Last updated on March 15, 2014 at 21:56 EDT  Melanoma risk only
partially associated vith exposure to UVB from sunlight
December 21, 2005   The report in the Dec. 21 issue of the
Journal of the National Cancer Institute also indicates that
only nonmelanoma skin cancers (i.e., basal and squamous cell
carcinomas) are strongly associated with exposure to UVB
radiation.   “Although we have refined the common wisdom that
excess sun exposure is always associated with increased risk of
skin cancer, the take-home message for the public is still the
same Ã¢Ë†´ limit sun exposure and use a sunscreen that blocks
both UVA and UVB rays,” says the study’s lead investigator,
Qingyi Wei, M.D., Ph.D., professor in the Department of
Epidemiology.  The study is a painstaking analysis of the
ability of UVB radiation to damage a cell’s chromosomes.
Chromosomal injury is one way cells can become cancerous; damage
to the genes that make up the chromosome is another, and Wei and
his colleagues already have shown in previous studies