title: Melanoma epidemiology, prognosis and trends in Latvia.
abstract: BACKGROUND
  Melanoma incidence and mortality rates are increasing worldwide within the white population. Clinical and histological factors have been usually used for the prognosis and assessment of the risk for melanoma.
  
  
  OBJECTIVE
  The aim of the study was to describe the clinical and histopathological features of the cutaneous melanoma (CM) in the Latvian population, to test the association between melanoma features and patient survival, and to assess the time trends for melanoma incidence.
  
  
  METHODS
  We undertook a descriptive, retrospective analysis of archive data of 984 melanoma patients treated at the largest oncological hospital of Latvia, Riga East University Hospital Latvian Oncology Centre (LOC), between 1998 and 2008. Cox proportional hazards model was used to analyse patient survival and autoregressive models were applied to detect trends in melanoma incidence over time for various categories of melanoma.
  
  
  RESULTS
  The study showed a significant ascending trend in melanoma incidence in Latvia during the time period from 1998 to 2008 (ß = 1.83, 95% CI = 1.15-2.91, P = 0.011). Nodular melanoma was the most common tumour subtype with a frequency of 39.2%. Ulceration was present in 45.2% of melanomas. The mean Breslow thickness was 6.0 mm (6.8 mm) and no significant decline in median Breslow thickness was observed during the study period (P = 0.609). A better overall prognosis was detected for females in comparison with males (HR = 1.49; 95% CI = 1.22-1.81; P < 0.001).
  
  
  CONCLUSIONS
  There is a steady increase in melanoma incidence in Latvia with the majority of melanomas diagnosed at late stages with poor prognosis for survival.
authors.affiliation: Department of Oral Pathology, Riga Stradins University, Riga, LatviaLatvian Biomedical Research and Study Centre, Riga, LatviaGenetics Institute, University College London, London, UKRiga East University Hospital Latvian Oncology Centre, Riga, LatviaFaculty of Computing, University of Latvia, Riga, LatviaFaculty of Life Sciences, University of Vienna, Vienna, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Azarjana
authors.forename: A
authors.initials: A
authors.lastname: Ozola
authors.forename: D
authors.initials: D
authors.lastname: Ruklisa
authors.forename: I
authors.initials: I
authors.lastname: Cema
authors.forename: A
authors.initials: A
authors.lastname: Rivosh
authors.forename: A
authors.initials: A
authors.lastname: Azaryan
authors.forename: D
authors.initials: D
authors.lastname: Pjanova
mesh_terms: D000368:Aged; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007844:Latvia / Q000453:epidemiology; D008297:Male; D008545:Melanoma / Q000453:epidemiology* / Q000473:pathology; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000453:epidemiology* / Q000473:pathology