Stringent delineation of Pallister-Hall syndrome in two long surviving patients: importance of radiological anomalies of the hands.

We report two unrelated, long surviving patients (2 and 17 years) with syndromal hypothalamic hamartoblastoma. Both showed mild facial dysmorphism (downward slanted palpebral fissures, ptosis, microretrognathia), cleft epiglottis, and developmental delay. The younger child had stenosis of the pulmonary arteries, complex urogenital malformations, and anal atresia. In the oldest patient, the hamartoma caused precocious puberty of the central type, combined with complete hGH deficiency. Both patients showed bony anomalies of the extremities: variable proximal synostosis between central (2nd to 4th) metacarpals or intercalary polydactyly with generalised brachydactyly, severe brachytelephalangism, syndactyly, and nail hypoplasia. Together with the absence of anomalies of cholesterol metabolism, a combination of oral frenula, laryngeal malformations, digestive abnormalities, intercalary polysyndactyly, generalised brachytelephalangism, and nail hypoplasia should allow the delineation of Pallister-Hall syndrome, even when a CNS tumour is absent. The radiological abnormalities are helpful in differentiating Pallister-Hall syndrome from the other syndromes in which hypothalamic hamartoblastoma is observed. This is of major importance for genetic counselling, since Pallister-Hall syndrome may be a dominantly inherited disorder, thus contrasting with most of the other disorders with the CAVE phenotype, which are recessively inherited.