Incidence, mortality and medical costs of patients hospitalized with melanoma in Spain: a retrospective multicentre observational study

Objective This study aimed to update and analyze the in-hospital incidence and in-hospital mortality of melanoma in Spain, to evaluate any temporal trends in both measures and to quantify the direct medical costs of specialized care that are associated to this malignancy. Methods Anonymized specialized care admission records registered between 1 Jan 2011 and 31 Dec 2017 were extracted from a Spanish nationwide hospital discharge database. Results Records included corresponded to 16,657 patients, of which 50.62% were male. In nearly 38% of all admissions secondary malignant tumors were registered, principally tumors in the lymph nodes. In-hospital incidence of melanoma was 67.5 and 58.2 per 100,000 males and females, respectively, in the study period (2011-2017), with a decreasing tendency measured after the year 2014. Mortality increased with patients' age and over time in patients over 75 years of age. In-hospital mortality was 7.73% for males and 5.29% for female patients, and was principally associated to metastatic tumors, principally in the lungs, liver and brain. Mean length of hospital stay was 4.36 days, with a readmission rate of 6.93% and a 15.70% of urgent admissions. The mean annual direct medical cost per patient was euro4175, increasing between 2014 and 2017. Conclusions The increasing in-hospital incidence of melanoma appeared to reverse in 2014, as did the increasing mortality rate measured in older males. The shift in melanoma in-hospital incidence could respond to the increasing trend to treat patients in primary care settings. Further studies will be required to confirm these trends in order to adapt the healthcare system.