How Closely Is Melanoma Survival Linked To Sun Exposure?

Marianne Berwick, PhD, MPH for the GEM Study Team Professor, Division of Epidemiology University of New Mexico, Department of Internal Medicine New Mexico Cancer Research Facility University of New Mexico, Albuquerque, NM 87131MedicalResearch.com Interview with:
Marianne Berwick, PhD, MPH for the GEM Study Team
Professor, Division of Epidemiology
University of New Mexico, Department of Internal Medicine
New Mexico Cancer Research Facility
University of New Mexico, Albuquerque, NM 87131

Medical Research: What are the main findings of this study?

Dr. Berwick: In our study of Sun Exposure and Melanoma Survival: A GEM Study we found that there is little strong evidence that sun exposure at any time in life influences melanoma-specific survival. This study took place in Australia, Italy, Canada and the United States among 3,578 individuals newly diagnosed with melanoma, who we followed for a mean of 7.4 years.

Medical Research: Were any of the findings unexpected?

Dr. Berwick: This was finding not what we had hypothesized. In an earlier study of a smaller population of 650 newly diagnosed melanoma patients in Connecticut who we followed for 5 years, we found that solar elastosis, any sunburn in life and intermittent sun exposure were all associated with better survival from melanoma.

On the other hand, in the GEM study we found several intriguing associates that need further examination:

  • (1) high UVB dose up to the age of 10 was associated with increased risk for mortality from melanoma;
  • (2) any sunburn in the 10 years up to diagnosis was associated with decreased risk for mortality from melanoma. The latter finding is more subject to recall bias due to the under-reporting of sunburn. It is possible that early life sun exposure occurs during a critical period biologically, but we have little proof for this and so this finding needs further exploration.

We also found that individuals who have been diagnosed with melanoma actually have improved overall survival with intermittent exposure, such as sunny holidays and water-related outdoor activities. It is highly likely that socioeconomic status confounds this finding as individuals with less education, who are less likely to be able to afford these activities, are at higher risk for melanoma-specific mortality.

Medical Research: What should patients and clinicians take away from this report?

Dr. Berwick: Our data indicate that clinicians should continue to advise persons to be cautious in the sun and to use protection – hats, clothing, shade and sunscreen.   Patients should follow this advice – enjoy the sun but use common sense.

Medical Research: What further research do you recommend as a result of this study?

Dr. Berwick: As a result of this study, it is clear that more biological research needs to be carried out to investigate further the role of sun exposure at different life periods and its association with melanoma mortality.

Citation:

Sun Exposure and Melanoma Survival: A GEM Study
JNCI J Natl Cancer Inst (2005) 97 (3): 195-199 doi:10.1093/jnci/dji019
Marianne Berwick, Bruce K. Armstrong, Leah Ben-Porat, Judith Fine, Anne Kricker, Carey Eberle, and Raymond Barnhil