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Lymphoma, Cutaneous 604.e5

Lymphoma, Cutaneous Client Education
Sheet
VetBooks.ir Acute General Treatment Diseases and Disorders

BASIC INFORMATION
• Variably sized subcutaneous nodules are char-
acteristic of nonepitheliotropic lymphoma. Canine epitheliotropic lymphoma:
Definition • In cats, plaquelike lesions are most common; • Oral differentiating agents
A malignant lymphoid neoplasm involving the nodules and erythroderma are also possible. ○ Vitamin A analogs (isotretinoin 1-3 mg/
skin or oral cavity Solitary lesions may occur initially, with kg PO q 24h): 45% remission rate for
additional lesions developing as the disease 5-15 months; caution regarding marked
Synonyms progresses. teratogenicity in animals and humans
Epitheliotropic lymphoma, mycosis fungoides • Topical agents
Etiology and Pathophysiology ○ Topical nitrogen mustard: anecdotal
Epidemiology Neoplastic lymphocytes in epitheliotropic response reported; use is not recommended
SPECIES, AGE, SEX lymphoma are T cells; CD8 phenotype most because of concern about human contact
• Uncommon in dogs; rare in cats common in dogs dermatitis and carcinogen exposure.
• Usually affects older animals • Radiation therapy
• No sex predisposition DIAGNOSIS ○ Total skin electron therapy may prove
beneficial; however, current limited
ASSOCIATED DISORDERS Diagnostic Overview availability precludes wide application.
Sézary syndrome, a concurrent tumor cell History and physical exam findings are non- ○ Other forms of radiation therapy may
population in peripheral blood specific but should lead to skin biopsy, which benefit patients with localized oral lesions
is diagnostic. or those with more generalized disease
Clinical Presentation needing palliation of specific discrete skin
DISEASE FORMS/SUBTYPES Differential Diagnosis lesions.
• Epitheliotropic lymphoma: more common • Immune-mediated disease (e.g., pemphigus • Chemotherapy: special handling requirements
form; lesions most commonly involve epi- vulgaris, bullous pemphigoid, discoid lupus and potentially severe or life-threatening
dermis, superficial dermis, and periadnexa; erythematosus, reactive histiocytic) adverse patient effects exist with many of
oral mucosal form also described; T-cell • Allergic skin disease with pyoderma these chemotherapeutic drugs; such concerns
origin; characteristic histologic feature is • Infectious disease (e.g., dermatophytosis) and rapid evolution of protocols warrant
Pautrier’s microabscesses (small aggregates consultation with/referral to an oncologist.
of epitheliotropic lymphoid tumor cells in Initial Database Chemotherapeutic drug options may include
epidermis); protracted clinical course • CBC, serum biochemistry panel, urinalysis: ○ CCNU (lomustine): 15%-30% complete
• Nonepitheliotropic lymphoma: uncommon; typically unremarkable. Occasionally, cir- remission (CR) rate and 50%-60% partial
subcutaneous nodules; B-cell origin; more culating lymphoblasts may be identified, remission (PR) rate for median duration
rapid onset and progression consistent with Sézary syndrome. of 3-4 months, or
• Skin biopsy: test of choice for establishing ○ Pegylated liposomal doxorubicin: 33% CR
HISTORY, CHIEF COMPLAINT definitive diagnosis rate and 11% PR rate for median of 2-3
• Epitheliotropic lymphoma may be divided months, or
2
into three stages: Advanced or Confirmatory Testing ○ Prednisone alone 20-40 mg/m PO q
○ Premycotic stage: erythematous lesions • Lymph node aspirate obtained for 24-48h: 25%-35% remission rate
with varying degrees of depigmentation cytologic evaluation to assess enlarged ○ Combination chemotherapy (p. 602) has
and alopecia over the trunk and neck, lymph nodes for lymphoma infiltration limited activity; response durations of 2-16
which may progress to other locations versus inflammation/reaction in severe weeks
○ Mycotic stage: erythematous, raised, firm dermatopathy • Surgery: may benefit patients with solitary
plaques, which may be ulcerated and • Thoracic radiographs to assess pulmonary resectable oral lesions
exudative infiltration, intrathoracic lymph node Canine nonepitheliotropic lymphoma:
○ Tumor stage: progressive thickening enlargement • Treat as for other forms of canine multicentric
and proliferation of plaque lesions with • Abdominal ultrasound to identify changes lymphoma.
ulceration; lymph node and/or other organ consistent with hepatic or splenic involve- Feline cutaneous lymphoma:
involvement possible ment, lymphadenopathy, or other sites of • Consider treatment as for canine epithelio-
• Nonepitheliotropic lymphoma in dogs pre- lymphoma tropic lymphoma.
sents as rapidly progressing and frequently • Bone marrow aspirate for cytologic evalua-
multiple subcutaneous nodules. tion to identify bone marrow involvement, Possible Complications
• Cutaneous lymphoma in cats presents as particularly in cases with suspected Sézary Adverse reactions to chemotherapy and the
progressive solitary or disseminated ulcer- syndrome COP protocol (cyclophosphamide, Oncovin,
ated plaques or nodules; oral involvement • Phenotyping (flow cytometry, polymerase and prednisone or prednisolone) are discussed
is rare. chain reaction [PCR] for antigen receptor on pp. 152, 602, and 603.
rearrangement [PARR]), immunohisto-
PHYSICAL EXAM FINDINGS chemistry): if uncertainty exists regarding Recommended Monitoring
• Epitheliotropic lymphoma typically involves the histologic diagnosis Regular CBC monitoring of remission status
chronic, progressive, generalized exfoliative (pp. 602 and 603)
dermatitis with crusting, ulceration, and TREATMENT
alopecia. PROGNOSIS & OUTCOME
• Epitheliotropic lymphoma may present as Treatment Overview
solitary or multiple ulcerated plaques or Treatment goal is complete remission with Biological behavior and responses to treatment
nodules involving oral mucosa. resolution of lesions. vary widely. Solitary epitheliotropic lymphoma

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