YO23 - Soft tissue Giant cell tumor presented as Nasopharyngeal mass: A case report

Case summary

Soft tissue Giant cell tumor presented as Nasopharyngeal mass : A case Report

ABSTRACT:

Background:

Primary soft tissue giant cell tumors are exceedingly rare. These often present in the elderly and are mostly noted on the extremities. Morphologically, these tumors resemble their osseous counterparts but sequencing studies have suggested that these two may be genetically distinct. Surgical extirpation remains standard of treatment; but for those with unresectable disease treatment options are less clear. For these patients, the use of bisphosphonates and RANK-L directed biologic therapy have been reported in the literature.

Case presentation:

A 30 year old male consulted at our medical oncology clinic with the chief complaint of diplopia. Magnetic resonance imaging (MRI) of the head revealed an enhancing soft tissue mass at the nasopharyngeal wall measuring 5.8x5.5x5.1cm extending anteriorly at the posterior margin of the nasal cavity, both parasellar regions, leptomeningeal region of the medial aspect of both middle cranial fossa, and infiltrating into the clivus. No distant metastasis was seen. Punch biopsy of this nasopharyngeal mass favored a giant cell tumor. Immunohistochemical staining was done with the following results: Cytokeratin negative, CD68 positive, and Vimentin positive, all consistent with giant cell tumor. Due to its location, the tumor was regarded to be unresectable. Zoledronic acid was given once every 28 days for 3 months. Cranial CT scan done after three months of treatment revealed an enhancing nasopharyngeal mass measuring 6.0x5.0x4.0cm with intracranial extension. At this time despite demonstrating stable disease, the patient was noted to have worsening of symptoms and was then shifted to Denosumab.

Conclusion:

We have reported a case of a nasopharyngeal giant cell tumor, which is an uncommon presentation of a rare soft tissue tumor. While surgery is the preferred treatment for this disease, the location of this tumor precluded resection. This has prompted the decision to employ systemic treatment with Zoledronic acid and subsequently Denosumab for this patient.

Clinical trial identification

Editorial acknowledgement