FIGURE 4-1

(A) NF-1

(B) NF-2

(C) p53

(D) PTEN

(E) RB

28. The two-hit hypothesis of oncogenesis proposed by Knudson explains the inherited and sporadic occurrence of which of the following tumors?

(A) Meningioma

(B) Neuroblastoma

(C) Retinoblastoma

(D) Schwannoma

(E) Wilms tumor

29. Inherited mutations in the APC/beta-catenin tumor suppression gene are associated with which of the following?

(A) Familial adenomatous polyposis coli (APC)

(B) Melanoma

(C) Osteosarcoma

(D) Ovarian carcinoma

(E) Pancreatic carcinoma

30. All of the following are true regarding a breast cancer associated with BRCA-1 except

(A) Along with BRCA-2 mutations, BRCA-1 mutations account for all cases of familial breast carcinoma

(B) BRCA-1 gene mutations are also associated with the development of ovarian carcinoma

(C) BRCA-1 gene mutations are not associated with development of sporadic breast carcinoma

(D) BRCA-1 is involved in the regulation of estrogen receptor activity

(E) The gene for BRCA-1 is located on chromosome 17

31. Many tumors stimulate the growth of host blood vessels (angiogenesis). All of the following are reasons why a tumor would promote angiogenesis except

(A) It facilitates metastasis

(B) It helps supply nutrients

(C) It helps supply oxygen

(D) It promotes apoptosis

(E) It stimulates the growth of the tumor with growth factor secretions

32. All of the following inhibit angiogenesis except

(A) Angiostatin

(B) Endostatin

(C) Thrombospondin-1

(D) Tumstatin

(E) Vascular endothelial growth factor (VEGF)

33. Invasion of the extracellular matrix by tumor cells is important in tumor infiltration and in gaining access to lymphatic and vascular spaces. All of the following are important steps in the process of tumor invasion of extracellular matrix except

(A) Attachment to matrix components

(B) Degradation of extracellular matrix

(C) Detachment of tumor cells from each other

(D) Migration of tumor cells

(E) Reaggregation of tumor cells

34. A tumor rich in matrix metalloproteinase 9 is best equipped to do which of the following

(A) Breakdown adipose tissue and cause fat necrosis

(B) Cleave type IV collagen

(C) Facilitate intravascular tumor aggregation

(D) Inactivate tumor cell mitochondria

(E) Loosen intercellular junctions

35. A 69-year-old woman presents with an elevated white blood cell count. Lymph node and bone marrow biopsies are performed. Genetic testing of the tumor demonstrates a t(9; 22) (q34; q11). The most likely diagnosis is

(A) Acute lymphocytic leukemia

(B) Burkitt lymphoma

(C) Chronic myeloid leukemia

(D) Follicular lymphoma

(E) Mantle cell lymphoma

36. Which of the following techniques allows one to obtain an expression profile of proteins contained in a particular tumor?

(A) DNA microarray

(B) Proteomics

(C) Pyrosequencing

(D) Reverse PCR

(E) Southern blotting

37. Loss of the p53 gene on chromosome 17p occurs at which stage of the adenoma–carcinoma sequence in colorectal cancer?

(A) Dysplastic foci → early adenoma

(B) Early adenoma → intermediate adenoma

(C) Intermediate adenoma → late adenoma

(D) Late adenoma → carcinoma

(E) Normal epithelium → carcinoma

38. The Ames test is used to test the mutagenic potential of a chemical carcinogen by examining the chemical’s ability to induce mutations in what organism?

(A) Methicillin-resistant Staphylococcus

(B) Salmonella typhi

(C) Salmonella typhimurium

(D) Staphylococcus aureus

(E) Staphylococcus epidermidis

39. You are concerned that a patient’s hepatic carcinoma might be related to an exposure to aflatoxin B1. This toxin is associated with which organism, which may grow on improperly stored rice, peanuts, or corn?

(A) Aspergillus fumigatus

(B) Hepatitis A virus

(C) Salmonella typhi

(D) Shigella dysenteriae

(E) Shigella flexneri

40. Exposure to UV rays of which wavelength are associated with the greatest risk of developing skin cancer?

(A) 200–240 nm

(B) 240–280 nm

(C) 280–320 nm

(D) 320–360 nm

(E) 360–400 nm

41. Which of the following cancers would most frequently be encountered in a person exposed to ionizing radiation?

(A) Bone cancer

(B) Gastrointestinal cancer

(C) Leukemia

(D) Lung cancer

(E) Thyroid cancer

42. A 38-year-old woman is diagnosed with invasive cervical squamous cell carcinoma. Which of the following human papilloma virus (HPV) types are least likely to be found in the tumor?

(A) 16

(B) 18

(C) 31

(D) 33

(E) 36

43. Which HPV proteins is involved with facilitating p53 degradation, resulting in a block in apoptosis and decreased p21 cell cycle inhibitor activity?

(A) E1

(B) E3

(C) E5

(D) E7

(E) E9

44. Epstein–Barr virus (EBV) has been implicated in the development of all of the following cancers except

(A) B cell lymphoma in HIV patients

(B) Burkitt lymphoma, endemic type

(C) Hodgkin lymphoma

(D) Medullary breast carcinoma

(E) Nasopharyngeal carcinoma

45. Which of the following molecules facilitates the entry of EBV in lymphoid cells?

(A) CD3

(B) CD4

(C) CD19

(D) CD20

(E) CD21

46. All of the following are mechanisms of human infection or transmission of human T-cell leukemia virus type 1 (HTLV-1) except

(A) Aerosolization

(B) Blood products

(C) Breast-feeding

(D) Needle stick

(E) Sexual intercourse

47. Which of the following mechanisms are employed by tumor cells to escape the host’s immune system?

(A) Antigen unmasking

(B) Counteract immunosuppression

(C) Decreased apoptosis of cytotoxic T-cells

(D) Increased expression of major histocompatibility complex (MHC) molecules

(E) Selective outgrowth of antigen-negative variants

48. All of the following may play a role in the development of cancer-related cachexia except

(A) Androgen receptor

(B) Interferon-gamma

(C) Interleukin-1

(D) Leukemia inhibitory factor

(E) Tumor necrosis factor

49. Secondary polycythemia vera associated with increased production of erythropoietin is associated with which tumor?

(A) Breast carcinoma

(B) Gastric carcinoma

(C) Hemangioblastoma

(D) Thymoma

(E) Uterine carcinosarcoma

50. A 46-year-old woman presents with metastatic carcinoma of unknown primary. On evaluation, she is noted to have elevated CA-15-3 level. The most likely site of origin of her cancer is

(A) Breast

(B) Colon

(C) Liver

(D) Pancreas

(E) Ovary

51. Elevated carcinoembryonic antigen (CEA) levels may be encountered in all of the following settings except

(A) Alcoholic cirrhosis

(B) Colorectal carcinoma

(C) Pituitary adenoma

(D) Smoking

(E) Ulcerative colitis

52. Hypertrophic osteoarthropathy and clubbing of the fingers is most likely to be associated with which malignancy?

(A) Bronchogenic carcinoma

(B) Melanoma

(C) Pancreatic carcinoma

(D) Renal carcinoma

(E) Uterine sarcomas

ANSWERS

1. (B) Choristoma.

Choristomas represent an ectopic rest of normal tissue. The presence of normal appearing adrenal cells in the capsule of the kidney would present an example of this entity. Hamartomas represent a mass of disorganized but mature specialized cells or tissue indigenous to a particular site. Adenoma is a term used to apply to benign epithelial neoplasms that form glandular patterns as well as benign tumors derived from glands that do not necessarily form glandular patterns, for example, parathyroid or pituitary adenoma. Hyperplasia represents an increase in the number of cells in an organ or tissue. Teratoma represents a benign tumor that is composed of a variety of parenchymal cell types representative of more than one germ layer and usually of all three layers. Teratomas typically arise from totipotent cells and most commonly arise in the ovaries or testes.

2. (D) Nuclear to cytoplasm ratio of 1:5.

Lack of differentiation or anaplasia is characterized by a host of morphologic alterations including abnormal nuclear morphology with increased nuclear to cytoplasmic ratio typically approaching 1:1 or less than 1:1 versus the normal nuclear to cytoplasmic ratio of 1:4–1:6. Increased mitoses including atypical figures are associated with lack of differentiation and anaplasia. Cells typically lose their normal orientation or polarity with loss of differentiation. Nuclear pleomorphism, that is, a variation in cell and nuclear size and shape, is a common feature associated with anaplasia.

3. (E) 30.

In the parameters presented, the transformed cell must undergo at least 30 population doublings to produce 10⁹ cells that would weigh approximately 1 g; this would result in a mass that could be grossly detected. Ten additional doublings would result in a mass that would be composed of 10¹² cells which would translate into a 1 kg tumor.

4. (A) Amount of collagen matrix in the environment.

There are a variety of factors that play an important role in determining the rate of growth of a tumor. Doubling time of tumor cells, the percent of tumor cells that are in the replication pool, and the rate at which cells are lost or shed in the growing lesion are important determinant factors. Certainly, the available nutrients and oxygen in the environment of the tumor would also impact on a variety of these aforementioned factors. The amount of collagen matrix in the environment would not significantly impact the rate of growth of a tumor.

5. (A) Basal cell carcinoma of the skin.

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