Nonmelanoma skin carcinoma in Albuquerque, New Mexico: experience of a major health care provider.

BACKGROUND

Although nonmelanoma skin carcinomas (NMSC) are increasing nationwide, rates are difficult to measure precisely, because few registries include types of carcinoma. Albuquerque, New Mexico is a high risk site for both melanoma and NMSC. In a National Cancer Institute (NCI) survey conducted between 1977 and 1978, NMSC incidence rates among non-Hispanic white males were the highest of 8 national study sites.

METHODS

Experience with NMSC over 28.5 years at the Lovelace Health Systems in Albuquerque, New Mexico is described. The impact of multiple tumors was emphasized, recent annual incidence rates in members of the Lovelace Health Plan (LHP) were calculated, and trends in incidence rates since the NCI survey were estimated.

RESULTS

There were 10,760 tumors among 4958 people between 1964 and mid-1992, with an average of 2.2 lesions per person (range: 1-92 lesions). Basal cell carcinoma (BCC) was 6.6 times more common than squamous cell carcinoma (SCC), and more likely to be multiple. There was an excess of males among persons with each tumor type and among subjects with multiple tumors. Only 46.1% of NMSC were first tumors; multiple or subsequent tumors comprised 53.7%. More than half of the concomitant or subsequent tumors were diagnosed within 1 year of the first, but new tumors were still appearing in the same subjects more than 10 years later. The incidence of NMSC between 1989 and 1991 among LHP members increased with age, and rates were higher for non-Hispanic males than females. Hispanics had much lower rates than non-Hispanic whites (NHW), with no sex differential. Incidence rates of BCC have increased markedly since 1977 and 1978 in NHW males, and to a lesser extent in other groups. Rates of SCC have not changed. The ratio of NMSC to other carcinomas at Lovelace has doubled over the same interval and has increased 10-fold over the last 2 decades.

CONCLUSIONS

These data confirm the marked effect of age, ethnicity, and sex on NMSC rates. Differences in trends in BCC and SCC highlight their somewhat different etiologies. The increasing rate of BCC since the late 1970s and the large numbers of multiple tumors make a powerful case for intensified efforts at both primary and secondary prevention.