Ulcers of the lower extremities, particularly in individuals older than 65, are a common cause for visits to the dermatologist, primary-care physician, or vascular surgeon. There are many different causes of leg ulcers, among which vascular causes are the most frequent. Less commonly, other pathological processes result in leg ulcers. Unfortunately some of them are malignant. Large B-cell lymphoma, leg type, is a malignant lymphoma of intermediate behavior, occurring mostly on the legs in elderly patients. Usually it presents as erythematous or bluish-red nodules or tumors, but ulcerations are not uncommon. When faced with unusual and non-healing ulcers, the physician should also have in mind rarer but more lethal causes.