observe either enzymes that are native to normal tissue or those that
could be associated with changes in metabolism that are unique to
This enzyme is
found in high concentraitions in the normal prostate as well as in
primary and metastatic prostate cancers. Acid Phosphatase may also
originate from other tissues.
sensitive immunological test (RIA or counterimmunoelectrophoresis for
prostatic acid phosphatase, wich are specific for the enzyme of
prostate tissue) often gives positive results in the early stages of
Because of the
reliability of acid phosphatase as a marker in early disease, it was
hoped that the test could be used as a screening tool. However, it may
also be elevated in up to 6 percent of cases of benign prostatic
hypertrophy and other conditions. Thus, its predictive value is low on
theoretical grounds. So, acid phosphatase is useful in following
patients with advanced disease.
enolase is an isozyme of the glycolytic pathway that is found only in
brain and neuroendocrine tissue. Its an immunohistochemical marker for
tumors of the central nervous system, neuroblastomas, and APUD tumors.
Use of NSE has
been evaluated in lung cancer and neuroblastoma
Transferase II, an isozyme of galactosyl transferase, has been shown
to be elevated in a variety of malignancies, predominantly
gastrointestinal. In colon cancer its level correlated with the extent
of disease and disease progression; in pancreatic cancer it was more
sensitive and specific in distinguishing benign from malignant disease
than CEA and other tests.
Production of a
monoclonal immunoglobulin molecule is characteristic of multiple
myeloma. These paraproteins are usually complete antibody molecules
but may be isolated light chains or, rarely, heavy chains. They may be
lambda or kappa light chains and of any immunoglobulin subtype.
are valuable in the staging and treatment of myeloma, the amount of
paraprotein serving as an index of tumor volume. Response to treatment
is indicated by a fall in paraprotein production, whereas a rise
points to relapse.