Skin - Nonmelanocytic tumors
Lymphoma and related disorders
Mycosis fungoides

Author: Christopher Hale, M.D. (see Authors page)

Revised: 11 October 2016, last major update July 2012

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

PubMed search: mycosis fungoides [title] skin

Related topics: Premycotic (patch) stage, mycotic stage, tumorous stage

Cite this page: Mycosis fungoides. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/skintumornonmelanocyticmycosisfungoides.html. Accessed December 9th, 2016.
Definition / General
  • Most common primary cutaneous T cell lymphoma
  • Usually elderly or other adults
  • May arise from progression of large plaque psoriasis
  • Usually protracted clinical course over years
  • By definition, are negative for HIV1, HIV2, HTLV

  • Sézary syndrome:
    • Peripheral blood involvement by cerebroid cells with PAS+ granules, lymphadenopathy, diffuse erythema and scaling of entire body surface
    • Usually less epidermotropism
    • Lymph nodes may have tumor cells or dermatopathic lymphadenitis (no atypical T cells, normal architecture, no clonality)
  • Poor prognostic factors:
    • Generalized plaques / tumors, diffuse erythema, lymphadenopathy
    • 50% have nodal or visceral involvement that may resemble large cell lymphoma
    • Sepsis is a common terminal complication
  • Treatment for skin limited disease:
    • Total skin electron beam irradiation, topical chemotherapy, PUVA
Case Reports
Clinical Images
Images hosted on PathOut server:

Courtesy of Dr. Mark R. Wick:

Necrotizing

Various images

Transformed

Breast skin



Images hosted on other servers:

Erythematous plaques

Irregular erythematous patch

Micro Images
Images hosted on PathOut server:

Courtesy of Dr. Mark R. Wick:


Necrotizing

Necrotizing, CD30


Transformed


Breast skin

CD4



Images hosted on other servers:

H&E, CD45RO

Bullous lesions present

Molecular / Cytogenetics Description
  • Clonal proliferation of mature CD4+ epidermotropic lymphocytes
  • Low CD8 / CD3 ratio in epidermal tumor cells (Mod Pathol 2003;16:857)
Differential Diagnosis
  • Drug reaction
  • Inflammatory dermatoses (resemble early mycosis fungoides)