Summary
Between 1988 and 1991, feline immunodeficiency virus (fiv) infection status was evaluated in 1,160 cats examined at an oncology referral and general practice in Los Angeles, California. Twenty-nine (2.5%) cats were fiv positive. Neoplasia was present in 18 of the 29 (62%) cats. Sampling for neoplasia was intentionally biased in the oncology referral group. However, 33% (6/18) of fiv-infected cats with neoplasia originated from the general practice. Three neoplastic processes were observed; myeloproliferative disease (mpd; 5/18), lymphoma (lsa; 5/18), and squamous cell carcinoma (scc; 7/18). One cat had lsa and scc.
Extranodal sites of lsa were common (66%) in fiv-infected cats. Sites of lsa were submandibular and mesenteric lymph nodes, liver, kidneys, periorbital area, and diffuse (heart, pancreas, bladder). Sites of scc were sublingual (n = 2), nasal planum (n = 3), nasal planum and eyelids (n = 1), and mandible (n = 2). Feline leukemia virus co-infection was observed in 17% (5/29) of fiv-infected cats. The fiv-infected cats with mpd were young (range, 8 months to 13 years; median, 4 years) and had short survival duration (2, 6, 21, 134, 249 days) even in response to aggressive treatment. The fiv-infected cats with lsa were older (median age, 8 years; range, 4 to 14 years) and survived 60 days if untreated. Cats administered chemotherapy survived 39, 45, 217, and 243 days; the latter 2 cats had partial remission of 2 months' duration. Older fiv-infected cats had scc (median age, 12 years; remission range, 7 to 16 years) because of more frequent association of both diseases in older cats with outdoor environment.
Lymphocytic-plasmacytic lymphadenopathy was seen in 10 necropsied fiv-infected cats (4 without neoplasia, 3 with lsa, 1 with scc, and 2 with mpd). Lymphadenopathy associated with fiv may develop in one lymph node, and lymphoma may develop in another lymph node. Clinically, fiv-induced lymphadenopathy may be confused with progressive lymphoma.
