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Last reviewed: 15 Mar 2025
Last updated: 20 Sep 2024

Summary

Definition

History and exam

Key diagnostic factors

  • skin patches, plaques, or tumours
  • poikiloderma
  • erythroderma

Other diagnostic factors

  • pruritus
  • hypopigmented/hyperpigmented skin lesions
  • unilesional acral site involvement
  • lymphadenopathy
  • constitutional symptoms
  • palmar-plantar keratoderma
  • alopecia
  • leonine facies
  • onychodystrophy
  • hepatomegaly
  • ectropion
  • bullous, granulomatous, ichthyosiform, and purpuric lesions

Risk factors

  • age >50 years
  • male sex
  • black ethnicity (MF); white ethnicity (SS)
  • exposure to infectious agents
  • ultraviolet light exposure

Diagnostic investigations

1st investigations to order

  • FBC
  • skin biopsy
  • clonal T-cell receptor rearrangement
  • flow cytometry
  • comprehensive metabolic panel
  • LFTs
  • serum lactate dehydrogenase

Investigations to consider

  • screen for Sézary cells on blood film
  • human T-cell lymphotropic virus (HTLV)-I/2 serology
  • bone marrow biopsy
  • lymph node biopsy
  • CT scan or PET
  • HIV test

Treatment algorithm

Contributors

Authors

Robert A. Schwartz, MD, MPH

Professor and Head

Department of Dermatology

Rutgers New Jersey Medical School

Newark

NJ

Disclosures

RAS declares that he has no competing interests.

W. Clark Lambert, MD, PhD

Professor and Associate Head, Dermatology

Director, Dermatopathology

New Jersey Medical School

Newark

NJ

Disclosures

WCL declares he has no competing interests

Acknowledgements

Professor Robert A. Schwartz and Professor W. Clark Lambert would like to gratefully acknowledge Professor Tim M. Illidge, Dr Richard Cowan, and Dr Eileen Parry, previous contributors to this topic.

Disclosures

TMI, RC, and EP all declare that they have no competing interests.

Peer reviewers

Chris Kelsey, MD

Assistant Professor

Department of Radiation Oncology

Duke University School of Medicine

Durham

NC

Disclosures

CK declares that he has no competing interests.

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