AUTHOR=Krieg Sandro M. , Picht Thomas , Sollmann Nico , Bährend Ina , Ringel Florian , Nagarajan Srikantan S. , Meyer Bernhard , Tarapore Phiroz E. TITLE=Resection of Motor Eloquent Metastases Aided by Preoperative nTMS-Based Motor Maps—Comparison of Two Observational Cohorts JOURNAL=Frontiers in Oncology VOLUME=6 YEAR=2016 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2016.00261 DOI=10.3389/fonc.2016.00261 ISSN=2234-943X ABSTRACT=Introduction

Preoperative mapping of motor areas with navigated transcranial magnetic stimulation (nTMS) has been shown to improve surgical outcomes for peri-Rolandic lesions and, in particular, for gliomas. However, the impact of this technique on surgical outcomes for peri-Rolandic metastatic lesions is yet unknown.

Objective

To investigate the impact of nTMS on surgical outcomes for peri-Rolandic metastatic lesions, various clinical parameters were analyzed in our international study group.

Methods

Two prospectively enrolled cohorts were compared by investigating patients receiving preoperative nTMS (2010–2015; 120 patients) and patients who did not receive preoperative nTMS (2006–2015; 130 patients). Tumor location, pathology, size, and preoperative deficits were comparable.

Results

The nTMS group showed a lower rate of residual tumor on postoperative magnetic resonance imaging (odds ratio 0.3025; 95% confidence interval 0.1356–0.6749). On long-term follow-up, surgery-related paresis was decreased in the nTMS group (nTMS vs. non-nTMS; improved: 30.8 vs. 13.1%, unchanged: 65.8 vs. 73.8%, worse: 3.4 vs. 13.1% of patients; p = 0.0002). Moreover, the nTMS group received smaller craniotomies (nTMS: 16.7 ± 8.6 cm2 vs. non-nTMS: 25.0 ± 17.1 cm2; p < 0.0001). Surgical time differed significantly between the two groups (nTMS: 128.8 ± 49.4 min vs. non-nTMS: 158.0 ± 65.8 min; p = 0.0002).

Conclusion

This non-randomized study suggests that preoperative motor mapping by nTMS may improve the treatment of patients undergoing surgical resection of metastases in peri-Rolandic regions. These findings suggest that further evaluation with a prospective, randomized trial may be warranted.