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Lymphoma, Multicentric (Cat) 607

Lymphoma, Multicentric (Cat) Client Education
Sheet
VetBooks.ir Diseases and Disorders

BASIC INFORMATION
noncompressible crainial thorax and
suggest pleural effusion. infiltration in marrow or secondary to
immune-mediated destruction) or presence
Definition ○ Renal: presenting sign is acute azotemia, of circulating lymphoblasts (i.e., leukemia)
Systemic malignant neoplasm of lymphoid which may largely or entirely resolve with • Serum biochemistry panel: to identify liver
origin chemotherapy; physical exam reveals or renal abnormalities that may develop
marked bilateral renomegaly; central secondary to organ involvement and may
Synonyms nervous system relapse is reported. alter ability to metabolize or eliminate
Lymphosarcoma, malignant lymphoma, non- ○ Spinal: often FeLV infected; presenting chemotherapeutic drugs
Hodgkin lymphoma (human) sign is hindlimb paraparesis; many have • Urinalysis ± urine culture and sensitivity:
concurrent malignant lymphoblasts in to further evaluate renal function and
Epidemiology bone marrow (p. 932). identify urinary tract infection secondary
SPECIES, AGE, SEX ○ Nasal: unique form of lymphoma, often to immunocompromise
• Most common hematopoietic malignancy localized and may be treated with radiation • FeLV serologic testing: FeLV antigenemia is
• Disease forms/anatomic presentations have therapy associated with certain forms of lymphoma
changed over the past decades, coincident ○ Cutaneous and may be prognostic (see Prognosis &
with decreases in feline leukemia virus Outcome below).
(FeLV) infection rates and FeLV-associated HISTORY, CHIEF COMPLAINT • Serum cobalamin level in cats with suspected
lymphoma. • Highly varied presentation (see Disease low-grade alimentary lymphoma
• Can develop at any age Forms/Subtypes above) • Aspiration and cytologic evaluation of affected
• Siamese cats may be at increased risk for • Generalized peripheral lymphadenopathy organ(s) or site(s): to provide diagnosis
certain forms of lymphoma. is common in dogs but rare in cats with
lymphoma. Advanced or Confirmatory Testing
RISK FACTORS • If lymphoma is identified cytologically, the
• FeLV and possibly feline immunodeficiency PHYSICAL EXAM FINDINGS following tests are indicated for staging before
virus (FIV) infection status influences age Physical exam findings vary and reflect the initiation of chemotherapy:
and anatomic location at which lymphoma organs involved (see Disease Forms/Subtypes ○ ± Biopsy of affected organ(s): for definitive
develops. above). diagnosis and histologic grading
• Household exposure to environmental ○ Thoracic radiographs: to identify lymph-
tobacco smoke (i.e., secondhand smoke). Etiology and Pathophysiology adenopathy, cranial mediastinal mass,
In one study, cats exposed to tobacco • Rapid onset and disease progression over pleural effusion, pulmonary involvement
smoke had a 2.4-fold increased risk of days to weeks (most types) ○ Abdominal ultrasound exam: to identify
lymphoma, which increased with duration • Low-grade lymphoma (often GI) typically hepatic, splenic, renal, or GI involve-
of exposure and number of smokers in the presents with chronic history. ment, lymphadenopathy, or other sites
house. of lymphoma
Clinical Presentation DIAGNOSIS ○ Bone marrow aspiration for cytologic exam
(p. 1068): to identify marrow involvement
DISEASE FORMS/SUBTYPES Diagnostic Overview and/or develop better understanding of
• Histologic grade Diagnosis is suspected based on detection of the cause of cytopenias
○ High-grade or lymphoblastic lymphoma: a mass lesion/infiltration in affected organ or ○ Phenotyping (flow cytometry, polymerase
most common; rapid onset and progres- site with associated clinical signs. Aspiration chain reaction [PCR] for antigen receptor
sion; affected cells are large lymphoblasts. cytology of the mass or site is often diagnostic. rearrangement [PARR], immunocyto-
○ Low-grade or lymphocytic/small cell chemistry, immunohistochemistry): to
lymphoma: most often reported with Differential Diagnosis determine B-cell versus T-cell origin
gastrointestinal (GI) lymphoma; chronic • Other neoplasms (e.g., leukemia, mast cell • If financial restrictions prohibit these tests,
insidious onset; affected cells are well tumor) one may elect to omit certain tests (e.g.,
differentiated and similar in appearance • Multicentric: other neoplasms (e.g., mast cell if CBC results are unremarkable, okay to
to small lymphocytes. tumor), cholangitis-cholangiohepatitis and omit a bone marrow aspiration), provided
• Anatomic distribution other hepatopathies, pancreatitis client understands that sites of disease may be
○ Multicentric: typically lymph node, spleen, • Mediastinal: other neoplasms (e.g., thymoma, missed and staging and follow-up monitoring
and/or liver involvement; presenting signs mesothelioma), heart disease, pyothorax, will be less certain.
and physical exam findings vary with chylothorax, feline infectious peritonitis,
organ(s) affected. diaphragmatic hernia TREATMENT
○ Alimentary (GI) (p. 604): older cats; • Renal: acute kidney injury, polycystic kidney
majority are FeLV negative; presenting disease, pyelonephritis Treatment Overview
signs include anorexia, weight loss, • Nasal: other neoplasms (e.g., adenocarcinoma), Treatment involves administration of che-
vomiting, and diarrhea; physical exam rhinitis, inflammatory polyps, cryptococcosis motherapy to achieve complete remission
may reveal palpable abdominal mass. • Alimentary: inflammatory bowel disease, while maintaining good quality of life for the
○ Mediastinal: young cats; most are FeLV granulomatous bowel disease, parasitism, other patient. Special drug-handling requirements and
infected; thymus, mediastinal, and sternal neoplastic and non-neoplastic GI disorders potentially severe or life-threatening adverse
lymph nodes may be involved (rarely, patient effects exist with many chemothera-
superficial cervical nodes are affected); Initial Database peutics; these concerns and rapid evolution of
presenting signs include dyspnea, • CBC: to identify anemia, thrombocytopenia, protocols warrant consultation with/referral to
tachypnea; physical exam may reveal a and/or neutropenia (due to lymphoblast an oncologist.

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