Tumor marker Flashcards
What is the primary function of testing Tumor marker? (1)
Give examples that Tumor marker is used for screening (3), diagnosis (3), and disease progression (3)
Most are for treatment & recurrence monitoring
Screening:
hCG(testicular cancer), Calcitonin(thyroid medullary), & PSA(prostate cancer)
Diagnosis:
insulin, gastrin, prolactin, CAT
Disease progression:
BRCA-1, Estrogen R, Progesterone R, cathepsin-D, Ph chr
Name four Gene tumor markers (4)
Name two tumor suppressor gene (2)
retinoblastoma gene (RB gene)
Ph
Myc
p53 gene
BRCA
p53
hCG is a Hormone tumor markers. Why IMA for hCG has Antibody targeting both intact & free β hCG? (1) Why hCG sometime increase after chemotherapy? (1) Suggest another marker that have synergistic effect in testicular cancer screening with hCG. (1)
In recurrence of testicular cancer, there is production of β-subunit without intact hCG
Slightly increase after chemotherapy due to tumor cell destruction
AFP, 70% for nonseminoma testicular cancer
Name 6 Enzyme tumor markers (6)
CK-BB
GGT
AMY
Placental ALP
ALP & LDH
RB gene
Missing = retinoblastoma
Mutation = various cancer
Ph
CML, AML & ALL
Myc
lung, breast, colon, stomach, leukemia, and lymphoma
tested on tissue instead of blood
CK-BB
prostate cancer and SCLC
GGT
Hepatoma
AMY
Pancreatic cancer
cancer monitored by Placental ALP (1)
Name 1 additional test to confirm lung cancer
Lung cancer, confirm in patient with Cushing syndrome caused by ectopic ACTH production
Is ALP & LDH tumor markers? (1)
Yes, high ALP & LDH suggests various tumors
Name 7 oncofetal antigen tumor markers (7)
AFP, CEA, PSA, CA125, CA153, CA199, SCCA
cancer monitored by AFP (1)
Is it possible that other condition causes high AFP making it an invalid marker for cancer monitoring? (2)
Liver cancer (80%), yolk sac, testicular
usually >10X
Other than liver cancer, consider ovarian, testicular, breast, GI, and bladder cancers. Monitoring recurrence of liver cancer may not be valid in patient with multiple cancers.
cancer monitored by CEA (1)
Can I use CEA for screening purpose? (2)
Colon cancer, also in breast, lung & stomach
For screening, use OB (80%), not CEA (60%), not AFP (5%)
cancer screened by PSA (1)
Can a patient with that cancer has normal PSA? (2)
Is patient with high PSA means he has that cancer? (2)
At what levels of PSA would you recommend prostate biopsy? (2)
Prostate cancer
Yes, a cutoff of 4 ng/mL gives 60% sensitivity only, so patient having Prostate cancer is not always detected by PSA, although it is called a screening test
No, a high PSA specificity for Prostate cancer is 60% only, because PSA also increase in patient with Benign prostatic hyperplasia (BPH)
PSA > 10 ng/mL OR fPSA < 25%
In patient with prostate cancer, fPSA/total PSA ratio drops due to incomplete cleavage of PSA
SCCA
Uterine cancer
Value of SCCA for diagnosis & prognosis remain controversial
CA125
Ovarian cancer
CA153
breast cancer
Describe how Cathepsin-D, ER / PR, HER-2/neu (c-erb B-2 gene), and EGF-R helps in determining the prognosis of breast cancer (4)
High Cathepsin-D suggest higher chance of relapse
ER / PR + suggests responsiveness to tamoxifen therapy
ER- / PR+ = 15%
ER+/ PR+ = 75%
HER2 + suggests responsiveness to Herceptin therapy
EGFR+ suggests poor prognosis in general
What is the difference between tamoxifen therapy & Aromatase inhibitor? (2)
tamoxifen targets ER while Aromatase inhibitor targets E
Aromatase inhibitor is recommended for postmenopausal women as it is 30% more effective, and E alteration has less toxic effect for them.
CA199 (1)
Why some people have 0 CA199 regardless of cancer existence? (1)
Gastric, pancreatic, and colorectal cancer
CA199 is always Negative in Le(a-b-) phenotype as Le enzyme is required for CA199 synthesis
Urine VMA, catecholamines, and metanephrines
Pheochromocytoma & neuroblastoma
Chromogranin A
pheochromocytoma, neuroblastoma, and carcinoid tumors
Urine 5-hydroxyindoleacetic acid (5-HIAA)
carcinoid tumors
Urinary HVA
Neuroblastoma (75%)
Not in pheochromocytoma
