Oncology

cancer

uncontrolled cell proliferation and spread of abnormal cells

women

breast, lung, and colon/rectum

men

prostate, lung, colon/rectum

declining rates of cancer

due to prevention and detection, surveillance, intervention, and coordination between specialists

Risk factors

heredity, aging, lifestyle, geographic/environmental variables, precancerous lesions, stress

heredity

only 5-10% of cancers are linked to this

preventable

most cancers are_____

66 years old

the median age of primary diagnosis

cigarette smoking

linked to 90% of lung cancers

dietary causes

1/3 of cancer mortality linked to this

progression

there is a link between behavioral and psychologic factors and the _____ of cancer

differentiation

process by which normal cells undergo physical and structural changes as they develop to form tissues

mutation

differentiation is altered and malignant

hyperplasia

increased number of cells in tissue and increased tissue mass

can be normal in physiological function such as, wound healing, callus forming

neoplastic hyperplasia

increase in cell mass due to tumor or formation

dysplasia

disorganization of cells in which an adult cell varies from its normal size, shape, or organization

may revere itself or lead to cancer

often caused by chronic irritation

metaplasia

early dysplasia

reversible and benign but still an abnormal change

tumors

“neoplasms”

abnormal new growth of tissues that serves no functional purpose and may harm the host organism

competes for blood supply/nutrients and doesn’t respond to normal body function

primary tumors

normally local to the given structure

secondary tumors

cells have metastasized from another part of the body

classifications of neoplasms

cell type, tissue of origin, degree of differentiation, anatomic site, benign/malignant

stage 0

carcinoma in situ

stage I

early stage, cancer localized to primary organ

stage II

increased risk of regional spread because of tumor size/grade

stage III

local cancer has spread regionally but may not be disseminated to distant regions

stage IV

cancer has spread and disseminated to distant sites

somatic mutuation theory

neoplasia originates in a single cell

numerical chnages

the addition or deletion of entire chromosomes

structural changes

translocations, deletions, inversions, and insertions of parts of chromosomes

oncongenes

cancer causing genes

transform normal cells into malignant cells, independently or incorporated with a virus

tumor suppressor genes

the “brakes” to the “stuck accelerator” of the activated oncogene

can regulate growth and inhibit carcinogenesis

aggressive cell proliferation

takes place when defects in the oncogene occur simultaneously with the inactivation of growth-suppressing genes

carcinogenesis

process by which a normal cell undergoes malignant transformation

NK cells

directly kill cancer cells without any previous exposure to the tumor

macrophages

can function as effectors that kill tumor cels

complement dependent cytotoxicity

can be mediated by antibodies

cytotoxic CD8+ cells

the major immunologic barrier against tumora

loss of immunogenecity

tumors can mutate antigenic peptides so that they cannot be loaded onto the class I MHC and be presented to CD8+ cells

cytotoxic T cell cannot make good contact with the tumor cell and undergo the remaining steps of triggering its killing mechanism

antigenic modulation

refers to loss of surface antigen

tumor antigens are internalized or down regulated so that antibodies cannot bind

induction of immune supression

tumors produce a variety of suppressive factors that inhibit NK and T cells directly

eradicating metastases

key factor to cure cancer

newly formed blood vessels

easily invaded by the cancer cells that are closely adjacent to them

angiogenesis

blood vessels from preexisting vessels grow into the tumor

disease free survival

describes the time between diagnosis and recurrence or relapse

stage at time of initial therapy

most important predictors of recurrent cancer

incisional or open biopsy

consists of making an incision and removing a portion of the abnormal tissue

does not attempt to remove the entire pathologic structure

excisional biopsy

aka lumpectomy

consists of making an incision to excise all gross, abnormal tissue that is either visually apparent or identified

clear margins

surgeon will try to obtain these with a resection

tumor biomarkers

substances produced and secreted by tumor cells may be found in the blood

test panels

used more frequently than just individual tumor marker evaluations

specific cancer biomarkers

can help determine the aggressiveness of the tumor, potential response to treatment, and prediction of risk for cancer diagnosis within a family

immunohistochemistry

identifies the presence of specific proteins at the cellular level

signal status of genes

illustrated by gene expression by microarray

fluorescence in situ hybridization

identify genes with multiple copies or arrangements

DNA sequencing via polymerase chain reaction

can identify mutations in selected genes

surgery

most often in combination with other therapies

micro metastases

require additional treatment (chemo radiation)

irradiation therapy

delivered over weeks to capture cells at each stage of proliferation

two goals of irradiation therapy

1.destroy the dividing cancer cells by destroying hydrogen bonds between DNA strands within the cancer cells

2.limit damage to resting normal cells

irradiation therapy with surgery

•May be used preoperatively to shrink a tumor, making it operable, while preventing further spread of the disease during surgery.

•After the surgical wound heals, postoperative doses prevent residual cancer cells from multiplying or metastasizing.

specific chemotherapy agents

kill cancer cells by affecting DNA synthesis/function

resistant cells

may develop after treatment

improved survival rates

occur with screening and early detection/treatment

poor prognosis

for anyone with advanced, disseminated cancer

rates of change

in terminally ill pts, these are more important indicators of survival than absolute measures