Cancer Biomarkers

In the era of personalized medicine and targeted therapies, cancer biomarker testing has an important role. Pathologists should have a good knowledge about this field and be up to date. Pathologists need well-defined guidelines for cancer biomarker testing and interpretation. Of course, these guidelines should be in concordance with oncology and other fields involved in cancer management and treatment.What is a cancer biomarker There is a simple definition in Wikipedia: A cancer biomarker refers to a substance or process indicating the presence of cancer in the body . Cancer biomarkers estimate the risk, diagnostic, screening, differential diagnosis, prognostic, predictive and more important therapeutic decision role (1).Cancer biomarker may be a serum protein or antibody, a fragment of gene, or a genetic or epigenetic alteration. The definition of National Cancer Institute (NCI) for biomarker is: A biological molecule found in blood, other body fluids, or tissue that is a sign of a normal or abnormal process, or of a condition or disease. A biomarker may be used to see how well the body responds to a treatment for a disease or condition. It is also called molecular maker and signature molecule (2).Number and type of biomarkers are growing, so reference laboratories and scientific societies have an important role in standardization of these tests from sampling to reporting. In pathology labs, fixation and processing of tissues are very important, so the suitable time for fixation before processing should be determined and even included in final report. One of the oldest and well-known serum biomarkers is PSA in prostatic carcinoma. Now there are many serum tumor markers for prostatic carcinoma.The first tissue biomarkers we know were found in breast pathology. Determination of hormonal receptors in breast cancer nowadays is a routine work in many pathology laboratories. For ER, PR, and HER2 testing and reporting, there are well-defined guidelines (3, 4). The CAP has a protocol and template for reporting breast biomarkers (5). Other biomarkers in breast field include ki-67, P 53, PTEN, PIK3CA, STAT3, BRCA-1 and BRCA-2, and molecular platform for determination of risk of recurrence and response to treatment.

Keywords:

Cancer , Biological Markers , Guideline