Joint occurrence of Merkel cell carcinoma and non-Hodgkin lymphomas in four Nordic countries

Research output: Contribution to journalArticle


The objective of this study was to assess the reciprocal association between non-Hodgkin lymphoma (NHL) and Merkel cell carcinoma (MCC) using the data of four Nordic Cancer Registries. Data for this study were drawn from the Danish, Finnish, Norwegian, and Swedish cancer registries. Standardized incidence ratios (SIRs) for MCC among NHL patients, and for NHL among MCC patients, were calculated. There were 109 838 individuals with NHL and 1411 individuals with MCC, of which 28 had joint occurrence of NHL and MCC. In 18 cases, NHL was diagnosed first, and in 10 cases, MCC was diagnosed first. The SIR for MCC after NHL was 4.34 (95% confidence interval 2.57-6.85). The SIR for NHL after MCC was 3.13 (1.50-5.77). Although the absolute frequency of joint occurrence of MCC and NHL is low, individuals suffering from one of the cancer forms have an increased risk of the other.


  • Virve Koljonen
  • Matti Rantanen
  • Helka Sahi
  • Lene Mellemkjaer
  • Bo Terning Hansen
  • Tianhui Chen
  • Kari Hemminki
  • Eero Pukkala
External organisations
  • German Cancer Research Centre
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Cancer and Oncology


  • Merkel cell carcinoma, non-Hodgkin lymphoma, simultaneous, SIR
Original languageEnglish
Pages (from-to)3315-3319
JournalLeukemia & Lymphoma
Issue number12
Publication statusPublished - 2015
Publication categoryResearch