Challenging Diagnosis of Low-grade Fibromyxoid Sarcoma of the Chest Wall: Case Report

Abstract

Introduction: Low-grade fibromyxoid sarcoma (LGFMS) is a rare special subtype of fibrosarcoma, it is more common in the trunk and proximal limbs. First described by Evans in 1987, this tumor is also named Evans tumor. Diagnosis of LGFMS may be quite challenging, either due to the low suspicion rate of the tumor or low specificity of its morphological pattern and immunohistochemical profile, a phenomenon that is magnified when tumor location is less usual, such as in the chest wall. The present article presents a challenging case of LGFMS of the chest wall. Case report: Female, 58-year-old patient was referred to the oncology referral clinic with a breast tumor. Diagnostic investigation included imaging tests (breast US and chest CT scan) and core needle biopsy. CT scan revealed the epicenter of the tumor in the left anterior thoracic wall. Biopsy to evaluate the histologic type of tumor was carried out and the result was inconclusive. Therefore, surgical excision of the tumor was performed. Histopathology and immunohistochemistry studies of the surgical specimen confirmed the diagnosis of LGFMS of the chest wall. Currently, after 36 months of the surgical excision, the patient is still doing well and continues under clinical follow-up. Conclusion: Although the diagnosis of LGFMS of the chest wall is challenging, it should be done correctly, since these cases require a long and thorough clinical follow-up.