CancerCancer BiologyBiology

US StatisticsUS Statistics

• 1 million new 1 million new cases diagnosed cases diagnosed each yeareach year

• #2 cause of death#2 cause of death• Survival rates are Survival rates are

increasing as increasing as detection, detection, diagnosis, and diagnosis, and treatment improvetreatment improve

What is cancer?What is cancer?

• Begins in the cellsBegins in the cells• Process of growth and Process of growth and

division goes wrongdivision goes wrong– New cells form New cells form

incorrectly (mutations)incorrectly (mutations)– New cells form when New cells form when

the body does not need the body does not need them (uncontrolled cell them (uncontrolled cell division)division)

– Old cells do not die Old cells do not die when they shouldwhen they should

Broad Categories of Broad Categories of CancerCancer

• Carcinoma - cancer that begins in the skin or in tissues that Carcinoma - cancer that begins in the skin or in tissues that line or cover internal organs.line or cover internal organs.

• Sarcoma - cancer that begins in bone, cartilage, fat, muscle, Sarcoma - cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue.blood vessels, or other connective or supportive tissue.

• Leukemia - cancer that starts in blood-forming tissue such Leukemia - cancer that starts in blood-forming tissue such as the bone marrow and causes large numbers of abnormal as the bone marrow and causes large numbers of abnormal blood cells to be produced and enter the blood.blood cells to be produced and enter the blood.

• Lymphoma and myeloma - cancers that begin in the cells of Lymphoma and myeloma - cancers that begin in the cells of the immune system.the immune system.

• Central nervous system cancers - cancers that begin in the Central nervous system cancers - cancers that begin in the tissues of the brain and spinal cord. tissues of the brain and spinal cord.

TumorsTumors

• Masses of extra cells or a lump Masses of extra cells or a lump – BenignBenign – cells are still normal, just overgrown; “a – cells are still normal, just overgrown; “a

harmless growth”harmless growth”– MalignantMalignant (cancerous)– cells are abnormal and divide (cancerous)– cells are abnormal and divide

with no controlswith no controls• InvasiveInvasive tumors move from the immediately affected area tumors move from the immediately affected area

and destroy surrounding tissueand destroy surrounding tissue• Can break away and travel throughout the body Can break away and travel throughout the body

((metastasis; metastatic tumors; metastasizedmetastasis; metastatic tumors; metastasized))• AngiogenesisAngiogenesis--

– the growth of new capillary blood vessels in the bodythe growth of new capillary blood vessels in the body– Angiogenesis is a normal and vital process in growth and Angiogenesis is a normal and vital process in growth and

development, as well as in development, as well as in wound healing.wound healing. However, it is However, it is also a fundamental step in the transition of tumors also a fundamental step in the transition of tumors from a dormant state to a malignant one from a dormant state to a malignant one

What causes cancer?What causes cancer?

• Changes Changes (alterations) in (alterations) in genes that control genes that control normal cell growth normal cell growth and divisionand division

• Many reasons why Many reasons why this happensthis happens– EnvironmentalEnvironmental– GeneticsGenetics– Biological Biological

• Ex: VirusesEx: Viruses

SymptomsSymptoms

• A thickening or lump in an areaA thickening or lump in an area• Obvious change in a wart or moleObvious change in a wart or mole• A sore that does not healA sore that does not heal• Nagging cough/hoarsenessNagging cough/hoarseness• Changes in bowel/bladder habitsChanges in bowel/bladder habits• Ingestion/difficulty swallowingIngestion/difficulty swallowing• Unexplained changes in weightUnexplained changes in weight• Unusual bleeding/dischargeUnusual bleeding/discharge**Not all of these symptoms mean a person **Not all of these symptoms mean a person

has cancer, they can have other causeshas cancer, they can have other causes

DiagnosisDiagnosis• BiopsyBiopsy of tumor/affected area- of tumor/affected area-

– A biopsy is the removal of a sample of tissue from A biopsy is the removal of a sample of tissue from the body for examination. The tissue will be the body for examination. The tissue will be examined under a microscope to assist in examined under a microscope to assist in diagnosis.diagnosis.

• PathologistPathologist-Pathologists are doctors who -Pathologists are doctors who study the cause and development of disease; study the cause and development of disease; Pathologists work closely with:Pathologists work closely with:– Histologists-lab professionals who microscopically Histologists-lab professionals who microscopically

study tissue samplesstudy tissue samples– Cytologists-lab professionals who are trained in Cytologists-lab professionals who are trained in

noticing the subtle changes in cells that may noticing the subtle changes in cells that may identify precancerous, malignant or infectious identify precancerous, malignant or infectious conditions. conditions.

• OncologistOncologist-a doctor who specializes in cancer -a doctor who specializes in cancer detection and treatmentdetection and treatment

Treatment Treatment ExamplesExamples• Surgery-remove the mass of Surgery-remove the mass of

cellscells• Chemotherapy-the use of Chemotherapy-the use of

chemicals to destroy/stop the chemicals to destroy/stop the overproduction of cellsoverproduction of cells

• Radiation-use of high energy Radiation-use of high energy waves concentrated in the waves concentrated in the affected areaaffected area

• Hormone therapy-adding, Hormone therapy-adding, blocking or removing hormones blocking or removing hormones that affect cancer growththat affect cancer growth

• Biological therapy-using the Biological therapy-using the body’s own immune system to body’s own immune system to fight cancerous cellsfight cancerous cells

• Homeopathic/alternative Homeopathic/alternative medicine-using diet, herbs and medicine-using diet, herbs and other natural methodsother natural methods

PreventionPrevention

• Living a healthy Living a healthy lifestylelifestyle– No smoking, eating No smoking, eating

right, exercise, right, exercise, avoiding excessive avoiding excessive sunlightsunlight

– Awareness of Awareness of disease/family disease/family historyhistory

– Regular check-upsRegular check-ups– ScreeningsScreenings

Think About These Think About These Questions…Questions…

• What are the odds that you one day What are the odds that you one day will get cancer?will get cancer?

• Are you doing anything to prevent Are you doing anything to prevent yourself from getting cancer?yourself from getting cancer?

• How has cancer has affected your How has cancer has affected your life?life?

• What are your thoughts on curing What are your thoughts on curing cancer?cancer?