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.

The more 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 disease.

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.

Neuron Specific Enolase

Neuron specific 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

Galactosyl Transferase II

Galactosyl 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.

Immunoglobulins

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.

Immunoglobulins 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.