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CE
854 Vol. 25, No. 11 November 2003
Article #4 (1.5 contact hours)
Refereed Peer Review
KEY FACTS
■ Clinical signs of upper airway
obstruction should raise a
clinician’s suspicion for tracheal
neoplasia as a diagnostic
differential.
■ Caution during diagnostics and
therapeutics is needed to
prevent respiratory
embarrassment.
■ Treatment for tracheal tumors
may include surgical removal,
chemotherapy, and/or radiation
therapy, depending on tumor
type and stage.
V
Comments? Questions?
Email: compendium@medimedia.com
Web: VetLearn.com • Fax: 800-556-3288
Primary Tracheal Tumors
in Dogs and Cats
Texas A&M University
M. Raquel Brown, DVM, DACVIM (Internal Medicine)
Kenita S. Rogers, DVM, MS, DACVIM (Internal Medicine, Oncology)
ABSTRACT: Primary neoplasms of the trachea are uncommon in dogs and cats. Patients are
often middle aged or older, except dogs with osteochondromas. Clinical signs consistent with
tracheal obstruction, including dyspnea, wheezing, stridor, and cough, are common. Caution
should be used during diagnostics and therapeutics to prevent respiratory embarrassment.
Survey radiography often reveals the mass, and bronchoscopy allows direct visualization and
sampling of the lesion. Options for treatment include surgical excision, chemotherapy, radiation
therapy, or some combination of these methods. Most tumors respond well to complete surgical
excision, although lymphoma responds best to chemotherapy, with or without adjunctive
radiation therapy. Data on long-term follow-up are not available, but prognosis most likely
depends on tumor type and stage.
Primary neoplasms of the trachea are uncommon in animals and humans,
and both benign and malignant tumor types occur. 1–5 Most patients are
older, although young dogs with active osteochondral ossification sites are
at a higher risk of benign tracheal osteochondromas. 5,6 Clinical signs of upper
airway obstruction, including dyspnea, stridor, wheezing, exercise intolerance,
and cough, should raise the clinician’s suspicion of this problem, and radiography
often supports the diagnosis. 2 Treatment options include surgical removal,
chemotherapy, radiation therapy, and various combinations of these modalities.
Treatment recommendations depend on tumor type and staging. Prognosis for
these patients must be considered guarded because long-term follow-up of large
case series has not been reported. Prognosis most likely depends on tumor type. 2
SIGNALMENT
Canine primary tracheal tumors often present in a bimodal age distribution
1,2,6–16 (Table 1). Of the reported ages in the literature, eight dogs were 2
years of age and younger, and 10 were 6 years of age and older, with osteochondroma
and ecchondroma/osteochondromal dysplasia occurring in younger
dogs. 13–16 Both males and females are affected, with various breeds represented
(Table 1).
Cats are often older, with the mean age of reported cases being 9.5 years 1,7–27
(Table 2). Both sexes are represented, with domestic short-haired and Siamese
most commonly affected. Of the 19 reported cases of feline tracheal tumors,
feline leukemia virus (FeLV) status was reported in seven cats, and one had
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Compendium November 2003 Primary Tracheal Tumors in Dogs and Cats 855
Table 1. Reported Primary Tracheal Tumors in Dogs
Age
Study (years) Sex Breed Sign(s) Tumor Type Treatment Outcome
Carlisle et al1 12 FS Miniature Cough Adenocarcinoma None Euthanized
poodle Sneeze
Hill et al7 10 M Spitz Dyspnea Carcinoma — —
Harvey and 8 M Siberian Dyspnea Mast cell tumor Surgery —
Sykes11 husky
Carlisle et al1 13 F German Dyspnea Mast cell tumor None Euthanized
shepherd Stridor
Bryan et al10 “Aged” F Mix Dyspnea Leiomyoma Surgery Alive after
6 months
Black et al9 10 M Miniature Panting Leiomyoma Surgery Alive after
poodle 7 months
Chaffin et al2 10 FS Mix Dyspnea Extramedullary Surgery Alive after
plasmacytoma 3 months
Brodey et al12 7 F Mix Cough Osteosarcoma None Euthanized
Carlisle et al1 10 F Collie Dyspnea
Stridor
Chondroma Surgery —
Aron et al8 6 M German Dyspnea Chondrosarcoma Surgery Alive after
shepherd Cough
Voice change
12 months
Carlisle et al1 1 FS Doberman Dyspnea Chondrosarcoma Surgery Alive, but
Stridor metastasis
after 9
months
Hough et al15 0.5 F Labrador Dyspnea Osteochondroma Surgery Alive after
retriever 6 months
Withrow et al6 0.25 M Old Wheeze Osteochondroma Surgery Alive after
English
sheepdog
7 months
Dubielzig and 0.5 — Alaskan Dyspnea Osteochondroma None Died during
Dickey14 malamute diagnostics
Gourley et al16 0.9 F Alaskan Collapse Osteochondroma Surgery Alive after
malamute 8 months
Carlisle et al1 0.5 M German Wheeze Osteochondroma Surgery —
shepherd Cyanosis
Carb and 0.9 M Siberian Dyspnea Ecchondroma Surgery Alive after
Halliwell13 husky (osteochondral
dysplasia)
5 months
Carb and 2 F Mix Dyspnea Ecchondroma Surgery Alive after
Halliwell13 (osteochondral
dysplasia)
1 year
FS = female spayed; dashes indicate unknown data.
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856 Small Animal/Exotics Compendium November 2003
Table 2. Reported Primary Tracheal Tumors in Cats
Age FeLV/FIV
Study (years) Sex Breed Status Sign(s) Tumor Type Treatment Outcome
Brown and 10 FS DLH — Cough Lymphoma Medical Euthanized
Rogers25 Wheeze after 38 days
Brown and 11 CM DSH FeLV–, FIV– Dyspnea Lymphoma Medical Alive after
Rogers25 Radiation 21 months
Brown and 4 CM DSH FeLV–, FIV– Cough Lymphoma Medical Alive after
Rogers25 Wheeze 23 months
Brown and 13 CM DSH FeLV–, FIV– Wheeze Lymphoma Medical Alive after
Rogers25 Cyanosis Radiation 17 months
Schnieder 7 M Siamese FeLV+ Dyspnea Lymphoma Medical Alive after
et al23 Surgical 8 months
Zimmerman 9 M Siamese — Dyspnea Lymphoma Surgical Recurred
et al22 Euthanized
after 10 days
Beaumont17 11 CM DSH FeLV–, FIV– Dyspnea Lymphoma Surgical Systemic after
4 months
Kim et al24 13 FS Siamese FeLV–, FIV– Dyspnea Lymphoma None Euthanized
Beaumont17 11 FS Siamese — Dyspnea Adenocarcinoma None Euthanized
Cain and
Manley
10 — Siamese — Cough Adenocarcinoma Surgical —
19
Evers et al20 12 CM DSH FeLV– Dyspnea Adenocarcinoma Surgical Recurred
Euthanized
after 12
months
Zimmerman 12 M Persian — Dyspnea Adenocarcinoma Surgical Alive after
et al22 Cough 12 months
Evers et al20 12 FS DSH — Dyspnea Adenocarcinoma Surgical Alive after
3 months
Neer and 7 — DLH — Wheeze Adenocarcinoma Surgical Recurred
Zeman18 Dyspnea Euthanized
after 17
months
Carlisle et al1 6 FS Domestic — Stridor Seromucinous
carcinoma
None Euthanized
Glock21 6 — — — Weight
loss
Adenoma None Euthanized
Lobetti and 11 CM DSH — Dyspnea Squamous cell None Euthanized
Williams26 carcinoma
Carlisle et al1 9 M Domestic — Wheeze Carcinoma Surgical Died after
Dyspnea 15 months
Veith27 2 CM DSH — Dyspnea Squamous cell
carcinoma
None Died
CM = castrated male; DLH = domestic long-haired; DSH = domestic short-haired; FS = female spayed; dashes indicate unknown data.
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Compendium November 2003 Primary Tracheal Tumors in Dogs and Cats 857
Figure 1—Thoracic radiograph of a cat with intratracheal lymphoma. Note the
multiple masses within the tracheal lumen (arrows). (From Brown MR, Rogers
KS, Mansell KJ, et al: Primary intratracheal lymphosarcoma in four cats.
JAAHA 39:468–472, 2003; with permission)
positive results on an immunofluorescent antibody test.
Of the five cats tested for feline immunodeficiency
virus (FIV), all had negative results.
HISTORY AND CLINICAL SIGNS
Acute, intermittent, or chronic and progressive signs
of tracheal obstruction may prompt presentation
of the patient to the veterinarian. 28 Dyspnea, wheezing,
exercise intolerance, and coughing are common complaints.
2,29 Depression, voice change, intermittent
cyanosis, inability to bark, collapse, or weight loss may
also be noted. 8,16,21 Although some patients present with
no overt clinical signs, many are in obvious respiratory
distress. Along with the clinical signs already listed,
referred upper airway sounds may be auscultated. 29
Patients may become cyanotic with the stress of physical
examination. Cats may begin open-mouth breathing
or may present in a crouched stance with their head
and neck extended. 4 Patients may show a preference for
sternal recumbency over lateral recumbency. 4 A 6month-old
Alaskan malamute that presented for osteochondroma
of the trachea had obvious hemorrhage at
the laryngeal opening. 14
DIAGNOSTICS
When the patient’s condition permits, radiography is
the diagnostic procedure of choice. 30 Tracheal tumors are
often discernible on survey radiography because these
masses are outlined by tracheal air, which provides a natural
contrast medium 29 (Figure 1). If tracheal neoplasia is
considered a diagnostic differential and the thoracic radiographs
are within normal limits, radiographs of the
neck should be obtained. Intratracheal masses may present
in a variety of locations within the trachea, from just
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caudal to the larynx to the carina. Overexpansion
of the lungs, flattening of the diaphragm,
and prominent pulmonary vasculature
secondary to increased air content of
the lungs have been noted in cats with
intratracheal tumors. 25 If severe respiratory
embarrassment is present, oxygen therapy
or sedation may be necessary to obtain
diagnostic radiographs without endangering
the patient. 4
Bronchoscopy offers direct visualization
of the mass(es) (Figure 2), unless substantial
hemorrhaging is present. Brush
cytology and biopsies may also be
obtained for evaluation 30 (Figure 3). Brush
cytology offers the clinician the potential
to make an immediate diagnosis and provide
immediate treatment.
DIFFERENTIAL DIAGNOSIS
Intratracheal mast cell tumor, 1,11 adenocarcinoma, 1
carcinoma, 7 leiomyoma, 9,10 chondroma, 10 osteosarcoma,
12 extramedullary plasmacytoma, 2 rhabdomyosarcoma,
and chondrosarcoma 1,8 have been reported in
dogs. Five cases of osteochondroma 1,6,14–16 and two cases
of ecchondroma/osteochondromal dysplasia 13 have
been reported in young dogs. These benign tracheal
osteocartilaginous tumors grow in synchrony with the
rest of the musculoskeletal system and, therefore,
should stop growing with skeletal maturity. Intraluminal
adenocarcinoma, 17–22 lymphoma, 17,22–25 squamous
cell carcinoma, 26,27 and adenoma 21 have been reported
in cats. Intratracheal neoplasms must be differentiated
from nonneoplastic intraluminal masses. Differentials
for nonneoplastic intraluminal masses include polyps, 31
eosinophilic granulomas, 32 nodular amyloidosis, 33 tissue
reaction to Filaroides osleri, 34 chondromatous hamartoma,
35 papillomatosis, 36 and hyperplastic tracheitis of
unknown cause. 37 Stenosis of the tracheal lumen may
be iatrogenically induced via excessive inflation of an
endotracheal tube or other trauma. 38,39
STAGING
Ideally, all dogs and cats with neoplasia should
undergo staging before definitive treatment recommendations
are made. 30 Intratracheal neoplasms causing respiratory
compromise sometimes present an exception
to this rule because immediate therapy may need to be
initiated. If time permits, clinical pathology and imaging
modalities should be performed. For all animals, a
complete blood cell count, chemistry profile, and urinalysis
should be conducted. 30 FeLV and FIV status
should be determined in all cats. Thoracic radiographs

858 Small Animal/Exotics Compendium November 2003
Figure 2—Photograph taken during bronchoscopy of a dog
with an intratracheal tumor.
should be evaluated for evidence of metastasis. Abdominal
ultrasonography allows evaluation of systemic disease,
including systemic neoplasia, when abdominal
palpation may not fully define abdominal disease. Cats
with heart murmurs should undergo echocardiography
before anesthesia, if possible. This not only allows a
proper anesthetic induction, protocol to be chosen but
also potentially identifies any underlying or complicating
disease processes. The acquired information can
also guide treatment choices (e.g., Is the animal a good
candidate for chemotherapy?).
TREATMENT
Treatment options include surgical removal,
chemotherapy, radiation therapy, or a combination of
these modalities, depending on tumor type and stage. 2
Surgical removal is the only reported treatment attempted
in dogs, either by resection of the trachea 1,2,8,10,11,15,16 or
endoscopic removal by snaring. 6 Surgery is the treatment
of choice for solitary tracheal tumors without evidence of
metastatic disease. 30 Surgical therapy may provide shortterm
palliative relief of airway obstruction for tracheal
tumors exhibiting local and metastatic spread. Although
outcome was not reported for one dog with a mast cell
tumor, 11 follow-up times were reported for most dogs
with osteochondroma (6, 7, and 8 months), 6,15,16 leiomyoma
(6 and 7 months), 9,10 ecchondroma/osteochondromal
dysplasia (5 and 12 months), 13 extramedullary plasmacytoma
(3 months), 2 and chondrosarcoma (9 and 12
months). 8 Therefore, short-term survival with surgical
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Figure 3—Histopathology from a cat with an intratracheal
mass diagnosed as lymphoma. (From Brown MR, Rogers KS,
Mansell KJ, et al: Primary intratracheal lymphosarcoma in
four cats. JAAHA 39:468–472, 2003; with permission)
resection appears adequate, but long-term prognosis cannot
be fully evaluated.
Cats with intratracheal adenocarcinoma have been
followed for up to 17 months. Two cats that had surgical
resection were clinically well at 3 and 12 months. 20,22
One cat had an adenocarcinoma suctioned during
bronchoscopy twice, affording the cat an additional 17
months of life. 18 Intratracheal lymphoma has not
responded well to surgical removal alone. One cat had
recurrence of disease within 10 days, 22 and another had
systemic lymphoma at 4 months postoperatively. 17
The main indication for radiation and chemotherapy
is for intratracheal tumors of lymphoid origin. This
extranodal lymphoma is quite sensitive to radiation
therapy and should be considered immediately after the
cytologic or histologic diagnosis has been made. Radiation
provides a rapid reduction of tumor burden, allowing
a more immediate improvement in the patient’s respiratory
status. Chemotherapy can also delay local or
systemic recurrence of lymphoma. Two cats were tumor
free for 17 and 21 months after a combination of
chemotherapy and radiation was used to treat intratracheal
lymphoma. 25
PROGNOSIS
Prognosis depends on tumor type, stage of disease,
and underlying disease. Osteochondromas of young
dogs appear to carry the best prognosis. Other canine
and feline tracheal tumors have not been followed longterm
after surgical resection, but patients appear to
respond well to surgery, reportedly with survival times
of several months. Cats with tracheal lymphoma may
do well after radiation, systemic chemotherapy, or a
combination of these two modalities.

Compendium November 2003 Primary Tracheal Tumors in Dogs and Cats 859
CONCLUSION
Primary intratracheal neoplasia is uncommon in dogs
and cats, with only 37 cases reported in the veterinary
literature. Clinical signs are associated with airway
obstruction, including dyspnea, wheezing, and exercise
intolerance. Radiography often reveals a soft tissue density
within the tracheal lumen. Bronchoscopy allows
direct visualization and sampling for cytology and
histopathology. Treatment recommendations may
include surgical removal, chemotherapy, radiation therapy,
or a combination of these methods, depending on
the tumor type and stage. Until long-term follow-up is
observed and reported, the prognosis for these patients
must be considered guarded. Prognosis most likely
depends on tumor type.
REFERENCES
1. Carlisle CH, Biery DN, Thrall DE: Tracheal and laryngeal
tumors in the dog and cat: Literature review and 13 additional
patients. Vet Radiol 32(5):229–235, 1991.
2. Chaffin K, Cross AR, Allen SW, et al: Extramedullary plasmacytoma
in the trachea of a dog. JAVMA 212(10):1579–1581,
1998.
3. Ogilvie GK, Moore AS: Tumors of the respiratory tract, in
Feline Oncology. Yardley, PA, Veterinary Learning Systems, 2001,
pp 368–384.
4. Stann SE, Bauer TG: Respiratory tract tumors. Vet Clin North
Am Small Anim Pract 15:535–556, 1985.
5. Withrow SJ: Tumors of the respiratory system, in Clinical Veterinary
Oncology. Philadelphia, Lippincott, 1989, pp 215–233.
6. Withrow SJ, Holmberg DL, Rosychuk RA, et al: Treatment of a
tracheal osteochondroma with an overlapping end-to-end tracheal
anastomosis. JAAHA 14(4):469–473, 1978.
7. Hill JE, Mahaffey EA, Farrell RL: Tracheal carcinoma in a dog.
J Comp Pathol 97:705–707, 1987.
8. Aron DN, DeVries R, Short CE: Primary tracheal chondrosarcoma
in a dog: A case report with description of surgical and
anesthetic techniques. JAAHA 16:31–37, 1980.
9. Black AP, Liu S, Randolph JF: Primary tracheal leiomyoma in a
dog. JAVMA 179:179, 905–907, 1981.
10. Bryan RD, Frame RW, Kier AB: Tracheal leiomyoma in a dog.
JAVMA 178:1069–1070, 1981.
11. Harvey HJ, Sykes G: Tracheal mast cell tumor in a dog. JAVMA
180:1097–1100, 1982.
12. Brodey RS, O’Brien J, Berg P, et al: Osteosarcoma of the upper
airway in the dog. JAVMA 155:1460–1464, 1969.
13. Carb A, Halliwell WH: Osteochondral dysplasias of the canine
trachea. JAAHA 17:193–199, 1981.
14. Dubielzig RR, Dickey DL: Tracheal osetochondroma in a young
dog. Vet Med Small Anim Clin 73:1288–1290, 1978.
15. Hough JD, Krahwinkel DJ, Evans AT, et al: Tracheal osteochondroma
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16. Gourley IG, Morgan JP, Gould DH: Tracheal osteochondroma
in a dog: A case report. J Small Anim Pract 11:327–335, 1970.
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17. Beaumont PR: Intratracheal neoplasia in two cats. J Small Anim
Pract 23:29–35, 1982.
18. Neer TM, Zeman D: Tracheal adenocarcinoma in a cat and
review of the literature. JAAHA 23(4):377–380, 1987.
19. Cain GR, Manley P: Tracheal adenocarcinoma in a cat. JAVMA
182(6):614–616, 1983.
20. Evers P, Sukhiani HR, Sumner-Smith G, et al: Tracheal adenocarcinoma
in two domestic shorthaired cats. J Small Anim Pract
35:217–220, 1994.
21. Glock R: Primary pulmonary adenomas of the feline. Iowa State
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unterschiedlichen trachealtmoren bei katzen. Kleintierpraxis
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23. Schnieder PR, Smith CW, Feller DL: Histiocytic lymphosarcoma
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of the trachea in a cat. J Vet Med Sci 58(7):703–
706, 1996.
25. Brown MR, Rogers KS: Primary intratracheal lymphoma in four
cats. JAAHA, in press.
26. Lobetti RG, Williams MC: Anaplastic tracheal squamous cell
carcinoma in a cat. J South Afr Vet Assoc 63:132–133, 1992.
27. Veith LA: Squamous cell carcinoma of the trachea in a cat.
Feline Pract 4(1):30–32, 1974.
28. Norris AM, Henderson RA, Withrow SJ: Respiratory system, in
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1985, pp 2583–2592.
29. Ettinger SJ, Ticer JW: Diseases of the trachea, in Textbook of Veterinary
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1989, pp 795–815.
30. Bell FW: Neoplastic diseases of the thorax. Vet Clin North Am
Small Anim Pract 17:387–409, 1987.
31. Sheaffer KA, Dillon AR: Obstructive tracheal mass due to an
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32. Brovida C, Castagnaro M: Tracheal obstruction due to an
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33. Dill GS, Stookey JL, Whitney GD: Nodular amyloidosis in the
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34. Burrows CF, O’Briend JA, Biery DN: Pneumothorax due to
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Pathol 88:590–591, 1964.
37. DeRick A, VanBree H, Hoorens J, et al: Tracheal obstruction
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860 Small Animal/Exotics Compendium November 2003
ARTICLE
CE
#4 CE TEST
The article you have read qualifies for 1.5 contact
hours of Continuing Education Credit from
the Auburn University College of Veterinary Med-
icine. Choose the best answer to each of the follow-
ing questions; then mark your answers on the
postage-paid envelope inserted in Compendium.
1. Because canine tracheal neoplasms present in a bimodal
age distribution, dogs 2 years of age or younger are
most likely to present with
a. mast cell tumor. c. chondrosarcoma.
b. leiomyoma. d. osteochondroma.
2. Which of the following are reported clinical signs for
patients with tracheal tumors?
a. wheezing and dyspnea
b. cough and exercise intolerance
c. voice change or inability to bark
d. all of the above
3. Which of the following is the diagnostic procedure of
choice for confirming suspicions of an intratracheal
mass?
a. contrast radiography c. bronchoscopy
b. survey radiography d. exploratory surgery
4. Which of the following parasites may cause intratracheal
nodules as a result of tissue reaction against the
parasite?
a. Oslerus hirthi
b. Aelurostrongylus abstrusus
c. Filaroides osleri
d. Paragonimus kellicotti
5. An unstable, dyspneic cat has been anesthetized, and
bronchoscopy has revealed a mass. Cytology of the
mass reveals lymphoma. Before the cat recovers from
anesthesia, the therapy that would offer the quickest
reduction of the tumor burden would be
a. chemotherapy.
b. radiation therapy.
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c. surgical excision.
d. medical management with prednisone.
6. Surgical resection is the treatment of choice for all of
the following except
a. lymphoma.
b. adenocarcinoma.
c. osteochondroma.
d. leiomyoma.
7. Which of the following is considered a benign osteocartilaginous
tumor that grows in synchrony with the
rest of the musculoskeletal system and should stop
growing at skeletal maturity?
a. leiomyoma
b. chondroma
c. osteochondroma
d. osteosarcoma
8. When a patient presents with clinical signs consistent
with a tracheal tumor, the first priority should be to
a. obtain plain radiographs to identify the problem.
b. stabilize the patient with oxygen and other supportive
measures.
c. perform bronchoscopy to obtain a sample for cytology
and histopathology.
d. submit blood for a complete blood cell count and
chemistry profile.
9. All of the following have been noted in cats with intratracheal
tumors except
a. overexpansion of the lungs.
b. flattening of the diaphragm.
c. underexpansion of the lungs.
d. prominent pulmonary vasculature.
10. Which of the following statements regarding FIV and
FeLV is true?
a. FIV is common in cats with tracheal neoplasia.
b. FIV and FeLV are common in cats with tracheal
neoplasia.
c. FIV testing was reported in four of 19 cats, and all
cats were negative for the virus.
d. All cats with tracheal neoplasia are FeLV positive.