Nonmelanoma Skin Cancer Cases Rising in United States

New Orleans—According to a database analysis study, there were an estimated 3.7 million cases of nonmelanoma skin cancer (NMSC) in the United States in 2009. The disease cost the government $8.6 billion in 2008, and that estimate may be low because it only included costs related to Medicare. Brett M. Coldiron, MD, FACP, clinical associate professor at the University of Cincinnati, Ohio, presented the latest findings of his research at the AAD meeting. Last year, Dr. Coldiron was among the authors of an article published in Archives of Dermatology [2010;146(3):283-287] that estimated there were 3,507,693 cases of NMSC treated in the United States in 2006, affecting 2,152,500 persons (the ratio of skin cancers treated per affected patient in 2006 was 1.63). Dr. Coldiron used statistical analysis and made assumptions to determine his updated NMSC estimates. Dr. Coldiron said no national databases track NMSC, so there are no official tallies of the number of NMSC cases each year. However, because NMSC cannot be treated without a positive biopsy and the number of procedures for NMSC can be ascertained, the authors assumed that the number of procedures for NMSC provided an accurate representation for the number of actual NMSC cases. To calculate the number of NMSC procedures for 1992 and from 1996 through 2009, Dr. Coldiron and his cohorts used data sets such as the Centers for Medicare & Medicaid Services Fee-for-Service Physicians Claims database. They also examined the Medicare Limited Data Set standard analytic file 5% sample data supplied by physicians from 2002 through 2009. The 5% sample data includes claims filed for approved procedures as well as their International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes, patient ages, and the number of people receiving the services. They used the National Ambulatory Medical Care Survey to estimate NMSC-related office visits for people >65 years of age. When compiling the number of procedures, the authors added the number of approved malignant destructions, malignant excisions, and Mohs micrographic surgeries. The authors used Current Procedural Terminology codes to determine the total (17260-17266, 7270-17276, and 17280-17286 for malignant destructions; 11600-11606, 11620-11626, and 11640-11646 for malignant excisions; and 17304 for Mohs micrographic surgeries). The authors then determined the total number of procedures specific to NMSC. They multiplied the number of skin cancers by the proportion of skin cancer code claims associated with invasive nonmelanoma cutaneous malignancy (ICD-9-CM codes 173.0-173.9) and in situ malignancy (ICD-9-CM codes 232.0-232.9). They used the 5% sample data set to calculate the number of procedures per individual as well as the number of people undergoing ≥1 procedure for NMSC. The authors also calculated age-adjusted NMSC rates. However, the total data set for 1992 and 1996-2006 did not include age-stratified data, so the authors used the 5% sample data set, which stratified the ages in 5-year intervals. Dr. Coldiron said the authors assumed that 1 NMSC treatment procedure equaled 1 incident of NMSC and that the proportion of the US population >65 years of age not covered under a Medicare fee-for-service plan has the same rate of skin cancer as the people >65 years of age who are covered in a Medicare plan. In addition, they assumed the ratio of office visits for a diagnosis of NMSC to the number of procedures for NMSC was the same for people <65 years of age and for people ≥65 years of age. They also assumed the rate on NMSCs per an affected individual was the same for the entire US population and those on a Medicare fee-for-service plan. From 1992 through 2006, the total number of procedures for NMSC in the Medicare fee-for-service population increased from 1,158,298 to 2,048,517, an increase of 76.9% or an average of 4.2% per year. During that same period, the age-adjusted procedure rate per year per 100,000 Medicare beneficiaries increased from 3514 in 1992 to 6075 in 2006. Dr. Coldiron said there were 2,188,038 NMSC procedures in 2009 as well as 3,743,158 NMSCs and an age-adjusted procedure rate per year per 100,000 Medicare beneficiaries of 6892. According to Dr. Coldiron, the number of procedures for skin cancer increased 5.3% from 1999 to 2000, 7.5% from 2000 to 2001, 5.3% from 2001 to 2002, 2.8% from 2002 to 2003, 3.9% from 2003 to 2004, 5.4% from 2004 to 2005, 2.0% from 2005 to 2006, 2.4% from 2006 to 2007, 2.6% from 2007 to 2008, and 1.6% from 2008 to 2009.