Maxillofacial brown tumours: Series of 5 cases

Lytic brown tumour of the mandible as the initial presentation of hyperparathyroidism in a 7-year old girl: A case report

INTRODUCTION AND IMPORTANCE

Maxillomandibular involvement with brown tumours is rare, especially in the paediatric population. We present a rare case of a young girl with brown tumour (BT) occurring in the mandible as the first manifestation of hyperparathyroidism.

CASE PRESENTATION

A 7-year-old black female, presented with a 6-month history of a swelling on the left mandible. Patient had a history of intractable gastrointestinal symptoms such as nausea, vomiting and abdominal cramps. Biopsy confirmed the lesion as a giant cell lesion. Elevated parathyroid hormone (PTH) levels confirmed the diagnosis of a BT of hyperparathyroidism. The patient underwent surgical intervention involving parathyroidectomy. This was followed by segmental resection of the mandibular tumour two years later.

CLINICAL DISCUSSION

Brown Tumour is a rare, non-neoplastic lesion resulting from abnormal bone metabolism secondary to hyperparathyroidism. BT predominantly arise in long bones and the axial skeleton. Maxillomandibular involvement is very rare. In the present case, after parathyroidectomy, normal PTH and calcium levels were restored, and there was relief of gastrointestinal tract hypercalcaemic symptoms. However, there was no spontaneous regression of the mandibular tumour over a 2-year observation period. Hemimandibulectomy followed by reconstruction with a plate and costochondral graft was then performed.

CONCLUSION

It is difficult to differentiate BT from other giant cell lesions without blood chemistry revealing hyperparathyroidism. The distinction is imperative to avoid mutilating and aggressive treatment for BTs. Although BTs are amenable for conservative treatment, the present case illustrates that for bigger tumours, in the absence of spontaneous regression, aggressive surgical treatment may be required.

Brown Tumour in Chronic Kidney Disease: Revisiting an Old Disease with a New Perspective

Osteitis fibrosa cystica (OFC) and Brown Tumours are two related but distinct types of bone lesions that result from the overactivity of osteoclasts and are most often associated with chronic kidney disease (CKD). Despite their potential consequences, these conditions are poorly understood because of their rare prevalence and variability in their clinical manifestation. Canonically, OFC and Brown Tumours are caused by secondary hyperparathyroidism in CKD. Recent literature showed that multiple factors, such as hyperactivation of the renin-angiotensin-aldosterone system and chronic inflammation, may also contribute to the occurrence of these diseases through osteoclast activation. Moreover, hotspot KRAS mutations were identified in these lesions, placing them in the spectrum of RAS-MAPK-driven neoplasms, which were until recently thought to be reactive lesions. Some risk factors contributed to the occurrence of OFC and Brown Tumours, such as age, gender, comorbidities, and certain medications. The diagnosis of OFC and Brown Tumours includes clinical symptoms involving chronic bone pain and laboratory findings of hyperparathyroidism. In radiological imaging, the X-ray and Computed tomography (CT) scan could show lytic or multi-lobular cystic alterations. Histologically, both lesions are characterized by clustered osteoclasts in a fibrotic hemorrhagic background. Based on the latest understanding of the mechanism of OFC, this review elaborates on the manifestation, diagnosis, and available therapies that can be leveraged to prevent the occurrence of OFC and Brown Tumours.

Spinal Cοrd Compression Secondary to Brοwn Tumοr as First Manifestation of Primary Hyperparathyroidism

BACKGROUND

Brown tumors (BTs) represent the typical nonmalignant lesions of hyperparathyroidism. Mandibles, ribs, and large bones are the most usual localization of BT. The diagnosis of these tumors requires biological and radiologic assessments. Their treatment is essentially based on parathyroidectomy.

CASE DESCRIPTION

The present case report describes a patient with primary hyperparathyroidism who developed a cervical BT revealed by slow spinal compression.

CONCLUSIONS

The brown tumor, when localized at the level of the spine, can be life-threatening and must be managed as soon as possible.