Paraneoplastic Glomerulopathy in a Case of Collecting Duct Renal Cell Carcinoma.

Paraneoplastic glomerulopathy has been described in established cases of the solid tumors of lung, gastrointestinal system, breast, etc., and rarely in patients with Renal Cell Carcinoma (RCC). Studies on secondary glomerular diseases have described a higher incidence of IgA nephropathy in patients with RCC compared to membranous glomerulopathy, which are commonly reported in malignancies of the lung and gastrointestinal tract. Collecting Duct Carcinoma (CDC), a rare high grade adenocarcinoma accounts for <1% of all renal malignancies. It arises from the cells of the collecting ducts of Bellini. We report a case of an elderly male who was diagnosed to have a disseminated CDC during his evaluation for nephrotic syndrome. Renal biopsy was suggestive of a secondary membranous glomerulonephropathy.