Cancer risk-reducing surgery: Brazilian society of surgical oncology guideline part 1 (gynecology and breast).

BACKGROUND: Risk-reducing operations are an important part of the management of hereditary predisposition to cancer. In selected cases, they can considerably reduce the morbidity and mortality associated with cancer in this population. OBJECTIVES: The Brazilian Society of Surgical Oncology (BSSO) developed this guideline to establish national benchmarks for cancer risk-reducing operations. METHODS: The guideline was prepared from May to December 2021 by a multidisciplinary team of experts to discuss the surgical management of cancer predisposition syndromes. Fourteen questions were defined and assigned to expert groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments, classified the level of evidence, and voted on the recommendations. RESULTS: For all questions including risk-reduction bilateral salpingo-oophorectomy, hysterectomy, and mastectomy, major agreement was achieved by the participants, always using accessible alternatives. CONCLUSION: This and its accompanying article represent the first guideline in cancer risk reduction surgery developed by the BSSO, and it should serve as an important reference for the management of families with cancer predisposition.

19q13.33→qter trisomy in a girl with intellectual impairment and seizures.

Rearrangements in chromosome 19 are rare. Among the 35 patients with partial 19q trisomy described, only six have a breakpoint defined by array. The 19q duplication results in a variable phenotype, including dysmorphisms, intellectual disability and seizure. In a female patient, although G-banding at 550 band-resolution was normal, multiplex ligation-dependent probe amplification (MLPA) technique and genomic array showed a 10.6 Mb terminal duplication of chromosome 19q13. Fluorescent in situ hybridization (FISH) revealed that the duplicated region was attached to the short arm of chromosome 21 and silver staining showed four small acrocentrics with nucleolar organization region (NOR) activity, suggesting that the breakpoint in chromosome 21 was at p13. This is the first de novo translocation between 19q13.33 and 21p13 described in liveborn. The chromosome 19 is known to be rich in coding and non-coding regions, and chromosomal rearrangements involving this chromosome are very harmful. Furthermore, the 19q13.33→qter region is dense in pseudogenes and microRNAs, which are potent regulators of gene expression. The trisomic level of this region may contribute to deregulation of global gene expression, and consequently, may lead to abnormal development on the carriers of these rearrangements.

Estudo clínico e molecular de pacientes com síndrome de Rett / Clinical and molecular study of patients with Rett syndrome

Objetivo: Estudar clinicamente pacientes brasileiras com síndrome de Rett, formas clássica e atípicas; pesquisar mutações de ponto no gene MECP2 e estabelecer correlação entre as principais mutações de ponto encontradas e o fenótipo das pacientes. Método: Foi realizada a avaliação clínica de 105 pacientes, incluindo 2 pares de gêmeas monozigóticas, seguindo um rigoroso protocolo clínico. A avaliação molecular do gene MECP2 foi realizada através de DNA extraído de sangue periférico e amplificação de sua região codificadora, que foi seqüenciada em seqüenciador automático. Resultados: Das pacientes estudadas, 68 por cento apresentavam a forma clássica; 27 por cento, formas atípicas e 5 por cento não puderam ser classificadas, dadas a idade e a clínica apresentadas. Foram encontradas mutações de ponto patogênicas em 64,1 do total das pacientes, 71,4 por cento das pacientes com a forma clássica, 50 por cento das pacientes com a forma atípica e 40 por cento das pacientes não classificadas. Foram encontradas 4 variações não descritas previamente, cuja natureza sugere que sejam patogênicas. As mutações mais freqüentes foram T158M (13 pacientes); R306C (11 pacientes e gêmeas), R168X (9 pacientes e gêmeas); R270X (7 pacientes); R294X (6 pacientes); R255X (5 pacientes). Observou-se uma freqüência maior de mutações de ponto identificadas entre as pacientes clássicas e um início precoce do quadro clínico nas pacientes sem mutações identificadas. As pacientes com mutação que geram um códon de parada prematura da leitura apresentaram um início mais precoce da doença e pontuações maiores na escala de Kerr do que as com mutações que trocam aminoácidos. As pacientes com mutações no sinal de localização nuclear (SLN) apresentaram um início precoce dos sintomas e as com mutações no domínio de repressão a transcrição após o SLN, apresentaram quadros menos graves...