IntroductionIn general surgery and in spinal surgery, allogeneic blood transfusions (ABT) have been related to increased post-operative complications [12,13, 37, 39]. As such, reduction in ABT is a high priority in spinal surgery. Recently, techniques to reduce the need for ABT during spinal surgery have surfaced in the orthopedic surgery literature.Understanding the risk factors and costs associated with ABT can help with the discovery of new costeffective methods to reduce its burden. Several possible methods of reducing blood loss and the need for ABT associated with spinal fusion surgery currently exist. These include use of autologous pre-donation of blood [7,11,16,26, 31, 32, 40], blood dilution techniques [4,10,14,15,19,22], erythropoietin [24], use of antifibrinolytics [1,8,9,20,24,27, 30, 34, 35, 41], and use of cell salvage [6, 33]. Prior research on techniques used to reduce the need for ABT has previously been conducted in single-site hospitals or in a small number of patients enrolled in a clinical trial, which does not accurately provide a clear picture of the utilization and cost burden associated with it. The literature has not been able to provide an illustration of the current state of the use and cost of ABT in the US population.

The aim of the study was to estimate the current prevalence of advanced cutaneous malignant melanoma in 2010 in the USA and to project prevalence estimates to the year 2015. An excel-based, multicohort natural disease history model was developed. It used incidence, recurrence, all-cause mortality, and US population data from the up-to-date surveillance, epidemiology, and end results program, the US census, and the literature. The prevalence was stratified by tumor stage, sex, and age. The model estimated that there were 800 735 malignant melanoma cases (258 per 100 000 individuals) in the USA in 2010, of which 10.4% were in advanced stages including stage III (22 per 100 000 individuals) and stage IV (four per 100 000 individuals). Among these advanced cases, 58.8% were men. In total, 42.1% of patients with advanced malignant melanoma were 65 years of age and older. Of these elderly patients with an advanced stage of the disease, 65.7% were men. The total number of cases and number of advanced cases were projected to increase from 2010 to 2015 by 24.4 and 21.0%, respectively. There will be approximately one million malignant melanoma cases (306 per 100 000 individuals) in the USA in 2015. The prevalence of advanced malignant melanoma is expected to increase in the next few years. Advanced malignant melanoma disproportionately affects men and the elderly in the USA.