chromosome 2 fuses with NPM on chromosome 5.

It shows two forms:
 1) systemic type
 2) cutaneous type.

• The cutaneous type is more common in adults.
• CD30 positive anaplastic large cell lymphoma usually shows a T cell phenotype, and are less commonly a null phenotype.

Types

 according to CD30

• CD30+ anaplastic large cell lymphoma
• CD30- anaplastic large cell lymphoma

 according to ALK

• ALK+ anaplastic large cell lymphoma
• ALK- anaplastic large cell lymphoma

Associations

 Epstein-Barr virus infection following cardiac transplantion (15104308)
 breast implant capsule (18594466)

 lymphomatoid papulosis

• Lymphomatoid papulosis is a chronic, recurrent, self-healing papulonodular skin rash with features of a CD30+ malignant T cell lymphoma.
• The prognosis is good, but patients have an increased risk of developing a cutaneous or nodal lymphoma, such as primary cutaneous anaplastic large cell lymphoma, mycosis fungoides, and Hodgkin’s lymphoma.

Differential diagnosis

 classic Hodgkin lymphoma
 CD30+ DLBCL and anaplastic DLBCL
 KSHV/HHV8-associated lymphoma (15105661)

Open references

 Discovery of recurrent t(6;7)(p25.3;q32.3) translocations in ALK-negative anaplastic large cell lymphomas by massively parallel genomic sequencing. Feldman AL, Dogan A, Smith DI, Law ME, Ansell SM, Johnson SH, Porcher JC, Ozsan N, Wieben ED, Ecklof0f BW, Vasmatzis G. Blood. 2011 Jan 20;117(3):915-9. doi : 10.1182/blood-2010-08-303305 PMID: 21030553 [Free]

References

 Ozdemirli M, Cheson B, Jaffe ES.What is anaplastic large cell lymphoma?Am J Surg Pathol. 2004 Dec;28(12):1664-5; PMID: 15577690