LYMPHANGIOMATOSIS OF THE LIMBS - CLINICOPATHOLOGICAL ANALYSIS OF A SERIES WITH A GOOD PROGNOSIS

Six cases of a distinctive but poorly recognized variant of lymphangio matosis with predominant or exclusive involvement of the soft tissues of the limb/limb girdle are described. The six patients were male and presented with slowly progressive swelling of the involved limb. The a ge of onset was at birth (three cases), 3 months (one case), 11 years (one case) and 12 years (one case). Five patients had involvement of t he lower extremity and one of the right upper extremity. Three patient s had concomitant asymptomatic bone involvement either in the affected limb (two cases) or in distant bones (one case). Only one patient had visceral involvement that was limited to the ipsilateral thorax and w as associated with chylothorax. Diagnosis was confirmed in all but one patient by lymphangiography. Treatment consisted principally of surgi cal reduction with significant clinical improvement. No patient later developed systemic involvement and the clinical course was benign. The bone lesions did not progress in any patient. Histologically, each ca se was characterised by interconnecting, dilated lymphatic spaces, lin ed by a single, attenuated layer of endothelial cells, involving the d ermis, subcutis, and occasionally, underlying fascia and skeletal musc le with characteristic and extensive ''dissection'' of collagen and su rrounding normal adnexal structures. Despite the absence of red blood cells in the vascular spaces, interstitial hemosiderin deposition was prominent in four cases. As opposed to most cases of lymphangiomatosis , which usually have extensive visceral involvement associated with a very poor prognosis, involvement in this variant is limited almost exc lusively to soft tissues of the limb and bone and is associated with g ood prognosis.