Haemangiomas in kidneys with end-stage renal disease: A novel clinicopathological association

Aims: The study of haemangiomas in end-stage renal disease (ESRD). Methods and results: Twenty ESRD nephrectomies from 16 patients (aged 9 months-68 years) were due to hypertension (four), focal segmental glomerulosclerosis (four), lupus nephritis (three), diabetes (one), IgA nephropathy (one), hereditary nephritis (one), congenital nephrotic syndrome (one) and unknown cause (one). Haemangiomas appeared as a single mass (15), two masses (one), three masses (one), four masses (two) and eight masses (one) per kidney. Tumours measured 0.2-3.5 cm. Four patients had bilateral haemangiomas. All tumours were in the medulla and often abutted renal sinus fat. All except one of the tumours were anastomosing haemangiomas, showing isolated or interconnected sinusoidal capillary-sized vascular channels lined by a single layer of benign cuboidal CD34⁺, CD31⁺, D2-40^- endothelial cells, separated by loose stroma with spindle cells. One tumour was a cellular capillary haemangioma. Intravascular growth was seen in nine specimens. All haemangiomas had extramedullary haematopoiesis. Acquired cystic kidney disease (ACKD) was seen in 11 kidneys (nine patients), renal cell carcinoma (RCC) in five, ACKD-associated RCC precursors in three, Wilms' tumour in one and papillary adenomas in five. Conclusions: Anastomosing haemangioma appears as a distinctive clinicopathological entity developing in kidneys with ESRD, with or without ACKD.