Chemistry

What is a chemistry panel?

A chemistry panel is used to evaluate internal organ function (liver, kidneys, gastrointestinal tract) and electrolytes that when abnormal, may be indicative of various disease processes.  Abnormalities in liver function parameters (glucose, albumin, bilirubin, BUN – blood urea nitrogen, and cholesterol) and liver enzymes (ALT, ALP, AST) may suggest underlying liver dysfunction or damage, or may be due to administration of certain drugs such as steroids (which commonly leads to mild to moderate liver enzyme elevation). Elevated kidney values (BUN and creatinine) and abnormalities in certain electrolytes (calcium, phosphorous, potassium, magnesium) may indicate underlying renal insufficiency or dehydration.  While some of these parameters when abnormal are suggestive of certain conditions or side effects of specific medications, they generally are not specific and may be due to a variety of issues (or may also be insignificant in some cases).  As a result, abnormalities on a chemistry panel may prompt your veterinarian to recommend further diagnostic testing and/or empirical treatment. 

How is a chemistry panel useful for cancer patients?

Certain cancers that may present with diffuse organ involvement (such as lymphoma, certain leukemias, histiocytic disease, and mast cell tumor) may lead to alteration of certain parameters, specifically elevated liver enzymes and kidney values or altered protein and electrolyte levels consistent with gastrointestinal involvement.  Solid tumors that spread internally can also cause similar abnormalities.  That being said, many patients with cancer (even when diffuse) will have a completely normal chemistry panel, and often, cancer patients will exhibit abnormalities (such as elevated liver/kidney values) that are unrelated to the cancer.  In these situations, advanced imaging (such as ultrasound and/or CT scan) will be recommended to search for structural defects in organs that can be aspirated (or biopsied) and submitted for cytology (or histopathology). 

In addition, evaluation of internal organ function is essential prior to administration of any chemotherapeutic agent.  A variety of chemotherapeutic agents are metabolized and/or excreted by the liver or kidneys, so it is important to know if these organs are abnormal prior to giving certain drugs.