Paraneoplastic Glomerulopathies: Mechanistic and Pathogenic Insights

Paraneoplastic glomerular diseases are triggered by substances secreted by tumor cells, such as tumor antigens, rather than direct tumor invasion, with membranous nephropathy being the most observed lesion. These conditions often manifest as proteinuria, hematuria, and/or varying levels of kidney dysfunction. In some cases, the initial presentation may precede the diagnosis of malignancy and can be indistinguishable from the idiopathic glomerulopathies, requiring a high level of clinical suspicion to accurately identify a paraneoplastic origin. Although the exact pathophysiologic mechanisms underlying paraneoplastic glomerulopathy are not fully understood, they are thought to involve an immune-mediated response to tumor antigens in most cases. Recognizing paraneoplastic glomerulopathies is of significant clinical importance, as their management is distinct and has substantial implications for the treatment of the associated malignancy.