[Two cases of metastatic brain tumor treated by interstitial brachytherapy]

The prognosis of patients with metastatic brain tumor is very poor. Median survival of these patients has ranged from 1 month with no therapy, to 2 months with steroid, and from 3 to 6 months with brain radiation therapy of the whole brain. A more recent study comparing radiation therapy alone with surgery plus radiation, has shown good results in the combined surgery and radiation therapy group. But surgical excision is usually limited to patients with a surgically accessible solitary metastasis. And therapeutic options are limited once the tumor recurs locally after whole brain irradiation. Interstitial irradiation allows the delivery of a high dose of localized irradiation in the area of tumor recurrence with minimal risk of radiation damage to the surrounding brain tissue. But brachytherapy for brain metastasis has been performed in few cases. We reported two patients with unresectable metastatic brain tumors who were successfully treated with iridium-192 interstitial brachytherapy, and we discuss the strategy of the treatment. Case 1: A 78 year-old-man underwent a total gastrectomy for gastric cancer. Five months after surgery, he developed right hemiparesis. CT scan revealed a left occipital tumor with massive brain edema and a tiny nodule of tumor in the left thalamic region. The primary site was well-controlled and no systemic disease was seen during subsequent whole body examination. The occipital lesion was surgically excised and he received a postoperative radiation therapy of 50 Gy to the whole brain. The thalamic tumor had not responded to the irradiation and the size of tumor rapidly increased.(ABSTRACT TRUNCATED AT 250 WORDS)