Anaplastic large cell lymphoma

From Libre Pathology
Jump to navigation Jump to search

Anaplastic large cell lymphoma, abbreviated ALCL, is an uncommon large cell lymphoma.

Anaplastic large cell lymphoma
Diagnosis in short

Anaplastic large cell lymphoma. H&E stain.

LM large cells with eosinophilic cytoplasm, Hallmark cells ("horseshoe-shaped or donut-shaped nucleus + eosinophilic paranuclear region")
LM DDx Hodgkin's lymphoma, poorly differentiated carcinoma
IHC CD30 +ve, ALK-1 -ve/+ve, CD45 +ve, CD4 +ve, CD3 -ve/+ve, CD7 -ve/+ve, EMA +ve
Molecular t(2,5)(p23;q35)
Site skin, lymph node, other

Prevalence uncommon
Prognosis good to poor, dependent on ALK status and site

General

  • May look a lot like a carcinoma.
    • Often subcapsular in LNs.
  • Usually T-cell derived.
  • May be isolated to the skin - good prognosis.

Subtypes:

  • Systemic ALCL.
  • Cutaneous ALCL -- ALK -ve.

ALK IHC - systemic form:

  • +ve = good prognosis (generally a disease of children, teenagers and young adults)
  • -ve = bad prognosis

Microscopic

Features:

  • Large cells with eosinophilic cytoplasm.
  • Usually appear cohesive.
  • May be subcapsular in a lymph node and mimic a carcinoma.
  • Hallmark cells = "horseshoe-shaped or donut-shaped nucleus + eosinophilic paranuclear region"[1][2] - key feature.
    • The donut-shaped version is also known as a "wreath cell"[3] - large (multi-nucleated) cells with (morphologically) one toroidal-shaped nucleus.
  • ALK+ ALCL includes variants without the classical hallmark cells, e.g. small cell variant and lymphohistiocytic variant

DDx:

  • Hodgkin's lymphoma
  • Anaplastic variants of other haematolymphoid malignancies, e.g. DLBCL or myeloma
  • Carcinoma
  • Melanoma

Images

www:

IHC

Features:

  • CD30 +ve (usually strong and diffuse)
  • ALK-1 -ve/+ve; strongly supports ALCL Dx if +ve.
  • CD45 +ve.
  • CD4 +ve.
  • CD3 -ve/+ve.
  • CD7 -ve/+ve.
  • EMA +ve.
  • Cytotoxic markers (e.g. TIA, perforin)

Molecular

  • In ALK+ ALCL, there is commonly an ALK1 rearrangement.
    • This may be ALK::NPM1, i.e. t(2,5)(p23;q35)[4] - combined nuclear and cytoplasmic ALK staining is a surrogate for this translocation.
  • Other non-NPM1 partners may occur. A ALK1 break-apart probe will detect these.

See also

References

  1. Rapkiewicz, A.; Wen, H.; Sen, F.; Das, K. (Dec 2007). "Cytomorphologic examination of anaplastic large cell lymphoma by fine-needle aspiration cytology.". Cancer 111 (6): 499-507. doi:10.1002/cncr.23120. PMID 17941004. http://onlinelibrary.wiley.com/doi/10.1002/cncr.23120/full.
  2. Ponzoni, M.; Terreni, MR.; Ciceri, F.; Ferreri, AJ.; Gerevini, S.; Anzalone, N.; Valle, M.; Pizzolito, S. et al. (Nov 2002). "Primary brain CD30+ ALK1+ anaplastic large cell lymphoma ('ALKoma'): the first case with a combination of 'not common' variants.". Ann Oncol 13 (11): 1827-32. PMID 12419758.
  3. Amin, HM.; Lai, R. (Oct 2007). "Pathobiology of ALK+ anaplastic large-cell lymphoma.". Blood 110 (7): 2259-67. doi:10.1182/blood-2007-04-060715. PMID 17519389. http://bloodjournal.hematologylibrary.org/content/110/7/2259.full.html.
  4. Lamant L, Meggetto F, al Saati T, et al. (January 1996). "High incidence of the t(2;5)(p23;q35) translocation in anaplastic large cell lymphoma and its lack of detection in Hodgkin's disease. Comparison of cytogenetic analysis, reverse transcriptase-polymerase chain reaction, and P-80 immunostaining". Blood 87 (1): 284–91. PMID 8547653.