Pseudotumoral amyloidosis of β2-microglobulin origin in the buttock of a patient receiving long term haemodialysis

Abstract

A 52 year old man who had been receiving haemodialysis for 13 years, with a history of renal tuberculosis, right ischial tuberculous osteomyelitis, and dialysis arthropathy, developed a soft tissue tumour in his left buttock. Histological analysis, immunohistological staining, and electron microscopic examination of the surgically removed tumour showed massive deposits of β2,-microglobulin (β2-M) amyloid. This case shows the expanding clinical spectrum of this type of amyloidosis, and it is suggested that amyloid infiltration should be considered in the differential diagnosis of gluteal tumours in these patients.