Intraglomerular metastasis: a necropsy study

Intraglomerular metastasis is a rare phenomenon. Four cases are reported here. The primary malignancies in these four cases were squamous cell carcinoma of the lung, adenocarcinoma of pancreas, haematological malignancy with a malignant intrapulmonary teratoma, and undifferentiated pleural mesothelioma. There was no significant renal functional impairment in any case except for mild proteinuria in one. Histopathology showed tumour cells in the mesangium, in the glomerular tufts replacing the endothelial cells, as well as in an extracapillary location replacing the parietal cells. In one case, tumour cells formed crescent-like structures. Such tumour deposits were better appreciated with special stains. The presence of intraglomerular metastasis indicates dissemination of the malignancy and hence a poor prognosis even though there is no significant impairment of renal function.