The 14 tumors reported in Rubinstein-Taybi syndrome since 1989, when added to the 22 previously reported, are beginning to show a pattern of neural and developmental tumors, especially of the head, which is malformed in the syndrome. Among the neoplasms were 12 of the nervous system: 2 each of oligodendroglioma, medulloblastoma, neuroblastoma, and benign meningioma, a pheochromocytoma, and 3 other benign tumors; 2 of nasopharyngeal rhabdomyosarcoma; and 1 each of leiomyosarcoma, seminoma, and embryonal carcinoma. Among the other benign tumors were an odontoma, a choristoma, a dermoid cyst, and 2 pilomatrixomas.

This presentation records the early history of the description of the broad thumb-hallux syndrome and attempts to update the current state of knowledge about this syndrome.Information was collected and reviewed on 571 individuals from the world literature, from communications with colleagues and families of affected individuals, and from personal observation. The diagnosis was established in most cases by confirming the concurrence of the constellation of major diagnostic criteria, including broad short terminal phalanges of the thumbs and halluces, with or without angulation deformity; characteristic facial appearance with beaked or straight nose, antimongoloid slant of palpebral fissures, apparent or clinical hypertelorism and grimacing smile; stature and head circumference (OFC) below 50th centile; mental, motor, social, and language retardation; stiff awkward gait; and incomplete or delayed descent of testes in males. Information on associated clinical factors, familial occurrence, and cytogenetic findings is presented

Rubinstein-Taybi syndrome (RTS) is a rare multiple congenital anomaly/intellectual impairment syndrome. Loss of function in CREBBP or EP300 genes has been found in about 50% of patients with RTS. Genotype-phenotype correlations were investigated in 93 patients meeting diagnostic criteria for RTS during 2 international RTS family conferences. Mutation analysis of CREBBP was performed on all 31 coding exons and exon-intron junctions; a subset of patients had FISH analysis for large deletions. A total of 64 different variations were observed in the DNA sequence, and determined to be definitive mutations in 52 patients (56%). Mutations detected included: 10 missense mutations; 36 truncating or splice-site mutations; and 6 large deletions detectable by FISH. Fourteen patients had synonymous changes of unknown significance. The majority of mutations affected the HAT domain of CREBBP or predicted termination of the protein before the HAT region. Extensive phenotypic data were collected on each patient and analyzed to determine correlations with mutation types, that is, truncating, large deletions, single amino acid substitutions, or no CREBBP mutation. All four groups displayed the characteristic facial and thumb dysmorphology. Growth retardation in height and weight was seen more frequently in patients with no CREBBP mutation; seizure disorder was more frequent in those with CREBBP mutations. Degree of mental retardation was similar in all groups, although there was a trend toward lower IQ and autistic features in patients with large deletions. Similarity in phenotype between the groups implies that the several genes involved in causing RTS likely have effects through the same pathway.

Children and adults with Rubinstein-Taybi Syndrome have specific medical conditions that occur with greater frequency than the general population. Based on the available information from the literature and clinical experience, recommendations for specific surveillance and interventions are made to guide those clinicians caring for individuals with Rubinstein-Taybi Syndrome. This is a first attempt at medical guidelines for individuals with RTS in the United States. On-going research is needed in many areas to guide decisions in medical care and allow for refinement of these medical guidelines.