Pathologic basis of disease (9th) - test bank - chapter 7

Kumar: Robbins and Cotran Pathologic Basis of Disease, 9th Edition Chapter 07: Neoplasia Test Bank MULTIPLE CHOICE 1. Which of the following tumors occurs most often in the ovary? a. Chondroma b. Hemangioma c. Leiomyoma d. Transitional cell papilloma e. Cystadenoma ANS: E, Cystadenomas, which may contain serous fluid or mucin and are thus called serous or mucinous cystadenomas, are typically found in the ovary. These benign tumors have malignant counterparts known as cystadenocarcinomas. 2. Which one of the following carcinomas is locally invasive but rarely forms metastases in lymph nodes and distant sites? a. Basal cell carcinoma of the skin b. Squamous cell carcinoma of the skin c. Oat cell carcinoma of the lung d. Transitional cell carcinoma of the urinary bladder e. Adenocarcinoma of the stomach ANS: A, Basal cell carcinomas of the skin, the most common malignant tumor in the human body, is a locally invasive malignant tumor, which, if untreated, could ultimately kill the host. However, these tumors are usually diagnosed early and removed adequately, so that they almost never metastasize. 3. Pseudomyxoma peritonei is a complication of which tumor? a. Serous cystadenoma of the ovary b. Mucinous cystadenoma of the ovary c. Ovarian fibroma d. Myxoma of the heart e. Myxosarcoma of the lower extremity ANS: B, Pseudomyxoma of the ovary usually results from peritoneal seeding of mucin-secreting tumors of the ovary or the gastrointestinal tract, and most often the appendix. Although the ovarian tumor is benign, the implants of the tumor cells seeding the peritoneal cavity can be difficult to eradicate. The cells continue to secrete mucin and fill the abdominal cavity, colloquially known as "jelly-belly." 4. Which mechanism affecting the genes or chromosomes accounts for the activation of the c-myc protooncogene in Burkitt lymphoma cells? a. Overexpression b. Amplification c. Point mutation d. Translocation e. Inactivation of its promotor ANS: D, Translocation of the c-myc protooncogene from its normal site on chromosome 8 to chromosome 14 results in the formation of the myc oncogene and plays a major role in the pathogenesis of Burkitt lymphoma. 5. Homogeneous staining regions (HSR) of chromosome 2p, the site of the N-myc gene, are adverse prognostic signs if found in neuroblastoma cells. HRS are evidence of gene a. deletion b. amplification c. point mutation d. translocation e. inversion ANS: B, Homogeneous staining regions and double minutes are signs of gene amplification. Amplification of the N-myc oncogene in neuroblastoma cells is a poor prognostic finding. 6. In which cell function is BRCA1, a gene mutated in women with familial breast carcinoma, involved? a. Cell adhesion b. Growth inhibition c. Signal transduction d. Cell surface channel e. Transcriptional regulation and DNA repair ANS: E, BRCA1 and BRCA2 are tumor suppressor genes whose true function has not been fully elucidated. It is thought that they participate in the transcriptional regulation and interact with proteins that regulate double-strand DNA repair. 7. Germ line mutation of E-cadherin is found in familial cases of a. lymphoblastic lymphoma b. Ewing sarcoma c. neuroblastoma d. gastric carcinoma e. seminoma ANS: D, E-cadherin is a cell-to-cell adhesion molecule that serves to hold many epithelial cells together. This surface adhesion molecule is often lost in adenocarcinomas, accounting for the invasive growth of these neoplasms. Germ line mutation of the E-cadherin gene has been found in families with gastric carcinoma. 8. Germ line mutation of the Von Hippel–Lindau (VHL) gene is associated with formation of retinal angiomas and a. glioblastoma multiforme b. oligodendroglioma c. neurinomas d. ependymomas e. cerebellar hemangioblastomas ANS: E, Von Hippel–Lindau syndrome was originally described as a syndrome comprising angiomas of the retina and hemangioblastomas of the cerebellum. It is linked to the germ line mutation of the VHL tumor suppressor gene. These patients are at risk of developing renal cell carcinoma and pheochromocytomas. Mutations of the VHL gene also have been found in sporadic renal carcinomas unrelated to Von Hippel–Lindau syndrome. 9. Microsatellite instability, a marker of DNA mismatch repair, is typically found in a. hereditary nonpolyposis colon cancer b. familial adenomatous polyposis coli c. T-cell lymphoma d. B-cell lymphoma e. myelogenous leukemia ANS: A, Mutations of human DNA mismatch repair genes play a pathogenetic role in the development of colonic cancers in families with hereditary nonpolyposis colon cancer (HNPCC). Due to the error in mismatch repair, the microsatellite sequences (normally fixed for life and the same in every tissue) expand. They account for the microsatellite instability, a hallmark of all conditions with defective DNA mismatch repair. 10. Matrix metalloproteinases secreted by tumor cells are important for which feature of malignant tumors? a. Desmoplasia b. Anaplasia c. Invasiveness d. Apoptosis e. Differentiation ANS: C, Matrix metalloproteinases, such as type IV collagenase, are important for the invasive growth of tumor cells. These enzymes degrade the basement membranes and the extracellular matrix, allowing the tumor cells to penetrate into the tissues, lymphatics, and blood vessels. 11. Which enzymes in the liver account for the activation of most procarcinogens into carcinogens? a. Cytochrome P-450-dependent mono-oxidases b. Aminotransferases c. Hydroxylases d. Glutathione dehydrogenase e. Caspases ANS: A, Most of the exogenous procarcinogens are activated into carcinogens in the liver through the action of microsomal cytochrome P-450–dependent mono-oxidases found in the smooth endoplasmic reticulum of hepatocytes. Susceptibility to carcinogens is in part determined by the polymorphism of genes that encode these enzymes. 12. Which is the most common radiation-induced cancer in humans? a. Thyroid cancer b. Chronic lymphocytic leukemia c. Breast cancer d. Lung cancer e. Salivary gland carcinoma ANS: B, Leukemias represent the most common radiation-induced cancer in humans, closely followed by thyroid cancer, which is the most common malignancy in young persons. 13. Helicobacter pylori infection predisposes to formation of gastric tumors, but the association between the bacterial infection and a gastric tumor is the strongest for a. adenocarcinoma of the stomach b. gastrointestinal stromal tumors c. marginal zone lymphomas d. T-cell lymphoma e. Burkitt lymphoma ANS: C, The best and strongest evidence links Helicobacter pylori infection with the onset of mucosa-associated B-cell lymphomas (MALTomas) of the stomach, which are also known as marginal zone lymphomas. It is thought that H. pylori activates T cells, which in turn promote polyclonal proliferation of B cells in the gastric mucosa. In this process, some cells obviously become malignant and give rise to T-cell independent low-grade monoclonal lymphomas. 14. Clubbing of the digits, periosteal new bone formation on the metatarsals, metacarpals, and proximal phalanges, and arthritis of adjacent joints is a paraneoplastic syndrome most often associated with carcinoma of the a. thyroid b. larynx c. bronchi d. liver e. stomach ANS: C, Clubbing of the fingers and related bone and joint changes of the hand and fingers are signs of hypertrophic osteoarthropathy, which most often occurs in patients with bronchogenic carcinoma. The pathogenesis of these changes is not known.