An unexpected diagnosis of paediatric subcutaneous sacrococcygeal extraspinal ependymoma: lessons learnt and review of the literature

Abstract

<jats:title>Abstract</jats:title> <jats:p>This case describes a 9-year-old male who presented to general surgical clinic with a 3-year history of persistent natal cleft swelling, previously unsuccessfully treated as a pilonidal abscess in the community with multiple courses of antibiotics. In clinic, a 50 × 30-mm soft tissue swelling was found in the natal cleft and a clinical diagnosis of a pilonidal cyst was made. A cream-coloured solid mass measuring 50 × 35 × 30 mm was subsequently excised under general anaesthetic, with specialist histology and immunostaining confirming an unexpected diagnosis of a subcutaneous extraspinal myxopapillary ependymoma, a tumour usually found in the neuraxis. Given the atypical anatomical site of the tumour, the case presented a unique management challenge. Ultimately, the patient underwent a re-operation after specialist multi-disciplinary discussion and is currently disease free at 18 months post-surgery. The authors wish to contribute their experiences of managing this rare extraspinal ependymoma to the few existing reports in the literature.</jats:p>

Surgical management of a rare myxopapillary ependymoma of the gluteal region: A case report

“…In our literature review, we found 38 studies that described 78 unique cases of myxopapillary ependymoma occurring in the sacrococcygeal region without extension into the CNS [ Table 1 ]. These were comprised of 35 case reports involving 1 or 2 patients,[ 1 , 3 , 4 , 6 - 14 , 17 - 19 , 21 - 26 , 28 , 31 , 33 - 35 , 38 - 41 , 43 , 45 , 47 , 48 , 50 ] and 3 case series involving 3–32 patients. [ 5 , 20 , 42 ] There were no comparative trials.…”

“…also reported extra CNS lesions that invaded the sacrum and caused left lower extremity pain, weakness, and dermatomal paresthesias in one case, and progressive weakness in bilateral lower extremities with bowel and bladder incontinence in the other. [ 11 , 19 ]…”

“…The primary means of management for sacrococcygeal myxopapillary ependymoma is complete surgical resection. [ 19 , 31 ] This entails excision of the mass along with neighboring sacrum or coccyx if they are involved within the tumor. A case series by Aktuğ et al .…”

Pediatric Extraspinal Sacrococcygeal Ependymoma: Report of Two Cases and Literature Review

“…More than a century ago, Mallory et al first described the case of an ependymoma that developed in the subcutaneous tissue of the sacrococcygeal region [ 9 ]. Since then, only a few cases have been reported in literature with less than 50 reported cases occurring in childhood during the last 35 years ( Table 1 ) [ 4 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. They occur more frequently in the sacrococcygeal region, followed by the pelvic region, while cases of onset in the liver, lung, or mediastinum are rarer and mainly described in adulthood [ 3 , 5 ].…”

“…The cases we have described also presented with a mass without associated symptoms, and the initial presumptive diagnosis were epidermoid cyst and germ cell tumor, respectively. In fact, given their localization and the propensity to drain which could suggest a diagnosis of pilonidal cyst or other benign tumors, misdiagnosis at onset is very common, occurring in virtually all cases described in the literature [ 5 , 28 , 34 , 44 ]. Thus, with any soft tissue lesion of the sacrococcygeal region, the differential diagnosis must include also ependymoma, in addition to sacrococcygeal teratoma, neurogenic tumor, soft tissue sarcoma, and metastatic carcinoma.…”