State/National Statistics: Basic Epidemiology of Skin Cancer Presented by: Chris Johnson, MPH...

State/National Statistics:Basic Epidemiology of

Skin Cancer

Presented by: Chris Johnson, MPHEpidemiologist, Cancer Data Registry of Idaho

Cancer Awareness, Screening, and Prevention Alliance (CASPA) May 18th, 2010 7-8:30 a.m.

Huckleberry Room Central District Health Department.

Outline

• Skin• Skin Cancer

– SCC and BCC– Melanoma

• Melanoma– Risk Factors– Incidence– Stage– Survival– Mortality– Lifetime Risks– Prevention

The Skin

• The skin is the body’s largest organ. It protects against heat, sunlight, injury, and infection. It helps regulate body temperature, stores water and fat, and produces vitamin D.

• The skin has two main layers: the outer epidermis and the inner dermis.

http://www.cancer.gov/dictionary/db_alpha.aspx?expand=e#epidermis

http://www.cancer.gov/dictionary/db_alpha.aspx?expand=d#dermis

Skin Cancer

• Cancer may develop in any of the cell types:– Squamous Cell Carcinoma (SCC)– Basal Cell Carcinoma (BCC)– Melanoma

• Skin cancer is the most common form of cancer in the United States.

Squamous and Basal Cell Carcinomas

• The American Cancer Society estimates that substantially more than 1 million unreported cases of basal cell and squamous cell cancers occur annually in the US. This number is roughly equivalent to the total of all other cancer sites.

• Death rates from basal cell and squamous cell carcinomas are low.– When detected early, approximately 95% of these carcinomas can

be cured. – However, these cancers can cause considerable damage and

disfigurement if they are untreated.• Basal cell and squamous cell carcinomas are more than 10 times as

common as melanoma but account for less morbidity and mortality. – SCC may account for 20% of all deaths from skin cancer.

• SCC and BCC are not reportable to CDRI unless regional or distant stage or on a mucous membrane. – There were 5 reportable SCC and BCC skin cases in 2007 in Idaho.

• We do not know how many total cases of SCC and BCC there are per year in Idaho, but estimate it to be over 5,000.

Melanoma of the Skin• Melanoma is one of the most common cancers and the

most serious type of cancer of the skin.• Melanoma accounts for less than 5% of skin cancer

cases but causes a large majority (about 75%) of skin cancer deaths.

• The American Cancer Society estimates that about 68,720 new cases of malignant melanoma will be diagnosed in 2009, and 8,650 will die from the disease in the US.

• In some parts of the world, especially among Western countries, melanoma incidence is on the rise.– In the United States, melanoma incidence has more

than doubled in the past 30 years.• All in situ and invasive melanoma cases are reportable

to CDRI.

Melanoma Risk Factors

• Light skin color, hair color, or eye color.– Rates are more than 10 times higher in whites than in

African Americans. • Family history of skin cancer. • Personal history of skin cancer. • Intermittent exposure of untanned skin to

intense sunlight. • Severe (blistering/peeling) sunburns early in

childhood. • Presence of atypical or numerous moles (greater

than 50).• Freckles, which indicate sun sensitivity and sun

damage.

Ultraviolet Radiation

EARTH SURFACE

UV Radiation Wavelengths• Ultraviolet radiation (or UV radiation)— Electromagnetic radiation

with wavelengths between 100 and 400 nanometers. These rays are emitted from the sun and are not visible. They inflict increasingly more damage upon a recipient as the wavelength decreases. Based on its effects, UV radiation is subdivided into three wavelength ranges named UV-A, UV-B and UV-C:– UV-A covers the wavelength range 320-400 nm. UV-A is not absorbed

by the ozone layer. UV-A are present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass. Does not cause sunburn, does cause tanning. Recent research suggests its role in melanoma.

– UV-B covers the wavelength range 280-320 nm. UV-B is more energetic than UV-A, and is partially absorbed by the ozone layer. UV-B rays cause sunburn, tanning, and have been shown to cause SCC and BCC. UV-B also has the beneficial effect of vitamin-D production.

– UV-C covers the wavelength range 100-280 nm. UV-C is the most dangerous form of UV radiation, but is completely absorbed by the ozone layer. Artificial UV-C (for example emitted by electric discharges) is a threat for certain occupational group, like welders.

UV Exposure• More than 90% of skin cancers in the US are attributed

to UV-B exposure.– Other causes of skin cancer include arsenic, other chemical

exposures.• Human exposure to UV-B depends upon an individual's

– location (latitude and altitude)– the duration and timing of outdoor activities (time of

day, season of the year = angle of the sun)– and precautionary behavior (use of sunscreen,

sunglasses, or protective clothing).

UV Exposure

UV-B Exposure - Sunburn

– 33.7% of U.S. adults report having had a sunburn in 2004 (BRFSS).• In Idaho, 48.4% of white adults reported having

had a sunburn in 2008.

– Parents or caregivers reported that 72% of adolescents aged 11--18 years have had at least one sunburn, and 43% of white children aged <11 years experienced a sunburn in the past year.

SunburnPercentage of Adults who had a Sunburn in Last 12 Months

2008 Idaho BRFSS

0

10

20

30

40

50

60

70

80

90

100

Statewide HD 1 HD 2 HD 3 HD 4 HD 5 HD 6 HD 7

Per

cent

Percent

Sunburn

Percentage of Adults who had a Sunburn in Last 12 Months2008 Idaho BRFSS

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

100.0

18-24 25-34 35-44 45-54 55-64 65+

Per

cent

Percent

Synopsis of Melanoma in Idaho

• In 2007, there were 341 invasive cases of melanoma and 43 melanoma deaths among Idaho residents.

• Melanoma is the 5th most common cancer in Idaho in terms of incidence and 16th most common site for cancer deaths.

Melanoma Incidence 2007Geography Rate Count Population

Health District 1 24.1 56 208,085Health District 2 21.1 25 101,665Health District 3 28.7 64 242,205Health District 4 25.3 98 418,489Health District 5 24.4 44 173,435Health District 6 12.5 19 162,621Health District 7 11.9 20 189,645State of Idaho 23.3 341 1,496,145SEER Whites 2000 23.6 14,823 60,510,818SEER All Races 2000 20.4 15,988 78,139,539Rates are per 100,000 and age-adjusted to the 2000 US Std Population (19 age groups - Census P25-1130) standard.

Incidence by Race/EthnicityMelanoma of the Skin Incidence, 2004-2006, Combined NPCR & SEER

1.3

1.7

4.3

5.0

1.0

1.2

4.8

4.9

19.6

28.5

15.9

24.1

0.0 5.0 10.0 15.0 20.0 25.0 30.0

Female

Male

Female

Male

Female

Male

Female

Male

Female

Male

Female

Male

Asi

an/

Pac

ific

Isla

nder

Am

eric

an

Indi

an/

Ala

ska

Nat

ive

Bla

ckW

hite

,H

ispa

nic

Whi

te,

non-

His

pani

cA

ll R

ace

s

Age-Adjusted Rate per 100,000

Incidence by AgeMelanoma of the Skin Incidence, 2004-2007, Age-Specific Rates

Combined NPCR & SEER

0.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

<1

01-0

4

05-0

9

10-1

4

15-1

9

20-2

4

25-2

9

30-3

4

35-3

9

40-4

4

45-4

9

50-5

4

55-5

9

60-6

4

65-6

9

70-7

4

75-7

9

80-8

4

85+

Age Group (in years)

Rat

e p

er 1

00,0

00

Male

Female

Incidence of Invasive Melanoma by Site on

Body and Sex, United States, 2004—2006

Idaho Melanoma Incidence

1998 - 2007

Legend

Idaho Counties


0.0 - 11.6

11.7 - 17.5

17.6 - 23.0

23.1 - 27.8

Fewer than 10 cases

Health_Districts

SEER Summary Staging 2000• Cancer staging is the process of describing the

extent of the disease or the spread of the cancer from the site of origin.– In situ – noninvasive; basement membrane of

epidermis is intact (Clark’s level I)– Localized – papillary/reticular dermis invaded (Clark’s

level II-IV)– Regional – subcutaneous tissue invaded (Clark’s

level V), satellite nodules <= 2 cm from primary tumor, regional lymph nodes involved

– Distant – extension to underlying cartilage, bone, skeletal muscle, metastasis to skin or subcutaneous tissue beyond regional lymph nodes or visceral metastasis

Incident Cases by Stage

Melanoma Cases by StageNon-Hispanic Whites

100,575 852

11,616 804,987 329,987 42

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

NPCR & SEER 2004-2006 Idaho 2004-2006

Per

cen

t o

f T

ota

l C

ases

Unstaged

Distant

Regional

Localized

Melanoma Trends

Trends in Melanoma Incidence by StageSEER 9 Registries, Whites

0.0

5.0

10.0

15.0

20.0

25.0

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

Year of Diagnosis

Ag

e-A

dju

sted

Rat

e p

er

100,

000

Localized Rate

Advanced Rate

Ratio

Cancer Survival

Site % Survival Site % SurvivalAll Sites 66.2% Kidney and Renal Pelvis 66.1%Thyroid 97.4% Larynx 62.5%Prostate 95.8% Colorectal 62.3%Testis 94.0% Leukemia 51.6%Breast 90.9% Ovary 44.4%Melanoma of the Skin 87.6% Myeloma 34.6%Hodgkin Lymphoma 86.3% Brain - malignant 32.4%Corpus Uteri 83.6% Stomach 25.8%Bladder 75.9% Esophagus 16.1%Non-Hodgkin Lymphoma 70.5% Lung and Bronchus 13.9%Cervix 69.2% Liver and Bile Duct 8.6%Oral Cavity and Pharynx 67.7% Pancreas 5.9%

5-Year Relative Cancer Survival, 2000-2007 Idaho Cases

Melanoma Survival by Stage

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

1 2 3 4 5 6 7 8 9 10

Years Survival

Per

cen

t R

elat

ive

Su

rviv

al

Localized SEER 1997-2007

Localized Idaho 1997-2007

Regional SEER 1997-2007

Regional Idaho 1997-2007

Distant SEER 1997-2007

Distant Idaho 1997-2007

Melanoma Mortality 2004-2008Geography Rate Count Population

Health District 1 3.7 43 1,014,918Health District 2 2.7 15 507,235Health District 3 3.4 37 1,166,718Health District 4 3.5 62 2,018,142Health District 5 2.9 26 855,843Health District 6 2.9 21 809,462Health District 7 2.9 22 923,282State of Idaho 3.2 226 7,295,600US Whites 2006 3.1 8,250 241,574,020US All Races 2006 2.7 8,441 298,754,819Rates are per 100,000 and age-adjusted to the 2000 US Std Population (19 age groups - Census P25-1130) standard.

Leading Causes of Mortality and Melanoma - Males

4.7

22.6

25

25.8

27.3

38.8

48.4

57.5

58.2

120.4

183.4

191

822.4

4.1

18.4

27.5

23.6

18.0

44.0

67.5

55.2

47.9

113.2

249.2

221.1

927.50

0 100 200 300 400 500 600 700 800 900 1000

Melanoma of the Skin

Alzheimers

Diabetes Mellitus

Prostate Cancer

Suicide

Cerebrovascular Diseases

Lung Cancer

Accidents and Adverse Effects

Chronic Obstructive Pulmonary Disease and Allied Cond

Other Cause of Death

Diseases of Heart

All Malignant Cancers

All Causes of Death


US 2006

Idaho 2008

2.2

14.5

21.8

22.3

27.7

28.6

37.1

39.2

39.9

111.9

126

147.5

630.4

1.7

14.5

23.4

20.1

24.3

25.4

40.2

42.2

35.8

96.2

160.9

153.7

654.1

0 100 200 300 400 500 600 700

Melanoma of the Skin

Colon and Rectum

Breast Cancer

Diabetes Mellitus

Alzheimers

Accidents and Adverse Effects

Lung Cancer

Cerebrovascular Diseases

Chronic Obstructive Pulmonary Disease and Allied Cond

Other Cause of Death

Diseases of Heart

All Malignant Cancers

All Causes of Death


US 2006

Idaho 2008

Leading Causes of Mortality and Melanoma - Females

Mortality Trends

0

0.5

1

1.5

2

2.5

3

3.5

4

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

Year

Ag

e-A

dju

sted

Rat

es

Idaho

US

Risks of Developing and Dying from Melanoma

If your currentage is:

30 1 in 689 1 in 257 1 in 124 1 in 69 1 in 45 1 in 3540 1 in 404 1 in 149 1 in 76 1 in 47 1 in 3750 1 in 229 1 in 91 1 in 51 1 in 3960 1 in 140 1 in 62 1 in 4470 1 in 95 1 in 5580 1 in 87



Melanoma in Males

Then your risk of developing melanoma by a particular age is:

By age 40 By age 50 By age 60 By age 70 By age 80 Ever

Then your risk of dying from melanoma by a particular age is:


Risks of Developing and Dying from Melanoma





Melanoma in Females

Then your risk of developing melanoma by a particular age is:


Then your risk of dying from melanoma by a particular age is:


Preliminary Results from CDC Melanoma Monograph

• Many papers, many authors

• A few preliminary results:• Socio-economic status (SES)• Physician per county population

– Relationship to incidence differs by stage at time of diagnosis

Melanoma & SES

• SES measures contribute substantially to variation in cutaneous melanoma incidence and mortality.

• Patients with higher SES measures are more likely to be diagnosed with melanoma.

• However, patients with lower SES measures are more likely to have an advanced stage at diagnosis, and worse outcomes, including higher mortality.

• Complex relationship between:– socioeconomic factors, environmental risk factors and sun

exposure behavior, – awareness of melanoma prevention, access to primary care and

melanoma screening, – potential variation in ultraviolet exposure related to differences in

outdoor recreation and leisure, a product of SES itself.

Melanoma & SESLocalized Stage Cutaneous Melanoma Incidence & SES

Incidence Density Ratios non-Hispanic Whites, Combined NPCR & SEER 2004-2006

0.6

1.0

1.4

75-<

85 v

s<

75

85+

vs

<75

10-<

20 v

s<

10

20+

vs

<10

35,0

00-

49,9

99 v

s<

35,0

00

50,0

00+

vs

<35

,000

Met

rop

oli

tan

vs u

rban

Ru

ral

vsu

rban

<5

vs >

10

5-10

vs

>10

% >= High schooleducation (race-

specific)

% Below poverty level(race-specific)

Median householdincome

Urban-rural status % Unemployed

County- (*Race) Based SES Measure

IDR

Melanoma & Physician DensityCutaneous Melanoma Incidence & Physicians per County Population

Incidence Density Ratios non-Hispanic Whites, Combined NPCR & SEER 2004-2006

0.6

1.0

1.4

Localized Stage Advanced Stage Localized Stage Advanced Stage Localized Stage Advanced Stage

Dermatologists per 10,000 Internal Medicine per 10,000 General Practitioner per 10,000

Estimated County Physician Density

IDR

Prevention of Melanoma

• Primary Prevention– Avoiding the disease in the first place

• Secondary Prevention– Screening– Early diagnosis and treatment

Primary Prevention• Skin cancer is largely preventable when sun protection measures

against UV rays are used consistently.• Preventing sunburn, especially in childhood, may reduce the lifetime

risk for melanoma.

Recommendations: – Avoid exposure to the midday sun (from 10 a.m. to 4 p.m.) whenever

possible. When your shadow is shorter than you are, remember to protect yourself from the sun.

– If you must be outside, wear long sleeves, long pants, and a hat with a wide brim.

– Protect yourself from UV radiation that can penetrate light clothing, windshields, and windows.

– Protect yourself from UV radiation reflected by sand, water, snow, and ice.

Sunscreen• Sunscreen's role in preventing skin cancer has been demonstrated

to be complex.• Using sunscreen has been shown to prevent squamous cell and

basal cell skin cancers. • Sunscreens May Not Reduce the Risk of Cutaneous Melanoma

– The evidence for the effect of sunscreen use in preventing melanoma is mixed.

– The conflicting results may reflect the fact that sunscreen use is more common among fair-skinned people, who are at higher risk for melanoma;

– or, this finding may reflect the fact that sunscreen use could be harmful if it encourages longer stays in the sun without protecting completely against cancer-causing radiation.

• Some sunscreens only protect against UVB radiation.• Sunscreen also blocks vitamin D formation in the skin, a process

that some researchers believe also promotes cancer.

• To date, no criteria exist in the U.S. for measuring and labeling the amount of UVA defense a sunscreen provides. However, the FDA plans to introduce UVA standards within the next few years.

Recent Sunscreen Research• A recent meta-analysis found consistently that sunscreen users above 40

degrees latitude are at a higher risk of melanoma than people who don't use sunscreen, even when differences in skin color are taken into account.

• Wearing sunscreen decreased melanoma risk in studies closer to the equator.

• In the Northern hemisphere, 40 degrees draws a line between New York city and Beijing.

• The UV light that reaches the Earth's surface is composed of UVA (longer) and UVB (shorter) wavelengths. UVB causes sunburn, while they both cause tanning. Sunscreen blocks UVB, preventing burns, but most brands only weakly block UVA. Sunscreen allows a person to spend more time in the sun than they would otherwise, and attenuates tanning. Tanning is a protective response (among several) by the skin that protects it against both UVA and UVB. Burning is a protective response that tells you to get out of the sun. The result of diminishing both is that sunblock tends to increase a person's exposure to UVA rays.

• It turns out that UVA rays are more closely associated with melanoma than UVB rays, and typical sunscreen fails to prevent melanoma in laboratory animals.

http://www.ncbi.nlm.nih.gov/pubmed/18022535

http://www.ncbi.nlm.nih.gov/pubmed/12875796

http://jnci.oxfordjournals.org/cgi/content/abstract/86/2/99

Ultraviolet-B (UVB)-vitamin D-cancer hypothesis

• UVB-induced vitamin-D may decrease the rates of some cancers.• Several ecological and observational studies have examined the

hypothesis, in addition to one good randomized, controlled trial. • Results for breast and colorectal cancer satisfy the criteria best, but

there is also good evidence that other cancers do as well, including bladder, esophageal, gallbladder, gastric, ovarian, rectal, renal and uterine corpus cancer, as well as Hodgkin's and non-Hodgkin's lymphoma.

• Several cancers have mixed findings with respect to UVB and/or vitamin D, including pancreatic and prostate cancer and melanoma. Even for these, the benefit of vitamin D seems reasonably strong.

• The action spectrum of ultraviolet radiation mainly responsible for melanoma induction is unknown, but evidence suggests it could be ultraviolet A (UVA), which has a different geographic distribution than ultraviolet B (UVB).

Sun Exposure: UV-B• A number of public health organizations state that there

needs to be a balance between having the risks of having too much (skin cancer) and the risks of having too little sunlight (vitamin-D deficiency).

• There is a general consensus that sunburn should always be avoided.

• However, not all physicians agree with the assertion that there is an optimal level of sun exposure, with some arguing that it is better to minimize sun exposure at all times and to obtain vitamin D from other sources.

• Serum levels of 25(OH) D3 are below the recommended levels for a large portion of the general adult population and in most minorities, indicating that Vitamin D deficiency is a common problem in the United States.

http://en.wikipedia.org/wiki/Sunburn

Tanning Beds• Tanning beds primarily emit UVA. The lamps used in tanning salons

emit doses of UVA as much as 12 times that of the sun.• Use of sunbeds (with deeply penetrating UVA rays) has been linked

to the development of skin cancers, including melanoma.

• In July 2009, the IARC released a report that categorized tanning beds as “carcinogenic to humans.” The agency, which is part of the World Health Organization (WHO), previously classified tanning beds as “probably carcinogenic.” The change comes after an analysis of more than 20 epidemiological studies indicating that people who begin using tanning devices before age 30 are 75% more likely to develop melanoma.

• The World Health Organization recommends that no person under 18 should use a sunbed.

http://en.wikipedia.org/wiki/Sunbed

http://en.wikipedia.org/wiki/International_Agency_for_Research_on_Cancer

http://en.wikipedia.org/wiki/World_Health_Organization

Secondary Prevention

• Self Skin Examinations• Medical Skin Examinations

Cost-Effectiveness of Screening for Malignant Melanoma

• Journal of the American Academy of Dermatology. 41(5, Part 1):738-745, November 1999.

• The cost-effectiveness ratio for a screening program of adults older than age 20 who were at high risk for skin cancer was about $30,000 per year of life saved.

• This is reasonably cost-effective compared with other accepted cancer screening strategies.

State/National Statistics: Basic Epidemiology of Skin Cancer Presented by: Chris Johnson, MPH...

Documents

Transcript of State/National Statistics: Basic Epidemiology of Skin Cancer Presented by: Chris Johnson, MPH...