We conducted a retrospective National Cancer Registry study in Austria to assess a possible seasonal variation in the clinical diagnosis of testicular germ cell tumors (TGCT). In total, 3615 testicular cancer diagnoses were identified during an 11-year period from 2008 to 2018. Rate ratios for the monthly number of TGCT diagnoses, as well as of seasons and half-years, were assessed using a quasi-Poisson model. We identified, for the first time, a statistically significant seasonal trend (p < 0.001) in the frequency of monthly newly diagnosed cases of TGCT. In detail, clear seasonal variations with a reduction in the tumor incidence during the summer months (Apr-Sep) and an increase during the winter months (Oct-Mar) were observed (p < 0.001). Focusing on seasonality, the incidence during the months of Oct-Dec (p = 0.008) and Jan-Mar (p < 0.001) was significantly higher compared to the months of Jul-Sep, respectively. Regarding histopathological features, there is a predominating incidence in the winter months compared to summer months, mainly concerning pure seminomas (p < 0.001), but not the non-seminoma or mixed TGCT groups. In conclusion, the incidence of TGCT diagnoses in Austria has a strong seasonal pattern, with the highest rate during the winter months. These findings may be explained by a delay of self-referral during the summer months. However, the hypothetical influence of vitamin D3 in testicular carcinogenesis underlying seasonal changes in TGCT diagnosis should be the focus of further research.
Cancers. 2021 Oct 27*** epublish ***
Gennadi Tulchiner, Nina Staudacher, Josef Fritz, Monika Hackl, Martin Pichler, Maximilian Seles, Shahrokh F Shariat, David D'Andrea, Kilian Gust, Walter Albrecht, Karl Grubmüller, Stephan Madersbacher, Sebastian Graf, Lukas Lusuardi, Herbert Augustin, Andreas Berger, Wolfgang Loidl, Wolfgang Horninger, Renate Pichler
Department of Urology, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria., Department of Medical Statistics, Informatics and Health Economics, Medical University of Innsbruck, Schöpfstraße 41, 6020 Innsbruck, Austria., Austrian National Cancer Registry, Statistics Austria, 1110 Vienna, Austria., Research Unit of Non-Coding RNAs and Genome Editing in Cancer, Comprehensive Cancer Center Graz, Division of Clinical Oncology, Department of Internal Medicine, Medical University of Graz, 8036 Graz, Austria., Department of Urology, Medical University of Graz, 8036 Graz, Austria., Department of Urology, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria., Department of Urology, Austria and Public Health Agency of Lower Austria, 2130 Mistelbach, Austria., Department of Urology and Andrology, University Hospital Krems, Karl Landsteiner University of Health Sciences, 3500 Krems, Austria., Department of Urology and Andrology, Kaiser-Franz-Josef Spital, 1100 Vienna, Austria., Department of Urology, Johannes Kepler University Linz, 4040 Linz, Austria., Department of Urology and Andrology, Paracelsus Medical University Salzburg, Müllner Hauptstrasse 48, 5020 Salzburg, Austria., Department of Urology, General Hospital of the City of Klagenfurt, 9020 Klagenfurt, Austria., Department of Urology, Academic Teaching Hospital Feldkirch, 6800 Feldkirch, Austria., Department of Urology, Ordensklinikum Linz GmbH Elisabethinen, 4020 Linz, Austria.