Veterinary Society of
Surgical Oncology

CUTANEOUS LYMPHOSARCOMA

General Considerations

  • B cell or mixed cutaneous LSA that can either be primary or multicentric LSA
  • no breed or site predilection
  • single or multiple lesions with plaque, pustule, or ulcerative skin disease and resultant pruritis
  • nodules with thick crust and underlying ulceration and erythematous rim

Treatment

  • surgical resection ± systemic chemotherapy

Prognosis

  • response to chemotherapy is usually poorer than multicentric LSA
  • mycosis fungoides and cutaneous LSA in cats is associated with very poor prognosis as response to therapy is rare

MYCOSIS FUNGOIDES

General Considerations

  • T cell cutaneous LSA
  • breed predisposition: Poodle and Cocker Spaniel
  • mycosis fungoides has been reported in cats
  • site: epidermis, superficial dermis, and periadnexa (= epidermotrophic)
  • gross appearance: plaque or nodular lesion

Clinical Signs

  • protracted clinical course with 3 clinical stages:
  • premycotic (erythroderma) stage: eczema, erythema, pigmentation or depigmentation, telangiectasis, atrophy, alopecia, and variable pruritis with trunk or neck involvement initially ± primary mucocutaneous junction or entire body involvement
  • mycotic (plaque) stage: erythematous, raised, thickened, and firm plaques that may be ulcerative and exudative
  • tumor stage: proliferative, protruding nodules ± ulceration and metastasis to regional lymph nodes and internal organs
  • secondary pyodermas and lymphadenomegaly secondary to chronic dermatitis is common

Sezary Syndrome

  • leukemic variant of mycosis fungoides characterized by circulating malignant helper T cells
  • mycosis fungoides complicated by Sezary syndrome is characterized by splenomegaly, lymphadenopathy, and cyclic episodes of generalized erythroderma
  • Sezary cells are identified in the peripheral blood of 100% of humans in the premycotic stage and 40% of the mycotic and tumor stages
  • bone marrow does not become infiltrated with neoplastic cells in either mycosis fungoides or Sezary syndrome

Diagnosis

  • biopsy although premycotic and mycotic stages are more reliable than tumor stage

Treatment

  • no uniform success with multiple treatment regimens
  • lesions limited to the skin can be treated with:
  • topical nitrogen mustards (i.e., mechiorethamine or BCNU)
  • vitamin A analogues (i.e., 13-cis-retinoic acid)
  • electron radiation therapy
  • photodynamic therapy (with psoralen UVA)
  • intravenous and intralesional fibronectin (acts as opsonin in areas of disrupted tissue and chemotactically draws macrophages into tissue)
  • intradermal placental lysate
  • prednisone
  • systemic chemotherapy should be attempted with disseminated mycosis fungoides but results are usually poor

Prognosis

  • poor with most animals euthanased prior to tumor stage development due to uncontrollable skin lesions

CUTANEOUS LYMPHOSARCOMA

Back to top