Flashcards in PATH: Neoplasia I/II Deck (31):
What is the difference between neoplasm, tumor, and cancer?
A neoplasm is new cellular growth that is abnormal, uncontrolled, excessive, or purposeless, and a tumor is a mass or swelling that can be used to describe any neoplasm. Cancer is the common term for all malignant neoplasms.
What is a malignant neoplasm?
A growth that is invasive, destroys surrounding tissue, grows relentlessly, and can metastasize
What is metastasis?
The spread of a tumor from its site of origin to a distant site
True or False: All cancers that metastasize are malignant, but not all malignant tumors have to metastasize.
True or False: A benign tumor can metastasize so long as it does not cause tissue injury
False- benign tumors do not metastasize
What is anaplasia?
The lack of differentiation/specialization
What is the histological appearance of anaplastic cells?
They exhibit cytological and nuclear pleomorphism (variation in size, shape, staining intensity); hyperchromasia (dark staining nucleus due to increased DNA); large nucleoli and abnormal nuclei; variation in nucleoli #; high mitotic rate; high nuclear to cytoplasm ratio
What is encapsulation and what type of tumor is it characteristic of?
A peripheral , circumferential fibrous connective tissue rim around benign tumors
What is invasion?
Infiltration into adjacent structures, as seen with malignant tumors
What is parenchyma? The stroma?
The tissue characteristic of an organ or neoplasm-- the functional cells of an organ-- as opposed to the connective or supporting tissues (the stroma)
What is desmoplasia? What is a desmoplastic tumor?
Desmoplasia is the exuberant production of collegenous stroma induced by tumor cells; A tumor with dense collagenous stroma (fibrosis) induced by the tumor cells which form a firm, hard mass
What is a medullary tumor?
A tumor without significant collagenous stroma
What is dysplasia?
Variation in the size and shape of cells (pleomorphism) with loss of normal orientation but normal mitoses are present
What is the only characteristic that can be used to determine malignancy on its own?
What is cachexia?
General wasting related to advanced malignancies; drastic loss of body mass, especially lean muscle mass
What are the gross features of malignancy?
Large size, invasion/ lack of encapsulation, necrosis, friability (brittle), multiple lesions, lymph node involvement, metastasis
What are the microscopic features of malignancy?
Anaplasia/pleomorphism, cellular crowding/ nuclear overlap, increased mitotic rate, bizarre mitotic figures
True or False: Tumor cells always proliferate at a faster rate than normal cells
What is the proliferative index and what are the different categories?
A measure of what % of cells are in the S phase of the cell cycle; 0-12% is a low/favorable prognosis or a slowly proliferating tumor, 13-35% is intermediate/borderline prognosis; >36%= rapidly proliferating tumor
If cancerous cells are immortal then why is necrosis characteristic of malignant tumors?
Because the cells are rapidly dividing they can outgrow their blood supply
What is the difference between monoclonal and polyclonal tumors?
Monoclonal tumors arise from one single cell that has undergone a neoplastic transformation; Polyclonal tumors arise from more than one cell
Are most tumors monoclonal or polyclonal?
Most tumors start out monoclonally but pick up mutations along the growing process and thusly become polyclonal
What are the two major biologic hallmarks of cancer?
Invasion and metastasis
What are the major routes of metastatic spread of cancer? What types of cancer are characteristic of each spreading route?
Lymphatic spread- dominant route in most carcinomas; Hematogenous spread- dominant route for sarcomas; or direct extension/ seeding- colonic/ovarian carcinoma
What are two most common sites of metastasis?
Liver and lungs
What types of cancers are most likely to invade the bone?
Prostate, lung, breast, kidney
What types of cancers are most likely to invade the brain?
Lung, breast, and kidney
What is carcinoma in situ?
A marked dysplastic change involving the entire thickness of the epithelium but confined by the basement membrane ; it is a preinvasive neoplasm
What is the basic general mechanism by which tumor cells invade and metastasize?
1) tumor cells acquire receptors that bind to laminin and fibronectin of extracellular matrix, 2) proteolytic enzymes secreted by the tumor cells lyse the matrix components 3) tumor cells migrate to the degraded zone of the extracellular matrix
What is a sentinel node?
The first lymph node into which a primary tumor will drain