Question 1

Which of the following factors is necessary for local tumor spread?

Accepted Answer

Increased cellular motility is necessary for local tumor spread as it allows tumor cells to break away from the primary tumor and invade surrounding tissue. Increased cell adhesion would actually inhibit local tumor spread as it would keep tumor cells attached to the primary tumor. Temporary cessation of cell division would not contribute to local tumor spread, and the presence of lymphatic vessels is more related to metastasis than local tumor spread.

Question 2

In cancer, angiogenic factors stimulate:

Accepted Answer

In cancer, angiogenic factors stimulate new blood vessel growth to support the tumor's nutrient and oxygen needs.

Question 3

A 40-year-old female was diagnosed with colorectal cancer, for which she refused treatment. Four years later she returned to her physician. Testing revealed that the cancer had metastasized to the:

Accepted Answer

Colorectal cancer commonly metastasizes to the liver. While it is possible for it to metastasize to other organs such as the brain, lungs, and bones, the liver is the most common site of metastasis in colorectal cancer.

Question 4

A physician is attempting to diagnose cancer and is looking for a tumor marker. Which of the following could be a possible marker?

Accepted Answer

Enzymes, particularly those that are overexpressed or abnormal in cancer cells, can be used as tumor markers to aid in cancer diagnosis. Red blood cells, apoptotic cells, and neurotransmitters are not typically used as tumor markers.

Question 5

Presence of telomere caps gives cancer cells:

Accepted Answer

Telomere caps give cancer cells immortality by preventing the shortening of telomeres with each cell division, which is a natural aging process in normal cells.

Question 6

A 25-year-old male develops a tumor of the breast glandular tissue. This type of tumor is classified as a(n):

Accepted Answer

A tumor of the breast glandular tissue is typically classified as an adenocarcinoma, which is a cancer that originates from glandular cells. Carcinoma (A) is a general term for cancer that arises from epithelial cells, which includes glandular cells. Sarcoma (C) is a cancer that originates from connective tissue cells, and lymphoma (D) is a cancer that involves the lymphatic system.

Question 7

A 50-year-old female develops skin cancer. One potential reason for development of this condition is:

Accepted Answer

Skin cancer is often caused by mutations of caretaker genes, which are responsible for repairing DNA damage and preventing the accumulation of mutations that can lead to cancer. Heterozygosity for genetic markers and silencing of an oncogene are less commonly associated with the development of skin cancer. DNA methylation can play a role in cancer development, but it is not necessarily specific to skin cancer.

Question 8

The process by which a cell acquires specific new observable characteristics is:

Accepted Answer

The process by which a cell acquires specific new observable characteristics is called differentiation. This involves the expression of certain genes and the suppression of others, leading to the development of different types of cells with specific functions. Commitment refers to the decision of a cell to become a specific type of cell, while commutation refers to a change in the frequency or intensity of a signal. Consanguination refers to the mating between closely related individuals.

Question 9

A 52-year-old male with hepatitis C recently developed hepatic cancer. Which of the following markers should be increased?

Accepted Answer

Alpha-fetoprotein is a tumor marker for hepatic (liver) cancer. A rise in its level is seen in the majority of cases with hepatocellular carcinoma (HCC), especially in advanced cases. Hepatitis C is a common risk factor for developing HCC. Choice B is incorrect because catecholamines are not related to liver cancer. Choice C is incorrect because prostate-specific antigen is a marker for prostate cancer, not liver cancer. Choice D is incorrect because homovanillic acid is a metabolite of dopamine that is a marker for neuroendocrine tumors, not liver cancer.

Question 10

A patient has a tissue growth that was diagnosed as cancer. Which of the following growth types could it be?

Accepted Answer

Neoplasm is a general term for any tissue growth that is abnormal and can be benign or malignant, including cancer. Lipoma is a benign growth of fatty tissue, meningioma is a benign growth of the meninges (tissue covering the brain), and organ hypertrophy is an increase in the size of an organ due to an increase in the size of its cells.

Question 11

A proto-oncogene is best defined as:

Accepted Answer

A proto-oncogene is a normal gene that regulates cell growth and division, but when mutated or overexpressed, can lead to the development of cancer.

Question 12

Which feature is characteristic of malignant tumor?

Accepted Answer

A high mitotic index indicates that the cells are dividing rapidly, which is a characteristic of malignant tumors. Options A, B, and D are all features more commonly associated with benign tumors.

Question 13

Of the following genetic lesions that cause cancer, which is the most common?

Accepted Answer

Point mutations, or changes in a single base of DNA, are the most common genetic lesions that cause cancer. They can alter the function of important genes involved in cell growth and regulation, leading to uncontrolled cell growth and tumor formation. Insertions, deletions, and amplifications can also contribute to cancer development, but they are less frequent than point mutations.

Question 14

When a cancer cell loses differentiation, _____ has occurred.

Accepted Answer

Anaplasia is the loss of differentiation in cancer cells, where the cells lose their specialized features and morphological characteristics. Autonomy refers to the ability of cancer cells to divide and proliferate independently, while pleomorphism refers to the variable or irregular shape and size of cancer cells. Metastasis refers to the spread of cancer cells from one part of the body to another.

Question 15

A 45-year-old female was recently diagnosed with cervical cancer. She reports a sexual history that includes 43 partners. Which of the following is the most likely cause of her cancer?

Accepted Answer

Human papilloma virus (HPV) is the most common cause of cervical cancer. Having multiple sexual partners increases the risk of exposure to different types of HPV, which can lead to cellular changes and the development of cervical cancer over time. Herpes virus, rubella virus, and hepatitis B virus are not typically associated with the development of cervical cancer.

Question 16

Preinvasive epithelial tumors of glandular or squamous cell origin are referred to as:

Accepted Answer

Preinvasive epithelial tumors of glandular or squamous cell origin are referred to as cancer in situ, meaning the cancer cells have not yet invaded into the surrounding tissue. Choices A, B, and D do not accurately describe this type of tumor.

Question 17

A 45-year-old male presents with persistent, severe stomach pain. Testing reveals a peptic ulcer. Further laboratory tests reveal the presence of Helicobacter pylori. Which of the following is of concern for this patient?

Accepted Answer

The presence of Helicobacter pylori is a risk factor for the development of gastric cancer. While peptic ulcers are rarely malignant, the presence of H. pylori increases the risk of gastric cancer. Leukemia, lung cancer, and adenocarcinoma of the colon are not directly related to the presence of H. pylori or peptic ulcers.

Question 18

The best explanation for higher rates of cancer in older populations is:

Accepted Answer

Cancer typically requires multiple genetic mutations to develop, and these mutations accumulate over time, making older individuals more susceptible to cancer.

Question 19

A 30-year-old American male with HIV is diagnosed with Epstein-Barr virus. After 2 months, the virus is still active. What is the concern for this patient?

Accepted Answer

HIV-positive individuals are at an increased risk for certain cancers, including B cell lymphomas, as the Epstein-Barr virus can cause the proliferation of B cells. If the virus remains active for an extended period, there is a higher risk of the development of B cell lymphoma. Burkitt lymphoma is a specific subtype of B cell lymphoma that is associated with Epstein-Barr virus infection, but it is not the most common concern for this patient. T cell leukemia and lymphoma are not typically associated with Epstein-Barr virus infection.

Question 20

A child develops retinoblastoma. Which of the following must have occurred?

Accepted Answer

Retinoblastoma is caused by mutations in both copies of the rb gene, which is a tumor suppressor gene. When both copies are mutated, the cell loses its ability to regulate cell division and tumors can form. Activation of the rb gene or the apoptosis gene would not directly result in retinoblastoma, and only one mutation in the rb gene would not be enough to cause the disease.

Quiz 9: Biology of Cancer and Tumor Spread