Neuromuscular Choristoma: Report of Five Cases With CTNNB1 Sequencing.

Neuromuscular choristoma (NMC) are lesions of the peripheral nervous system characterized by an admixture of skeletal muscle fibers and nerves fascicles that are frequently associated with desmoid fibromatosis (DF). Mutations in CTNNB1, the gene for ß-catenin protein, are common in DF and related to its pathogenesis. They are restricted to exon 3, with 3 point mutations: T41A, S45F, and S45P. To understand the pathogenesis of NMC, we tested CTNNB1 status in 5 cases of NMC whether or not they were associated with DF. The screening of mutations in CTNNB1 gene was based on amplicon deep sequencing using the ION Proton platform. Three patients had the S45F mutation; in 2 the mutation was common to both lesions and in one the DF was wild type while the NMC had the S45F mutation. One patient had a T41A mutation in the NMC and no associated DF. In the last patient, the DF lesion had a T41A mutation; there was no lesion with the S45P mutation. The presence of similar CTNNB1 mutations in NMC/DF-associated lesions and sporadic DF reinforces the relationship between both lesions and points to a common pathogenic mechanism.

Enchondromas of the Hand: A 20-year Experience.

Objective Enchondromas are the commonest tumors of the bones of the hand. Treatment approaches vary. The present article presents the characteristics of the tumors, diagnostic methods, and treatments. Methods We discuss the approach used in our institution, where we have treated 48 patients with enchondromas of the hand between 1996 and 2016. Our technique of treatment, which has remained the same over 2 decades, comprises the use of curettage, high-speed burr, and autologous bone graft (harvested with a minimally invasive technique, using a Craig biopsy needle). Results Pain and fractures were the most common symptoms leading the patients to consultation, at frequencies of 33.3% and 31.3%, respectively. A total of 27.1% of the cases were asymptomatic, and their lesions were discovered incidentally. The mean age was 34.4 years (SD = 12.9 years). Tumors were more frequently presented in the ulnar side of the hand, in the fifth ray (41.5%) and in the proximal bones (in the proximal phalanges [43.8%], and in the metacarpal [33.3%]). The size of the tumors ranged from 0.2 cm 2 to 5.7 cm 2 , with a mean of 1.7 cm 2 (standard deviation [SD] = 1.0 cm 2 ) and were not associated with fracture ( p = 0.291). Fracture was also not associated with any of the symptoms, neither with the age of the patients ( p = 0.964). After the treatment, most patients achieved full range of motion (91.7%), with good integration of the bone graft. Three patients presented deficit in range of motion (6.3%) and the incidence of complications was also 6.3% (3 patients). At the end, after the needed surgical revisions, these three patients also recovered full function. They achieved full bone graft integration, regained full range of motion and returned to work. There was no tumor recurrence case during the follow-up period evaluated. For all cases, no donor site complications occurred. Conclusion Our method of treatment has consistently provided good outcomes, with only a few minor complications. Therapeutic level of evidence: IV.

Analysis of mutations in EXT1 and EXT2 in Brazilian patients with multiple osteochondromas.

BACKGROUND: Multiple osteochondromas is a dysplasia characterized by growth of two or more osteochondromas. It is genetically heterogeneous, caused by pathogenic variants in EXT1 or EXT2 genes in 70%-90% of patients. The EXT1 is more often mutated than EXT2 gene, with a variable prevalence between populations. There are no data about EXT1 and EXT2 pathogenic variants in patients with multiple osteochondromas in Brazilian population. The aim of this survey is to characterize these to determine the genotype profile of this population. METHODS: DNA sequencing (Sanger Method) and MLPA analysis were performed to identify point mutations and deletions/duplications in the sample of 153 patients in 114 families. RESULTS: Germline variants were identified in 83% of families in which EXT2 variants were detected in 46% and EXT1 in 37% of cases. No variants were detected in 17% of them. We identified 50 different variants, 33 (13 frameshift, 11 nonsense, 5 missense, 2 splice site mutation, and 2 large deletions) in EXT1 and 17 (6 frameshift, 6 splice site mutation, 3 nonsense, 1 missense, and 1 large deletion) in EXT2. Of all 50 variants, 31 (62%) were novel, including 20 out of 33 (60,6%) EXT1 and 11 out of 17 (64.7%) EXT2 alleles. The vast majority of variants (88%) were "loss-of-function" and two novel hotspots in EXT2 gene were observed in our study. CONCLUSION: The prevalence of variants detected in the EXT2 gene differs from other researches from Latin America, European, and Asian population. This uncommon prevalence could be related with the newly characterized variant hotspot sites detected in EXT2 gene (p.Ala409Profs*26 and p.Ser290*). A high number of novel variants were also identified indicating that Brazilian population has a unique genetic profile. Characterizing this population and establishing its genotype is essential to understand the molecular pathogenesis of this disease in Brazil.

Enchondromas of the Hand: A 20-year Experience / Encondromas da mão: Uma experiência de 20 anos

Abstract Objective Enchondromas are the commonest tumors of the bones of the hand. Treatment approaches vary. The present article presents the characteristics of the tumors, diagnostic methods, and treatments. Methods We discuss the approach used in our institution, where we have treated 48 patients with enchondromas of the hand between 1996 and 2016. Our technique of treatment, which has remained the same over 2 decades, comprises the use of curettage, high-speed burr, and autologous bone graft (harvested with a minimally invasive technique, using a Craig biopsy needle). Results Pain and fractures were the most common symptoms leading the patients to consultation, at frequencies of 33.3% and 31.3%, respectively. A total of 27.1% of the cases were asymptomatic, and their lesions were discovered incidentally. The mean age was 34.4 years (SD = 12.9 years). Tumors were more frequently presented in the ulnar side of the hand, in the fifth ray (41.5%) and in the proximal bones (in the proximal phalanges [43.8%], and in the metacarpal [33.3%]). The size of the tumors ranged from 0.2 cm2 to 5.7 cm2, with a mean of 1.7 cm2 (standard deviation [SD] = 1.0 cm2) and were not associated with fracture (p = 0.291). Fracture was also not associated with any of the symptoms, neither with the age of the patients (p = 0.964). After the treatment, most patients achieved full range of motion (91.7%), with good integration of the bone graft. Three patients presented deficit in range of motion (6.3%) and the incidence of complications was also 6.3% (3 patients). At the end, after the needed surgical revisions, these three patients also recovered full function. They achieved full bone graft integration, regained full range of motion and returned to work. There was no tumor recurrence case during the follow-up period evaluated. For all cases, no donor site complications occurred. Conclusion Our method of treatment has consistently provided good outcomes, with only a few minor complications. Therapeutic level of evidence: IV.

Resumo Objetivo Os encondromas são os tumores mais comuns dos ossos da mão, com uma grande variedade de abordagens terapêuticas. O presente artigo apresenta as características dos tumores, métodos diagnósticos e tratamentos. Métodos Discutimos a abordagem da nossa instituição, onde tratamos 48 pacientes com encondromas da mão, entre 1996 e 2016. Nossa técnica de tratamento, que permanece a mesma ao longo de duas décadas, compreende o uso de curetagem, esmeril de velocidade e enxerto ósseo autólogo (retirado com uma técnica minimamente invasiva, usando uma agulha de Craig). Resultados A dor e as fraturas foram os sintomas mais comuns, levando os pacientes à consulta, nas frequências de 33,3% e 31,3%, respectivamente. Um total de 27,1% dos casos era assintomático, e suas lesões foram descobertas incidentalmente. A média de idade foi de 34,4 anos (desvio padrão [DP] = 12,9 anos). Os tumores foram mais frequentemente encontrados no lado ulnar da mão, no quinto raio (41,5%), e nos ossos proximais (nas falanges proximais [43,8%] e no metacarpo [33,3%]). O tamanho do tumor variou de 0,2 cm2 a 5,7 cm2, com média de 1,7 cm2 (DP = 1,0 cm2) e não foi associado à fratura (p = 0,291). A fratura também não foi associada a nenhum dos sintomas, e nem à idade dos pacientes (p = 0,964). Após o tratamento, a maioria dos pacientes alcançou amplitude completa de movimento (91,7%), com boa integração do enxerto ósseo. Três pacientes apresentaram déficit no arco de movimento (6,3%) e a incidência de complicações também foi de 6,3% (3 pacientes). No final, após as revisões cirúrgicas necessárias, esses três pacientes também recuperaram a função completa. Eles tiveram a integração total do enxerto ósseo, recuperaram toda a amplitude de movimento e retornaram ao trabalho. Não houve nenhum caso de recorrência do tumor durante o período de acompanhamento avaliado. Em nenhum dos casos ocorreram complicações no local doador. Conclusão O nosso método de tratamento forneceu consistentemente bons resultados, com apenas algumas complicações menores. Nível terapêutico de evidência: IV.

Displasia camptomélica em gêmeas monozigóticas: estudo genético-clínico, radiológico e anatomopatológico / Camptomelic dysplasia in monozygotic twin sisters: genetico-clinical, radiological and pathological study

Säo apresentados dois casos de displasia camptomélica em gêmeas monozigóticas com cariótipo 46 XX. Caracterizam-se por membros inferiores curtos e encurvados, hipoplasia da cartilagem laringo traqueo-brônquica, desconforto respiratório grave, hipoplasia de escápulas, palato fendido, hipertelorismo, micrognatia, pés equinovaro-adutos e cicatriz pré-tibial. Um estudo genético-clínico, radiológico e anatomo-patológico, e revisäo de literatura säo apresentados. Säo considerados os achados fundamentais no diagnóstico diferencial com outras síndromes e salientados os aspectos de tipo de herança envolvidos. Na revisäo bibliográfica, näo foi encontrado relato de outro caso de gemelaridade