Aims:Tuberous sclerosis complex is a genetic disorder characterized by mutations in Tuberous Sclerosis Complex 1 (* 605284) or Tuberous Sclerosis Complex 2 (* 191092) genes. PALB2 (* 610355) gene has long been known to be associated with increased breast and pancreatic cancer risk. Its association with risk of stomach and lung cancers has also been established recently. In this case report, it is aimed to present a case of a 24-year-old female patient, who has been diagnosed with both novel mosaic Tuberous Sclerosis Complex 2 pathogenic variation and pathogenic PALB2 variation at the same time. Case Report:A 24-year-old female patient was admitted to Trakya University Genetic Diseases Center with suspected tuberous sclerosis complex. Her primary complaints were a continuous headache and fatigue. She had no history of convulsion and seizure. There were bilateral facial angiofibromas around her nose. When genomic DNA was isolated, both novel mosaic Tuberous Sclerosis Complex 2 pathogenic variation and pathogenic PALB2 variation were observed.Conclusion: This case report shows that in cancer predisposing syndromes, Next-generation sequencing is a powerful technique to portrait a detailed genetic profile of patient, investigating for any mosaicism or other risk alleles.