A 38 year old lady is troubled by lymphoedema that occurred following a block dissection of the groin for malignant melanoma many years previously. Despite therapy with compression bandages she has persistent lower leg swelling impairing her activities of daily living. She has no evidence of recurrent malignancy. Lymphoscintography demonstrates occlusion of the groin lymphatics. However, the distal lymphatic system appears healthy. Which of the following options could be considered?