An 86-year-old patient consulted the maxillofacial surgery team at the San José Hospital Complex for an asymptomatic increase in volume, of undetermined evolution in the anterior mandibular area.
The patient had a personal history of hypertension and type 2 diabetes controlled by conventional medical treatment. She had no history of smoking or alcohol consumption.
Physical examination revealed a large increase in volume in the anterior mandibular region of firm consistency and painful on palpation. The skin and mucosa overlying the lesion were normal, with no associated lymphadenopathy. There was also no associated motor or sensory neurological involvement.
A computed tomography (CT) scan was requested, where axial images showed a hypodense lesion with a multilocular appearance extending from the region corresponding to the right canine area to the contralateral region corresponding to the left first molar, which generated bulging, thinning and perforation of bone tables. An incisional biopsy was scheduled and a drainage tube was installed in order to decompress the lesion.

Histopathological examination of the specimen revealed a cystic cavity lined by a parakeratinised poly-stratified epithelium with a basal stratum basale of ciliated cells with a hyperchromatic nucleus arranged in a palisade. Based on these findings the lesion was diagnosed as a keratocystic odontogenic tumour.

With this diagnosis it was decided to continue with decompressive therapy and to monitor the patient. After 2 weeks, the patient presented pain and functional impotence that increased to the point of preventing her from eating 2 months after the drain had been installed. With this evolution, a new CT scan was requested in which it was confirmed that the decompressive therapy was not fulfilling its objective, as an increase in tissue involvement was observed as a result of the lesion, in relation to the previous conditions, presenting clear destruction of both vestibular and lingual bone tables. Three weeks after the decompression procedure, and taking into account the new clinical and radiographic findings, excision of the lesion was performed plus curettage and application of Carnoy's solution for 30 seconds on the operative site. The underlying bone defect was reconstructed using a mandibular reconstruction plate. The surgical specimen was sent for histopathological study, which reported the presence of a cystic membrane with anaplastic epithelial tissue, with loss of epithelial stratification, cellular and nuclear pleomorphism, loss of the nucleus/cytoplasm ratio, prominent nucleoli, among others. The neoplastic proliferation showed an infiltrative pattern towards the underlying connective tissue. In other areas of the sample, nests and islets of epithelial proliferation were observed in the thickness of the cystic wall, which showed the same anaplastic characteristics. Based on these histopathological findings, a diagnosis of moderately differentiated intraosseous squamous cell carcinoma was made.
In view of this diagnosis, imaging tests were requested, including chest X-ray, total bone scan and bone scintigraphy, which ruled out metastases and/or possible primary tumours.
The patient was referred for oncological treatment and died of pneumonia.