A 2-month-old male presents with a firm, non-tender midline sacrococcygeal mass noted on routine physical examination. The mass is located just superior to the coccyx. Imaging shows a well-circumscribed tumor containing mature bone, cartilage, adipose tissue, and disorganized neural elements. Genetic testing reveals a TP53 mutation. Which of the following embryologic abnormalities best accounts for this finding?

  1. A)Failure of fusion of the neural folds during primary neurulation
  2. B)Incomplete regression of the primitive streak and caudal eminenceGABARITO
  3. C)Abnormal migration of pluripotent neural crest cells to the midline
  4. D)Persistence of the neurenteric canal connecting notochord to endoderm
  5. E)Failure of notochord involution with ectopic notochordal remnants

Explicação

Sacrococcygeal teratomas arise from incomplete regression of the primitive streak and caudal eminence (tail bud) during weeks 4-6 of gestation. This region contains pluripotent mesenchymal cells capable of differentiation into multiple germ layers, explaining ... Ver explicação completa e trilha adaptativa →

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