Transcript Tumor Markers

Tumor Markers
American cancer society
British Journal of Cancer
By B.Heidari
What are tumor markers?
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substances that can be found in the body when cancer
is present
Classic : protein in the blood in higher than normal
Some : in urine or other body fluid others are found in
tumors and other tissue
Most tumor markers are proteins, but some newer
markers are genes or other substances.
In one type of cancer-in many types of cancer
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Sample : blood-urine-piece of the tumor
Tumor markers alone are rarely enough to show
that cancer is present !
tumor markers -> patient’s history, physical
exam, other lab tests or imaging
How are tumor markers used?
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Screening and early detection of cancer
Diagnosing cancer
Advanced cancer
Determining prognosis for certain cancers
Seeing if certain treatments are likely to work
Seeing how well treatment is working
Looking for recurrent cancer
Specific tumor markers
The tumor markers listed here are available to
most doctors and have reliable scientific
information showing that they are useful.
CA 19-9
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was first developed to detect colorectal cancer
most often used in : pancreatic cancer
In very early disease the level is often normal, so it’s
not good as a screening test
Still, it’s the best tumor marker for following
patients who have cancer of the pancreas.
Normal blood levels below 37 U/mL
elevated in cancer bladder – colorectal – stomach
- bile ducts
non-cancerous conditionsthyroid disease,
rheumatoid arthritis, inflammatory bowel disease,
and pancreatitis
CA 125
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standard tumor marker used to follow epithelial ovarian
cancer
Normal blood levels below 35 U/mL
More than 90% of advanced ovarian cancer have high levels.
Levels are also elevated in about half of women whose
cancer has not spread outside of the ovary screening test
Trouble : miss many early cancers & problems other than
ovarian cancer(uterine fibroids or endometriosis)
elevated in cancerlung, pancreatic, breast, liver, and colon,
cancer in the past
ovarian cancer is arather rare diseaseincreased CA-125
level something other than ovarian cancer.
CEA
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(Carcinoembryonic antigen)
CEA is not used to diagnose or screen for
colorectal cancer, but it’s the preferred tumor
marker to help predict outlook.
Normal blood levels below 5.5 ng/mL
standard marker :responding to treatment,
recurrency
elevated in cancerlung, breast,melanoma,
lymphoma, thyroid, pancreas, liver, stomach,
kidney, prostate, ovary, cervix, bladder
non-cancerous diseaseshepatitis,COPD, colitis,
rheumatoid arthritis, and pancreatitis, healthy
smokers
HER2
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(or HER2/neu, erbB-2, or EGFR2)
is a protein that tells some cancer cells to grow
Elevate in breast cancer cells in about 1 out of 5 people
with breast cancer
elevated in cancerstomach, esophagus
Sample:tissue
HER2-positive:grow and spread faster than other
cancers -> respond to drugs that work against the HER2
receptor
All newly diagnosed breast cancers and advanced
stomach cancers should be tested for HER2
P53
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(BCC7; LFS1; TRP53 )
nuclear phosphoprotein functions as tumor
suppressor by inhibiting cell proliferation
dominant role in cellular apoptosis
P53 gene mutations : 50% of all types of cancers
Commonly :primary breast , colon, ovarian,
lung, and esophageal carcinomas
Ki-67
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cancer antigen that is found in growing,
dividing cells but is absent in the resting phase
of cell growth
a good response to chemotherapy
sample :tumor tissue
high levels : aggressive tumor and predict a poor
prognosis , the risk of recurrence
elevated in cancerbreast, bladder, brain, colon,
prostate
The End