Displasia fibrosa del maxilar inferior: dilema sobre su tratamiento, a propósito de un caso clínico

Abstract

Fibrous dysplasia (FD) is a rare bone disorder (7% of all benign bone tumors) difficult to diagnose, in which normal bone is replaced by fibrous tissue. It is etiologically related to a post-zygotic point mutation of the GNAS gene, for which it is necessary to rule out its association with McCune-Albright syndrome and hyperfunctioning endocrinopathies. This pathology can affect any bone, being less frequent a commitment of the lower jaw (LJFD) compared to the upper jaw, and its more commonly presented in children or adolescents. The diagnosis is based on clinical, radiological and histological findings. In addition to surgery, the use of bisphosphonates is a therapeutic option, with osteonecrosis of the jaw being a probable complication with the use of these drugs. Our objective is to describe the diagnosis, clinical evolution, follow-up and therapeutic management for a period of one year in a patient with DFMI, and to reconsider the available therapeutic options in the face of the probable appearance of complications.

This is a 39-year-old woman with an incidentally detected painless left mandibular lesion of 10x8 cm, visualized with tomography after which a biopsy was performed showing fibro-osseous proliferation, trabecular structures with a ground glass appearance, with the Chinese characteristic morphology immersed in a fibrous stroma, confirming bone fibrous dysplasia. Bone biochemical markers of formation and resorption were normal. The bone scintigraphy showed uptake only in the left mandibular region. A pituitary MRI showed a microadenoma interpreted as non-functioning with a normal hormonal profile. A conservative approach was adopted in the management of the patient, due to her stable medical condition and the absence of clinical and imaging changes in the one-year follow-up.

We conclude that the LJFD is a bone pathology of rare presentation and even more so in adulthood. Despite the favorable evolution of this case, we emphasize the need for strict clinical and radiological follow-up to detect possible local complications, malignant transformation or the appearance of new lesions. in these situations, a choice should be made between surgical therapy or antiresorptive pharmacological treatment, without ignoring the paradoxical but infrequent possibility of the appearance of osteonecrosis of the IM described in patients treated with these drugs.