Clinicopathologic Characteristics of Intraglomerular Malignancy in Kidney Biopsies

IGM is a rare presentation of disseminated malignancy, often indicating advanced disease with poor prognosis. Nephropathologists should be aware of IGM as a histologic mimicker of endocapillary hypercellularity or cellular crescent formation. Similarly, the provision of complete clinical history is critical for accurate biopsy assessment and to avoid this diagnostic pitfall. Given its high mortality rate and the short interval between tissue diagnosis and death, the identification of IGM should prompt urgent medical attention.