Ambient UV, personal sun exposure and risk of multiple primary melanomas.
OBJECTIVE
Sun exposure is the main cause of melanoma in populations of European origin. No previous study has examined the effect of sun exposure on risk of multiple primary melanomas compared with people who have one melanoma.


METHODS
We identified and enrolled 2,023 people with a first primary melanoma (controls) and 1,125 with multiple primary melanomas (cases) in seven centers in four countries, recorded their residential history to assign ambient UV and interviewed them about their sun exposure.


RESULTS
Risk of multiple primary melanomas increased significantly (P<0.05) to OR=2.10 for the highest exposure quarter of ambient UV irradiance at birth and 10 years of age, to OR=1.38 for lifetime recreational sun exposure, to OR=1.85 for beach and waterside activities, to OR=1.57 for vacations in a sunnier climate, to OR=1.50 for sunburns. Occupational sun exposure did not increase risk (OR=1.03 for highest exposure). Recreational exposure at any age increased risk and appeared to add to risk from ambient UV in early life.


CONCLUSIONS
People who have had a melanoma can expect to reduce their risk of a further melanoma by reducing recreational sun exposure whatever their age. The same is probably true for a person who has never had a melanoma.
Kricker
Anne
A
School of Public Health, University of Sydney, Edward Ford Building A27, NSW, 2006, Australia, and Women's College Hospital, Toronto, ON, Canada. annek@health.usyd.edu.au
Armstrong
Bruce K
BK
Goumas
Chris
C
Litchfield
Melisa
M
Begg
Colin B
CB
Hummer
Amanda J
AJ
Marrett
Loraine D
LD
Theis
Beth
B
Millikan
Robert C
RC
Thomas
Nancy
N
Culver
Hoda Anton
HA
Gallagher
Richard P
RP
Dwyer
Terence
T
Rebbeck
Timothy R
TR
Kanetsky
Peter A
PA
Busam
Klaus
K
From
Lynn
L
Mujumdar
Urvi
U
Zanetti
Roberto
R
Berwick
Marianne
M
D000293:Adolescent; D000328:Adult; D002648:Child; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000209:etiology*; D008875:Middle Aged; D009378:Neoplasms, Multiple Primary / Q000209:etiology*; D009381:Neoplasms, Radiation-Induced; D016273:Occupational Exposure; D016017:Odds Ratio; D011829:Radiation Dosage; D012307:Risk Factors; D040242:Risk Reduction Behavior; D012878:Skin Neoplasms / Q000209:etiology*; D013472:Sunlight / Q000009:adverse effects*; D014466:Ultraviolet Rays / Q000009:adverse effects*