[A case of low-grade fibromyxoid sarcoma of the colon]

Low-grade fibromyxoid sarcoma is a slowly growing soft tissue neoplasm that shows benign histologic features but may have clinical course of malignant disease. It has been reported to occur in the thigh, inguinal area, axilla, shoulder, neck, perineum or buttock. However, there have been few cases of abdominal organ involvement. A 21-year-old woman presented with a large palpable abdominal mass. A 7×4 cm sized round soft tissue tumor at right upper quadrant area was identified by abdominopelvic CT scan. Percutaneous ultrasound-guided biopsy revealed features of spindle cell tumor. On exploration, the tumor originated from transvers colon and was attached to gastrocolic ligament, transverse mesocolon and stomach. The tumor could be dissected with transverse colectomy and partial gastrectomy. The excised tumor, measuring 7×5×5 cm, was well demarcated and appeared as an ovoid mass with firm and myxoid cut surface. She was diagnosed with low-grade fibromyxoid sarcoma arising from transverse colon, and is currently being followed-up without recurrence or metastasis.