Small Animal Dermatology, 3rd edition

CHAPTER 41 PRE- AND PARANEOPLASTIC SYNDROMES 623

 Feline paraneoplastic dermatoses:
Pancreatic/hepatic paraneoplastic alopecia: severe atrophy of hair follicles and

adnexa; miniaturization of hair bulbs; mild acanthosis; variable absence of stra-

tum corneum; variable mixed superficial perivascular infiltrates of neutrophils,

eosinophils, and mononuclear cells; some have secondaryMalassezia infec-

tions/primary tumor – usually pancreatic adenocarcinoma, rarely primary bile

duct or hepatocellular carcinomas/metastatic nodules – common in the liver,

lungs, pleura, and peritoneum

Exfoliative dermatitis associated with thymoma: cell-poor hydropic interface

dermatitis with apoptosis of basal keratinocytes, pockets of satellitosis, and lym-

phocytic dermal infiltrate.

THERAPEUTICS

 Canine preneoplastic dermatoses:
Actinic keratoses:

Avoid exposure to UVL by keeping patients indoors and by applying sun-

block

Vitamin E 200 mg PO BID less than 10 kg body weight; 400 mg PO BID

greater than 10 kg body weight; vitamin C 500 mg PO BID; beta-carotene

30 mg PO BID to q24h; vitamin A 400–600 IU/kg PO q24h – may have a

protective effect

Topical corticosteroids: reduce localized areas of inflammation

Prednisolone 0.5 mg/kg PO q24h then tapered dosage: reduce significant

inflammation

Cephalexin 22 mg/kg PO BID: secondary bacterial furunculosis; alternative

antibiotics selected by culture and sensitivity test results

Tretinoin 0.1% (Retin-A): apply daily to individual lesions for 14 days; then

2–3 times weekly; may cause irritation

Isotretinoin 1 mg/kg PO q24h for 30 days; then alternate days or as needed

to control lesions

Firocoxib 5 mg/kg PO q24h: overexpression of cyclooxygenase (COX-2)

documented in actinic keratoses in humans and dogs; improvement noted

with use of COX-2 selective inhibitor

Cutaneous lymphocytosis: undetermined; too few cases documented; poor

response to corticosteroids

Cutaneous mastocytosis:

Spontaneous resolution

Antihistamines: hydroxyzine 1 mg/kg PO BID; chlorpheniramine 0.2–

0.5 mg/kg PO BID

Corticosteroids: prednisolone 0.5 mg/kg PO q24h then tapered dosage

Nodular fasciitis: surgical excision curative.

 Canine paraneoplastic dermatoses:
Cutaneous (primary nodular) amyloidosis: