B-cell lymphoma arising around a PTFE graft

A 77-year-old Italian woman with end-stage renal failure of unknown origin had been on haemodialysis since 1995. Her past medical history included thalassaemia trait, erythropoietin (Epo)-resistant anaemia, asthma, depression, mixed aortic valve disease and a mastectomy for Paget’s disease of the right nipple. Haemodialysis had been performed via a right thigh PTFE loop graft since 1996. The right leg became swollen in early 2001 and she was admitted twice that year with suspected vascular access thrombosis. In September, ultrasound scanning suggested organizing haematoma and by December the loop graft was occluded. Investigations revealed both an arterial anastomosis and a venous outflow stenosis, which were dilated radiologically. Low-dose TPA was infused with good effect. Although the radiological procedure was successful with excellent flows reported, in April 2002 she was re-admitted. The right leg was tender, swollen and inflamed and a mass was palpable. Haemodialysis via the graft had failed and there was no thrill. She had been started on oral antibiotics for presumed cellulitis at her local hospital. Doppler USS showed a well-defined mass 5.8 11.1 cm in the right groin. There was no evidence of graft rupture. I.v. heparin was started. At operation, there was a substantial inflammatory reaction with marked oedema and induration around the graft: biopsies were taken. The blocked PTFE graft was partially removed with difficulty because of bleeding from multiple small vessels in the surrounding tissue. Post-operatively, the induration persisted and wound healing was slow (Figure 1). Histology showed a diffuse large B-cell lymphoma (Figures 2 and 3). A whole-body CT scan showed no evidence of disease elsewhere and it was staged 1A but she had a High-Intermediate Lymphoma Prognostic Index score. She was treated with cyclophosphamide and vincristine and four cycles of rituximab. Corticosteroids and radiotherapy were avoided because of the difficulty with wound healing. The right thigh wound healed completely after the initial chemotherapy. Chemotherapy was delayed by prolonged neutropenia after the fourth cycle. A CT scan at 4 months showed a persistent mass in the thigh (Figure 4) and a trucut biopsy showed fibrous scar tissue, a bone marrow was hypocellular and there was no evidence of lymphoma in either.