A small percentage of patients with portwine stains experience cobblestone formation and/or soft tissue hypertrophy. Cobblestones usually develop in the 4th or 5th decades of life and are nodules/small bumps that appear on the surface of the portwine stain and over the course of several years, increase in size. Cobblestones can bleed, become painful and quite large. Soft tissue hypertrophy refers to a thickening of the tissues involved in the portwine stain. The tissues involved continue to grow. Growth takes place in all of the tissue layers and this usually commences and is noticeable at a much younger age.
Both of these conditions can be surgically corrected. Once again, surgery is not ‘curative’ but the results are usually long term.