OBJECTIVE: To explore the clinical features and genetic etiology of two Chinese patients with Cowden syndrome (CS). METHODS: Two patients diagnosed with multiple gastrointestinal polyps by gastroenteroscopy at Henan Provincial People's Hospital in September and November 2023 were selected as the study subjects. Clinical data of the patients were collected. Whole exome sequence (WES) was carried out. Candidate variants were verified by Sanger sequencing. This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: 2018-03-01). RESULTS: The patients were diagnosed with multiple gastrointestinal polyps in addition with polypoid changes of the gallbladder. Genetic testing revealed that patient 1 has harbored a heterozygous c.738dupG (p.Leu247Valfs*6) variant of the PTEN gene, which was unreported previously. Patient 2 has harbored a heterozygous c.469G>T (p.Glu157Ter) variant of the PTEN gene, which was known to be pathogenic. None of their family members was found to harbor the above variants. Based on the guidelines from the American College of Medical Genetics and Genomics, both variants were rated as pathogenic (PVS1+PM2_Supporting+PP3+PP4). Bioinformatic analysis suggested that both variants can significantly affect the tertiary structure of the PTEN protein. CONCLUSION The heterozygous variants of the PTEN gene probably underlay the CS in both patients. Discovery of the novel variant has enriched the mutational spectrum of the PTEN gene.
Adult ; Female ; Humans ; Male ; China ; Hamartoma Syndrome, Multiple/genetics* ; Mutation ; Pedigree ; PTEN Phosphohydrolase/chemistry* ; East Asian People/genetics*

Cowden syndrome is an uncommon, autosomal dominant disease which is characterized by multiple hamartomas of the skin, mucous membrane, brain, breast, thyroid, and gastrointestinal tract. The diagnosis of Cowden syndrome implicates an increased risk of developing breast cancer. We report a case of a 22-year-old woman with Cowden syndrome that presented as breast cancer with concomitant bilateral exuberant benign masses in both breasts.
Arteriovenous Malformations/radiography ; Breast Neoplasms/*complications/*diagnosis/ultrasonography ; DNA/analysis ; DNA Mutational Analysis ; Diagnosis, Differential ; Female ; Hamartoma Syndrome, Multiple/*complications/*diagnosis/genetics/ultrasonography ; Humans ; PTEN Phosphohydrolase/genetics ; Thyroid Neoplasms/radiography ; Tomography, X-Ray Computed ; Young Adult

Child ; Codon, Nonsense ; Female ; Hamartoma Syndrome, Multiple ; diagnosis ; genetics ; Humans ; PTEN Phosphohydrolase ; genetics

Adenomatous Polyposis Coli ; genetics ; metabolism ; pathology ; Bone Morphogenetic Protein Receptors, Type I ; genetics ; metabolism ; Colorectal Neoplasms, Hereditary Nonpolyposis ; genetics ; metabolism ; pathology ; Genes, APC ; Genetic Predisposition to Disease ; Hamartoma Syndrome, Multiple ; genetics ; metabolism ; pathology ; Humans ; Microsatellite Instability ; Mutation ; PTEN Phosphohydrolase ; genetics ; metabolism ; Peutz-Jeghers Syndrome ; genetics ; metabolism ; pathology ; Protein-Serine-Threonine Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins B-raf ; genetics ; metabolism