Recurrent Mandibular Giant Cell Lesion in Neurofibromatosis Type 1: Second Hit Mutation on the NF1 Gene in the Osseous Lesion

BACKGROUND/AIM

In the autosomal dominant hereditary disease neurofibromatosis type 1 (NF1), lesions of the jaw develop in isolated cases, which are diagnosed as central giant cell granuloma (CGCG). This study aimed to clarify the genetic basis of a bone lesion in a syndromic patient.

CASE REPORT

The NF1 patient had developed a CGCG that recurred after local excision. Blood and tumor tissue were studied for NF1 mutations using advanced molecular genetic methods. Examinations of blood and tumor tissue provided evidence of the constitutive mutation in both samples. A further mutation was detected in the tumor, which was interpreted as a somatic mutation. The detection of somatic mutation in the tissue was successful both on native and routinely fixed material.

CONCLUSION

The study supports current assessments of CGCG as a benign neoplasm. In NF1 patients, the phenotype seems to imply bi-allelic loss of the NF1 gene. The detection of both mutations in routinely fixed tissue allows studies of archived tissue samples with this diagnosis.

Oral HRAS Mutation in Orofacial Nevus Sebaceous Syndrome (Schimmelpenning-Feuerstein-Mims-Syndrome): A Case Report With a Literature Survey

BACKGROUND/AIM

The aim of this study was to present the long-term course of a patient with nevus sebaceous syndrome (NSS). Recent genetic studies place the syndrome in the emerging group of so-called RASopathies. The focus of the report is on surgical treatment and morphological and genetic findings of the face and oral cavity.

CASE REPORT

A female patient was treated for congenital alterations of facial skin and oral mucosa. The oral lesions were removed repeatedly. Eruption of teeth on the lesion sites was made easier by the measures taken. However, after repeated ablation of the affected gingiva, the periodontal papillomatous epithelium re-differentiated into the same reddish, conspicuous, hyperplastic epithelium. The teeth in the affected region showed noticeable changes in position, surface, and shape. A HRAS mutation was detected only in the regions of altered oral epithelia and not in adjacent soft tissues.

CONCLUSION

Reports on NSS rarely address oral manifestations. The recorded alterations of oral soft and hard tissues in NSS indicate a topographical relationship between the development of oral mucosa and teeth as well as the long-lasting impact of a sporadic mutation on organ development at this site.

Ablation Precision and Thermal Effects of a Picosecond Infrared Laser (PIRL) on Roots of Human Teeth: A Pilot Study Ex Vivo

BACKGROUND/AIM

Picosecond infrared laser (PIRL) was investigated regarding its possible therapeutic application in cutting dental roots.

MATERIALS AND METHODS

Extracted human teeth were processed in the root area by laser ablations followed by histological evaluation. Dentin adjacent to the cutting surface was evaluated morphometrically.

RESULTS

PIRL produced clearly defined cutting boundaries in dental roots. At the bottom of the cavity, the ablation surface became slightly concave. Heat development in this scantly hydrated tissue was considerable. We attributed the excess heating effects to heat accumulation due to multiple pulse overlap across a limited scan range imposed by tooth geometries.

CONCLUSION

Defined areas of the tooth root may be treated using the PIRL. For clinical translation, it would be necessary to improve beam delivery to facilitate beam steering for the intended oral application (e.g. by using a fiber) and identify optimal repetition rates/scan speeds combined with cooling techniques to minimize accumulated heat within ablation cavities.

Lingual Mandibular Bone Depression

BACKGROUND/AIM

In the area of the jaw angle, osteolytic lesions can occur, the differential diagnosis of which can be difficult and require very different therapeutic measures. One of these lesions is lingual mandibular bone depression (LMBD). The aim of this study was to present the characteristics of the lesion in a group of LMBD patients and to differentiate it from other lesions.

PATIENTS AND METHODS

Radiological images of 21 patients with LMBD were examined.

RESULTS

The majority of LMBDs were located in the jaw angle. On cross-sectional images, the lesion could be distinguished from salivary tissue (n=2). One case of LMBD had an impact on the course of the fracture line in the mandibular trauma.

CONCLUSION

LMBD is a developmental disorder of the mandible and only rarely of pathological importance. Imaging the lesion with cross-sectional images is preferable to using plain X-ray projections. In some cases, surgical exploration is essential for diagnosis.

Neurofibromatosis Type 1 With Cherubism-like Phenotype, Multiple Osteolytic Bone Lesions of Lower Extremities, and Alagille-syndrome: Case Report With Literature Survey

BACKGROUND/AIM

Neurofibromatosis type 1 (NF) is an autosomal dominant hereditary disease. The cardinal clinical findings include characteristic skeletal alterations. Difficulties in diagnosis and therapy can arise if an individual has further illnesses.

CASE REPORT

This is a case report of a 16-year-old patient affected by NF1. She also suffered from Alagille syndrome and the consequences of fetal alcohol exposure. The patient's facial phenotype showed findings that could be assigned to one or more of the known diseases. The patient was referred for treating a cherubism-like recurrent central giant cell granuloma (CGCG) of the jaw. The patient developed bilateral, multilocular non-ossifying fibromas (NOF) of the long bones of the lower extremity. Treatment of the skeletal lesions consisted of local curettage. While NOF regressed after surgery, the CGCG of the jaw remained largely unchanged. Extensive genetic tests confirmed a previously unknown germline mutation in the JAG1 gene, the germline mutation of the NF1 gene, and the somatic mutation in the NF1 gene in the diffuse plexiform neurofibroma, but not in the CGCG.

CONCLUSION

Assigning facial findings to a defined syndrome is ambiguous in many cases and especially difficult in patients who have multiple diseases that can affect the facial phenotype. Surgical therapy should be adapted to the individual findings.

KRAS Mutation in an Implant-associated Peripheral Giant Cell Granuloma of the Jaw: Implications of Genetic Analysis of the Lesion for Treatment Concept and Surveillance

The aim of this case report was to detail diagnosis and therapy in a case of implant-associated peripheral giant cell granuloma (IA-PGCG) of the jaw. Case Report: The 41-year-old female attended the outpatient clinic for treatment of recurrent mandibular IA-PGCG. The lesion was excised and the defect was closed with a connective tissue graft of the palate. Healing of oral defects was uneventful, and no local recurrence has occurred during a follow-up of 7 months. Genetic examination of the lesion identified a somatic mutation in KRAS. Conclusion: The lesions are assessed as reactive-inflammatory changes in the mucous membrane of the oral cavity. The cause of the lesion is unknown. KRAS mutations are commonly found in various cancer tissues, but also in germline and mosaic RASopathies. Recently, KRAS mutations have been identified in several IA-PGCG. The clinical course of a frequently locally recurring lesion gives rise to the assumption that lesions of this type show characteristics known in benign neoplasms.

Preauricular Swelling Mimicking a Tumour: Dissolution of Mandibular Capitulum Following Trauma in a 15-Year Old Child

AIM

The report is about diagnosis, therapy, and follow-up of a 15-year old boy, who experienced facial swelling and impaired mouth opening after a sport accident.

CASE REPORT

Diagnosis of mandibular damage was delayed due to inadequate clinical investigation and radiography after trauma and only became clear after a parotid swelling occurred sometime later resulting from the dissolution of the upper part of the articular process. Follow-up control over a period of three years showed a partial restoration of the articular process but some inhibition of mouth opening combined with slight deviation of the mandible to the affected side remained over the years.

CONCLUSION

This report reminds us that parotid swelling can be the result of mandibular trauma without a recent history of physical injury to this region. Therefore, the basic standards of radiologic diagnosis should be maintained and the limited restoring capacity of the condylar process in adolescence should be acknowledged.

Symptomatic Intraosseous Vascular Malformation of Infraorbital Rim: A Case Report With Literature Survey

BACKGROUND/AIM

Intraosseous orbital hemangiomas or vascular malformations (VM) are rare. This report is intended to complement the experience of diagnosing and treating a rare vascular lesion at this site. Special attention is paid to three-dimensional imaging and the morphological distinction between the two entities in this location.

CASE REPORT

A 54-year-old female was examined and surgically treated for an exophytic firm mass of the infraorbital, which had become palpable as a hard mass due to growth in size. At first, a bone tumor, for example, an osteoma, was suspected. Intraoperatively, an osseous expansion with distinct fenestrations of the newly grown bone's surface, was detected. The lesion was firmly attaching to the orbital rim. The densely vascularized tumor was well defined to the soft tissues but had grown in continuity from the orbital floor and rim. Vascularized cavities caused the tumor to have a slightly reddish color. The histological examination confirmed the suspicion of the lesion's vascular origin. The lesion's immunohistochemical expression profile approved the final diagnosis of intraosseous VM.

CONCLUSION

The symptoms of intraosseous vascular lesions of the orbit are determined by location and size. Modern imaging techniques facilitate the estimation of tumor-like expansion of lesions. However, the imaging characteristics of intraosseous vascular lesions are very variable. The symptoms of the patient presented herein show that growth phases of a vascular orbital malformation can occur in later stages of life and are initially indistinguishable from a neoplasm. In individual cases, patient care necessitates advanced diagnostic measures to establish the diagnosis and determine surgical therapy.

Mosaic Neurofibromatosis Type 1 With Multiple Cutaneous Diffuse and Plexiform Neurofibromas of the Lower Leg

BACKGROUND

Neurofibromatosis type 1 (NF1) is an autosomal dominant hereditary disease with complete penetrance and a very variable phenotype. Recent research has shown that postzygotic NF1 gene mutations occur to a far greater extent than previously thought. The phenotype of affected individuals reflects the time of somatic mutation and the phenotype is correspondingly diverse. This report describes histological and genetic findings in a case of mosaic NF1, the clinical control of which documents almost stationary skin findings over a period of 9 years.

CASE REPORT

The 55-year-old female first presented for advice on a strip of nodular skin tumours of the calf skin. She had no hallmarks of NF1. It was only 9 years later that she had the skin tumours removed, all of which were partially diffuse and partially plexiform neurofibroma. The genetic examination showed an atypical large deletion of the NF1 gene in the skin tumours, but not in overlying skin or blood.

CONCLUSION

Segmental NF1 is a distinct type of mosaic/somatic NF1 mutation. The phenotype of diffuse and plexiform skin neurofibromas can resemble cutaneous neurofibroma. Surgical therapy for segmental neurofibromatosis does not differ from the concepts for treating nerve sheath tumours in NF1 patients with a germline NF1 mutation.

Vestiges of Ossified Spheno-occipital Suture in an Elderly Patient With Down Syndrome and Lateral Skull Base Fracture

BACKGROUND/AIM

Down syndrome (DS) patients often show characteristic changes in the skull, e.g. short cranial base. The synchondroses of the skull base have a significant influence on the shape of the skull. The sphenooccipital synchondrosis (SOS) is the last of the basal synchondroses to ossify. This report is about residual ossification of SOS in an elderly patient with DS.

CASE REPORT

The 65-year-old DS patient was polytraumatized by a fall. In the course of treatment, a purulent otitis externa on the right side was diagnosed, which had developed as a result of the fracture of the fossa glenoidalis. Computed tomograms of the skull base showed the fracture of the mandibular condyle, glenoid fossa and vestiges of SOS.

CONCLUSION

The coincidental finding of vestiges of SOS in an elderly patient with DS raises the question of whether cross-sectional skull base images can show differences in the ossification of SOS between DS patients and a normal population.

Symptomatic Mandibular Fibrous Dysplasia With Concurrent Triple X- and Premutation Stage Fragile-X-Syndrome: Case Report With Short Literature Survey

BACKGROUND

Certain constitutive chromosomal abnormalities of the human X chromosome are relatively common in conspicuous neuropsychiatric findings. Although tumors or tumor-like lesions are occasionally reported in diseases of the X chromosome, they are numerically negligible, for example, in aneuploidy such as the triple X syndrome (TXS).

CASE REPORT

A 16-year-old female patient with a known TXS and premutation stage of fragile X syndrome was referred by her dentist for diagnosis and treatment of unilateral cheek swelling. The examination of the psychologically conspicuous patient revealed a unilateral mandibular tumor with dysesthesia of the mental nerve. Surgical removal of soft, crumbly spongiosa over the nerve canal resulted in sufficient pressure release of the constricted nerve and restoration of epicritic sensitivity. Imaging findings and histological and molecular genetic examination revealed monostotic craniofacial fibrous dysplasia.

CONCLUSION

Although the data in the literature do not give reason to suppose an accumulation of neoplasms in TXS, a numb chin syndrome should be a reason for detailed diagnostics. Careful diagnosis allows for customized therapy. This is the first report on the coincidence of TXS, fragile X syndrome, and fibrous dysplasia in a single individual.