C4: Neoplasia/Cancer

• autonomous
• uninterrupted growth
• disorganized

• limited growth (localized)
• homogenous surface
• enclosed in a capsule
• regularly shaped nuclei
• never metastasize

• uncontrollable
• metastasize through blood or lymphatic vessels
• non-homogenous growth
• high N/C ratio (large nucleus)
• hemorrhage

process in which cells move from one part of body to another either via blood of lymphatic vessels

• benign -oma
• malignant -sarcoma

• benign -oma
• malignant -carcinoma

• T= tumor size
• N= lymph node involvement
• M= metastases

• simple metabolism requiring less than normal cells
• requires no support
• cancer cells aggregates on top of each other
• some carry fetal features

• alpha fetoprotein (AFP): a secretory product of liver cancer cells that is not synthesized by normal adult cells
• carcinoembryonic antigen (CEA): a glycoprotein produced by intestinal carcinoma cells that are normally found in embryonic intestinal cells

• carcinogens
• oncogenes: genes that normally encode for cellular proteins but if mutated may cause cancer

• locally (skin or mouth)
• at the site of digestion in the intestines
• at the site of metabolic activation in liver (aflatoxin)
• site of excretion in urine

liver is the primary organ involved in degradation/alteration of carcinogens such as aflatoxin

aromatic amines (procarcinogen)

inactive form of carcinogen

• initiation: induction of irreversible genetic changes to exposed cells
• promotion: initiated cells proliferate stimulated by exposure to carcinogen or other substance
• progression: new genetic features and proliferation of cancer cells without need for carcinogen stimulus
• clonal expansion: rapid proliferation of identical daughter cells

• UV light: creates DNA damage
• Xrays
• radioactive isotopes
• atomic bomb

a genetic disorder where people lack DNA repair enzymes to repair DNA damaged by UV rays. Are more sensitive to sunlight

a natural biologic carcinogen that acts on the liver, derived from fungus

• natural biologic carcinogen 
• parasite that acts on urinary bladder carcinogen

a Chinese liver fluke that acts as a carcinogen for bile duct or liver

• integration of DNA virus (acute transforming RNA virus or oncogenic RNA virus) inserting into genome
• transduction: acute transforming RNA viruses forming cellular oncogenes
• transforms normal cell into malignant cell
• insertion: of slow transforming oncogenic RNA viruses

• lesions in cervix 
• human DNA virus

• herpes
• 90% of US population has antibodies against it, infection may go unnoticed or can produce infections
• leads to Burkitt's Lymphoma and nasopharyngeal carcinoma

• B-cell neoplasia prevalent in sub Saharan African children
• IG gene juxtaposed to myc oncogene from chromosome 8 to chromosome 14

• transmitted by blood
• double stranded DNA virus
• prevalent in Japan, China, Southeast Asia

• related to HIV
• infects human T -lymphocytes in vitro, transforming them into malignant cells

• point mutation
• gene amplification
• chromosomal rearrangement
• insertion of viral genome

• numerous copies of proto oncogene proliferate
• the more oncogene a cell has the more malignant it is

rearrangement of chromosome fragments may stimulate activation of proto-oncogenes

normal cells have tumor suppressor genes that protect cells from oncogenes by suppressing them

• p53: brain tumor
• RB1: retinoblastoma gene
• BRCA 1: breast ovarian carcinomas
• NF1: neurofibrosarcoma

• most common autosomal dominant disease in humans with loss of function of NF1 tumor suppressor gene
• characterized by skin lesions called café au lait spots

large intestines containing polyps that appear in childhood then reach malignancy in adulthood

renal malignant tumor of infancy and childhood

malignant tumors may alter so much that they are perceived as foreign by the body and induce antibody production, which limits the growth of the tumor

tumors that release specific hormones that may resemble certain disorders that can cause misdiagnosis

small cell carcinoma of the lung

squamous cell carcinoma of the lung

renal cell carcinoma

• cusshings syndrome
• hypercalcemia
• polycythemia
• venous thrombosis
• myasthenia gravis

typically common in children where tumors originate from embryonic cells