Tools for cancer diagnosis in cats and dogs.

Diagnostic Cytology

What is diagnostic cytology?
Cytology refers to the relatively fast and inexpensive examination of individual cells under the microscope. The cells are
commonly collected from sources such as skin masses, body cavity fluids, ear fluid, lymph nodes, urine or blood.

Cytology can sometimes provide definitive diagnosis of cancer and can aid the veterinarian in making a treatment
decision. The procedure is relatively simple and can avoid other more invasive, unnecessary and expensive diagnostic
techniques. The technique, however, also has its limitations and sometimes does not provide a clear yes/no answer. The
owner should keep in mind that the interpretation of the cytology test will largely depend on the person making the
conclusions and it may be a good idea to get a second opinion from an independent lab.

Typically, the cytology report will read:
Absence of atypical or abnormal cells OR
Atypical cells present but lack evidence of malignancy OR
Cells suggestive of malignancy OR
Cells strongly suggestive of malignancy OR
Cellular evidence conclusive for malignancy OR
Diagnosis deferred, such as unsuitable sample; resubmission suggested

How are cells collected?
Aspiration
This type of collection method is useful for collecting cells from masses, lymph nodes, discharges and internal organs.
The veterinarian will use a needle attached to a syringe and stick it inside of the mass to collect the samples for further
analysis. The procedure is relatively painless for the pet, typically no worse than an immunization.

Scraping
This type of collection method uses scalpel blades to scrape cell from firm surfaces.

Swabs
This type of collection method uses swabs to collect cells from mucosal surfaces such as the nose or rectum.

Interpretation of Results
The analysis of the cells can be done either by the attending veterinarian or sent to a laboratory. The sample will be
used to identify the various kinds of cells present and their appearance to determine whether inflammation or abnormal
cells are present. If cancerous cells are suspected to be present, the doctor/pathologist will attempt to identify which type
of cancer it is.