BACKGROUND: There is a well-known association between membranous nephropathy (MN) and cancer, and patients with MN usually are examined for cancer at the time of diagnosis. The long-term risk of cancer after MN is not well studied. STUDY DESIGN: Cohort study with record linkage between the Norwegian Kidney Biopsy Registry and Norwegian Cancer Registry. SETTING & PARTICIPANTS: 161 patients with MN from 1988 to 2003. PREDICTOR: Patients with MN compared with the age- and sex-adjusted general Norwegian population. OUTCOMES: Cancer diagnosis reported through 2003. RESULTS: Mean duration of follow-up was 6.2 years (range, 0.1 to 15 years). 33 patients developed cancer; including 24 patients with cancer after the diagnosis of MN. Median time from diagnosis of MN to diagnosis of cancer was 60 months (range, 0 to 157 months). Mean annual incidence ratio of cancer was 2.4/100 person-years (2.1/100 person-years in the 0- to 5-year period and 2.8/100 person-years for the 5 to 15 years after kidney biopsy). During the 0 to 15 years after the diagnosis of MN, the expected number of cancers was 10.7, resulting in a standardized incidence ratio of cancer of 2.25 (95% confidence interval, 1.44 to 3.35). In the 5 to 15 years after diagnosis, standardized incidence ratio was 2.30 (95% confidence interval, 1.19 to 4.02). Patients with MN who developed cancer were older (65 versus 52 years; P < 0.001). Patients with cancer and MN had a greater mortality rate than patients without cancer (67% versus 26%; P < 0.001). LIMITATIONS: Follow-up treatment after MN with cytotoxic and immunosuppressive medications is not known. CONCLUSIONS: An increased risk of developing cancer is observed after the diagnosis of MN, which persists for many years.
BACKGROUND: There is a well-known association between membranous nephropathy (MN) and cancer, and patients with MN usually are examined for cancer at the time of diagnosis. The long-term risk of cancer after MN is not well studied. STUDY DESIGN: Cohort study with record linkage between the Norwegian Kidney Biopsy Registry and Norwegian Cancer Registry. SETTING & PARTICIPANTS: 161 patients with MN from 1988 to 2003. PREDICTOR: Patients with MN compared with the age- and sex-adjusted general Norwegian population. OUTCOMES: Cancer diagnosis reported through 2003. RESULTS: Mean duration of follow-up was 6.2 years (range, 0.1 to 15 years). 33 patients developed cancer; including 24 patients with cancer after the diagnosis of MN. Median time from diagnosis of MN to diagnosis of cancer was 60 months (range, 0 to 157 months). Mean annual incidence ratio of cancer was 2.4/100 person-years (2.1/100 person-years in the 0- to 5-year period and 2.8/100 person-years for the 5 to 15 years after kidney biopsy). During the 0 to 15 years after the diagnosis of MN, the expected number of cancers was 10.7, resulting in a standardized incidence ratio of cancer of 2.25 (95% confidence interval, 1.44 to 3.35). In the 5 to 15 years after diagnosis, standardized incidence ratio was 2.30 (95% confidence interval, 1.19 to 4.02). Patients with MN who developed cancer were older (65 versus 52 years; P < 0.001). Patients with cancer and MN had a greater mortality rate than patients without cancer (67% versus 26%; P < 0.001). LIMITATIONS: Follow-up treatment after MN with cytotoxic and immunosuppressive medications is not known. CONCLUSIONS: An increased risk of developing cancer is observed after the diagnosis of MN, which persists for many years.
Authors: Jan A J G van den Brand; Peter R van Dijk; Julia M Hofstra; Jack F M Wetzels Journal: Clin J Am Soc Nephrol Date: 2014-05-22 Impact factor: 8.237