Bannayan-Riley-Ruvalcaba Syndrome in a Patient with a PTEN Mutation Identified by Chromosomal Microarray Analysis: A Case Report

Abstract

Bannayan-Riley-Ruvalcaba syndrome (BRRS) is one of the phosphatase and tensin homolog hamartoma tumor syndrome with a PTEN gene mutation. It is a rare dominant autosomal disorder characterized by cutaneous lipomas, macrocephaly, intestinal polyps, and developmental delay. Diagnosing this syndrome is important, because it may represent the pediatric phenotype of Cowden syndrome, in which there is an increased risk for malignant tumors in children. Until now, the prevalence of BRRS is unknown. Several dozen cases have been reported in the medical literature, but no case has been reported in Korea. Here we report a case of a 19-year-old girl who was diagnosed with BRRS because of macrocephaly, intellectual disability, and intestinal polyps. Her mother had similar findings and a PTEN mutation. Neither patient had mutations detected by conventional mutation-detection techniques, but a PTEN gene deletion was demonstrated by chromosomal microarray analysis.

Keywords: Bannayan-Riley-Ruvalcaba syndrome; Microarray analysis.

Fig. 1. (A) Colonoscopy showed multiple polyps on the terminal ileum. Some flat polyps without neck were noted on the rectum. (B) Gastrofibroscopy showed small multiple polyps on the stomach and duodenum.

Fig. 2. (A) Karyogram of the patient. The deletion in the long arm of chromosome 10 (arrow). Left: the patient, right: her mother. (B) Chromosomal microarray profile of chromosome 10. The X-axis represents the probe index on chromosome 10, and the Y-axis represents the signal log2 ratio of the probe. The 10q23.31 region showed a 220kb micro-deletion in Chr10. Left: the patient, right: her mother.