Page 468 - Problem-Based Feline Medicine

460 PART 7 SICK CAT WITH SPECIFIC SIGNS

Cats with high-grade lymphoma should be treated intestinal epitheliotropic lymphoma have a better prog-
with a multi-agent protocol. nosis than with other forms of abdominal lymphoma.
In one report, 69% achieved complete remission with
Cats with low-grade lymphoma (usually alimentary)
a median survival of 22.8 months.
may be treated with less aggressive protocols such as
prednisone and chlorambucil. Most cats tolerate chemotherapy for lymphoma and
fatal complications of chemotherapy are rare.
Splenectomy may be considered for splenic lymphoma
if there is no evidence of lymphoma at another site.
Because there is always the possibility of undetected Solid tumors***
microscopic lymphoma at another site, surgery should
be reserved for cats where there is poor response to, Classical signs
or unacceptable side effects with, chemotherapy.
● Chronic anorexia, lethargy, weight loss.
Surgical removal of a gastrointestinal lymphomatous
mass should be reserved for cats where the tumor is Clinical signs
causing gastrointestinal obstruction or perforation.
Anorexia, lethargy and weight loss.
Surgical removal in addition to chemotherapy in
other cases does not appear to be of added benefit. Variable fever, vomiting, diarrhea, icterus, palpable
mass, depending upon the location of the tumor.
Prognosis ● Absence of vomiting or diarrhea does not rule out a
gastrointestinal tumor.
Response to chemotherapy in several case series pro-
Abdominal fluid ± abdominal distention may be
vides general information, but it is difficult to give a
present because of pre-hepatic or hepatic portal
prognosis for an individual cat. Ultimately the only way
hypertension, lymphatic obstruction or hemor-
to determine prognosis is to treat the cat and observe
rhage. A large abdominal mass may contribute to
response.
abdominal distention.
The prognosis for multicentric lymphoma is discussed ● Splenic or hepatic hemangiosarcoma is the most
in The Cat With Enlarged Lymph Nodes. common neoplastic cause of hemoperitoneum, but
it is much less common than in the dog. Other
In recent reports, about one-third to two-thirds of cats
tumors may also spontaneously bleed.
with alimentary lymphoma achieved a complete
● Abdominal fluid has been recognized with many
remission with chemotherapy, many of the other cats
solid tumors, including those of the liver, pan-
achieved a partial remission (with overall response
creas, kidney, intestinal tract and peritoneum
rates up to 90%), and 1-year survival about 20–40%.
(mesothelioma).
Some of these cats will become long-term survivors
and are considered to be cured. Iron-deficiency anemia from chronic gastrointestinal
hemorrhage may occur with gastrointestinal adenocar-
Regardless of anatomic location, usually only cats that
cinomas.
achieve a complete remission with induction chemother-
apy have the possibility of being cured.
Diagnosis
FeLV status, FIV status, sex, tumor burden and loca-
tion, histologic grade and immunophenotype do not Abdominal radiography or ultrasonography may
independently consistently predict achievement of demonstrate an abdominal mass, organomegaly or peri-
remission, duration of remission or survival. Some of toneal fluid.
the weakness of prognostic factors may reflect differ-
Biopsy of suspected neoplastic tissue.
ent criteria for anatomic location and histologic grade
as well as the poor statistical power of relatively small Abdominal fluid may be a transudate, modified
case series. Certain combination of factors may affect transudate, chylous or hemorrhagic effusion, and
prognosis. For example, cats with well-differentiated may contain neoplastic cells.