Cesium-131 Interstitial Brachytherapy for Recurrent Malignancies of Skull Base

Background: Recurrent malignancy of the skull base poses a treatment challenge due to a lack of treatment options and potential for damage to surrounding structures.

Methods: Case report of two patients with recurrent nasopharyngeal carcinoma (NPC) of skull base previously treated with adjuvant chemoradiotherapy using intensity-modulated radiation therapy (IMRT).

Results: In both cases, the recurrent tumor was treated with endoscopic surgical resection and intraoperative placement of Cesium-131 (Cs 131) interstitial brachytherapy (IBT). Total dose delivered to tumor bed was 57 Gy and 60 Gy, respectively. With a half-life of 9 days, the majority of the radiation dose had been delivered within the first 40 days following implant and there have been no treatment-related complications reported.

Conclusion: Intraoperative Cs-131 IBT is a feasible adjuvant treatment option for patients with recurrent malignancies of the skull base. These are the first known cases of Cs-131 IBT used for recurrent NPC.