[Skin cancer incidence in Zacatecas]. / Incidencia de cáncer de piel en Zacatecas.

BACKGROUND: Skin cancer is the most frequent cancer related to ultraviolet radiation. The aim was to estimate the incidence of skin cancer type, melanoma and non-melanoma in Zacatecas, Mexico. METHODS: An epidemiological study was carried out during the period from 2008 to 2012. The data were obtained from the Instituto Mexicano del Seguro Social (IMSS), Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), Secretaría de Salud de Zacatecas (SSZ) and a private source, the Centro Médico Alameda. The incidence and the global prevalence were estimated. RESULTS: We studied 958 skin cancer cases, histopathologically confirmed. The cases were distributed as: 63.6 % basal cell carcinomas, 25.8 % squamous cell carcinomas, and 10.6 % melanoma. Significantly higher proportions were observed in women in the basal cell carcinomas (60.4 %) and squamous cell carcinomas (53.4 %). However, in the case of melanoma, the major proportion was observed in men (55.9 %). The more frequent skin cancer location was the face and for basal cell carcinoma was the nose (53 %); for squamous cell carcinomas were the lips (36 %), and for melanoma it was also the nose (40 %). The skin cancer incidence was estimated in 20 cases for each 100 000 inhabitants. Linear regression analysis showed that the skin cancer is increasing at an annual rate of 10.5 %. CONCLUSIONS: The anatomical location indicates that solar UV radiation is a risk factor, since the face is the zone with major exposure to solar radiation.

INTRODUCCIÓN: el cáncer de piel es una neoplasia relacionada con la radiación ultravioleta solar. El objetivo fue estimar la incidencia del cáncer de piel de tipo melanoma y no-melanoma. MÉTODOS: se llevó a cabo un estudio epidemiológico entre 2008 y 2012 en Zacatecas, México. La información se obtuvo de los registros confirmados de cáncer de piel en el Instituto Mexicano del Seguro Social, el Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, la Secretaría de Salud de Zacatecas y el laboratorio privado del Centro Médico Alameda. Se calculó la incidencia y la prevalencia global. RESULTADOS: se estudiaron 958 casos de cáncer de piel: 63.6 % de carcinoma basocelular, 25.8 % de espinocelular y 10.6 % de melanoma. Se observó una mayor prevalencia de mujeres: 60.4 % en carcinoma basocelular y 53.4 % en carcinoma espinocelular. En el melanoma prevalecieron los hombres (55.9 %). La región anatómica donde predominó el cáncer de piel fue la cara: la nariz (53 %) en carcinoma basocelular, los labios (36 %) en carcinoma espinocelular y la nariz (40 %) en melanoma. La incidencia estimada fue 20 casos por cada 100 000 habitantes. El análisis de regresión lineal mostró que el cáncer de piel se incrementa 10.5 % anualmente. Conclusiones: la ubicación de las lesiones sugiere que un factor de riesgo es la exposición a los rayos solares UV.

Daily doses of biologically active UV radiation retrieved from commonly available parameters.

A multiple linear correlation is done between atmospheric transmissivity for four biologically active radiation daily doses (UVB, erythemal, DNA and plant damage) T, and three parameters (daily sunshine fraction sigma, cosine of the daily minimum solar zenith angle mu min and daily total ozone column omega). T is defined as the ratio of a daily dose to its extra-atmospheric value. The data used are spectral UV measurements (390-400 nm at 0.5 nm step) recorded along year 2000 and over 8 months of year 2001 at Briançon Station (Alps, 1300 m above sea level) that forms part of the French UV network. The coefficients obtained from year 2000 correlation permit to retrieve daily doses for year 2001 with an average error running from 3 to 9% for monthly mean values and from 2 to 4.5% for 3-monthly mean values, depending on daily dose type. The retrieval of yearly mean value gives an error between 4 and 7.5%. Retrieving the daily dose of a given day, where sigma > or = 0.2, introduces error running from 16 to 32% depending on daily dose. An attempt to retrieve the yearly mean UVB daily dose for a northern France site, from the previous coefficients, gives encouraging results.