Solitary Fibrous Tumor: An Uncommon Cause of Paraparesis and Sciatic Pain

Abstract

Solitary fibrous tumor (SFT) is a rare type of soft tissue neoplasia, usually seen in adults. They are mesenchymal neoplasias that appear to exhibit fibroblastic differentiation, classically described in the pleura, but can arise anywhere. They have a generally benign course; however, in rare cases, they may recur locally or at a distance. When surgery is not possible or in the presence of metastasis, chemotherapy or palliative radiotherapy may be therapeutic options. The patient was a 44-year-old man, a construction worker, healthy apart from a totally resected left pelvic SFT 3 years before. He was observed over the last several times in the emergency department (ED) by right sciatic pain and discharged. He had no history of trauma. A lumbar MRI was performed without alterations of relief. The worsening of the symptomatology, with commitment of the autonomous march, resorted him again to ED. Clinical features showed grade 2 strength with hypoesthesia and an aquiline reflex abolished in the right lower limb (MI) and strength grade 4+ at the distal level of the left MI. There was a palpable rounded swelling on the posterior aspect of the right thigh (5 × 8 cm), with an elastic and non-painful consistency at palpation. MRI of the neuro-axis showed no changes of relief. Pelvic CT showed swelling with soft tissue component, which invaded the iliac bilaterally and right sacroiliac joint, with lithic alteration. The histology of the pelvic lesion and thigh lesion revealed an SFT. Radiotherapy and then chemotherapy were performed. The patient died 1 year after the diagnosis. We report a fatal case of recurrence of SFT. The authors highlight the case because of its rarity and its “malignant” evolution. Long-term follow-up of these patients is required because of the risk of recurrence of these tumors and their uncertain biological behavior. J Med Cases. 2017;8(6):196-199 doi: https://doi.org/10.14740/jmc2843w