Trends in incidence, mortality and survival of testicular cancer patients in Belarus

Abstract

Introduction: The objective of this study was to assess recent trends in incidence, mortality and relative survival (RS) in testicular cancer (TC) patients in Belarus and to provide international comparisons of our figures.

Material and methods: We surveyed the Belarusian Cancer Registry for all male cases diagnosed with International Classification of Diseases for Oncology, third edition (ICD-O-3) topography code C62 between 1990 and 2015. Trends for incidence and mortality rates per 100,000 of the world standard population and annual percentage changes (APCs) were calculated. We also estimated the 1- and 5-year RS rates for the 1990-1998, 1999-2007 and 2008-2015 periods according to the Ederer II method. The RS estimates for the 2008-2015 period were age-standardized and compared with the published EUROCARE-5 data and SEER-18 database analysis.

Results: A total of 2,500 and 2,439 cases were included into incidence and survival analyses, respectively. We found a significant increase in the TC age-standardized incidence rate (APC 2.6%) and a decline in the age-standardized mortality (APC -3.0%) over the study period. RS significantly increased in all patients` strata; a relative increase was more pronounced in advanced stages of seminoma and younger age groups. Nevertheless, the most recent figures of age-standardized RS including stage-specific estimates were generally worse than the European and SEER data.

Conclusions: We have found a significant increase in TC incidence in Belarus in recent years. Mortality has significantly declined with a corresponding increase in RS which, however, did not reach European or North American figures. Continued effort is required to improve the quality of management of TC patients in our country.

Keywords: incidence; mortality; proportional hazards models; survival analysis; testicular germ cell tumor; testicular neoplasms.

Figure 1

Smoothed trends for age-standardized incidence and mortality rates for testicular cancer in Belarus, 1990-2015: (A) in total cohort, (B) by histologic variant.

Figure 2

Smoothed trends for stage-specific age-standartized incidence rates for testicular cancer in Belarus, 1990–2015.

Figure 3

Smoothed trends for age-specific age-standartized incidence rates for testicular cancer in Belarus, 1990–2015.

Figure 4

Smoothed trends for stage-specific age-standartized mortality rates for testicular cancer in Belarus, 1990–2015.

Figure 5

Smoothed trends for age-specific age-standartized mortality rates for testicular cancer in Belarus, 1990–2015.

Figure 6

Trends for relative survival (RS) estimates (%) with 95% confidence intervals according to histologic variant of testicular cancer in Belarus, 1990–2015.

Figure 7

Trends for relative survival (RS) estimates (%) with 95% confidence intervals according to extent of disease in seminoma testicular cancer patients in Belarus, 1990–2015.

Figure 8

Trends for relative survival (RS) estimates (%) with 95% confidence intervals according to extent of disease in non-seminoma testicular cancer patients in Belarus, 1990–2015.

Figure 9

Age-specific for relative survival estimates (%) with 95% confidence intervals in testicular cancer patients in Belarus, 1990–2015.

Figure 10

Trends for 1-year relative survival estimates (%) with 95% confidence intervals according to region and place of residence in testicular cancer patients in Belarus, 1990–2015.

Figure 11

Trends for 5-year relative survival estimates (%) with 95% confidence intervals according to region and place of residence in testicular cancer patients in Belarus, 1990–2015.

Figure 12

Comparison of 5-year age-standardized relative survival rates (%) with 95% confidence intervals for Belarus (2008–2015): (A) with other European regions (1999–2007) from the EUROCARE-5 study [12], (B) with the SEER-18 database (2008–2015). ‡ – non-standardized estimates, § – 36-month estimate, # – 46-month estimate