New Pattern of Sutural Synostosis Associated With TWIST Gene Mutation and Saethre-Chotzen Syndrome: Peace Sign Synostosis

Extended experience in parieto-occipital expansion surgery by meander technique-clinical and radiological evaluation

INTRODUCTION

Brachycephaly and anterior and posterior plagiocephaly appear as an isolated entity or manifest in syndromic conditions. In severe cases, possible treatment options currently comprise either cranioplasty or osteogenetic distraction. The aim of this paper is to retrospectively review the perioperative course of a series of children treated by posterior meander expansion technique at our institution with focus on the course of postoperative intracranial volume and eventual tonsillar descent evolution.

METHODS

Forty-two children received a posterior cranial vault remodeling by means of a posterior meander technique during a 7-year period. Hospital records were reviewed, and pre- and postoperative MRIs were analyzed for intracranial volume, cephalic and asymmetry index, and tonsillar position over time.

RESULTS

Median age at surgery was 11.5 months (range 17 days-10 years). Nineteen children had a symmetrical cranial deformity, twenty-three an asymmetrical synostosis. Half of the cohort showed a syndromic condition. Transfusions were administered in the majority (92.2%) of the cases. A significant postoperative increase of intracranial volume was present from 1188.9 ± 370.4 cm³ to 1324.8 ± 352.9 cm³ (p < 0.001). The asymmetry index showed a significant improvement postoperatively: 0.86 ± 0.06 versus 0.91 ± 0.05 (p < 0.001), while the cephalic index showed a non-statistical change (0.91 ± 0.11 versus 0.88 ± 0.08). Tonsillar herniation, bilateral or homolateral, showed no significant changes at early control, while a nonsignificant amelioration of tonsillar descent was seen among children older than 12 months at late imaging follow-up.

CONCLUSION

Among the osteoplastic techniques, the posterior meander technique offers several advantages, such as early mobilization of the child, less bony defects, absence of implants, and a small complication rate. However, further comparative studies among different surgical techniques are needed.

Saethre-Chotzen Syndrome: A Report of 7 Patients and Review of the Literature

INTRODUCTION

Saethre-Chotzen syndrome is a genetic condition characterized by craniofacial and limb anomalies, with craniosynostosis (mainly coronal) being the most frequent craniofacial finding. Cranial and facial deformities can be extremely variable requiring individualization of treatment strategies. We present our case series to highlight clinical findings, treatment philosophy, and challenges facing Saethre-Chotzen patients.

METHODS

A retrospective review was performed on records of patients given a diagnosis of Saethre-Chotzen syndrome at the University of California Los Angeles (UCLA) Craniofacial Clinic (n = 7) between 1980 and 2010. Patients with complete records were included in this study, and review of demographic data, clinical findings, surgical interventions and postoperative follow-up, and stability were performed.

RESULTS

Seven patients (1 male and 6 female) were included in this study. The average age at which the patients were first seen was 6.5 years. Suture involvement was bicoronal (n = 6) and unicoronal (n = 1). There was 1 patient having superimposed metopic synostosis, and there was another patient having Kleeblattschädel deformity. Previous procedures performed for patients before establishing care at UCLA were strip craniectomy (n = 2) and fronto-orbital advancement (n = 2). All patients (n = 7) had fronto-orbital advancements at UCLA. Other skeletal operations included the following: redo forehead advancement and contouring (n = 3), monobloc advancement (n = 1), and LeFort III distraction (n = 1). Five patients reached skeletal maturity, and 2 patients received LeFort I advancement for class III malocclusion, one of which also required a bilateral sagittal split osteotomy of the mandible.

CONCLUSION

Clinical presentation and severity of deformity in Saethre-Chotzen syndrome are variable. Our current report reviews our treatment strategies and illustrates the predominance of cranial and upper face deformities and frequent need for redo surgeries to address forehead asymmetry in this group of syndromic craniosynostosis patients.

Genetic advances in craniosynostosis

Craniosynostosis, the premature ossification of one or more skull sutures, is a clinically and genetically heterogeneous congenital anomaly affecting approximately one in 2,500 live births. In most cases, it occurs as an isolated congenital anomaly, that is, nonsyndromic craniosynostosis (NCS), the genetic, and environmental causes of which remain largely unknown. Recent data suggest that, at least some of the midline NCS cases may be explained by two loci inheritance. In approximately 25-30% of patients, craniosynostosis presents as a feature of a genetic syndrome due to chromosomal defects or mutations in genes within interconnected signaling pathways. The aim of this review is to provide a detailed and comprehensive update on the genetic and environmental factors associated with NCS, integrating the scientific findings achieved during the last decade. Focus on the neurodevelopmental, imaging, and treatment aspects of NCS is also provided.

A rare case of acrocephaly: Saethre-Chotzen syndrome or Crouzon?

Acrocephaly is a common neonatal craniofacial malformation. Saethre-Chotzen syndrome (SCS) is one of the acrocephaly related syndromes less frequently described in the literature. A female newborn term was admitted to our Neonatal Unit to study craniofacial dysmorphia without family history of interest. Pregnancy, childbirth and the neonatal period were uneventful. She had exotropia, short anterior-posterior cranial diameter, flat occiput and wide normotensive anterior fontanelle (beginning at the nose root, continuing through the sagittal suture with the posterior fontanelle) without syndactyly. The scanner imaging confirmed an acrocephaly with fusion of bilateral coronal sutures. We initially suspected a cranyosinostosis due to a Crouzon syndrome or SCS. After differential diagnosis and genetic study the patient was diagnosed as having SCS due to a de novo TWIST1 gene mutation. The craniofacial dysmorphias were corrected early by neurosurgical with good results. This case shows a new example of the phenotypic and genotypic variability of these TWIST1 gene mutations.

Novel Molecular Markers for Breast Cancer

The use of molecular biomarkers assures that breast cancer (BC) patients receive optimal treatment. Established biomarkers, such as estrogen receptor, progesterone receptor, HER2, and Ki67, have been playing significant roles in the subcategorization of BC to predict the prognosis and decide the specific therapy to each patient. Antihormonal therapy using 4-hydroxytamoxifen or aromatase inhibitors have been employed in patients whose tumor cells express hormone receptors, while monoclonal antibody to HER2 has been administered to HER2-positive BCs. Although new therapeutic agents have been developed in the past few decades, many patients still die of the disease due to relapse; thus, novel molecular markers that predict therapeutic failure and those that can be targets for specific therapy are expected. We have chosen four of such molecules by reviewing recent publications, which are cyclin E, B-Myb, Twist, and DMP1β. The oncogenicity of these molecules has been demonstrated in vivo and/or in vitro through studies using transgenic mice or siRNAs, and their expressions have been shown to be associated with shortened overall or disease-free survival of BC patients. The former three molecules have been shown to accelerate epithelial-mesenchymal transition that is often associated with cancer stem cell-ness and metastasis; all these four can be novel therapeutic targets as well. Thus, large prospective studies employing immunohistochemistry will be needed to establish the predictive values of these molecules in patients with BC.