RESUMEN
OBJECTIVE: One challenging feature of head and neck pathology is that a dizzying array of spindle cell lesions occurs here which ranges all the way from reactive, very aggressive forms to malignant lesions. Leiomyosarcoma is one such malignant tumour of mesenchymal origin exhibiting smooth muscle differentiation; presenting generally nonspecific signs and symptoms. Here we present a case of leiomyosarcoma in a 21 year old female patient associated with single reddish pink swelling present in the posterior right maxillary tuberosity region with moderate facial asymmetry. On histopathological analysis, all the classic features were noted and diagnosis of a spindle cell neoplasm was made without any obscurity. There are many lesions like rhabdomyosarcoma, fibrosarcoma, liposarcoma, multiple peripheral nerve sheath tumour, angiosarcomas, melanomas, kaposi sarcoma, solitary fibrous tumors, etc., which mimic leiomyosarcoma clinically and histopathologically and therefore immunohistochemical staining with specific markers plays a vital role in arriving at a conclusive diagnosis.