title: Changes in Tumor Characteristics in Kidney Transplanted Patients Over the Last 40 Years.
abstract: BACKGROUND
  Post-transplantation tumors (PTTs) are the greatest limiting factor for patient survival following organ transplantation.
  
  
  OBJECTIVE
  To describe the incidence and main characteristics of malignancies developed in patients who underwent kidney transplantation in Budapest between 1973 and 2014.
  
  
  METHODS
  During this period, the essential data for PTTs were repeatedly evaluated. In this study, the results from 1990, 1995, 2000, 2006, and 2013 were evaluated.
  
  
  RESULTS
  Incidence of PTTs increased from 2.3% to 11.1%. Male/female ratio was 2:1. Skin, native kidney, and lung cancers were the most common tumors during the entire observation period. Lymphoma was seen rarely at the beginning and became common in 2013. The same was observed in the most frequent general population tumors (colorectal, breast, hepatic, prostate, gastric cancer, and malignant melanoma) where the occurrence increased in the last 10 years. Mean age of patients increased from 35.7 to 56.5 years. During the last 20 years, age of recipients increased: above 50 years from 22.9% to 40.5%, and above 60 years from 8.2% to 23.1%. Patient survival was different according to tumor stage at discovering, i.e. renal cell carcinoma was usually discovered in stage I. resulting in a 66.1% 5-year survival rate, whereas 43.5% of colorectal cancers were diagnosed in stage IV, with a 13.9% 5-year survival rate.
  
  
  CONCLUSIONS
  The frequency of PTTs and proportion of elderly persons undergoing transplants are continuously increasing. Tumor stage is a determining factor for patient survival. Recognition of precancerous conditions, diagnosis of tumors in early stage, and oncological screening can improve survival time.
authors.affiliation: Department of Transplantation and Surgery, Semmelweis University, Budapest, Hungary. Electronic address: vegso.gyula@med.semmelweis-univ.hu.
authors.forename: G
authors.initials: G
authors.lastname: Végső
authors.affiliation: Department of Transplantation and Surgery, Semmelweis University, Budapest, Hungary.
authors.forename: A
authors.initials: A
authors.lastname: Tóth
authors.affiliation: Department of Transplantation and Surgery, Semmelweis University, Budapest, Hungary.
authors.forename: É
authors.initials: É
authors.lastname: Toronyi
authors.affiliation: Department of Transplantation and Surgery, Semmelweis University, Budapest, Hungary.
authors.forename: F
authors.initials: F
authors.lastname: Perner
authors.affiliation: Department of Transplantation and Surgery, Semmelweis University, Budapest, Hungary.
authors.forename: Z
authors.initials: Z
authors.lastname: Máthé
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D006814:Hungary / Q000453:epidemiology; D015994:Incidence; D016030:Kidney Transplantation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D017678:Sex Distribution; D016019:Survival Analysis