An unusual congenital facial anomaly: erectile proboscis-like structure.

We report a 3-week-old male infant with an unusual congenital facial anomaly, which is characterized by a proboscis-like erectile structure arising from the right malar region. Although it is a tubular structure resembling the proboscis lateralis, this case was more likely to be a new congenital anomaly because of the following reasons: (1) in contrast with the proboscis lateralis, which originates from the medial portion of the orbital roof, the structure was located at the right malar region in our case; (2) although it was soft and freely dangling on the face, this proboscis-like structure was strongly erectile, with contraction of the orbicularis oculi muscle when the infant cried; (3) histopathological examination revealed that the structure was composed by normal fibroadipose tissue and striated muscle covered with a healthy skin and subcutaneous tissue. In contrast with histopathological characteristics of a proboscis lateralis, there was neither osteocartilaginous tissue nor mucosa in the structure. Although it is a typical finding for a proboscis lateralis, no lumen was found in the presented anomaly. Because of these unique characteristics, which remarkably differ from previously reported facial anomalies, we thought this case worth reporting. A literature review revealed that no similar case has been reported in the literature.