Deck 20: Tumor Markers and Cancer Genes

Question 1

A physical agent,such as exposure to ultraviolet light for an extended period of time,or a biological agent,such as a virus,may cause cancer.These agents are referred to as:

A) tumor markers.
B) carcinogens.
C) tumor suppressors.
D) oncogenes.

Answer 1

carcinogens.

Question 2

Upon receipt of a test request for assay of human chorionic gonadotropin (hCG)on a 60-year-old male,you would:

A) refuse the request because hCG is a pregnancy test and not performed on men.
B) assume the physician wanted a prostate-specific antigen (PSA)test.
C) perform the test because hCG can be elevated in testicular germ cell tumors.
D) contact the physician.

Answer 2

perform the test because hCG can be elevated in testicular germ cell tumors.

Question 3

A 25-year-old married woman has developed unusual abdominal pain.Her mother died of ovarian cancer and she is concerned that she is developing the same disease.Her physician orders CA 125 and hCG analyses,both of which return with a moderately elevated value.How should the physician interpret these results?

A) The physician should inform the woman that she is pregnant and not to be concerned about the likelihood of ovarian cancer.
B) The physician should perform more laboratory testing and transvaginal ultrasonography to determine whether the patient has ovarian cancer or is just pregnant.
C) The physician should prepare for surgical removal of the ovaries based on the tumor marker values.
D) The physician should examine these tumor marker values to determine whether they fall within specific cutoff intervals for healthy,benign,or cancerous groups.

Answer 3

The physician should examine these tumor marker values to determine whether they fall within specific cutoff intervals for healthy,benign,or cancerous groups.

Question 4

Which one of the following tumor markers is not a carbohydrate-related tumor marker with its most important clinical use in the assessment of breast cancer recurrence?

A) CA 15-3
B) CA 549
C) CA 125
D) CA 27.29

Question 5

A translocation between chromosomes 9 and 22 produces the BCR-ABL fusion gene.This is the transforming event in 90% of individuals with chronic myelogenous leukemia (CML).Which one of the following statements regarding the protein product of this fusion gene is correct?

A) It is a nuclear phosphoprotein that deregulates DNA syntheses and increases cellular proliferation.
B) It is a cytoplasmic tyrosine kinase that activates a number of signaling pathways leading to growth and inhibition of apoptosis.
C) It is a mitotic control gene that allows cells to move through the cell cycle and contribute to the autonomous growth of cancer.
D) It interacts with other proteins,such as $\alpha$ - and $\beta$ -catenin,involved in cell-cell interactions in epithelial cells to form polyps.

Question 6

Activated forms of normal cellular genes are termed:

A) oncogenes.
B) proto-oncogenes.
C) pre-oncogenes.
D) oncofetal antigens.

Question 7

The primary clinical usefulness of assessing alpha-fetoprotein (AFP)as a tumor marker is for:

A) monitoring patients with pancreatic cancer.
B) assessing patients with colon cancer.
C) monitoring therapy in patients with liver cancer.
D) assessing chemotherapy response in patients with breast cancer.

Question 8

Follicular lymphoma occurs when the:

A) c-abl proto-oncogene and the BCR gene on a chromosome reciprocally translocate.
B) HER-2/neu gene is overamplified,causing excess p105 to be released.
C) c-myc gene becomes juxtaposed to the heavy-chain locus on chromosome 14.
D) bcl-2 gene on chromosome 18 is translocated to the immunoglobulin heavy chain locus on chromosome 14.

Question 9

An oncofetal antigen commonly used to assess recurrence of tumor growth following removal of a colon tumor would be:

A) CEA.
B) AFP.
C) CA 125.
D) cathepsin D.

Question 10

The loss of a gene that codes for a tumor suppressor protein would predispose certain cells to cancerous transformation and unchecked proliferation.This class of genetic alteration is referred to as:

A) point mutation.
B) aneuploidy.
C) translocation.
D) deletion.

Question 11

Which of the following is considered to be a nonspecific tumor-associated marker?

A) Prostate-specific antigen (PSA)
B) Alkaline phosphatase (ALP)
C) CA 125
D) Tumor suppressor genes

Question 12

Which of the following tumor markers is useful for monitoring germ cell tumors or placental tumors?

A) CEA
B) PSA
C) CA-19
D) hCG

Question 13

The properties of an ideal tumor marker include all of the following,except it should:

A) be able to distinguish between benign and malignant tumors.
B) be produced by tumor cells and detectable in body fluids.
C) not be present in healthy people.
D) be specific for a given type of cancer.

Question 14

A 35-year-old man has blood work done to assess his hypertension and weight gain.He has also felt fatigued and moody with some respiratory difficulties.His physical appearance indicates possible Cushing's syndrome and his physician obtains blood for lab analysis.The man's adrenocorticotropic hormone (ACTH)level is extremely elevated (>300 ng/L),but upon ultrasound analysis the adrenal gland appears normal.What might be the cause of the elevated ACTH?

A) Ectopic synthesis of ACTH by small cell lung carcinoma
B) Ectopic synthesis of ACTH by tumor of thyroid gland
C) Cross-reaction of ACTH with other analytes to produce a false increase
D) Normotopic production of ACTH by overactive adrenal gland

Question 15

An example of a blood group antigen that would be elevated in pancreatic cancer and is US Food and Drug Administration (FDA)approved as an aid in monitoring pancreatic cancer patients is:

A) CA 125.
B) CA 15-3.
C) CA 19-9.
D) PSA.

Question 16

Proteins found in normal fetal tissue and also in certain tumors are referred to as:

A) embryonic proteins.
B) tumor-associated antigens.
C) oncogenes.
D) oncofetal antigens.

Question 17

Tumor markers that are antigens located on the surface of tumor cells are called:

A) carbohydrate-related tumor markers.
B) cell surface tumor markers.
C) oncogenes.
D) paraprotein.

Question 18

A 49-year-old man visits his physician with complaints of back pain; urinary frequency,especially at night; and difficulty passing urine.Results of prostate-specific antigen analysis reveal a value of 2.0 µg/L.The physician diagnoses the problem as benign prostatic hyperplasia (BPH); however,because the man's father had prostate cancer,the physician wants to track this patient for possible prostate cancer development.Each year,the man's PSA value increases 0.5 µg/L.This increase indicates:

A) a normal increase in PSA over time with age and likely BPH.
B) an increase in PSA common to risk of prostate cancer.
C) an increase in PSA concomitant with development of male breast cancer.
D) the need for further studies including digital rectal examination and transrectal ultrasonography.

Question 19

An individual with a history of miscarriage visits her physician to discuss her positive hCG test done with a qualitative point-of-care device.The patient says she "feels pregnant" but wants to be certain.Following an ultrasound analysis,she is diagnosed with a germ cell tumor of unknown type.What two tumor markers are useful in classifying germ cell tumors?

A) CEA and AFP
B) AFP and hCG
C) hCG and CEA
D) CEA and CA 125

Question 20

Proto-oncogenes are present in the human genome to serve the function of:

A) virus suppressors.
B) repairmen of DNA.
C) regulators of cell growth and proliferation.
D) directors of apoptosis.

Question 21

One of the mutations that is found most frequently in cancers and can ultimately lead to colon cancer involves a:

A) translocation of the K-ras proto-oncogene to chromosome 14.
B) point mutation in the K-ras proto-oncogene.
C) frameshift mutation in the N-ras proto-oncogene.
D) large deletion in the N-ras proto-oncogene.

Question 22

A 65-year-old man has been diagnosed with prostate cancer and is being prepared for radiation therapy.His physician is concerned that the cancer may have metastasized to the patient's skeletal system.Which one of the following laboratory analytes would give this information to the physician?

A) ALP
B) Calcitonin
C) AFP
D) Growth hormone

Question 23

Most oncogenes are activated through:

A) dominant mutations.
B) loss of gene expression.
C) monosomy.
D) loss of function recessive mutations.

Question 24

Regarding predictive value models of a tumor marker analysis assay,receiver operating characteristic curves are most useful in assessing tumor marker analyses because:

A) single tests for the same analyte can be evaluated over different times.
B) they allow specific reference intervals to be determined for each tumor marker.
C) they can display performance of tests or markers over the entire range of decision levels.
D) they can serve as delta checks by assessing changes in an individual's tumor marker concentration over time.