Increasing Cancer Risk in Patients with Nephrotic Syndrome: A Nationwide Population-based Study in Taiwan

Background: Patients with nephrotic syndrome may be at an increased risk of developing malignancies. However, the population-based evidence in Asian populations remains limited. Aim: This study aimed to evaluate whether Taiwanese patients with nephrotic syndrome are at an increased risk of developing overall and site-specific cancers. Methods: This population-based retrospective cohort study evaluated data from the Taiwan National Health Insurance database (2000–2011). A total of 10,738 patients with newly diagnosed nephrotic syndrome were identified, and each patient was randomly frequency-matched to four individuals without nephrotic syndrome based on the index year, sex, and age. A Cox multivariable proportional hazards model was used to estimate the cancer risk among patients with nephrotic syndrome. Results: The overall risk of developing cancer after the first tracking year was significantly higher in the nephrotic syndrome cohort than in the control cohort (adjusted hazard ratio: 2.655, 95% confidence interval: 1.939–5.501). Male sex, older age, and dementia contributed to the increased cancer risk. Subtype analyses indicated that patients with nephrotic syndrome also had increased risks of developing multiple myeloma, hematologic malignancies, hepatoma, and stomach, colon, kidney, and thyroid cancers. Conclusion: This nationwide study demonstrated that Taiwanese patients with nephrotic syndrome are at increased risk of both hematologic and solid malignancies, particularly after the first year of follow-up. These findings underscore the importance of vigilant cancer surveillance and timely management in patients with nephrotic syndrome.