Data

Copy and paste the text below. It is read-only. Select All

Familial Cancer Early age at onset Two or more relatives are affected Multiple or bilateral tumors Not associated with specific phenotyic marker Example familial colonic cancers Autosomal Recessive Associated with inherited defects of DNA repair ex. Xeroderma pigmentosa anaplasia Lack of cell differentiation (cellular atypia) loss of structural and functional ex. polymorphism, enlarged nucleus, atypical mitosis differentiation The degree to which tissue resemble their origin both in structure and function Cancer cells develop from mutations that occur during the differentiation process. Poorly differentiated tumors tend to be highly malignant Neoplasm Abnormal tissue mass arise from tissue with proliferative capacity Rapid and uncoordinated growth, irreversible Growth persists after cessation of the stimulus Varying degree of differentiation Arise from genetic mutation carcinoma Cancer arises from Epithelial or parenchymal Functional cells of the organ (function) Sarcoma cancer that arises from stromal (Connective tissue, blood vessels, inflammatory cells) Supporting tissue of the organ (structure) Benign Tumors adding "oma" suffix to parenchymal cell type. adenoma, osteoma Well circumscribed localized mass resembles the normal cell of origin morphologically and biochemically. Compress but do not invade the adjacent tissue, does not spread. Often encapsulated by fibrous tissue and can be removed surgically. slow growing fibrous capsule Malignant Tumor are named following the name of the corresponding benign tumor monoclonal origin: transform from a single cell Malignant tumors of the epithelial are Carcinoma Malignant tumors of mesenchymal tissue are Sarcoma no capsule Polyp Any growth, benign or malignant that project out from the surface mucosal epithelium papilloma Benign microscopic finger like projections growing on any surface hamartoma A malformation composed of tissues normally found in the location of origin but in abnormal quantity, mixture or arrangement Ex. stack of chairs in a messy room choristoma A mass of histologically normal tissue present in an abnormal location. Pancreatic tissue in stomach ex. pile of chairs in a swimming pool features of Malignant neoplasm Anaplastic Rapidly growing Invasive (tissues next door) metastasis (far away) pleomorphism variation in shape and size hyperchromatic nuclei giant cells excessive mitotic figures loss of polarity Metastasis secondary growth of tumor in distant areas MOST reliable feature to distinguish malignant from benign dysplasia non neoplastic proliferation epithelial cells pleomorphisms mitotic figures hyperchromiatic nuclei loss of polarity carcinoma in situ localized and confined to the epithelium in which they arise severe dysplasia involves entire thickness of epithelium does not invade basement membrane Rapidly growing cells These cells tend to be poorly differentiated invasion refers to invasion of neighboring structures metastisis is the spread to tissues far away from origin Modes of Metastasis Hematogenous (blood) - sarcoma (liver and lung) Lymphatics - carcinomas seeding - invasion of body cavities (peritoneal cavity, ovarian tumors) sentinel lymph node the first lymph node in a regional lymphatic basin lymphatic spread reactive hyperplasia of lymph node dead cells of tumor invokes reactive changes in node hyperplasia of follicles proliferation of macrophages gross: hard, large, painless Steps in hematogenous spread cells break from primary tumor thru basement mem. invade surrounding ECM gain access to blood vessel survive passage thru blood stream Merge from blood at favorable location (liver, lung) invade surrounding tissue begin to grow E-cadherins hold cells together function is lost in epithelial cancer Steps in Invasion Detachment of tumor cells from each other (E-cadherin) Degradation of ECM Attachment of novel ECM components (new adhesion molecules) Migration of tumor cells (cytoskeleton, cytokines, chemotactic involvment) Tumor heterogeneity variation in metastatic potential cachexia loss of body fat, lean body mass NOT caused by nutritional demand of tumor possibly mediated by TNF paraneoplastic syndrom symptoms which appear in patients with cancer but not explained by the tumor or its metastasis Important b/c: they may be the earliest manifestations may be associated with lethal clinical problems they mimic metastasis Grading of Cancer How aggressive is the tumor a cytological examination Based on: differentiation of tumor cells, number of mitosis Grades I-IV High grade = poorly differentiated low grade = well differentiated *grade of tumor can indicate its response to therapy Staging evaluate the extent and spread of tumor clinical, radiological or surgical examination better than grading in clinically evaluating the tumor Based on: size, extent of spread to LN, presence/absence of metastasis TNM (tumor, node, metastasis) system AJC system - stages 0-IV, size, node, and metastasis Fine needle aspiration aspiration and cytological examination used in palpable lesinons cancers of breast, thyroid, lymph nodes cytology used to diagnose cancer of the cervix, uterus, lung, bladder, prostate, stomach Frozen sections sample is frozen and sectioned and examined immediately uses for examining mass or lymph nodes immunohistochemistry confirms the tissue of origin of metastatic or poorly differentiated tumor uses monoclonal AB specifc for cell markers (serum tumor markers, intermediate filaments) ex. cytokeratin, PSA, estrogen PSA prostate cancer tumor marker CEA gastrointestinal cancer tumor marker A-fetoprotein hepatocellular carcinoma marker Uses of molecular diagnostics of cancer prognosis and behavior detect minimal residues diagnose hereditary predisposition to cancer