Bannayan-Riley-Ruvalcaba syndrome is an autosomal dominant disorder causing multiple malformations, mainly macrocephaly, multiple lipomas, intestinal hamartomatous polyps, vascular malformations, and abnormal pigmentation of the penis. Approximately half the patients affected by this syndrome develop hypotonia, and moderate to severe mental retardation. The clinical picture is similar to that of Cowden disease, a predisposing syndrome to cancer, especially thyroid and breast cancer. The risk of tumors degenerating into neoplasms in patients affected by Bannayan-Riley-Ruvalcaba syndrome has not been clearly established. The disorder is due to mutations in the PTEN tumor suppressing gene coding for a tyrosine phosphatase on chromosome 10q. Mutations tend to occur in exons 6 or 7 of the gene.
Last update: January 2004