Oral soft tissue growths and swellings encompass focal reactive overgrowth (FROG), benign and malignant tumours. The diagnosis of these lesions is usually based on characteristic clinical and histopathological features. On rare occasions the clinical appearance of these is deceptive, exhibiting a benign appearance, whereby histopathology of the lesion will resolve the problem.
This poster presents a rare case of high grade mesenchymal chondrosarcoma (MS) of mandibular gingiva in a 34 year-old male that was clinically misdiagnosed as pyogenic granuloma (FROG). MS is rare and represents approximately 1% of all chondrosarcomas with a predilection to affect the maxillofacial skeleton area. MS usually presents as a lobulated firm mass with a tendency to erode and expand bony confines. The current case radiologically showed ill-defined and ragged borders originating from the medullary portion. Histologically the tumour exhibited a classic biphasic pattern. The diagnosis was confirmed with IHC markers. This case illustrates the importance of a thorough clinical, radiological and histopathological evaluation to avoid mismanagement.
Keywords: mesenchymal chondrosarcoma , misdiagnosis, focal reactive overgrowth, rare, maxillofacial skeleton, ragged borders, biphasic
