Malignant intracranial germinoma in Smith-Lemli-Opitz syndrome: cholesterol homeostasis possibly connecting morphogenesis and cancer development

Spontaneously regressing brain lesions in Smith-Lemli-Opitz syndrome

Smith-Lemli-Opitz syndrome (SLOS) is a metabolic disorder caused by an inborn error of cholesterol synthesis that affects the development of many organ systems. Malformations in the central nervous system typically involve midline structures and reflect abnormal growth and differentiation of neurons and supporting cells. Despite these defects in central nervous system development, brain tumor formation has only rarely been reported in association with SLOS. We present three individuals with SLOS and lesions in the basal ganglia or brainstem detected by MRI that were concerning for tumor formation. However, the individuals' clinical and neurological course remained stable, and the lesions regressed after several years. These lesions have similarities to spongiotic changes observed in individuals with neurofibromatosis type 1 (NF1). Notably, impaired activity of small GTPases is present in both SLOS and NF1, perhaps giving mechanistic insight into the formation of these lesions.

A practical guide for evaluating gonadal germ cell tumor predisposition in differences of sex development

Differences of Sex Development (DSD) includes a wide spectrum of etiologies and phenotypes. A subset of individuals with DSDs are predisposed to gonadal germ cell tumor (GCT). In this setting, GCT risk varies widely, depending on the DSD molecular etiology and penetrance. Prognostication based on molecular diagnosis remains challenging, as natural history data specific to recently identified molecular causes of DSD is lacking. In this review, we provide a framework for the clinical geneticist to consider GCT tumor risk in the patient with DSD. We discuss germ cell development and etiology of GCT growth, along with parameters to consider when recommending prophylactic gonadectomy including fertility, hormonal output, and malignant GTC treatment outcomes. Shortly after the 2006 reorganization of DSD nomenclature, literature reviews of natural history publications stratified GCT risk by a chromosomal, pathological, and hormonal taxonomy. Our 2017 literature review reveals a larger body of publications. However, the broad DSD GCT risk stratification within the 2006 taxonomy remains stable. We discuss precise GCT risk assessment for specific diagnoses, including androgen insensitivity, Smith-Lemli-Opitz, and 46,XY with MAP3K1 mutations and gonadal dysgenesis, as examples. We also examine the GCT risk in non-DSD syndromes, in addition to the cancer risks in DSD patients with dimorphic gonads and genitalia. This review is intended to provide a nuanced assessment of relative germ cell tumor risk in the DSD patient, including modern precise molecular diagnosis, for use by the clinical geneticist.

Intracranial undifferentiated malign neuroglial tumor in Smith-Lemli-Opitz syndrome: A theory of a possible predisposing factor for primary brain tumors via a case report

BACKGROUND

Smith-Lemli-Opitz Syndrome (SLOS) is a rare hereditary autosomal recessive disorder with broken cholesterol synthesis causing by 7-dehydrocholesterol reductase deficiency. Although the clinical features and pathogenesis is well-defined, it is unknown whether there is a relationship between SLOS and neoplastic processes, especially brain neoplasms.

PURPOSE

We aimed to attract the attentions to any possibility of relation between SLOS and intracranial tumor development via a pediatric case with both intracranial high-grade neuroglial tumor and SLOS, and thus to contribute an additional data to the literature on togetherness of these two clinical conditions.

METHOD

In our clinic, we experienced an interesting case of a 10-year-old child with both SLOS and huge brain tumor as rarely seen. Here, we reviewed the features and pathophysiology of SLOS and brain tumors via this case.

RESULTS

The patient was operated in our clinic, after, his brain tumor had been diagnosed, and his histopathology was resulted in undifferentiated malignant neuroglial WHO grade 4 tumor.

CONCLUSION

According to current literature, our case is the first report on coexisting of SLOS and intracranial undifferentiated malignant neuroglial tumor. Common pathways like impaired sonic hedgehog (Shh) signaling pathway may be considered for pathogenesis of a probable link between SLOS and brain tumors in further studies.