Tumor Measured and evaluated as indicator of normal

Tumor marker

 Tumor: 
Cancer is abnormal cell growth with the potential to invade or spread to
other parts of the body.

 Biomarker:

Measured and evaluated as indicator of
normal biological process or a pathogenic process, or a pharmacological
response to a therapeutic intervention.

 Characteristic of Ideal biomarker

  
expression should significantly increase in disease condition

 
Readily quantifiable in clinical sample

 
It should be economically viable

 Tumor marker

 It  is a
Biochemical substances produced by cancer cell or by the healthy cell

It’s a Substances  found at higher level than normal level  in cancerous condition, which differentiate
the normal cell from cancer cells 

Tumor marker seen in: Blood circulation, Body cavity fluids
Cell membrane, Cell cytoplasm

Tumor
marker  classification :

                 
i.           
Tumor
Specific Antigens  -Specific for
single individual tumor, present only in tumor cells           Ex:CEA,CA19-9,CA125

              
ii.           
Tumor-Associated
Antigens are Found with different tumor of same tissue type Present
on tumor cells and some normal cells Expressed at abnormal concentration when
presence of cancer                       
Ex: Prostate specific antigen, Beta HCG,AFP L3,thryglobin

           
iii.           
Enzyme- 1st
group identified as a biomarker           
ex:ALP

            
iv.           
Hormone used
to detect and monitor the cancer     
ex:ACTH

               
v.           
Onco-fetal
protein -anti-sera against cancer          
ex:AFP,CEA,PSA

            
vi.           
Tissue cell
surface antigen- Blood group Ag using monoclonal antibody detect cancer
cell                                        
ex: CA 125,CA15-3,CA19-9

According to
site tumor marker classification:

a.     Biochemical /serological marker:

b.     detected in blood or body fluids

c.      histochemical/ tissue marker- found in tissue by
immunological test

d.     diagnostic marker

e.     prognostic marker/ predictive marker

f.       therapeutic marker

 clinical use :

     Screening

     diagnosis

    prognostic
predictor              

    clinical
staging of the cancerous condition              

   monitoring
during treatment

  
early detection for recurrence

CHARACTERISTICS
OF AN IDEAL TUMOUR MARKER

         Should not be very costly                sensitivity,

        Specificity                                          
accuracy

        Precision                                           
simple to use

Tumor markers:

CEA (carcino embryonic antigen)–Lung
cancer, breast cancer, Colorectal cancer

alfa feto protein -Hepato cellular carcinoma, Germ cell tumor, HCG(human chorionic gonodotrophin)

human
chorionic gonodotrophin(HCG)- Germinal 
cell tumor of  testis, Ovarian adenocarcinoma,
Hepatoma, chorio carcinoma

 CA 125- Ovarian
carcinoma

calcitonin – Medullary thyroid cancer

 CA15-3/ CA27.29 –  Breast
cancer, Liver cancer, colon cancer, ovarian endometrial cancer

 Prostate specific antigen -Prostate cancer

 Thyroglobulin –Thyroid cancer

 21-Gene
signature(oncotype-Dx), 70-Gene signature(mammaprint) & Estrogen
receptor/ progesterone receptor -Breast cancer

 Cytokeratin 
fragments21-1- Non small
cell Lung cancer,breast cancer,

Insulin-Insulinoma(beta
cell tumor)

Cortisol/ACTH- Equine pars intermedia adenoma, adreno cortical
tumor

Beta 2
microglobulin(B2M) -multiple myeloma,Chronic
lymphocytic leukemia PTHrP- Adenocarcinoma of
anal sac,lymphoma

 Chromogenin A(CgA) /parathyroid secretory protein

sex steroid
hormone-Adeno carcinoma

HE4 -Ovarian cancer

CD20- Non-hodgkin
lymphoma

 Prostatic
acid phosphate – Prostate cancer,myeloma   

Thymidine kinase – Breast cancer,Non
hodgkin’s lymphoma,Multiple myeloma

ALP- Metastatic bone,
liver,lung,ovary, uterus cancer

 Methods of detection of tumor marker:

      
I.           
Immunological
method:

              Immuno histochemistry

             Radioimmuno assay

             ELISA

  
II.           
Cytogenetic
analysis

     Fluorescent insitu hybridization(FISH)

    Spectral karyotyping

    Comparative genomic hybridization

   

III.           
Genetic
analysis 

        Sequencing

       Gel electrophoresis

 IV.           
proteomics

       Surface 
enhanced laser desorption/ionization

IMMUNOHISTOCHEMISTRY- By linking the antibodies to a dye, The immunoreactivity between the tissue specimens
and antibodies can be visualized with the light microscope

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