06 - Neoplasia Flashcards
An abnormal mass of tissue the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after the cessation of stimuli, which evoked the change.
Neoplasm
Localized neoplasms; usually ends with _oma, except lymphoma, seminoma, dysgerminoma, and hepatoma, and melanoma (these are malignant neoplasms).
Benign neoplasms
Neoplasms that invade and destroy adjacent tissues.
Malignant neoplasms
Malignant neoplasms of epithelial origin; usually spread by lymphatic route; example: colorectal adenocarcinoma.
Carcinomas
Malignant neoplasms of mesenchymal origin; usually spread by hematogenous route; example: uterine leiomyosarcoma.
Sarcomas
Benign, but disorganized appearance of tissue indigenous to a particular organ; example: Peutz-Jegher polyp
Hamartoma
Cytologically and architecturally normal tissue in an ectopic location; example: Ectopic gastric tissue in Meckel diverticulum
Choristoma
Extent to which neoplastic cells resemble their normal forebears morphologically and functionally.
Differentiation
Considered a hallmark of malignancy, which literally means to form backward; term used to describe cells with little or no differentiation.
Anaplasia
Disorderly but non-neoplastic proliferation of cells; described as a loss in uniformity of individual cells and in their architectural orientation.
Dysplasia
Fibrous tissue formation in response to neoplasm.
Desmoplasia
Dysplastic changes, which involve the entire thickness of the epithelium.
Carcinoma in situ
Development of secondary implants discontinuous with the primary tumor, in remote tissues; more than any other attribute, this identifies a neoplasm as malignant.
Metastasis
Next to metastasis, this is the most reliable feature that distinguishes malignant from benign tumors.
Local invasiveness
Top 3 common cancers in children.
ALL > CNS tumors > Burkitt lymphoma
Top 3 common cancers in males.
Prostate > Lung > Colorectal
Top 3 common cancers in females.
Breast > Lung > Colorectal
Top 3 common cancer mortalities in males.
Lung > Prostate > Colorectal
Top 3 common cancer mortalities in females.
Lung > Breast > Colorectal
Hallmarks of cancer.
Self-sufficiency in growth signals; insensitivity to growth inhibitory signals; evasion of cell death; limitless replicative potential; development of sustained angiogenesis; and ability to invade and metastasize
Normal cellular genes whose products promote cell proliferation; examples: RAS (most commonly mutated proto-oncogene in human cancers), and ABL (in CML)
Proto-oncogenes
Mutant or overexpressed versions of proto-oncogenes that function autonomously without a requirement for normal growth-promoting signals.
Oncogenes
Genes whose products apply brakes to the cell proliferation; loss of function mutations of such genes lead to carcinogenesis.
Tumor suppressor genes
Governor of the cell cycle; a tumor suppressor gene that antiproliferative effects by controlling G1-S checkpoint in the cell cycle; mutated in Retinoblastoma; key element in HPV tumorigenesis.
Rb
Guardian of the genome; a tumor suppressor gene that regulates cell cycle progression, DNA repair, cellular senescence, and apoptosis, and the most frequently mutated tumor-suppressor gene in human cancers; mutated in Li-Fraumeni syndrome.
p53
Metabolism unique to cancer cells; High glucose uptake and increased conversion of glucose to lactose (fermentation), which provides carbon moieties necessary for biosynthesis and growth of cancer cells.
Warburg metabolism
Most common mechanism of evasion of apoptosis used by cancer cells.
Interference in the intrinsic (mitochondrial) pathway of apoptosis
The limitless replicative potential of cancer cells are due to the following mechanisms:
Inactivation of senescence signals and reactivation of telomerase
Mechanisms of angiogenesis in cancer cells.
VEGF and oncogenes that stimulate synthesis of VEGF (RAS, MYC and MAPK)
Steps in invasion and metastases of cancer cells.
A. Loosening of cell-cell contacts
B. Degradation of ECM components
C. Attachment of novel ECM components
D. Migration of tumor cells
Term used to describe the degree of differentiation based on histologic appearance of the tumor.
Tumor grade
Term used to describe the degree of localization/spread of the tumor; usual criteria: location and size of the primary tumor, nodal status, and presence of distant metastases; has more prognostic value than tumor grade.
Tumor stage
Progressive loss of body fat and lean body mass, accompanied by profound weakness, anorexia, and anemia in cancer patients; main cytokine implicated is TNF.
Cancer cachexia
Symptom complexes that occur in patients with cancer that cannot be readily explained by local and distant spread of the tumor of by elaboration of hormones not indigenous to the tissue of origin of the tumor; examples: ectopic ACTH production (Cushing syndrome) in Small cell lung cancer; Hypercalcemia in squamous cell carcinoma (due to PTHrp expression)
Paraneoplastic syndromes
Condition secondary to release of products of dying cancer cells during chemotherapy; characterized by: hyperkalemia, hyperphosphatemia, hyperuricemia, and hypocalcemia.
Tumor lysis syndrome
