Complete Regression of a Solitary Cholangiocarcinoma Brain Metastasis Following Laser Interstitial Thermal Therapy.

Background: To our knowledge, we report the first case of a cholangiocarcinoma brain metastasis successfully treated with magnetic resonance imaging (MRI)-guided laser interstitial thermal therapy.

Case Description: In 2017, a 71-year-old man was diagnosed with unresectable intrahepatic cholangiocarcinoma. In August 2018, a brain MRI scan was performed after a transient episode of altered mental status and revealed a subcentimeter enhancing lesion in the deep white matter of the right cerebellum. Due to lack of symptoms and the small size of the lesion, it was initially observed. However, a follow-up MRI scan at 2.5 months demonstrated increased lesion size with worsening perilesional edema. Given the rarity of cholangiocarcinoma brain metastases and the deep location, the patient underwent stereotactic needle biopsy to confirm the diagnosis followed by laser ablation as a primary treatment for the metastasis. The patient tolerated the surgery well with no complications, and the postoperative course was uneventful. At 16 months postablation, there has been no recurrence or disease progression.

Conclusions: Although prognosis for these tumors is poor, our result suggests that laser ablation can be an effective treatment for this rare entity and is a representative example of the expanding indications for laser interstitial thermal therapy.