Letters Section Editor: Robert M. Golub, MD, Senior Editor.
To the Editor: The study by Dr Christenson and colleagues1 demonstrated an increased incidence of basal cell and squamous cell carcinomas in a population younger than 40 years. We are concerned about the generalizability of their findings to persons living in other parts of the United States.
Olmsted County, Minnesota, is in a high-latitude area, and residents thus have less direct sunlight exposure compared with other areas, such as California, Texas, and Florida. Regions located in a lower latitude would be expected to have an even higher incidence of basal cell and squamous cell carcinomas in a younger population. Australia, which is very close to the equator, has one of the highest incidences of nonmelanoma skin cancer in the world.2 Additional studies are required to examine the effects of latitude (and, consequently, more sunlight exposure) on the development of basal cell and squamous cell carcinomas in younger populations.
Wu JJ, Behnam SE, Fife DJ, Huang DB. Basal Cell and Squamous Cell Carcinoma in Persons Younger Than 40 Years. JAMA. 2006;295(3):278-281. doi:10.1001/jama.295.3.278-c