Ultrasonography During Surgery to Approach Cerebral Metastases: Effect on Karnofsky Index Scores and Tumor Volume.

BACKGROUND: The goals of treating a cerebral metastasis (CM) are to achieve local control of the disease and to improve patient quality of life. The aim of this study was to analyze the effect of conventional surgery supported by intraoperative ultrasound (IOUS) to approach a CM. To perform this analysis, we determined the postoperative Karnofsky Performance Status Scale (KPS) scores and tumor resection grades. METHODS: Patients with a CM diagnosis were included in this study. Surgical treatment was either supported or not by IOUS. Pre- and postoperative KPS scores were determined by the oncology team, and cerebral tumor volume was estimated through pre- and postoperative magnetic resonance imaging. The surgical team determined whether it was possible to perform a total CM resection. RESULTS: There were 78 patients treated using surgical management (35 with and 43 without IOUS). In the IOUS group, the postoperative KPS scores were higher (80 vs. 70, respectively; P = 0.045) and the KPS evolution was superior (P = 0.036), especially in the following subgroups: difficulty of tumor resection ranking score <4 (P = 0.037), tumor in an eloquent area (P = 0.043), tumor not associated with vessels or nerves (P = 0.007), and solitary lesions (P = 0.038). The residual tumor volume was lower in the IOUS group (9.5% and 1.6 mm3 vs. 30.8% and 9 mm3, respectively; P = 0.05). In patients with a KPS score ≥70, 62% of them had <10% residual tumors (76% in the IOUS group and 45% in the non-IOUS group; P = 0.032; odds ratio, 3.8). CONCLUSIONS: IOUS may improve postoperative KPS scores and decrease residual tumor volumes in CM surgeries. These findings should be confirmed in future studies.