|Ahead of print publication
Malignant fibrous histiocytoma - a case report
Mohaddeseh Imampanahi1, Safoura Seifi2, Mina Motllebnejad1, Marjan Kiani2, R Alireza Pournabi3
1 Department of Oral Medicine, Oral Health Research Center, Institue of Health, Babol, Iran
2 Department of Oral and Maxillofacial Pathology, Oral Health Research Center, Institue of Health, Babol, Iran
3 Department of Oral and Maxillofacial Surgery, School of Dentistry, Babol University of Medical Sciences, Babol, Iran
|Date of Submission||30-May-2018|
|Date of Acceptance||22-Dec-2018|
|Date of Web Publication||09-May-2020|
Department of Oral and Maxillofacial Pathology, Oral Health Research Center, Institute of Health, School of Dentistry, Babol University of Medical Sciences, Babol
Source of Support: None, Conflict of Interest: None
Fibrous histiocytoma is a mesenchymal neoplasm with benign and malignant varieties. This tumor mainly affects the skin of extremities in adults and may on rare occasions affect the oral cavity. The tumor has radiographic features in very rare cases. The present case report aims to conduct a clinicopathological-radiographic and immunohistochemical assessment and treatment of a patient with this lesion.
Keywords: Malignant fibrous histiocytoma, maxilla, mesenchymal neoplasm
| > Introduction|| |
Fibrous histiocytoma is a mesenchymal neoplasm that can occur in any part of the body, but that often appears as a painless cutaneous nodular lesion in the extremities. Intraoral lesions are rare. This tumor is rarely seen inside the bone. Malignant fibrous histiocytoma (MFH) is a high-grade sarcoma with aggressive behavior.,
Rare frequency, different histopathological views, and unknown etiology were associated with confusing results for surgeons and oncologists.
The present study aims to report a case of MFH in the maxilla of a 28-year-old man and its clinical, radiological, and pathological, immunohistochemical (IHC) assessment and treatment.
| > Case Report|| |
The patient was a 28-year-old man referred to the Oral Medicine Department of the School of Dentistry with the chief complaint of maxillary gingival abscess in the second-third right maxillary teeth, with no history of systemic diseases or medication allergy, but of a car accident 9 years ago with damage to the neck, head, and leg, for which he underwent several surgeries. According to the patient, the lesion had appeared in the gingiva of tooth 2–3 weeks earlier, with no changes in size over this period. The lesion had been drained once before by the patient but reappeared. The tooth involved was painless but became painful when the upper and lower teeth were pressed against each other. The patient was administered amoxicillin-metronidazole by a physician, but to no avail. Hence, he visited the School of Dentistry. In his clinical examination in the oral medicine department, a fluctuating and soft spherical mass was observed in the gingiva of tooth 2 that spread to the vestibule and was away from the gingival margin and the interdental papillae. The lesion had a smooth and erythematosus surface. The tooth was loose, but vital [Figure 1]. No lymph nodes were engaged.
A periapical radiographic assessment of this area revealed a well-defined radiolucency between the roots of teeth 2 and 3 with no cortical or sclerotic borders that had caused a mesial tilting of root 2 [Figure 2]. The differential clinical diagnosis was the presence of a central giant cell granuloma, an adenomatoid odontogenic tumor. The patient was referred to the oral surgery department, where the excisional biopsy was done in which the entire lesion was removed, and a sample was sent to the oral pathology department in formalin 10%.
|Figure 2: Periapical radiography shows well-defined radiolucency between 2 and 3 maxillary teeth|
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In a gross assessment of the lesion, a few pieces of irregularly shaped, cream-brown soft tissues with elastic consistency, covered in mucus, and of 3 cm × 1 cm × 0.3 cm dimensions were observed that appeared cystic with uniform thickness in sections.
In a microscopic assessment, a neoplastic structure of spindle-shaped mesenchymal origin was observed. The parenchyma consisted of spindle-shaped cells, some having wavy and comma-shaped nuclei and others vesicular nuclei. In some areas, histiocyte-like tumor cells were observed. The tumor stroma was fibrovascular, and the lesion was covered with parakeratinized stratified squamous epithelium of oral mucosa. The borderline spindle cell tumor was diagnosed, based on a microscopic view [Figure 3] and [Figure 4].
|Figure 3: Neoplastic proliferation of spindle-shaped cells (H and E, ×40)|
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Four months after the initial biopsy, recurrence was seen. Incisional biopsy was done. The final diagnosis was a malignant spindle cell tumor. There was >20 mitosis in 10 high-power fields (HPFs) [Figure 5].
For a definitive diagnosis of the lesion, the IHC assessment was conducted with CD68, vimentin, AE1/E2, CD34, S100, and αSMA, Ki67, cytokeratin, and desmin markers. According to the results obtained, the tumor was negative for desmin and S100. CD34 and αSMA were positive only in vascular areas, and cytokeratin was positive in the epithelium and negative in tumor areas. CD68 and vimentin also reported positive [Figure 5] and [Figure 6]. According to IHC results, the present mesenchymal tumor was not neuromuscular and was reported as an MFH.
Metastasis was found in the right and left lungs. The treatment was done with hemimaxillectomy and radiotherapy. There was no evidence of recurrence after 8 months.
| > Discussion|| |
MFH often occurs in the skin of extremities and rarely in the oral cavity, and its most common site is the buccal and vestibular mucosa. In relatively rare cases, this malignant mesenchymal tumor has been reported in the skull (mandible and maxilla) and paranasal sinus, gingiva, and the tongue. The involvement of oral soft tissue is more prevalent than the oral hard tissue. In the present report, the malignant mesenchymal tumor occurred in the buccal mucosa and maxillary bone of a 28-year-old man.
Such tumors usually affect middle-aged and older adults, although it was reported by Mori et al. in an 8-year-old patient. This tumor is more prevalent in women, but its occurrence has also been reported in men.
In a clinical view, MFH is seen as a painful nodular mass with trismus, which may also be painless in some cases., Vassiliou et al. reported a case of MFH in the tongue of a 43-year-old man. The patient had difficulty in swallowing from 15 days earlier. Senel et al. reported a painful swelling of the left body of the mandible in a 32-year-old woman with numbness in the lower lip. Kim et al. reported a 44-year-old man with a rapidly growing painful mass in the mandible within 2 months. He had no history of trauma. In the present report, the case was a painless swelling in the maxillary gingiva with a vital tooth, and evident bone involvement and the patient's reported a history of trauma to head and neck in a car accident 9 years ago. It is suggested that some of MFH may have been an initial proliferation response to trauma. The diagnosis of MFH is clinically difficult to identify, especially in cases where the tumor is deep and is usually diagnosed after the removal.
The question remains whether MFH is a reactive or neoplastic lesion. In most cases, it is believed that trauma and chronic infection influence its etiology. In the present report, the patient had a history of head-and-neck trauma. Senel et al. and Femiano et al. consider a history of trauma to be influential in the etiology of this tumor.
In a radiographic view with bone involvement, ill-defined radiolucency, or moth-eaten appearance is usually observed, but in this case report, a well-defined radiolucency was observed. Clinical and radiographic views indicated a benign lesion, but a mitotic count of >20 was observed in 10 HPF. The lesion was diagnosed as a malignant spindle cell tumor.
The histopathological view is nonspecific for MFHs. Since this tumor is a mesenchymal neoplasm, it may be mistaken for neural, muscular, or vascular neoplasms, and thus, IHC staining is necessary for its precise diagnosis., Accordingly, in the present report, the use of vimentin, αSMA, S100, CD34, AE1/E2, CD68, cytokeratin, and desmin markers was recommended.
In a report, certain cases of CD68 were used as a transmembrane protein to identify histiocytes, and positive stainability was observed with CD68 monocytes, histiocytes, osteoclasts, mast cells, and giant cells also becoming stainable. Identifying fibroblasts using vimentin showed positive stainability. Vascular and muscular tumors were excluded from the report due to the negative stainability of αSMA and CD34. Only blood vessel walls were stainable with αSMA and CD34. Stainability was negative with AE1/E2 and cytokeratin, and hence, the epithelial tumor was also excluded from the report. Due to nonstainability with desmin, skeletal muscle tumors were also excluded. In some areas, stainability with Ki67 was positive in >10%. Mitosis was found to be >10 in HPF with H and E staining, and the tumor was preferably considered as MFH.
MFH is treated with complete excision and radiotherapy, especially in larger and deep lesions. In the present case report, the lesion was totally removed, and hemimaxillectomy and radiotherapy were done. The overall survival for 5 years was 46%. Metastasis in the lung reduces the survival rate., In our case, metastasis in the lungs (right and left) was seen, but the patient was alive during the 6-month follow-up.
However, more invasive behavior is likely with the involvement of bone in MFH, and the patient should receive long-term follow-up.
| > Conclusion|| |
MFH is a rare oral cavity tumor but should undergo differential diagnosis of the soft- and hard-tissue lesions. Its definitive diagnosis is possible with clinicopathological and radiographic views with IHC staining. After the treatment, long-term follow-up is recommended.
Financial support and sponsorship
This study was financially supported by Babol University of Medical Sciences (No grant).
Conflicts of interest
There are no conflicts of interest.
| > References|| |
Prisse LA, Jayasooriya PR, Mendis BR, Lombardi T. Benign fibrous histiocytomas of the oral mucosa: Report on three cases and review of the literature. Dermatopathology (Basel) 2015;2:52-60.
Bala S, Augustine D, Murali S. Recurrent malignant fibrous histiocytoma of maxillary sinus: A case report. Int J Oral Maxillofac Pathol 2011;2:42-6.
Senel FC, Bektas D, Caylan R, Onder E, Gunhan O. Malignant fibrous histiocytoma of the mandible. Dentomaxillofac Radiol 2006;35:125-8.
Sreenivason B, Vinod VS, Mathew DG, George M. Undifferentiated pleomorphic sarcoma presenting as a gingival mass. A rare case. J NTR Univ Health Sci 2015;4:130-3.
Vassiliou A, Viastarakos PV, Manolopoulos L, Yiotakis I, Voros D, Carrouni E, et al
. Metastatic sarcoma of the tongue: Pleomorphic malignant fibrous histiocytoma and literature review. J Rhinolaryngol Otol 2014;2:10-3.
Mori Y, Motoi T, Ida K, Shibahara J, Saijo H, Susami T, et al
. Primary undifferentiated high-grade pleomorphic sarcoma/malignant fibrous histiocytoma arising from the mandible. Oral Sci Int 2014;11:70-5.
Kim CH, Jang JW, Kim MY, Kim YH, Kim HG, Kim JH, et al.
Undifferentiated pleomorphic sarcoma in mandible. Maxillofac Plast Reconstr Surg 2014;36:303-7.
Femiano F, Scully C, Laino G, Battista G. Benign fibrous histiocytoma (BHF) of the cheek: CD 68-KP1 positivity. Oral Oncol 2001;37:673-5.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]