Tumor Markers Flashcards

(52 cards)

1
Q

What produces tumor markers?

A

The tumor itself or as an effect of tumor on healthy host tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are tumor markers used for?

A
Screening
Diagnosis
Prognosis
Monitor therapy
Detect recurrence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

T/F: Most tumor markers are also present in normal, healthy tissue or benign conditions

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

T/F Specific quantity of a TM is more important than the rate of increase in determining a patient’s prognosis

A

False. Rate of increase (velocity) is more important.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Highest levels of TM seen when tumor _______

A

metastasizes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

3 things that make a good tumor marker

A
  1. Specific
  2. Absent in normal population
  3. Readily detectable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

4 categories of commonly used tumor markers

A
  1. Enzymes
  2. Proteins
  3. Hormones/hormone metabolites
  4. Oncofetal antigens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why is measuring B-2 microglobulin useful?

A

It’s found on the surface of nucleated cells. Measures cell turnover.
Used to monitor renal transplant patients for rejection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do we detect tumor makers?

A

Quantitative immunoassay

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the hook effect?

A

What happens when analyte exceeds analytical range. Labeled antibodies are saturated and a “sandwich” is not formed. This causes a reduction in signal as the concentration increases. The line plotted is curved, not linear.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How do we compensate for the hook effect?

A

Dilute the sample

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What may interfere with TM detection/measurement?

A

Icterus, lipemia, hemolysis
Cross-reacting antibodies
Carry-over (from reusable probe, etc.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is alpha-fetoprotein measurement used for?

A

Diagnosis and prognosis of hepatocellular carcinoma

Also seen in germ cell tumors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

AFP with beta-HCG can be used to classify & stage _______ cancer

A

testicular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Is AFP completely specific?

A

No- increases seen in pregnancy, liver disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What level of AFP is diagnostic of HHC in high-risk patients?

A

> 500 ng/mL (The higher, the worse)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

AFP is usually synthesized by the _____ _______

A

fetal liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is CEA (carcinoembryonic antigen) used to detect?

A

Relapse of colorectal cancer (after diagnosis has been made)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Is CEA useful as a screening test for colorectal cancer?

A

No- it is not tumor-specific; may be elevated in other conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

HCG is normally secreted by cells of _______ to prepare and maintain pregnancy

A

placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How is HCG used as a tumor marker?

A

Prognostic indicator of ovarian cancer
Diagnostic marker to classify testicular disease
Helps detect Gestational trophoblastic disease

22
Q

Prostate specific antigen (PSA) is only produced by…

A

epithelial cells of prostatic ducts in prostate

23
Q

What is PSA best used for?

A

Monitoring the progression of prostate cancer after therapy

24
Q

Why would we measure both total and free PSA?

A

Total PSA (measures free & complexed PSA): screen for & monitor prostate cancer

Free PSA: patients with malignancy may have lower free PSA

25
T/F Prostate cancer may be present at normal PSA concentration
True
26
What is CA-125 used to detect?
Ovarian cancer
27
Is CA-125 used to screen asymptomatic patients?
No. Although it may be used to screen high-risk patients (family Hx or prior Hx of ovarian cancer)
28
T/F CA-125 levels do not correlate with stage of cancer
False- they do correlate
29
CA-125 is only clinically accepted marker for ______ _______
Ovarian cancer
30
Can CA-125 be used to distinguish ovarian cancer from benign masses?
yes- benign masses don't secrete this tumor marker
31
What is CA 19-9 used for?
To differentiate between pancreatic cancer and other cancers Monitor treatment & recurrence
32
High levels of CA 19-9 correlate with.....
disease progression, outcomes
33
Is CA 19-9 useful as a screening tool?
No
34
What is CA 15-3 used for?
Monitoring breast cancer treatment and disease recurrence
35
Can 15-3 be used alone to come to a diagnosis?
No- needs to be combined with history, physical exam, imaging
36
Why are 19-9 and 15-3 not useful as screening tests?
Levels may be increased in other benign or malignant conditions. May also be up in healthy individuals.
37
How can an elevated CK level from cancer be differentiated from elevation due to MI?
MI will cause CK to increase and then decrease. | In cancer, CK will increase and remain elevated
38
What are useful protein markers? | What makes a good marker?
Albumin, transferrin, prealbumin Short half-life makes a better marker
39
If transport protein levels are decreased, how can we tell if this is from inflammation or malnutrition?
CRP- high in inflammatory conditions
40
T/F: Albumin levels can classify severity of malnutrition
True
41
Definition of Kwashiorkor
Chronic protein deficiency with adequate non-protein intake.
42
S/S of Kwashiorkor
low albumin, edema, hepatomegaly
43
Definition of Marasmus
Deficiency of calories with adequate protein intake
44
S/S of Marasmus
Severe reduction in body weight (thin with wasting muscles), normal albumin levels, edema is rare
45
Why is transferrin a better marker of protein depletion than albumin?
Shorter half-life
46
Transferrin in synthesized by the _________. It binds and transports _____ _______.
liver | ferric iron
47
Increased transferrin levels can indicate iron ________
deficiency.
48
Can transferrin be used to diagnose malnutrition?
Maybe
49
What are the main roles of pre-albumin?
Transport thyroxin and Vitamin A
50
What do levels of Pre-albumin <80 mg/dL indicate?
severe protein-calorie malnutrition
51
Pre-albumin levels can also be used to monitor _____ in diabetic patients with ulcers or post-op patients
healing
52
What is another name for pre-albumin?
Transthyretin