Tuberous sclerosis complex is a systemic disorder involving multiple organs, including brain, skin, heart, lungs, and kidneys; only skeletal muscle, peripheral nerves, and craniospinal nerve roots are not involved. Consequently, the differential diagnosis of each presenting symptom or constellation of symptoms is extensive. This necessitates that tuberous sclerosis complex be considered in the differential diagnosis of many presenting problems, including seizures, developmental delay or mental retardation, autism, ADHD, hemiplegia, uremia, intra-abdominal hemorrhage, and respiratory failure. Similarly, tuberous sclerosis complex should be considered as the underlying cause of a variety of tumors that may occur in different organ systems. However, tumors that occur in tuberous sclerosis complex are typically rare in the general population and infrequently progress to malignancy. Only renal cell carcinoma occurs earlier and with greater frequency in tuberous sclerosis complex (Bjornsson et al 1996; Cook et al 1996).