RET protooncogene mutational analysis in multiple endocrine neoplasia syndrome type 2B: case report and review of the literature

Multiple endocrine neoplasia type 2B: Frequency of physical stigmata-Results of the GPOH-MET registry

BACKGROUND

Multiple endocrine neoplasia (MEN) 2B is characterized by early development of aggressive medullary thyroid carcinoma (MTC), visible physical stigmata, and associated symptoms. In most cases, de novo mutations are revealed. There are premonitory symptoms and stigmata that enable early diagnosis, before an inoperable MTC develops. The German Society for Paediatric Oncology and Haematology (GPOH)-Malignant Endocrine Tumours (MET) registry maintains records of children with MTC in Germany since 1997.

METHODS

Children with a diagnosis of MTC in MEN 2B recorded in the GPOH-MET study were analyzed retrospectively. Stigmata and symptoms associated with MEN 2B were examined.

RESULTS

From inception through 2017, 24 patients aged 0.2-17.3 years were included. Symptoms affecting the oral/dental (88.0%), musculoskeletal (79.2%), and gastrointestinal (70.8%) systems were recognized most frequently. Gastrointestinal and musculoskeletal symptoms preceded symptoms of MTC. Twelve patients had short stature. Regarding the prevalence of single symptoms, neuromas of the lips and the oral cavity were mentioned most frequently. Five patients died from MTC. Patients diagnosed by tumor symptoms showed more advanced disease than those with disease detected by other means. Children diagnosed via associated stigmata and symptoms or positive family history had significantly improved overall survival (OS) compared to children diagnosed via symptoms of MTC (OS 100% vs 53.3%).

CONCLUSIONS

In children with MEN 2B, oral/dental, musculoskeletal, and gastrointestinal symptoms are most common. If children are diagnosed via associated symptoms and stigmata, OS is improved. Most of the children were diagnosed with growth disturbances; this finding requires verification and ranging in other patient cohorts.

Common conditions associated with mandibular canal widening: A literature review

Purpose

The aim of this study was to review the common conditions associated with mandibular canal widening.

Materials and Methods

General search engines and specialized databases including Google Scholar, PubMed, PubMed Central, Science Direct, and Scopus were used to find relevant studies by using the following keywords: “mandibular canal,” “alveolar canal,” “inferior alveolar nerve canal,” “inferior dental canal,” “inferior mandibular canal,” “widening,” “enlargement,” “distension,” “expansion,” and “dilation.”

Results

In total, 130 articles were found, of which 80 were broadly relevant to the topic. We ultimately included 38 articles that were closely related to the topic of interest. When the data were compiled, the following 7 lesions were found to have a relationship with mandibular canal widening: non-Hodgkin lymphoma, osteosarcoma, schwannoma, neurofibroma, vascular malformation/hemangioma, multiple endocrine neoplasia syndromes, and perineural spreading or invasion.

Conclusion

When clinicians encounter a lesion associated with mandibular canal widening, they should immediately consider these entities in the differential diagnosis. Doing so will help dentists make more accurate diagnoses and develop better treatment plans based on patients' radiographs.

HPV-Related Papillary Lesions of the Oral Mucosa: A Review

Human papillomaviruses (HPVs) are causative of a group of clinically papillary lesions. The HPV-related lesions of the oral cavity include squamous papilloma, condyloma acuminatum, verruca vulgaris, and multifocal epithelial hyperplasia. Benign entities, such as verruciform xanthoma or giant cell fibroma, as well as malignancies, such as papillary squamous cell carcinoma and verrucous carcinoma, may be considered in the clinical and/or histologic differential diagnoses of these lesions. Mechanisms of infection, epidemiology, clinical presentations, histologic features, and differential diagnoses of the HPV-related oral pathologies are discussed. Current concepts of viral transmission, especially as pertaining to lesions in pediatric patients, and the impacts of HPV vaccination are reviewed.

Multiple Endocrine Neoplasia Type 2b (MEN2B) in a 9-Year-Old Female

Multiple endocrine neoplasia (MEN) is an uncommon genetic syndrome transmitted as an autosomal dominant condition characterized by multiple tumors or hyperplasia of neuroendocrine tissues. MEN type 2b (MEN2B) often has clinical signs of marfanoid facial appearance and mucosal neuromas of the head. This report describes the diagnosis of MEN2B in a previously undiagnosed 9 year old who presented for biopsy of an oral lesion.

Identification of intestinal ganglioneuromatosis leads to early diagnosis of MEN2B: role of rectal biopsy

BACKGROUND/PURPOSE

Gastrointestinal symptoms are very common in patients with multiple endocrine neoplasia type 2B (MEN2B) syndrome. Herein, we present a case of intestinal ganglioneuromatosis (IGN) in MEN2B syndrome and a systematic literature review with a special focus on gastrointestinal symptoms prior to the diagnosis of MEN2B.

METHODS

Literature search was performed (years 1966-2015) using the "Pubmed" and "Scopus" databases. Search terms used were gastrointestinal, intestinal and MEN2B.

RESULTS

Literature search revealed 188 publications on MEN2B patients with gastrointestinal symptoms, providing a total of 55 patients including our own case. The far most common gastrointestinal symptom was constipation (72.7%). The onset of gastrointestinal symptoms occurred in 29 out of 55 cases (52.3%) below the age of 1year. However, MEN2B diagnosis was established at a median age of 13.0years (range 0-46years). The histological finding of IGN led to the diagnosis of MEN2B In 15 of 55 patients (27.3%) at a median age of 3years (range 0-31years).

CONCLUSION

Paying close attention to gastrointestinal problems in early childhood and taking a rectal biopsy that precisely screens for IGN offers the chance of diagnosing MEN2B syndrome early in infancy.

Multiple endocrine neoplasia-2B presenting with orthodontic relapse

The multiple endocrine neoplasia (MEN) syndromes are a relatively uncommon group of genetic disorders characterized by the development of tumors in various endocrine organs. MEN type 2B is of particular interest to the dental profession because of its oral manifestations, which are often some of the earliest clinically detectable signs of the disorder. Early identification of this syndrome is critical because affected patients often develop a characteristic malignancy, medullary carcinoma of the thyroid, at a very early age. We describe a 17-year-old male whose initial diagnosis of MEN-2B was triggered by his orthodontist's request for an oral and maxillofacial pathology consultation to evaluate the patient's oral abnormalities.

RET oncogene mutations in medullary thyroid carcinoma in Mexican families

BACKGROUND

Different RET oncogene mutations have been found to be associated with inherited medullary thyroid carcinoma (MTC) in the context of three different syndromes including multiple endocrine neoplasia types 2A (MEN 2A) and 2B (MEN 2B) and familial medullary thyroid carcinoma (FMTC). These mutations have been recorded in different populations, but to date there is no corresponding study in Mexican families. Our purpose was identification of RET mutations in Mexican families with inherited or sporadic MTC (SMTC) and search for RET protein expression as prognostic marker in MTC tumors.

METHODS

Nine unrelated families with MTC corresponding either to two MEN 2A, three MEN 2B, or four SMTC were studied. Screening of exons 10, 11, and 13-16 of RET oncogene in DNA from circulating lymphocytes and tumor samples were analyzed. Immuno- staining for RET was performed in the corresponding tumor.

RESULTS

Germline 918 ATG-->ACG RET mutation was present in three unrelated MEN 2B individuals and corresponding somatic mutation in one individual with SMTC; 634 TGC-->TTC RET mutation was detected in two related patients in an MEN 2A family and the 634 TGC-->TAC RET mutation was detected in 12 related individuals from a second MEN 2A family. RET protein expression was detected in all MTC tumors showing different staining intensity.

CONCLUSIONS

RET mutations found in Mexican patients with MTC are similar to those previously reported in several MTC families worldwide. This indicates that RET mutations are highly conserved and that MTC etiology does not depend to a great extent on environmental factors or ethnic differences. Detection of RET protein in MTC tissue sections is not useful as prognostic marker.