Isolated Xanthoma of the Frontal Bone

A Case Report of Craniofacial Intraosseous Xanthoma in a Patient Seeking Facial Feminization Surgery

BACKGROUND

Fibrous dysplasia (FD) is a benign developmental disorder of the bone that causes normal skeletal tissue to be replaced by excess fibrous tissue and poorly differentiated osteoblasts. Intraosseous xanthomas are benign intraosseous tumor growths characterized microscopically by the presence of lipid-laden foamy histiocytes, often with cortical expansion or disruption. Although FD commonly occurs in craniofacial bones, primary intraosseous xanthomas of the skull or facial skeleton are extremely rare. Although 2 distinct conditions, each may be difficult to differentiate on CT imaging when occurring in the facial skeleton.

METHODS

We report a case of an incidental finding on craniofacial CT of a frontal bone lesion originally thought to be FD. The finding was in a 55-year-old transgender woman who was assigned male at birth before receiving multiprocedural facial feminization surgery.

RESULTS

The clinical features, radiological findings, and treatment are discussed. Postoperatively, the patient had no sequelae secondary to facial feminization surgery or to the orbital lesion biopsy procedure. Bone graft appeared stable on CT imaging, although FD did not appear to resolve completely.

CONCLUSIONS

Diagnosis of such lesions is challenging and may require both radiographic and histopathologic assessment. As in the case of this patient, intraosseous xanthomas may also be misdiagnosed as other benign lesions such as FD. In most known cases, surgical intervention leads to complete resolution without recurrence of the lesion.

Xanthoma of rib: a case report and review of the literature

BACKGROUND

Xanthomas are well-circumscribed benign proliferative lesions seen mainly in soft tissues. Usually, they are found in hyperlipidemia and familial hyperlipoproteinemia. Histologically, are characterized by macrophage-like mononuclear cells, multinucleated giant cells and abundant foam cells. The bone involvement, however, is notoriously rare and rib localization is extremely rare.

CASE PRESENTATION

A 55-year-old man performed a chest X-ray and a subsequent chest Computed Tomography scan showing a rib lesion that was surgically removed and a diagnosis of rib xanthoma was made. The patient presented an unknown condition of hyperlipidemia.

CONCLUSION

Rib xanthoma can be discovered accidentally and can be helpful in identifying an unrecognized condition of hyperlipidemia.

Right Parietal Skull Xanthoma Characterized as a Metastatic Deposit

BACKGROUND

Xanthomas are benign lipomatous deposits that can be found systemically in various tissues including bones. Their presence in the skull remains a rare entity. Despite their benign characteristics, imaging modalities are often unable to distinguish them from malignant lesions. This leads to a diagnostic dilemma in patients with underlying malignancy. This case report highlights such a case where clinical history of prostate cancer and image findings were concordant with that of metastatic deposit in the parietal skull region.

CASE DESCRIPTION

This 65-year-old gentleman was diagnosed with prostatic adenocarcinoma. During systemic workup for his tumor, he was found to have a right parietal skull lesion. Magnetic resonance imaging of the brain, as well as a bone scan, were consistent with that of a metastatic deposit. As treatment would be drastically affected by the diagnosis, an excision biopsy was performed. The histology was consistent with that of a bone xanthoma.

CONCLUSIONS

Xanthomas are benign lesions that can be seen deposited in appendicular and axial skeleton. Skull lesions are rare with most case descriptions focusing on their presence in the frontoorbital regions and mandible and temporal bone. They usually have a benign course but may present with symptoms due to localized mass effect. Surgical intervention and histologic diagnosis may still be required in these lesions due to their lack of imaging characteristics that confirm their diagnosis through noninvasive methods.

Central xanthoma of the mandible associated with hyperlipidemia: A rare presentation

Xanthoma is a common, self-limiting cutaneous lesion of non-Langerhans cell, lipid-laden foamy histiocytes that is often concomitant with hyperlipidemia. The intraosseous counterpart is rarely encountered and typically presents as a painless, expansile osteolytic process in the context of hyperlipidemia or normolipidemia. Only a scant number of gnathic xanthomas have been reported in the otolaryngologic literature. We report the clinical, laboratory, radiographic, histopathologic, immunohistochemical, and ultrastructural studies of a mandibular lesion discovered in an asymptomatic 16-year-old male, and associated with 2 previously unreported comorbidities, namely hyperlipidemia and vitamin D deficiency.

Endoscopic endonasal resection of clival xanthoma: case report and literature review

Bone xanthoma is an extremely rare and benign tumor in terms of its nature and growth over time. We describe the first case coexisting with ventriculomegaly secondary to aqueduct stenosis (non-tumoral hydrocephalus), the second xanthoma of the clivus described to date. The patient was a 51-year-old woman with headaches and absence seizures. Axial T1-weighted MRI showed a well-demarcated, hypointense, osteolytic, 25 × 18 × 15 mm lesion with cortical erosion located at the right margin of the clivus. Sagittal T2-weighted MRI demonstrated a hypointense mass without associated edema. Sagittal gadolinium-enhanced T1-weighted MRI showed contrast uptake with a partially hypointense rim. The increased ventricular size without periventricular edema was associated with aqueduct stenosis, and there was no contiguity with the tumor. A neuronavigation image-guided transsphenoidal approach was chosen to perform a macroscopically complete resection. Intraoperative histopathological study showed a chordoma of the clivus. Exhaustive postsurgical study revealed the benign nature of a bone xanthoma. Given the finding of a clival lesion, the differential diagnosis is essentially with other malignant entities with a rapidly fatal outcome, such as metastases, or with a possible invasive evolution, such as clivus chordomas. This report describes the clinical, radiological, and pathological keys for such differentiation in order to avoid unnecessarily aggressive treatment with ablative surgery and radiotherapy.

Xanthoma of the occipital bone and with preserved inner and outer bone cortex: case report

Objective We present a unique case of a midline xanthoma of the occipital bone exhibiting atypical imaging characteristics with preserved bone cortex that has not previously been described.

Participant This man presented with refractory headaches and suboccipital pain and a mass within the diploe of the occipital bone but with preserved inner and outer cortex of the bone. Magnetic resonance imaging showed a midline, enhancing, and marrow-replacing process in the occipital bone measuring 1.5 cm in anteroposterior (AP) diameter, resulting in mild indentation of the dorsal aspect of the cerebellar vermis.

Results The patient underwent a suboccipital craniectomy. Tumor resection was from the foramen magnum to the inion and laterally until normal bone was encountered. The xanthoma was yellowish and bled a moderate amount upon resection.

Conclusion An isolated cranial xanthoma with preserved inner and outer bone cortex involving the occipital bone and of midline location has yet to be described. The differential diagnosis of osteoexpansile skull lesion with preserved bone cortex should now include xanthoma. Given the broad spectrum of imaging characteristics exhibited by this unusual diagnosis, surgical intervention is indicated from a diagnostic as well as a therapeutic standpoint.

A rare case of primary bone xanthoma of the clivus

Primary bone xanthoma is a rare type of tumor, and those developing primarily within the skull are even more unusual. In this case, a primary bone xanthoma of the clivus without endocrine or metabolic complications represents the first of this type to be reported. The patient, a 24-year-old woman, initially experienced frequent headaches. Subsequent skull tomography and bone-window computed tomography (CT) revealed a clearly demarcated osteolytic lesion in the clivus. T1-weighted magnetic resonance imaging (MRI) exhibited low intensity, and T2-weighted MRI showed iso-high intensity and a heterogeneously faint contrast effect. The tumor was completely resected, after which the patient's headaches disappeared completely. Because xanthoma is devoid of neoplastic features, it does not necessarily require aggressive therapy. Therefore, it is very important to understand the characteristics of its clinical symptoms and to give due consideration to differential diagnosis based on pathological presentations and imaging features. This study introduces information regarding a bone xanthoma originating within the skull, together with a review of bone xanthoma literature.

Xanthoma of Bone: A Case Report

Bone xanthoma is a rare disease due to the presence of cholesterol deposits in the bone. We report a case of a 56-year-old patient who was hospitalized in orthopedic department for fracture on the left humerus. Histological examination of bone biopsy performed at this site has objectified cholesterol deposits. Laboratory tests showed hypercholesterolemia with hypertriglyceridemia. The diagnosis of bone xanthoma was selected. The fracture was treated surgically. An initial bone scan revealed bone lesions localized especially at the humerus and femur. The patient was put under fenofibrate and statins. The evolution was marked by gradual regression of lesions in bone scans of control.