Cowden Syndrome and the PTEN Hamartoma Tumor Syndrome: Systematic Review and Revised Diagnostic Criteria

BackgroundPTEN hamartoma tumor syndrome (PHTS) refers to a spectrum of disorders caused by mutations in the phosphatase and tensin homolog ( PTEN) gene. Diagnostic criteria for Cowden syndrome, the principal PTEN -related disorder, were first established in 1996 before the identification of the PTEN gene and the ability to molecularly confirm a clinical diagnosis. These consortium criteria were based on clinical experience and case reports in the existing literature, with their inherent selection biases. Although it was initially reported that approximately 80% of patients with Cowden syndrome had an identifiable germline PTEN mutation, more recent work has shown these diagnostic criteria to be far less specific. In addition, increasing evidence has documented the association of a broader spectrum of clinical features with PTEN mutations. Our goal was to develop revised, evidence-based diagnostic criteria and to include features of the broader spectrum of PTEN -related clinical syndromes.