Multiple, juxtasutural, cranial hyperostoses and cardiac tumor: a new hamartomatous syndrome?

We report on a Japanese girl with multiple cranial hyperostoses and a cardiac tumor, both of which manifested in early childhood. Unique juxtasutural lesions characterized the cranial findings, including a chain of almost symmetrical osseous protuberances involving the frontozygomatic and frontoparietal junctions, and discrete bony bumps on the right occipitoparietal junction and left temporo-occipital junction. These lesions histologically consisted of thickened mature bone intervened with sparse fibrous tissues, mimicking osteoma. The cardiac mass remained pathologically unknown, but was shown to have fatty elements on magnetic resonance imaging (MRI). The patient showed no evidence of gnathic hyperostoses, ophthalmological abnormalities, skin lesions, or other visceral abnormalities, which ultimately precluded known hamartomatous syndromes with craniofacial hyperostoses, such as Gardner and Proteus syndromes. Yet regional Proteus syndrome could not be completely excluded. The craniofacial deformity as a sequel of hyperostoses in our patient superficially resembled that of X-linked calvarial hyperostosis; however, the vacuolated histiocytes that characterized the hyperostotic lesions were not found in our patient. The present disorder may represent a hitherto unknown hamartomatous syndrome.