The concept of tumor markers and history

Date：2013-09-16

   The tumor is loss of the normal biological control abnormal growth and differentiation of cells and tissues. And other diseases compared to the tumor with two distinct clinical characteristics: First, the transfer characteristics of the tumor . Second, the early and middle tumors are asymptomatic. Early detection, early diagnosis, early treatment is the treatment of tumors of national policy. For asymptomatic cancer patients , tumor markers often the only clues to early detection of cancer .

    First, the history of the development of tumor markers

    1847 , from boiled acidified urine protein precipitation and found Bence Jones protein (Bence-Jones protein). Bence Jones proteins have now been recognized as a sign of multiple myeloma .

    History of the development of tumor markers can be divided into four broad phases: the first phase, in 1846 -1928 years , discovered Bence Jones protein ; Stage 1929 - 1962 , found that some hormones , enzymes, isoenzymes and protein when an exception occurs in the tumor , and some are still used in Journal of Clinical Oncology ; phase III 1963 - 1975 , discovered the embryo protein markers , this period to discover fetoprotein (α-fetoprotein, AFP) and carcinoembryonic antigen (carcioembryonic antigen , CEA) as the main feature , the discovery of these two signs to promote the clinical application of tumor markers , tumor markers for cancer diagnosis begins , treatment monitoring ; fourth stage since 1976 , a large number of tumor markers with monoclonal antibody technology birth and emergence of many cancer cells produce substances have the appropriate antibodies, such as CA15-3, CA125 and so on. Over the past decade , the development of molecular biology techniques enable determination of oncogenes, tumor suppressor genes become routine work , tumor markers into the molecular level .

    Second, the concept of tumor markers

( A ) Definition of tumor markers

    Tumor markers characteristic is present in the tumor cells or by the abnormal malignant cells or substances produced by the reaction of a host of substances produced by the tumor . These substances present in tumor cells and tissues may also enter the blood and other body fluids , when the cancer development , these substances obvious abnormalities , marked tumor.

    Most of the tumor markers in body fluids that existing tumors , but also in the normal population and the non- cancer patients, cancer patients is higher than the concentration of a marker for cancer patients . Only a handful of PSA and several other tumor markers associated with specific organs and organ-specific presentation , the majority of tumor markers in a variety of tissue types of cancers were positive , but the positive rate varies .

    Except for a few tumors , most tumors tend to have more positive tumor markers positive. A particular tumor , different tumor stages , different tumor cell types, different prognosis , the positive tumor markers may vary ; or identical positive sign different rates , increasing the tumor marker application complexity . Some tumor markers were positive in a variety of tumors , called broad-spectrum tumor markers (nonspecific tumor marker).

( Two ) the ideal tumor marker

    Ideal tumor marker should meet the following conditions: ① high sensitivity ; ② high specificity ; ③ concentration of tumor markers and tumor size , flag half-life is short, effective treatment soon after the fall , reflecting the rapid in vivo tumor the actual situation ; ④ concentration of tumor markers and tumor metastasis, degree of malignancy , can help determine tumor staging and prognosis ; ⑤ present in body fluids especially easy to detect in the blood . Unfortunately, so far all of the one hundred kinds of tumor markers in only a few a few signs to meet the above requirements, satisfactory for clinical use.

( Three ) the classification of tumor markers

    Tumor markers wide variety of sources , it is customary according to the nature of the sign itself , tumor markers into the following seven categories:

① enzymes and isoenzymes ;

② hormone ;

③ embryonic antigen ;

④ protein ;

⑤ glycoproteins ;

⑥ genetic markers ;

⑦ Other tumor markers .