Cancer before and after the start of hemodialysis and association with mortality - an Eastern-European multicenter study.

Introduction: East-European data on cancer in patients undergoing hemodialysis (HD) are scarce. This study aimed to assess the pattern of cancer and related mortality in patients with end-stage kidney disease (ESKD) undergoing HD.
Methods: Retrospectively analyzing data from 7 HD centers, this study examined 1377 incident HD patients divided into three groups: no-cancers (NoC), cancers that occurred prior to HD initiation (CPI) and de novo cancer developed after HD initiation (DNC). Mortality risk and survival trends within groups were analyzed using Cox regression and Kaplan-Meier methods.
Results: In the cohort, 89.46% of the patients had no cancer (NoC group), 3.63% had cancer before (CPI group), and 6.89% had cancer after HD initiation (DNC group). The mean time from HD initiation to DNC diagnosis was 1 [2.75] years. Older age was associated with a higher risk of developing DNC ( p  < 0.001). Chronic tubulointerstitial nephritis (CTIN) is more prevalent in cancer patients. The most common cancer sites among DNC patients were the digestive (29.47%) and urinary tracts (18.95%), while those in CPI subjects were hematologic (22%) and digestive (20%). Cancer was an independent predictor of mortality risk (HR = 6.9, 95% [CI]:4.5-10.6, p  < 0.001).
Conclusions: East-European ESKD patients undergoing HD have a high incidence of de novo cancers whose primary cancer sites are the digestive and urinary tracts. Almost half of the HD patients with CPI have hematologic and digestive tract cancers. Age and CTIN were associated with cancer risk. Cancer is an independent risk factor for all-cause mortality in patients undergoing hemodialysis (HD).