SS-32 [Perinatoloji]

Fetal cardiac rhabdomyoma associated with Tuberous Sclerosis Complex; a case report

Bilal Esat Temiz1, Umutcan Kayikci2, Murat Cagan2, Kader Karli Oguz3, Kadri Safak Gucer4, Ozgur Deren2
1Department of Obstetrics and Gynecology, Faculty of Medicine, Hacettepe University, Ankara, Turkey 2Division of Perinatology, Department of Obstetrics and Gynecology, Faculty of Medicine, Hacettepe University, Ankara, Turkey

3Department of Radiology, Faculty of Medicine, Hacettepe University, Ankara, Turkey
4Division of Pediatric Pathology, Department
of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Turkey

Introduction: Tuberous Sclerosis Complex (TSC) is an autosomal dominant disease, presenting with widely variable clinical manifestations such as seizures, mental retardation, skin lesions, cardiac rhabdomyomas and hamartomas. The prevalence of TSC varies between 1/6,000-1/60,000. Rhabdomyomas are the most common cardiac tumors. It characteristically appears in late pregnancy and commonly regress spontaneously in neonatal period. While 20-40% of single rhabdomyomas are accompanied by TSC, this rate rises up to 95% when they are multiple. In this report, we have presented a case of fetal cardiac rhabdomyoma diagnosed with TSC.

Case Presentation: A 34-year-old, primigravid woman with no significant history was referred to the Division of Perinatology, Hacettepe University due to cardiac mass. There was no consanguinity between spouses. During the detailed anatomical scan performed at 21st gestational week (gw), a 5 mm single hyperechoic mass was observed in the left ventricle (LV). The patient was admitted to our clinic at 29th gw, with a delay due to social reasons. Ultrasonography revealed multiple well-circumscribed hyperechoic masses of 10 mm in size in the LV lateral wall and interventricular septum (Figure1). The masses were not leading outflow obstruction, and cardiac function was normal. Since the masses suggested rhabdomyoma, meticulous evaluation of other fetal structures, including the brain and kidney, was performed. Fetal neurosonography revealed suspected cortical tubers. In the fetal Magnetic Resonance Imaging (MRI), subependymal nodules in the lateral ventricles and small nodular lesions in the cerebral white matter were observed. The diagnosis was thought to be TSC and the termination of pregnancy was offered. Within consent, the pregnancy was terminated at the 33rd gw and fetal autopsy was performed. Multiple cardiac rhabdomyomas and cortical tubers were observed in fetopsy (Figure 2, and 3), and a “de novo” heterozygous TSC-2 mutation was detected in the whole genome sequencing.

Discussion: Fetal cardiac tumors are rare conditions with an estimated prevalence of 0.08-0.2% and are usually diagnosed at late second trimester. Most cardiac masses in fetuses are rhabdomyomas and differential diagnosis includes teratoma, fibroma, hemangioma, and myxoma. Although the definitive diagnosis is histopathological, myocardial location without pericardial extension and multiple masses are in favor of rhabdomyoma. Rhabdomyomas tend to grow slowly in the antenatal period, and show a high rate of association with TSC, especially when multiple as in our case. Clinical manifestations of rhabdomyomas include outflow obstructions, heart failure, arrhythmia, hydrops fetalis, and stillbirth. In our case, no additional cardiac pathology was observed. Since USG is not sensitive for brain evaluation, it is recommended to perform fetal MRI as a complementary tool in suspicious cases. In our case, multiple cerebral tubers were observed in the autopsy, which was also consistent with the MRI findings. The TSC1–9q34 and TSC2–16p13.3 gene mutations have been identified in the presence of TSC. Two-third of these mutations are known to be “de novo”. In our case, a heterozygous mutation was detected in the TSC-2 gene. In conclusion, it should be kept in mind that cardiac rhabdomyomas, especially when multiple, may be the earliest manifestation of tuberous sclerosis.

Keywords: Cardiac tumor, Prenatal diagnosis, Rhabdomyoma,Tuberous Sclerosis Complex