Myxoinflammatory fibroblastic sarcoma – report of a rare case at an unusual site with review of the literature

Abstract

We report a case of myxoinflammatory fibroblastic sarcoma in a thirteen year old girl who presented with a tender swelling in the left upper back. The tumor consisted of varying proportions of inflammatory, myxoid and hyalinized areas. Large bizarre cells with virocyte like inclusions and lipoblast like cells were present. To the best of our knowledge this is the first reported case of myxoinflammatory fibroblastic sarcoma of the back, the extremities being the commonest site of involvement. Due to its varied histologic appearance, the tumor should be differentiated from various benign and malignant soft tissue lesions.

Myxoinflammatory Fibroblastic Sarcoma: Report of a Case and Review of the Literature

“…Although myofibroblastic lesions account for about 12% of pediatric soft-tissue tumors in children, fewer than 10 MIFS have thus far been reported in childhood (Table 2) [1,[8][9][10][11].…”

Myxoinflammatory Fibroblastic Sarcoma in the Chest Wall

“…Tenosynovitis, ganglion cyst, and myxoma (for the inflammatory and benign entities), and myxoid malignant fibrous histiocytoma, myxoid liposarcoma, and epithelioid sarcoma (for the malignant tumors) are the main components of the histopathological differential diagnosis of a giant cell tumor in the tendon sheath or of a myxoid origin [2,5]. Because of the difficulty of an accurate diagnosis from the lesion's clinical presentation or radiological characteristics, the diagnosis is often delayed and a surgical excision is more likely to be suboptimal.…”

“…Premalata et al [5] reported upon a MIFS of the upper back, over the scapula. They performed a wide excision of the tumor, without rib resection, and reported no recurrence within 10 months after surgery.…”

Transformation of myxofibrosarcoma into myxoinflammatory fibroblastic sarcoma

“…Previous reports had suggested that myxofibrosarcoma is a difficult and important differential diagnosis of MIFS 2,4,5 . Histopathologically, however, myxofibrosarcoma and MIFS shared some feature with each other, such as various proportions of myxoid components and pleomorphic spindle/stellate cells in a myxoid background 5,6 .…”

“…Myxofibrosarcoma usually presents with markedly infiltrative growth but also can have a multinodular growth pattern, like MIFS 3 . MIFS is characterized by the presence of a myxoid matrix that contains inflammatory cells and variable, enlarged, atypical cells, including RS‐like cells, spindle/epithelioid cells, ganglion‐like, lipoblast‐like cells and bizarre giant cells 4–6 . Although pseudolipoblasts and multinucleated giant cells with ample cytoplasm can be seen in myxofibrosarcoma, it lacks the large ganglion/RS‐like cells of MIFS 6 .…”