Tuberous sclerosis complex (TSC) is a genetic disease characterized by the presence of hamartomatous lesions in multiple organs and cortical tubers in the brain. The majority of patients with TSC have epilepsy, although the mechanisms underlying epileptogenesis remain unknown. Tubers are traditionally thought to be stable lesions that result from abnormal corticogenesis in early fetal development. Recently, cystlike tubers have been identified in nearly half of patients with TSC, although the spectrum and natural history of these lesions remains unknown. Herein we report eight children with a high burden of cystlike tubers and present detailed clinical information on two children with documented progression. We also report neuropathologic findings of one of the cystlike cortical tubers resected in epilepsy surgery. These cases support the notion that cystlike tubers in TSC are not static lesions and can exhibit evolving characteristics over time. Further work evaluating how these lesions relate to epileptogenesis needs to be done.