EKUSILENI CLINICAL LABORATORY

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EKUSILENI CLINICAL LABORATORY

• PSA AND CEA AS SURROGATE MARKERS FOR CANCER
  DIAGNOSIS
• TALENTS MURAHWA
• (BIOMEDICAL SCIENTIST)

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LAB CANCER MANAGEMENTWhat are tumor markers

• Definition -
• A tumour marker is a biochemical indicator
  selectively produced by the neoplastic tissue and
  released into blood and detected in blood or in
  other body fluids.
• It may be used to -
• Detect the presence of a tumour
• Monitor the progress of disease
• Monitor the response to treatment

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Tumour Markers - Classification

• Class 1 Antigens unique to a neoplasm not
  shared by other tumours of same histological type
  .
• Class 2 Antigens expressed by many or most
  tumours of a specific histological type and of
  other histological type,
• But not expressed by normal adult tissue.
• Class 3 Antigens expressed by both cancer and
  normal adult tissue.

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NATURE OF TUMOUR MARKERS

• 1.Oncofetal antigens
• Alpha Feto Protein
• CEA
• Pancreatic Oncofoetal Antigen
• 2.Proteins
• Casein By breast carcinoma
• Ferritin- Leukaemia
• 3.Enzymes
• Creatinekinase Prostate tumour
• Alkaline Phosphatase Lungs tumour
• Acid Phosphatase Prostate tumour

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• Receptors
• Oestrogen, Progesterone, Androgen
• Polyamines
• Spermine, Spermidine, Putridine leukemia,
  lymphoma, colorectal CA
• Cell Markers
• T cell marker, B cell marker-lymphoma
• Ectopic Hormones
• HCG, GH, Erythropoetin, Renin

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• LOCAL LABORATORY TESTS ON OFFER
• 1.Alfa Feto Protein
• 2.CEA
• 3.PSA
• ALPHA AMYLASE
• LDH

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Alfa Feto Protein-

• Measurement of maternal serum and amniotic fluid
  levels play an important role in the screening
  for
• Foetal neural tube defects
• Chromosomal abnormalities including Downs
  Syndrome.
• Most measurements are done at 16 weeks of
  gestation.
• Raised maternal serum AFP levels are not specific
  for neural tube defects.
• Must be used in combination with other modalities
  such as USG, amniotic fluid AFP and acetylcholine
  esterase.

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Alfa Feto Protein-

• Many fetal conditions are associated with
  abnormal maternal serum AFP levels.
• Elevated
• NTD, GI obstruction, Liver necrosis, Abdominal
  wall defects (Omphalocele, Gastroschisis),
  Sacrococcygeal tumour, Cystic hygroma, IUGR,
  multiple pregnancies, renal anmalies.
• Low
• Chromosomal trisomies (Downs syndrome),
  Gestational trophoblastic diseae, IUD, placental
  defects, GA underestimated, Foetal distress,
  Hydrops Foetalis, TOF, Cyclopia.

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Alfa Feto Protein-

• After birth AFP usually falls, within 8 to 12
  months of delivery to a very low conc.of 10mcg/ml
  and persists at this low level throughout life.
• Unexplained and persistent elevation of AFP in
  nonpregnant state should be screened, as it may
  be due to-
• Hepatocellular Ca, germ cell tumour, hereditary
  persistence of AFP, viral hepatitis and cirrhosis
  .
• In addition to its role in prenatal diagnosis, it
  is also widely used in the diagnosis, therapeutic
  monitoring and follow up of patients in germ cell
  tumours.

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Germ Cell Tumours Producing AFP

• AFP
• Dysgerminoma --
• Endodermal Sinus tumour /
• yolk sac tumour
• Immature tetratoma /-
• 4. Mixed germ cell tumour /-
• 5. Choreocarcinoma --
• 6. Embryonal CA --

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CEA-

• It is a glycoprotein of mol.wt 200kda.
• Though it is a tumour marker for GI cancers, it
  is also expressed by
• malignant mucinous tumor (100),
• 100 cases of atypical hyperplasia of
  endometrium,
• 60 cases of endometrial Ca,
• 50-80 cases of squamous cell of Cx,
• 75-100 cases of adenocarcinoma of Cx.
• It is also produced in pneumonia, hypothyroidism
  and pancreatic tumours.

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PSA

• Prostate-Specific Antigen (PSA)
• A prostate-specific antigen (PSA) test measures
  the amount of prostate-specific antigen in the
  blood. PSA is released into a man's blood by his
  prostate gland.

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• Healthy men have low amounts of PSA in the blood.
  The amount of PSA in the blood normally increases
  as a man's prostate enlarges with age. PSA may
  increase as a result of an injury, a digital
  rectal exam, sexual activity (ejaculation),
  inflammation of the prostate gland (
  prostatitis), or prostate cancer

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PSA Why is it done?

• Why It Is Done
• The prostate-specific antigen (PSA) test is done
  to
• Monitor prostate cancer and how it responds to
  treatment. If PSA levels increase, the cancer may
  be growing or spreading. PSA is usually not
  present in a man who has had his prostate gland
  removed. A PSA level that rises after prostate
  removal may mean the cancer has returned or has
  spread.

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PSA

• Prostate cancer often grows very slowly, without
  causing major problems. Detecting prostate cancer
  early and treating it may prevent some health
  problems and reduce the risk of dying from the
  cancer. However, some treatments for prostate
  cancer can cause other problems, such as

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PSA

• Determine if cancer may be present when other
  tests, such as a digital rectal exam, are not
  normal. A PSA test does not diagnose cancer, but
  it can be used along with other tests to
  determine if cancer is present.

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PSA

• Check men for prostate cancer. Experts disagree
  on the usefulness of PSA testing as a screening
  tool for prostate cancer. If a PSA test is used
  for screening, it is usually done for men older
  than age 50 or for those at high risk for
  prostate cancer, such as men with a family
  history of prostate cancer, or for
  African-American men who have a higher chance of
  developing cancer than other men. Since other
  common medical conditions, such as prostatitis,
  can cause high PSA levels, a prostate biopsy is
  needed to confirm a diagnosis of cancer.

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CONCLUSIONTM cannot be
NECESSARILY constructed as primary modalities for
diagnosis of tumours THANK YOU