Brain ectopic tissue in sacrococcygeal region of a child, clinically mimicking sacrococcygeal teratoma: a case report

Background Mature brain heterotopic tissue in sacrococcygeal region is a very rare benign congenital abnormality of newborn. To date, only two cases of mature heterotopic brain tissue in the sacrococcygeal region is reported by literature. Heterotopic brain tissue in other areas such as lung, nose, face and retroperitoneal region are also rarely reported. Meanwhile, rather than brain heterotopic tissue in sacrococcygeal region, a case of adrenal gland heterotopic tissue in sacrococcygeal region also has been reported. Case presentation A 3.5 month-old male baby presented with history of sacrococcygeal mass since birth. Clinical examination of the child was good with no other problem. Sacrococcygeal region revealed an elevated round mass with no discharge. Computed tomography reported a large sacrococcygeal teratoma type-III arising from the sacrococcygeal region extending intra-abdominally to the level of L2 vertebral body. The mass was excised by the impression of sacrococcygeal teratoma (SCT). On gross examination, a gray-white irregular tissue fragment with 5 cm in greatest dimension was examined. Cut sections showed homogenous yellowish white appearance. Histological examination revealed solid fragments composed of mature neural tissue comprising glial cells and astrocytes with no other germ cell layer component. Conclusion Mature brain heterotopic tissue in sacrococcygeal area is a rare benign disease. Two ectopic brain tissue in sacrococcygeal region were previously also reported. Sacrococcygeal teratoma is the most common congenital tumor, but this current rare case of heterotopic brain tissue in sacrococcygeal region should also be in the differential diagnosis. Keywords: Congenital malformations, Heterotopic brain tissue, Sacrococcygeal teratoma