Submit Manuscript | http://medcraveonline.com Introduction Infammatory myofbroblastic tumour (IMT) is a rare pathology of unknown etiology. It was called infammatory pseudotumor (IPT) until 1998, when the term infammatory myofbroblastic tumour (IMT) was proposed as being a more descriptive name. 1 IMT and IPT terminologies are most confusing and interchangeably used due to very numerous similarities in histological presentations. But despite numerous similarities in histology/subtle differences such as marked spindle cell proliferation in IMT and prominent lymphoplasmacytic infltration in IPT help to histologically differentiate them. Immunohistochemical markers are invaluable in differentiating both of them. Though there is no signifcant difference in the clinical standpoint and are considered synonymous. 2,3 Now it is belong to the group of soft tissue tumours and have been known by various synonyms; infammatory pseudotumor, plasma cell granuloma, fbrous histiocytoma and sometimes low grade sarcoma or infammatory fbrosarcoma. 4−15 It was referred to by several different terms until the World Health Organization (WHO) classifed IMT as a distinct entity. 6 The diverse nomenclature is mostly descriptive and refects the uncertainty regarding its true biologic nature of these lesions. 7 Therefore IMT is clinico-pathologically distinctive but biologically controversial entity, which was originally described as true neoplastic lesion. 5−8 Exact etio-pathogenesis is not known, though it is considered to be an exaggerated infammatory reaction to tissue injury of unknown cause. 9 Recently the -concept of this lesion being reactive has been challenged based on the clinical demonstration of recurrences and metastasis and further cytogenetic evidence of acquired clonal chromosomal abnormalities. 10 Moreover the presence of human herpes virus-8 DNA sequences and the over expression of interleukin 6 and cyclin D1 have been reported in IMTs. 11 Then conception of infammatory origin was refuted by some researchers. Later it was described may arise as an immunologic host reaction to stimuli such as microorganisms (e.g Epstein –Barr Virus, Human Herpes Virus-8), foreign bodies or neoplastic tissues, chronic infammation and may even trauma. 12 Though in some studies found an association between trauma and IMT that may lead to reactive infammation has been suggested but causation cannot be proven completely. 10−12 Therefore whatever the cause a localized derangement in the immune response after the initial insult may be an underlying mechanism. 13 IMT is characterized by solitary, well demarcated mass with fbroblastic or myofbroblastic spindle cell proliferation with varying degrees of infammatory cell infltration. 1−14 There are three basic histologic patterns are recognized: a. Myxoid, vascular, and infammatory areas resembling nodular fasciitis; b. Compact spindle cells with intermingled infammatory cells (lymphocytes, plasma cells, and eosinophils) resembling fbrous histiocytoma; and Dense plate-like collagen resembling a desmoid or scar. These three patterns could overlap, or priority is given to (a) or (b), and this pathological classifcation method is universally accepted presently. 12 The differential diagnosis of the head and neck IMTs should include various benign and malignant spindle cell proliferations which may pose considerable histological overlap with IMTs. The main benign entities include nodular fasciitis, fbromatosis, myofbroma, myofbromatosis, solitary fbrous tumour, benign fbrous histiocytoma, Wegener’s granulomatosis, neural and smooth muscle lesions; the malignant differential diagnostic entities include fbrosarcoma, myofbrosarcoma, low-grade myofbroblastic sarcoma, malignant fbrous histiocytoma, spindle cell carcinoma, sarcomatoid carcinoma, leiomyosarcoma, rhabdomyosarcoma, and malignant peripheral nerve sheath tumour (MPNST). If there was a predominant J Dent Health Oral Disord Ther. 2017;8(2):476‒480. 476 ©2017 Sultana et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Infammatory myofbroblastic tumour, an unusual presentation in maxilla and paranasal sinuses: review of literature and a case report Volume 8 Issue 2 - 2017 Jachmen Sultana, 1 Abul Bashar, 2 Mohammed Kamal, 3 Sobhan Morol 1 1 Department of Oral and Maxillofacial Surgery, Dhaka Dental College and Hospital, Bangladesh 2 Department of Paediatrics, Comilla Medical College and Hospital, Bangladesh 3 Department of Pathology, Bangabandhu Sheikh Mujib Medical University, Bangladesh Correspondence: Jachmen sultana, Department of Oral and Maxillofacial Surgery, Dhaka Dental College and Hospital, Bangladesh, Email Received: June 09, 2017 | Published: September 13, 2017 Abstract Infammatory myofbroblastic tumours (IMT) are uncommon lesions, rarely affect the head and neck region. Its etio-pathogenesis and biological behaviour is still uncertain. IMT is just a reactive process or a true neoplasia is of great controversy. Because of its unpredictable biological behaviour and histopathological presentation clinically and radiologically it may simulate a malignant tumour. Though most of the IMT of head and neck shows a benign course but IMT of paranasal sinuses are highly aggressive in behavior with poor response to surgery, radiotherapy and chemotherapy, showing multiple recurrences and fatal outcome. Therefore management of IMT of maxillofacial region is challenging as there is no established protocol of treatment, but effort on individual IMT demonstrates its well response on combination regimen of prednisolone, methotrexate and celecoxib acid (cyclooxygenase 2 inhibitor) responds well and there is virtually total regression of the lesion. We hereby report a case of IMT in maxilla and paranasal sinuses and a review of its infammatory versus neoplastic behavior. Keywords: cyclooxygenase 2 inhibitor, infammatory myofbroblastic tumour, maxillary swelling, methotrexate, prednisolone, prognosis, treatment Journal of Dental Health Oral Disorders & Terapy Case Report Open Access