No prognostic differences between GBM-patients presenting with postoperative SMA-syndrome and GBM-patients involving cortico-spinal tract and primary motor cortex

Background: The supplementary motor area (SMA) is involved in several aspects of motor control and its can be associated to a contralateral motor deficit and speech disorders. After the resection of low-grade gliomas, this syndrome is diffusely reported but it is rarely investigated in high-grade gliomas. SMA deficits may resolve completely or with minor sequelae within weeks. Whether this condition of transient deficit affects survival, was not previously investigated, and is not currently understood. Objective: The study aimed to perform an accurate investigation concerning the real clinical and prognostic impact of the postoperative SMA syndrome in order to shed light over its relationship to survival parameters and postoperative functional status of the patients. Methods: We performed a retrospective review of a series of 176 surgically treated patients suffering from Glioblastomas. Tumors classified as Group A: Involving the SMA and Group B: Lesion located outside and distal to the SMA but in anatomical relationship to primary motor cortices (PM1) or corticospinal tract (CST), in order to investigate differences concerning immunohistochemical and molecular profiles in regard to the survival parameters. Results: Although lesions involving SMA demonstrated a significantly higher volume in respect to their general counterparts they did not significantly differ in concerns to the molecular patterns, pre and postoperative KPS scores and in PFS and OS findings. Conclusions: In our cohort SMA-syndrome is reversible and therefore guarantees a satisfactory functional status at follow-up, apparently not compromising survival when compared to other lesions affecting the primary or cortical motor area -spinal tract.