Prevalence of cancer in membranous nephropathy: a systematic review and meta-analysis of observational studies.

BACKGROUND The association between membranous nephropathy (MN) and cancer has been well documented. However, the true prevalence and characteristics of cancer associated with MN have not been well described. METHODS A systematic review and meta-analysis of cohort studies was conducted to summarize the prevalence of cancer-associated MN as well as patient characteristics and types of cancer in this population. We used a random-effects meta-analysis model to estimate the prevalence of cancer. RESULTS We included 6 studies (n = 785). The estimated prevalence of cancer was 10.0% (95% CI, 6.1-14.6). The mean age of MN patients with cancer was 67 ± 7 years. The diagnosis of cancer preceded the diagnosis of MN in 20 ± 6.8%. Lung cancer was the most common type of tumor, accounting for 22 cases (26%), followed by prostate cancer (13 cases, 15%), hematologic malignancies (12 cases, 14%), colorectal cancer (9 cases, 11%), breast cancer (6 cases, 7%), and stomach and esophageal cancer (5 cases, 6%). CONCLUSION The estimated prevalence of cancer in patients with MN is 10% (95% CI, 6.1-14.6). The vast majority of tumors associated with MN are lung and prostate cancer. Hematologic malignancies should also be considered as one of the potential cancers associated with MN. Our study was based on a largely Caucasian population; therefore, the findings might not be applicable to other populations.