Fetal cardiac tumors: prenatal diagnosis and outcomes

Fetal cardiac tumors are rare conditions and their incidence ranges from 0.08% to 0.2%[1]. However, this percentage during fetal life may be underestimated, given that regression commonly occurs. It should also be noted that atrial tumors may be small or, when located in the septum or ventricular cavity, often mimic an echogenic focus (golf ball sign), thus leading to difficulty in recognizing them through ultrasonographic screening[2]. Among the various histological types, the three commonest types in fetuses, newborns and children are firstly rhabdomyoma (60%) and then teratomas (25%) and fibromas (12%) [1,3,4]. These histological types are benign tumors, since malignant types are extremely rare in fetuses[4]. Rhabdomyomas are the commonest subtypes and present as homogenous hyperechogenic masses that are generally multiple, with variable sizes. They may be intramural or intracavitary, and generally occupy the interventricular septum or right ventricle, close to the moderator band, but they can be located in any cardiac chamber[4]. Rhabdomyomas are hormone-dependent tumor, which explains their well-known capacity for spontaneous regression or reduction, along with their close relationship with tuberous sclerosis[5]. Fibromas rarely present during fetal life, but are generally located in the interventricular septum or the free wall of the left ventricle. They present as large single masses and, differently from rhabdomyomas, do not regress after birth. For this reason, they may cause obstructions[4]. Fibromas require clinical follow-up at birth because they may lead to sudden death. Because they are giant masses, resection may be difficult and therefore heart