Fibrosarcoma epitelioide esclerosante a nivel paraespinal. Caso clínico y revisión de la literatura

Invasive sclerosing epitheloid fibrosarcoma in the lumbar spine- A rare case report

INTRODUCTION AND IMPORTANCE

Sclerosing epitheloid fibrosarcoma is a rare variant of low grade sarcoma with specific histologic and immunohistochemical features, and often associated with a poor prognosis.

CLINICAL PRESENTATION

We report a case of a 35-year old male who presented with 2 year history of lower back pain, radiating to both lower limbs, weakness to both lower limbs and weight loss more than 5kgs in the past 6 months, no past history of trauma, drenching night sweats, no TB contact history, no incontinence and no any comorbidities. He reported no history of alcohol intake or cigarette smoking, no history of exposure to radiations or similar presentation to his family and no features suggestive of metastasis. On examination - he had maximum midline tenderness L3-S1, no gibbous, upper limbs neurologically intact and power 3/5 to both lower limbs, sensation intact. Computed tomography scan and magnetic resonance imaging revealed an ill-defined osteolytic mass spanning L3 to L5, vertebral plana of L4 and involvement of the left paraspinal muscles. The tumor extended to the extradural space and was also abutting on the distal great vessels. Our intervention entailed laminectomy, tumor debulking and posterior instrumental fusion of the spine. Histopathology findings were in keeping with an invasive sclerosing epitheloid fibrosarcoma. He had adjuvant chemotherapy with good outcome.

DISCUSSION

This case was unique due to its lumbar column location, abutting the distal vessels and despite its low grade, it illustrates the malignant potential which responded well to adjuvant chemotherapy.

CONCLUSION

Invasive SEF is an aggressive tumor that requires early diagnosis. Multi-modal treatment with surgical resection, adjuvant chemotherapy can improve patient survival and quality of life.

Metastatic Pediatric Sclerosing Epithelioid Fibrosarcoma

Sclerosing epithelioid fibrosarcoma (SEF) is a rare and aggressive soft-tissue sarcoma thought to originate in fibroblasts of the tissues comprising tendons, ligaments, and muscles. Minimally responsive to conventional cytotoxic chemotherapies, >50% of SEF patients experience local recurrence and/or metastatic disease. SEF is most commonly discovered in middle-aged and elderly adults, but also rarely in children. A common gene fusion occurring between the EWSR1 and CREB3L1 genes has been observed in 80%–90% of SEF cases. We describe here the youngest SEF patient reported to date (a 3-yr-old Caucasian male) who presented with numerous bony and lung metastases. Additionally, we perform a comprehensive literature review of all SEF-related articles published since the disease was first characterized. Finally, we describe the generation of an SEF primary cell line, the first such culture to be reported. The patient described here experienced persistent disease progression despite aggressive treatment including multiple resections, radiotherapy, and numerous chemotherapies and targeted therapeutics. Untreated and locally recurrent tumor and metastatic tissue were sequenced by whole-genome, whole-exome, and deep-transcriptome next-generation sequencing with comparison to a patient-matched normal blood sample. Consistent across all sequencing analyses was the disease-defining EWSR1–CREB3L1 fusion as a single feature consensus. We provide an analysis of our genomic findings and discuss potential therapeutic strategies for SEF.