cancer . learning objectives understand the relationship between cancer and cellular genetic...

CANCERCANCER

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Learning ObjectivesLearning Objectives

Understand the relationship between cancer Understand the relationship between cancer and cellular genetic controls.and cellular genetic controls.

Know the steps in cancer development.Know the steps in cancer development. List the environmental factors that influence List the environmental factors that influence

cancer development.cancer development. Describe the relationship between lifestyle Describe the relationship between lifestyle

and cancer.and cancer. Describe some of the characteristics of Describe some of the characteristics of

more well-known cancers. more well-known cancers.

Impacts/IssuesImpacts/Issues

Between You Between You and Eternityand Eternity

Between You and Eternity Between You and Eternity

Cancer affects one in three people in the Cancer affects one in three people in the U.S. and kills one in four; each year more U.S. and kills one in four; each year more than 200,000 women are diagnosed with than 200,000 women are diagnosed with breast cancer alone.breast cancer alone.

Some women carry the BRCA1 or BRCA2 Some women carry the BRCA1 or BRCA2 gene, which increases the risk of developing gene, which increases the risk of developing breast cancer.breast cancer.

Some women with elevated risk for breast Some women with elevated risk for breast cancer opt for preventive mastectomy.cancer opt for preventive mastectomy.

Diagnosed early, most cancers are Diagnosed early, most cancers are treatable, and many curable.treatable, and many curable.

Video: Preventing Cancer SurgicallyVideo: Preventing Cancer Surgically

This video clip is available in CNN Today This video clip is available in CNN Today Videos for Anatomy and Physiology, 2003, Videos for Anatomy and Physiology, 2003, Volume VII. Instructors, contact your local Volume VII. Instructors, contact your local sales representative to order this volume, sales representative to order this volume, while supplies last.while supplies last.

Useful References for Impacts/IssuesUseful References for Impacts/Issues

The latest references for topics covered in this section can be found at The latest references for topics covered in this section can be found at the book companion website. Log in to the book’s e-resources page at the book companion website. Log in to the book’s e-resources page at www.thomsonedu.com to access InfoTrac articles. www.thomsonedu.com to access InfoTrac articles.

Genome News Network: Breast Cancer Genome News Network: Breast Cancer Susceptibility Genes: Overstating the Risk?Susceptibility Genes: Overstating the Risk?

InfoTrac: Monster Tumors Show Scientific InfoTrac: Monster Tumors Show Scientific Potential in War against Cancer. Elizabeth Potential in War against Cancer. Elizabeth Svoboda. Svoboda. The New York TimesThe New York Times, June 6, , June 6, 2006.2006.

How Would You Vote?How Would You Vote?To conduct an instant in-class survey using a classroom response To conduct an instant in-class survey using a classroom response system, access “JoinIn Clicker Content” from the PowerLecture main system, access “JoinIn Clicker Content” from the PowerLecture main menu. menu.

Would you support legislation requiring Would you support legislation requiring insurers to pay for the removal of a breast insurers to pay for the removal of a breast that is only at risk for developing cancer? that is only at risk for developing cancer? a. Yes, they should be required to pay at least in a. Yes, they should be required to pay at least in

proportion to a woman's chances for developing proportion to a woman's chances for developing cancer.cancer.

b. No, they should pay for annual exams, but not b. No, they should pay for annual exams, but not for surgery unless cancer is actually detected. for surgery unless cancer is actually detected.

Useful References for Useful References for How Would You Vote?How Would You Vote?


InfoTrac: Breast Removal: The Latest in Cancer InfoTrac: Breast Removal: The Latest in Cancer Prevention. Prevention. HealthFactsHealthFacts, Feb. 1999., Feb. 1999.

InfoTrac: Is a 0.2% Chance of Death from Breast InfoTrac: Is a 0.2% Chance of Death from Breast Cancer Worth a Bilateral Prophylactic Mastectomy? Cancer Worth a Bilateral Prophylactic Mastectomy? Contemporary OB/GYNContemporary OB/GYN, June 2005., June 2005.

American Cancer Society: Insurance May Not American Cancer Society: Insurance May Not Cover Preventive Surgery for High-Risk WomenCover Preventive Surgery for High-Risk Women

Section 1Section 1

Cancer: Cell Cancer: Cell

Controls Go AwryControls Go Awry

Cancer: Cell Controls Go Awry Cancer: Cell Controls Go Awry

Some tumors are cancer, others are not.Some tumors are cancer, others are not. Overgrowth of cells in a tissue (Overgrowth of cells in a tissue (hyperplasiahyperplasia) )

results in the formation of a defined mass called results in the formation of a defined mass called a a tumortumor, or , or neoplasmneoplasm..

Figure 23.2Figure 23.2


Benign tumorsBenign tumors are often enclosed in a capsule are often enclosed in a capsule of connective tissue.of connective tissue.

• The cells are organized in orderly array.The cells are organized in orderly array.• The cells grow slowly and are well differentiated.The cells grow slowly and are well differentiated.• Because they do not affect surrounding tissue (there Because they do not affect surrounding tissue (there

are exceptions), they usually are not considered a are exceptions), they usually are not considered a threat to health.threat to health.

© 2007 Thomson Higher Education Fig 23.1, p.428

capsule


DysplasiaDysplasia is an abnormal change in the sizes, is an abnormal change in the sizes, shapes, and organization of cells in a tissue.shapes, and organization of cells in a tissue.

• It is often a precursor to It is often a precursor to cancercancer..• Microscopically, the edges of the tumor look ragged Microscopically, the edges of the tumor look ragged

and the cells are clumped.and the cells are clumped.• Functionally the cells have many characteristics that Functionally the cells have many characteristics that

alter their behavior from that of normal cells.alter their behavior from that of normal cells.


Cancer cells have abnormal structure.Cancer cells have abnormal structure. A cancer cell has a large nucleus, less A cancer cell has a large nucleus, less

cytoplasm, and is poorly differentiated.cytoplasm, and is poorly differentiated. The cytoskeleton shrinks and becomes The cytoskeleton shrinks and becomes

disorganized; proteins of the plasma membrane disorganized; proteins of the plasma membrane also become altered.also become altered.

Cellular division of transformed cells results in Cellular division of transformed cells results in cancerous daughter cells.cancerous daughter cells.


Cancer cells lack normal controls over cell Cancer cells lack normal controls over cell division.division.

In a cancerous tumor, more cells are dividing In a cancerous tumor, more cells are dividing than dying, so growth continues unaffected by than dying, so growth continues unaffected by the usual contact inhibition provided by the usual contact inhibition provided by crowding.crowding.

Cancer cells lack strong cell-to-cell junctions Cancer cells lack strong cell-to-cell junctions and so tend to move about (and so tend to move about (metastasismetastasis) and ) and become become malignantmalignant..

Cancer cells break away from their home tissue.

The metastasizing cells become attached to the wall of a blood vessel or lymph vessel. They secrete digestive enzymes into it. Then they cross the wall at the breach.

Cancer cells creep or tumble along inside blood vessels, then leave the bloodstream the same way they got in. They start new tumors in new tissues.

Fig 23.3, p.429

a

b

c


Some cancer cells produce HCG (human Some cancer cells produce HCG (human chorionic gonadotropin), which can be detected chorionic gonadotropin), which can be detected in blood and which signals cancer somewhere in blood and which signals cancer somewhere in the body; cancer cells also produce in the body; cancer cells also produce angiogeninangiogenin, which encourages new blood , which encourages new blood vessel development.vessel development.

Video: Fibroid TumorsVideo: Fibroid Tumors

This video clip is available in CNN Today This video clip is available in CNN Today Videos for Anatomy and Physiology, 2004, Videos for Anatomy and Physiology, 2004, Volume VIII. Instructors, contact your local Volume VIII. Instructors, contact your local sales representative to order this volume, sales representative to order this volume, while supplies last.while supplies last.

Useful References for Section 1Useful References for Section 1


InfoTrac: Gene Signature Helps Predict InfoTrac: Gene Signature Helps Predict Melanoma Outcome. Diana MahoneyMelanoma Outcome. Diana Mahoney. . Internal Medicine NewsInternal Medicine News, Mar. 1, 2006., Mar. 1, 2006.

Section 2Section 2

The Genetic Triggers The Genetic Triggers for Cancerfor Cancer

The Genetic Triggers for Cancer The Genetic Triggers for Cancer

Cancer develops in a multistep process.Cancer develops in a multistep process. The transformation of a normal cell into a The transformation of a normal cell into a

cancerous one is called cancerous one is called carcinogenesiscarcinogenesis.. Cancer develops through a series of changes Cancer develops through a series of changes

that upset normal controls over cell division.that upset normal controls over cell division. Oncogenes induce cancer when tumor Oncogenes induce cancer when tumor

suppressor genes are mutated.suppressor genes are mutated. Proto-oncogenesProto-oncogenes are normal genes that are normal genes that

regulate cell growth and development.regulate cell growth and development.

© 2007 Thomson Higher Education

POSSIBLE TRIGGERS virus

heredity

chemical carcinogens

radiation

normal cell

mutation in proto-oncogenes and tumor suppressor genes remove normal growth controls

abnormal cell

immune system breakdown

abnormal cell proliferates

immune system activated(cytotoxic T cells and NK cells)

abnormal cell destroyed

tumor

tumor cells break away; metastasis to other parts of body

Fig 23.4, p.430

POSSIBLE TRIGGERS

normal cell

abnormal cell

abnormal cell destroyed

tumor

tumor cells break away; metastasis to other parts of body

Fig 23.4, p.430

Stepped Art

abnormal cell proliferates

immune system breakdown immune system activated(cytotoxic T cells and NK cells)

virus

heredity

chemical carcinogens

radiation

mutation in proto-oncogenes and tumor suppressor genes remove normal growth controls


OncogenesOncogenes are modified from proto- are modified from proto-oncogenes; they code for altered proteins that oncogenes; they code for altered proteins that remove the controls over cellular division.remove the controls over cellular division.

• Cancer cannot be caused by oncogenes alone but Cancer cannot be caused by oncogenes alone but requires the absence or mutation of requires the absence or mutation of tumor tumor suppressor genessuppressor genes..

• For example, For example, retinoblastomaretinoblastoma is normally is normally suppressed by at least one gene, but if this gene is suppressed by at least one gene, but if this gene is altered, the suppression is removed and cancer altered, the suppression is removed and cancer develops.develops.

• BRCA1 and BRCA2 are also tumor suppressor BRCA1 and BRCA2 are also tumor suppressor genes whose disruption can lead to breast cancer.genes whose disruption can lead to breast cancer.

Fig 23.5, p.431Chromosome 13

BRCA 1

BRCA 2

Chromosome 17


The The p53 genep53 gene codes for a regulatory protein codes for a regulatory protein that turns on proto-oncogenes that stop cell that turns on proto-oncogenes that stop cell division at the right time; its alteration removes division at the right time; its alteration removes this inhibition and allows cells to divide this inhibition and allows cells to divide unchecked.unchecked.

An oncogene may mutate in a way that triggers An oncogene may mutate in a way that triggers expression.expression.

• Translocation may move an oncogene away from a Translocation may move an oncogene away from a regulatory nucleotide sequence that normally regulatory nucleotide sequence that normally prevents its expression.prevents its expression.

• New genetic material may be introduced into a cell New genetic material may be introduced into a cell (as by a virus) and disrupt controls.(as by a virus) and disrupt controls.


There also are other routes to cancer.There also are other routes to cancer. Inherited susceptibility to cancer.Inherited susceptibility to cancer.

• If a mutation occurs in a germ cell and it removes If a mutation occurs in a germ cell and it removes controls over a proto-oncogene, the defect can be controls over a proto-oncogene, the defect can be passed on to offspring.passed on to offspring.

• Most instances of inherited cancer susceptibility are Most instances of inherited cancer susceptibility are complicated by the fact that several genes are complicated by the fact that several genes are probably involved.probably involved.

Viruses.Viruses.• Viruses can become inserted into host cell DNA, Viruses can become inserted into host cell DNA,

possibly altering the functioning of proto-oncogenes.possibly altering the functioning of proto-oncogenes.• Viruses can also carry oncogenes and insert them Viruses can also carry oncogenes and insert them

into host cell DNA.into host cell DNA.


Chemical carcinogens.Chemical carcinogens.• CarcinogensCarcinogens are chemicals that can damage DNA, are chemicals that can damage DNA,

resulting in subsequent mutations.resulting in subsequent mutations.• Some of the chemicals that cause cancer are by-Some of the chemicals that cause cancer are by-

products of an industrialized society, such as products of an industrialized society, such as asbestos, vinyl chloride, and benzene; hydrocarbons asbestos, vinyl chloride, and benzene; hydrocarbons in cigarette smoke and fireplace soot; and in cigarette smoke and fireplace soot; and substances in dyes and pesticides.substances in dyes and pesticides.

• Natural carcinogens include Natural carcinogens include aflatoxinaflatoxin,, produced by produced by a fungus that grows on peanuts.a fungus that grows on peanuts.

• Some chemicals may be “pre-carcinogens” that Some chemicals may be “pre-carcinogens” that cause changes only after they have been altered by cause changes only after they have been altered by metabolic activity of the cell.metabolic activity of the cell.


Radiation.Radiation.• Radiation can damage DNA.Radiation can damage DNA.• Sources include UV radiation from sunlight and Sources include UV radiation from sunlight and

tanning lamps, X rays, cosmic rays, radon gas, and tanning lamps, X rays, cosmic rays, radon gas, and nuclear reactors; sun exposure is probably the nuclear reactors; sun exposure is probably the greatest risk factor.greatest risk factor.

Breakdowns in immunity.Breakdowns in immunity.• A healthy immune system regularly detects and A healthy immune system regularly detects and

destroys cancer cells by means of cytotoxic T cells.destroys cancer cells by means of cytotoxic T cells.• The protective function of the immune system can be The protective function of the immune system can be

compromised by therapeutic drugs or even anxiety compromised by therapeutic drugs or even anxiety and severe depression.and severe depression.

• Sometimes, the cancer itself can suppress the Sometimes, the cancer itself can suppress the immune system.immune system.



Cancer Backup: Retinoblastoma in ChildrenCancer Backup: Retinoblastoma in Children InfoTrac: Study IDs Gene Triggers to Liver InfoTrac: Study IDs Gene Triggers to Liver

Cancer. Jamie Talan. Cancer. Jamie Talan. Newsday (Melville, Newsday (Melville, NY)NY), June 28, 2006., June 28, 2006.

InfoTrac: Scientists Link Gene to Metastatic InfoTrac: Scientists Link Gene to Metastatic Cancer. Cancer. UPI NewsTrackUPI NewsTrack, July 3, 2006., July 3, 2006.

Section 3Section 3

Assessing the Cancer Risk Assessing the Cancer Risk from Environmental from Environmental

ChemicalsChemicals

Assessing the Cancer Risk from Assessing the Cancer Risk from Environmental Chemicals Environmental Chemicals

According to the American Cancer Society, According to the American Cancer Society, factors in the environment account for half factors in the environment account for half of all cancers; these factors include UV of all cancers; these factors include UV light, radiation, and industrial and light, radiation, and industrial and agricultural chemicals.agricultural chemicals.

Roughly 40% of the food Roughly 40% of the food in supermarkets in the in supermarkets in the U.S. contains pesticide U.S. contains pesticide residues; some of these residues; some of these pesticides are banned in pesticides are banned in the U.S., but come in on imports.the U.S., but come in on imports.


Assessing the Cancer Risk from Assessing the Cancer Risk from Environmental Chemicals Environmental Chemicals

More exposure comes from pesticides used in More exposure comes from pesticides used in community and home spraying.community and home spraying.

The The Ames testAmes test, ,

developed by developed by

biochemist Bruce biochemist Bruce

Ames, uses bacteria Ames, uses bacteria

to test for the to test for the

mutagenic potential mutagenic potential

of various chemicals.of various chemicals.



InfoTrac: Science That Sticks: Chemist’s InfoTrac: Science That Sticks: Chemist’s Work behind U.S. Decision to Ban PFOA. Work behind U.S. Decision to Ban PFOA. Canadian Chemical NewsCanadian Chemical News, Mar. 2006., Mar. 2006.

EPA: CarcinogensEPA: Carcinogens

Section 4Section 4

Diagnosing CancerDiagnosing Cancer


Early and accurate diagnosis of cancer is Early and accurate diagnosis of cancer is important for maximizing the success of important for maximizing the success of treatment.treatment.



There are seven general warning signs of There are seven general warning signs of cancer (CAUTION):cancer (CAUTION):


Various tests can be performed to confirm Various tests can be performed to confirm or rule out cancer.or rule out cancer.

Blood tests can detect Blood tests can detect tumor markerstumor markers, such as , such as HCG or PSA (prostate-specific antigen).HCG or PSA (prostate-specific antigen).

Radioactively labeled monoclonal antibodies Radioactively labeled monoclonal antibodies are useful in pinpointing the location and size of are useful in pinpointing the location and size of certain tumors; certain tumors; medical imagingmedical imaging techniques techniques such as MRI, X rays, ultrasound, and CT are such as MRI, X rays, ultrasound, and CT are also used to locate tumors.also used to locate tumors.


The definitive detection tool is The definitive detection tool is biopsybiopsy, removal , removal of a small piece of tissue for microscopic of a small piece of tissue for microscopic examination.examination.

A snippet of radioactively labeled DNA, called a A snippet of radioactively labeled DNA, called a DNA probeDNA probe, can be used to locate gene , can be used to locate gene mutations; however, it is expensive and usually mutations; however, it is expensive and usually not covered by insurance.not covered by insurance.

Recommended Cancer Screening TestsRecommended Cancer Screening Tests



Oncology Nursing Society: Cancer Oncology Nursing Society: Cancer SymptomsSymptoms

Mayo Clinic: Diagnosing CancerMayo Clinic: Diagnosing Cancer InfoTrac: Early Cancer Diagnosis: Present InfoTrac: Early Cancer Diagnosis: Present

and Future. Andre Baron et al. and Future. Andre Baron et al. Patient Care Patient Care for the Nurse Practitionerfor the Nurse Practitioner, Sept. 2005., Sept. 2005.

Section 5Section 5

Some Major Types Some Major Types

of Cancerof Cancer

Some Major Types of Cancer Some Major Types of Cancer

Cancers are named according to the type of Cancers are named according to the type of tissue where they are first formed.tissue where they are first formed.

SarcomasSarcomas are cancers of connective tissues. are cancers of connective tissues. CarcinomasCarcinomas arise from epithelium, including arise from epithelium, including

skin and epithelial linings of internal organs.skin and epithelial linings of internal organs. Cancers of glands are Cancers of glands are adenocarcinomasadenocarcinomas.. LymphomasLymphomas are cancers of lymph tissue. are cancers of lymph tissue. Cancer of stem cells or bone marrow is Cancer of stem cells or bone marrow is

leukemialeukemia..

Some Major Types of Cancer Some Major Types of Cancer

The following conclusions are drawn from The following conclusions are drawn from the cancer statistics in Figure 23.8.the cancer statistics in Figure 23.8.

Highest cancer incidence: male—prostate; Highest cancer incidence: male—prostate;

female—breast.female—breast. Highest cancer deaths: both male Highest cancer deaths: both male and femaleand female

—lung.—lung.

© 2007 Thomson Higher Education

Cancer Incidence by Site and Sex* Cancer Deaths by Site and Sex

MALE MALEFEMALE FEMALE

prostate232,090

lung andbronchus

93,010

colon andrectum71,820

urinary bladder47,010

non-Hodgkinlymphoma

29,070

melanoma ofthe skin33,580

oral cavity19,100

kidney22,490

leukemia19,640

pancreas16,100

all sites710,040

* Excludes basal- and squamous-cell skin cancer and in situ carcinomas except urinary bladder.

breast211,240

lung andbronchus

79,560


uterus40,880

ovary22,220

non-Hodgkinlymphoma

27,320

melanoma ofthe skin26,000


pancreas16,080

thyroid19,190

all sites662,870

lung andbronchus

90,490

prostate30,350


pancreas15,820

non-Hodgkinlymphoma

10,150

leukemia12,540

esophagus10,530

liver10,330


kidney8,020

all sites295,280

lung andbronchus

73,020

breast40,410


pancreas15,980

ovary16,210

non-Hodgkinlymphoma

9,050

leukemia10,070

uterus7,310

brain5,480

multiple myeloma5,640

all sites275,000

Fig 23.8, p.434

Video: Fighting SarcomaVideo: Fighting Sarcoma




InfoTrac: Sarcomas Most Common Cancer InfoTrac: Sarcomas Most Common Cancer Type in Teenagers. Type in Teenagers. GPGP, April 7, 2006., April 7, 2006.

InfoTrac: Mutations Point the Way to New InfoTrac: Mutations Point the Way to New Leukemia Drugs. Leukemia Drugs. Ascribe Higher Education Ascribe Higher Education News ServiceNews Service, July 17, 2006., July 17, 2006.

Abramson Cancer Center: OncolinkAbramson Cancer Center: Oncolink Association of Cancer Online Resources: Association of Cancer Online Resources:

Types of CancerTypes of Cancer

Section 6Section 6

Treating and Treating and Preventing CancerPreventing Cancer

Treating and Preventing Cancer Treating and Preventing Cancer

Chemotherapy and radiation kill cancer Chemotherapy and radiation kill cancer cells directly.cells directly.

ChemotherapyChemotherapy uses drugs to kill cancer cells. uses drugs to kill cancer cells.• The cancer drugs disrupt DNA replication during S The cancer drugs disrupt DNA replication during S

phase or prevent mitosis by inhibiting the formation phase or prevent mitosis by inhibiting the formation of the mitotic spindle.of the mitotic spindle.

• These drugs are also toxic to rapidly growing human These drugs are also toxic to rapidly growing human cells, such as hair cells, stem cells, and epithelial cells, such as hair cells, stem cells, and epithelial cells.cells.


Radiation kills both cancer cells and the healthy Radiation kills both cancer cells and the healthy cells around them.cells around them.

Adjuvant therapyAdjuvant therapy combines less-toxic combines less-toxic chemotherapy with surgery to remove the chemotherapy with surgery to remove the tumor.tumor.

Monoclonal antibodies are used to deliver lethal Monoclonal antibodies are used to deliver lethal doses of radiation or anticancer drugs to tumor doses of radiation or anticancer drugs to tumor cells specifically.cells specifically.

Immunotherapy is the use of substances such Immunotherapy is the use of substances such as interferon and interleukins to activate as interferon and interleukins to activate cytotoxic T cells to attack the cancer.cytotoxic T cells to attack the cancer.


Anticancer drugs may be matched to Anticancer drugs may be matched to genetic characteristics of cancer cells.genetic characteristics of cancer cells.

Traditional chemotherapy drugs were matched Traditional chemotherapy drugs were matched to the organ where the cancer occurs.to the organ where the cancer occurs.

New strategies aim to match therapy with the New strategies aim to match therapy with the specific genetic characteristics of the cancerous specific genetic characteristics of the cancerous cells, regardless of where the cancer occurs.cells, regardless of where the cancer occurs.


You can limit your cancer risk.You can limit your cancer risk. We cannot control heredity of some aspects of We cannot control heredity of some aspects of

biology, but we can make choices to affect our biology, but we can make choices to affect our own health.own health.

Some strategies for limiting cancer include:Some strategies for limiting cancer include:• Avoid tobacco in any form.Avoid tobacco in any form.• Maintain desirable weight.Maintain desirable weight.• Eat a low-fat, high-fiber diet.Eat a low-fat, high-fiber diet.• Restrict alcohol intake.Restrict alcohol intake.• Avoid hazardous chemicals Avoid hazardous chemicals

in the workplace.in the workplace.• Avoid excessive sun exposure.Avoid excessive sun exposure.


Video: Prostate Cancer PreventionVideo: Prostate Cancer Prevention


Useful References for Section 6 Useful References for Section 6


National Cancer Institute: Clinical TrialsNational Cancer Institute: Clinical Trials Cancer Research InstituteCancer Research Institute InfoTrac: HPV DNA Testing and HPV InfoTrac: HPV DNA Testing and HPV

Vaccines Described by Experts as Vaccines Described by Experts as Combination That Offers Best Hope of Combination That Offers Best Hope of Preventing Cervical Cancer. Preventing Cervical Cancer. PR NewswirePR Newswire, , April 27, 2006.April 27, 2006.

Section 7Section 7

Cancers of the Breast Cancers of the Breast and Reproductive and Reproductive

SystemSystem

Cancers of the Breast and Cancers of the Breast and Reproductive System Reproductive System

Breast cancerBreast cancer is a major cause of death. is a major cause of death. Breast cancer ranks second to lung cancer as a Breast cancer ranks second to lung cancer as a

cause of death in females.cause of death in females.• Causative factors include obesity, late childbearing, Causative factors include obesity, late childbearing,

early puberty, late menopause, excessive estrogen, early puberty, late menopause, excessive estrogen,

and familial history.and familial history.• Early detection by breast examination and Early detection by breast examination and

mammography are keys to cure.mammography are keys to cure. Treatment methods include Treatment methods include modified radical modified radical

mastectomymastectomy and and lumpectomylumpectomy; some drugs ; some drugs such as tamoxifen are also used.such as tamoxifen are also used.

1. Lie down and put a folded towel under your left shoulder,then put your left hand behind your head. With the right hand (fingers flat), begin the examination of your left breast by following the outer circle of arrows shown. Gently press the fingers in small, circular motions to check for any lump, hard knot, or thickening. Next, follow the inner circle of arrows. Continue doing this for at least three more circles, one of which should include the nipple. Then repeat the procedure for the right breast. For a complete examination, repeat the procedure while standing in a shower. Hands glide more easily over wet skin.

2. Stand before a mirror, lift your arms over your head, and look for any unusual changes in the contour of your breasts, such as a swelling, dimpling, or retraction (inward sinking) of the nipple.Also check for any unusual discharge from the nipple.

If you discover a lump or any other change during a breast self-examination, it’s important to see a physician at once. Most changes are not cancerous, but let the doctor make the diagnosis.

Fig 23.10b, p 436


Uterine and ovarian cancer affect women.Uterine and ovarian cancer affect women. Uterine cancerUterine cancer rates are declining due to early rates are declining due to early

detection, mainly by detection, mainly by Pap smearPap smear.. Ovarian cancerOvarian cancer is often lethal because is often lethal because

symptoms do not occur until the cancer is symptoms do not occur until the cancer is advanced; the chemical advanced; the chemical taxoltaxol has been used has been used with moderate success.with moderate success.


Testicular and prostate cancer Testicular and prostate cancer affect men.affect men.

Testicular cancerTesticular cancer is painless in is painless in its early stages but may spread its early stages but may spread to the lymph nodes and to the lymph nodes and eventually to the lungs; surgery eventually to the lungs; surgery is the usual treatment.is the usual treatment.

Prostate cancerProstate cancer is second only is second only to lung cancer in causing cancer to lung cancer in causing cancer deaths in men; a PSA blood test deaths in men; a PSA blood test is diagnostic, and cure rate is is diagnostic, and cure rate is high for cancers detected early.high for cancers detected early.


Video: Breast Cancer TreatmentVideo: Breast Cancer Treatment




InfoTrac: Tylenol Lowers Ovarian Cancer InfoTrac: Tylenol Lowers Ovarian Cancer Risk. Risk. UPI NewsTrackUPI NewsTrack, July 10, 2006., July 10, 2006.

Section 8Section 8

A Survey of Other A Survey of Other Common CancersCommon Cancers

A Survey of Other Common CancersA Survey of Other Common Cancers

Oral cancersOral cancers occur in the lips, mouth, occur in the lips, mouth, tongue, salivary glands, and throat and are tongue, salivary glands, and throat and are most common among users of any form of most common among users of any form of tobacco; most of the cancers are highly tobacco; most of the cancers are highly deadly.deadly.


Lung cancerLung cancer kills more people than any kills more people than any other cancer.other cancer.

The overwhelming risk factor is smoking, a The overwhelming risk factor is smoking, a practice that is declining in men but increasing practice that is declining in men but increasing in women.in women.

Lung cancers include Lung cancers include squamous cell squamous cell carcinomascarcinomas, , adenocarcinomasadenocarcinomas ( (large-cell large-cell carcinomascarcinomas), and ), and small-cell carcinomassmall-cell carcinomas..


Cancers of the Cancers of the stomachstomach and and pancreaspancreas are are usually adenocarcinomas of the duct cells usually adenocarcinomas of the duct cells and are usually not detected until they have and are usually not detected until they have spread.spread.


Most cancers of the colon and rectum Most cancers of the colon and rectum ((colorectal cancerscolorectal cancers) are ) are adenocarcinomas.adenocarcinomas.

The cancers generally start The cancers generally start

as small as small polypspolyps (growths). (growths). Warning signs include blood Warning signs include blood

in the feces; a family history in the feces; a family history

of colorectal cancer or of colorectal cancer or

inflammatory bowel disease inflammatory bowel disease

is a major risk factor.is a major risk factor. Figure 23.12Figure 23.12


Urinary system cancers.Urinary system cancers. Carcinomas of the Carcinomas of the kidneyskidneys and and bladderbladder are are

related to smoking and industrial chemicals.related to smoking and industrial chemicals. Wilms tumorWilms tumor is an inherited type of kidney is an inherited type of kidney

cancer that appears most often in children.cancer that appears most often in children.


Cancers of the blood and lymphatic system.Cancers of the blood and lymphatic system. Lymphomas, such as Lymphomas, such as non-Hodgkin non-Hodgkin

lymphomalymphoma, , Hodgkin’s diseaseHodgkin’s disease, and , and Burkitt Burkitt lymphomalymphoma, seem to increase with infections , seem to increase with infections that impair the immune system.that impair the immune system.

Leukemias—cancers of the stem cells of the Leukemias—cancers of the stem cells of the bone marrow—lead to overproduction of white bone marrow—lead to overproduction of white blood cells; treatment is with chemotherapy, blood cells; treatment is with chemotherapy, especially the plant derivatives especially the plant derivatives vincristinevincristine and and vinblastinevinblastine..


Skin cancers are the most common of all Skin cancers are the most common of all cancers.cancers.

Malignant melanomaMalignant melanoma, cancer of the , cancer of the melanocyte cells, metastasizes aggressively.melanocyte cells, metastasizes aggressively.

Squamous cell carcinomasSquamous cell carcinomas start out as scaly, start out as scaly, reddened bumps that grow rapidly and can reddened bumps that grow rapidly and can spread to adjacent lymph nodes.spread to adjacent lymph nodes.

Basal cell carcinomasBasal cell carcinomas grow slowly into ulcers grow slowly into ulcers with beaded margins.with beaded margins.


Basal cell carcinoma and squamous cell Basal cell carcinoma and squamous cell carcinoma are more common than malignant carcinoma are more common than malignant melanoma and can be easily treated with minor melanoma and can be easily treated with minor surgery. surgery.

Video: Skin Sun DamageVideo: Skin Sun Damage

This video clip is available in CNN Today This video clip is available in CNN Today Videos for Biology, 2003, Volume VII. Videos for Biology, 2003, Volume VII. Instructors, contact your local sales Instructors, contact your local sales representative to order this volume, while representative to order this volume, while supplies last.supplies last.

Video: Custom Cancer VaccineVideo: Custom Cancer Vaccine




InfoTrac: American Academy of Dermatology InfoTrac: American Academy of Dermatology Warns of Skin Cancer Risks This Summer; Warns of Skin Cancer Risks This Summer; More Than 1 Million New Cases of Skin More Than 1 Million New Cases of Skin Cancer to Be Diagnosed This Year in U.S. Cancer to Be Diagnosed This Year in U.S. Internet WireInternet Wire, July 7, 2006., July 7, 2006.

Mayo Clinic: Pancreatic CancerMayo Clinic: Pancreatic Cancer American Cancer Society: All About Colon American Cancer Society: All About Colon

and Rectum Cancerand Rectum Cancer

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