Vaginal yolk sac tumor causing infantile hydrometra: use of multidetector-row computed tomography.

Background: A case of vaginal endodermal sinus (yolk sac) tumor resulting in hydrometra in a 9-month-old female infant is reported.

Case: The patient presented with an intermittent bloody discharge on her diapers and a lower abdominal mass on palpation. Multidetector-row computed tomography showed an irregular, dense soft-tissue mass with heterogeneous enhancement within the vagina, obstructing it. On reformatted computed tomography images, there was upstream dilatation of the cervical and uterine cavities, with fluid attenuation contents called hydrometra, resulting from the vaginal obstruction. The histopathological features of the vaginal mass were identical to those of the endodermal sinus tumor (yolk sac tumor). The patient was treated exclusively by means of chemotherapy.

Conclusion: Examination of the alpha-fetoprotein levels was useful in the diagnosis of the patient and in assessing the patient's response to treatment by chemotherapy.