Perl S., 1Lahav D., 2Meltzer R., 2Kopla A. and 3Waner. T.
Vol. 60 3) 2005
1. Kimron Veterinary Institute, P.O. Box 12, Beit Dagan 50250.
2. Veterinary Clinic, 12 Hasukah Street, Rishon LeZion 75100
3. Veterinary Clinic, 9 Meginay Hagalil Street, Rehovot 76200.
Corresponding author: Dr. Trevor Waner. B.V.Sc., Ph.D., Dipl ECLAM
Veterinary Clinic, 9 Meginay Hagalil Street, Rehovot 76200
Phone 972-8-9492225
e-mail: [email protected]
In this report we describe the clinical and pathologic findings of a nasal cavity
fibrosarcoma extending through the cribriform plate into the brain of a 9-year old
Persian male intact cat. The report documents a rare occurrence. Nasal cavity
neoplasms have been infrequently reported in cats. To the best of our knowledge this
is the first case in the cat of a nasal cavity fibrosarcoma invading the brain.
Tumors involving the nasal cavity are rare in dogs and cats (1-3). The
prevalence of tumors of the nasal and paranasal sinuses in the cat has been
reported to vary between 1 to 4% of all tumors diagnosed in cats (1, 4).
Squamous cell carcinomas are the most frequent tumor of the nasal passages
and paranasal sinuses of cats (5). About 91% of tumors in this region have
been found to be malignant in the cat (5). The extension of a fibrosarcoma
from the nasal cavity into the brain is a rare event, and to the best of our
knowledge this has not been reported previously. In this report we describe
the clinical and pathologic findings in a cat with a unilateral fibrosarcoma
extending through the cribriform plate into the brain.
Case report
A 9-year-old male white Persian breed cat was referred to a veterinary
clinic with signs of ocular discharge. Six months later it presented with signs
of depression and generalized weakness. After a few weeks it appeared to
the owners that the cat was confused and unable to recognize them. Shortly
thereafter the cat became weaker and began showing signs of lack of
coordination. At the request of the owners, due to the central nervous
involvement, the cat was euthanized.
Necropsy findings
At necropsy, a soft whitish-gray mass of 2 x 5 cm was present in the left
nasal cavity. The tumor mass had destroyed the turbinate bones and eroded
through the lamina cribosa of the ethmoid bone and penetrated the brain in
the region of the frontal and the left olfactory lobes. No lesions were detected
in the regional lymph nodes. No other pathological findings were present in
any other internal organ.
Histopathological findings
The normal architecture of the nasal cavity was completely replaced by
compact neoplastic tissue. The tumor mass was poorly delineated, highly
cellular and composed of interlacing streams and whorls of spindle shaped
cells. The neoplastic cells had indistinct boarders with a moderate amount of
eosinophilic fibrillar cytoplasm. The nuclei were round to oval with lightly
stippled chromatin, prominent nuclear borders, and a single, usually centrally
located nucleolus. Mitoses averaged about 1-2 per high power field.
Multifocally within the mass there were areas of necrosis, hemorrhage and
infiltrates of lymphocytes. Within the nasal cavity the neoplastic cells had
replaced bone matrix of the turbinates (Fig. 1). In the brain, the tumor
extended into the neuropil of the frontal lobe in a number of foci (Fig. 2).
Adjacent to the invasive tumor there were hemorrhages with vacuolation and
necrosis of the neuropil. A number of multinucleated giant cells was evident,
along with Gitter cells, some containing hemosiderin.
Figure 1.
Nasal cavity. A highly cellular mass composed of interlacing
streams and whorls of spindle shaped cells, invading and
replacing bone matrix of the turbinates, and infiltrating into the
submucosa underlying the respiratory epithelium.
Figure 2.
Fibrosarcoma originating in the nasal cavity of a
into the neuropil of the frontal lobe. Necrosis of t
presence of multinucleated giant cells are eviden
A specific diagnosis was not made based on clinical signs. Classical clinical
signs include sneezing, nasal or ocular discharge, which may be bloody and
dyspnea (4). With the exception of an ocular discharge, there was no
indication of nasal cavity neoplasia. Neurological signs of neoplasia were
apparent at a late stage of the disease, but were not specific for nasal cavity
neoplasia with extension to the brain.
The signalment for a cat with nasal or paranasal cavity neoplasia includes
male castrated cats older than 6 years of age (4). In this regard it is interesting
to note that the cat is the only species in which a sex difference in the
occurrence of nasal neoplasms has been found, with males nearly twice as
likely to have nasal neoplasms than females (5). Furthermore data indicates
that castrated male cats are at greatest risk (4). The cat presented in this case
was a 9-year old intact male. There is inadequate information in the literature
regarding the incidence of the tumors in different breeds of cats, although a
number of cases have been reported in the Persian breed (4).
In a review of 35 cases of naturally occurring microscopically confirmed
tumors of the nasal cavity and paranasal sinuses of cats, only one was
reported as a fibrosarcoma (5). In another survey, 16 cases with
nasal/paranasal tumors were presented and only one case was diagnosed as
a fibrosarcoma which did not invade the brain of a 9-year-old male castrated
cat (4). Overall, of the 16 cases reported two were carcinomas, both of which
invaded the brain.
From the literature it appears that besides the scarcity of this tumor in the
nasal cavity of cats, its invasion into the brain is even more uncommon
although the majority of nasal tumors are located near the cribriform plate (1).
At necropsy, the tumor was found to be located unilaterally. Although no data
are available for cats, approximately half of tumors in the dog invade the
contralateral nasal cavity at the time of diagnosis (6).
In summary, this report documents a rare occurrence of a fibrosarcoma of the
nasal cavity of a cat with extension into the brain. Nasal cavity neoplasms
have been infrequently reported in cats with only two instances of
fibrosarcomas documented in the literature. To the best of our knowledge this
is the first case in the cat of a nasal cavity fibrosarcoma invading the brain.
1. Ogilvie, G.R. and LaRue, S.M. Canine and feline nasal and paranasal
tumors. Vet. Clinics of North America. Small Animal Pract. 22:1133-1143,
2. Nyska, A., Klopfer, U., Perl S., Nobel, T.A. and Bark, H. Tumors in the
nasal cavity of dogs — five case reports. Isr. J. Vet. Med. 37:145-150, 1980.
3. Legendre, A.M., Carrig, C.B., Howard, D.R. and Dade, A.W. Nasal tumor in
a cat. JAVMA. 167:481-483, 1975.
4. Cox, N.R., Brawner, W.R., Powers, R.D. and Wright, J.C. Tumors of the
nose and paranasal sinuses in cats: 32 cases with comparison to a national
database (1977 through 1987). JAAHA. 27:339-347, 1991.
5. Madewell, B.R., Priester, W.A., Gillette, E.L. and Synder, S.P. Neoplasms
of the nasal passages and paranasal sinuses in domesticated animals as
reported by 13 veterinary colleges. Am. J. Vet. Res. 37: 851-856, 1976.
6. Patnaik, A.K.(1989) Canine sinonasal neoplasms: Clinicopathological study
of 285 cases. JAAHA. 25: 103-114, 1989.

feline nasal cavity fibrosarcoma with extension into the brain