Malignant fibrous histiocytoma of the mandible – A case report and review of published case reports

Abstract

The natural history of malignant fibrous histiocytoma (MFH) is still heavily debated. It's anonymous natural history is precisely denoted by its new adapted terminology 'undifferentiated pleomorphic sarcoma (UPS)'. Thus to diagnose a lesion as UPS, it is vital to correlate its histopathological features along with its immunohistochemical (IHC) expressions to confirm the tumor cell lineage. MFH is extremely rare in mandible with the literature search in PubMed database revealing only 13 case reports of MFH involving the mandible. Among these, only 7 case reports provide IHC details of the case. Without IHC data it is not possible to determine the accuracy of the diagnosis in the remaining 6 cases. Here we report an additional 8th case of MFH involving the ramus and angle of the mandible. Histopathology revealed proliferating malignant spindle cells interspersed with histiocyte-like cells. The tumor cells were strongly positive for vimentin and CD68 and were negative for S-100, epithelial membrane antigen (EMA) and cytokeratin (CK). The diagnosis was made by correlating the histopathological findings with the IHC profile. The report also provides the data (clinical, radiographic, histopathological, immunohistochemical features and treatment details) extracted from the 7 confirmed MFH case reports involving the mandible.

Secondary undifferentiated pleomorphic sarcoma of the mandible in a HIV patient who underwent radiotherapy for oral carcinoma

“…4,12 Most of them appear as primary tumors (70%), while secondary UPS are relatively less frequent and closely associated to preexistent conditions (30%), such as radiation therapy or trauma on the affected area. 1,5 An history of antecedent traumatic event is reported in about 20% of cases suggesting that some of these tumors may represent an initial proliferative response to trauma. 1,5,12 Almost 50% of all cases of UPS arises from the soft tissues of the extremities, limbs, and retroperitoneum.…”

“…1,5 An history of antecedent traumatic event is reported in about 20% of cases suggesting that some of these tumors may represent an initial proliferative response to trauma. 1,5,12 Almost 50% of all cases of UPS arises from the soft tissues of the extremities, limbs, and retroperitoneum. 4 Head and neck region is involved in only the 3-7% of the cases.…”

“…1 The majority of UPS is diagnosed as primary tumors, while secondary UPS are relatively less common and usually associated with a history of radiotherapy of the affected area. 5 Ionizing radiations are considered an important etiologic factor for secondary UPS and, due to increased use of radiotherapy, their incidence increased significantly during the last decades. 2 © 2021 Special Care Dentistry Association and Wiley Periodicals LLC UPS is more commonly localized at arms and legs' soft tissues, but can also affect bone, mainly femur, tibia and homer, causing pain, swelling and, in some cases, pathological fractures.…”

“…3 UPS rarely affects the head and neck region and it is even more sporadic in the jaw bones. 4,5 UPS of the head and neck usually appears as a painless and firm growing-mass, which infiltrates the surrounding tissues in the absence of pathognomonic signs and symptoms. 6 When the bone is involved, radiographic features may vary from radiolucency to a mixed radiolucent/radio-opaque appearance.…”

“…6 When the bone is involved, radiographic features may vary from radiolucency to a mixed radiolucent/radio-opaque appearance. 5 UPS is a diagnosis by exclusion and histological examination associated with F I G U R E 1 Clinical appearance of the growing and multilobulated intraoral mass immunohistochemical staining are mandatory to obtain definitive diagnosis of oral UPS. 6 Considering the histopathological appearance, five different subtypes have been described: storiform/ pleomorphic, myxoid, giant cell, inflammatory, and angiomatoid.…”