Rhabdomyomas and tuberous sclerosis complex: our experience in 33 cases

Unusual Outcome of a Right Ventricular Rhabdomyoma in an Infant

Rhabdomyomas are the most common benign cardiac tumors. They may often be associated with tuberous sclerosis. In many cases, cardiac rhabdomyomas undergo spontaneous regression. Here, we report the unusual case of an infant with a large nonobstructive right ventricular rhabdomyoma at birth and at four months of age, which subsequently caused severe right ventricle outflow tract obstruction at six months of age, prompting surgery to remove the tumor. Close monitoring should be done in infants with large nonobstructive cardiac rhabdomyomas.

Mammalian Target of Rapamycin Inhibitors and Life-Threatening Conditions in Tuberous Sclerosis Complex

Tuberous sclerosis complex (TSC) is a multisystem disease associated with an overall reduction in life expectancy due to the possible occurrence of different life-threatening conditions. Subjects affected by TSC are, in fact, at risk of hydrocephalus secondary to the growth of subependymal giant cell astrocytomas, or of sudden unexpected death in epilepsy. Other nonneurological life-threatening conditions include abdominal bleeding owing to renal angiomyolipomas rupture, renal insufficiency due to progressive parenchymal destruction by multiple cysts, pulmonary complications due to lymphangioleiomyomatosis, and cardiac failure or arrhythmias secondary to rhabdomyomas. In the last decades, there has been a great progress in understanding the pathophysiology of TSC-related manifestations, which are mainly linked to the hyperactivation of the so-called mammalian target of rapamycin (mTOR) pathway, as a consequence of the mutation in 1 of the 2 genes TSC1 or TSC2. This led to the development of new treatment strategies for this disease. In fact, it is now available as a biologically targeted therapy with everolimus, a selective mTOR inhibitor, which has been licensed in Europe and USA for the treatment of subependymal giant cell astrocytomas and angiomyolipomas in subjects with TSC. This drug also proved to benefit other TSC-related manifestations, including pulmonary lymphangioleiomyomatosis, cardiac rhabdomyomas, and presumably epileptic seizures. mTOR inhibitors are thus proving to be a systemic therapy able to simultaneously address different and potentially life-threatening complications, giving the hope of improving life expectation in individuals with TSC.

[Radiological evaluation of congenital tumors]

In this article, we consider tumors that are diagnosed during pregnancy or in the first three months of life. This is a heterogeneous group of neoplasms with special biological and epidemiological characteristics that differentiate them from tumors arising in children or adults. In the last two decades, the prenatal detection of congenital tumors has increased due to the generalized use of prenatal sonographic screening. Advances in imaging techniques, especially in fetal magnetic resonance imaging, have enabled improvements in the diagnosis, follow-up, clinical management, and perinatal treatment of these tumors. This image-based review of the most common congenital tumors describes their histologic types, locations, and characteristics on the different imaging techniques used.

Myocardial Fatty Foci in Adult Patients with Tuberous Sclerosis Complex: Association with Gene Mutation and Multiorgan Involvement

PURPOSE

To estimate the association between myocardial fatty foci (MFF) on chest computed tomographic (CT) images and type of gene mutation or multiorgan involvement in patients with tuberous sclerosis complex (TSC).

MATERIALS AND METHODS

This retrospective case-control study was approved by the ethics committee, which waived the need for patient consent. Forty-eight patients with definite TSC (41 women; mean age, 35 years ± 11 [standard deviation]) and 96 age- and sex-matched patients without TSC who had undergone chest CT were evaluated. Two blinded readers independently scored MFF as low-attenuation areas within the myocardium. Patient history, gene mutation, and multiorgan involvement were obtained from clinical records. Cohen κ, Mann-Whitney U, χ(2) or Fisher exact, Kruskal-Wallis, and Spearman statistics were calculated.

RESULTS

One or more MFF was detected in 50% (24 of 48) of patients with TSC; however, no MFF was detected in control patients (P < .001). MFFs were oval (62%, 15 of 24) or linear (38%, nine of 24) and involved the left ventricle in 13 patients and both ventricles in 24 patients (mostly the apical or midleft ventricle); median size was 127 mm(2). After four patients with TSC and unknown mutational status (two with MFF) were excluded, MFF was detected in 53% (10 of 19) of patients with TSC1 mutation, 65% (11 of 17) of patients with TSC2 mutation, and 12% (one of eight) of patients with TSC but without an identified mutation (P = .044). MFF presence was associated with brain (P = .011) and multiorgan (P = .008) involvement. The number of MFF per patient correlated with the degree of multiorgan involvement (P = .014). With MFF considered predictive of TSC, 50% (24of 48) sensitivity, 100% (96 of 96) specificity, 100% (24 of 24) positive predictive value, and 80% (96 of 120) negative predictive value were obtained.

CONCLUSION

MFF was highly specific for TSC. MFF presence was associated with TSC gene mutations and with brain or multiorgan involvement; their number per patient was correlated with the degree of multiorgan involvement.