ABSTRACT
INTRODUCTION: Spinal intradural tumors account for 15% of all CNS tumors. Typical tumor entities include ependymomas, astrocytomas, meningiomas, and neurinomas. In cases of multiple affected segments, extensive approaches may be necessary to achieve the gold standard of complete tumor resection. METHODS: We performed a bicentric, retrospective cohort study of all patients equal to or older than 14 years who underwent multi-segment surgical treatment for spinal intradural tumors between 2007 and 2023 with approaches longer than four segments without instrumentation. We assessed the surgical technique and the clinical outcome regarding signs of symptomatic spinal instability. Children were excluded from our cohort. RESULTS: In total, we analyzed 33 patients with a median age of 44 years and interquartile range IQR of 30-56 years, including the following tumors: 21 ependymomas, one subependymoma-ependymoma mixed tumor, two meningiomas, two astrocytomas, and seven patients with other entities. The median length of the approach was five spinal segments with a range of 4-14 and with the foremost localization in the cervical or thoracic spine. Laminoplasty was the most chosen approach (72.2%). The median time to follow-up was 13 months IQR (4-56 months). Comparing pre- and post-surgery outcomes, 72.2% of the patients (n = 24) reported pain improvement after surgery. The median modified McCormick scores pre- and post surgery were equal to II IQR (I-II) and II IQR (I-III), respectively. DISCUSSION: We achieved satisfying results with long-segment approaches. In general, patients reported pain improvement after surgery and received similar low modified McCormick scores pre- and post surgery and did not undergo secondary dorsal fixation. Thus, we conclude that intradural tumor resection via extensive approaches does not seem to impair long-term spinal stability in our cohort.
ABSTRACT
BACKGROUND: Graded Prognostic Assessment (GPA) has been proposed for various brain metastases (BMs) tailored to the primary histology and molecular profiles. However, it does not consider whether patients have been operated on or not and does not include surgical outcomes as prognostic factors. The residual tumor burden (RTB) is a strong predictor of overall survival. We validated the GPA score and introduced "volumetric GPA" in the largest cohort of operated patients and further explored the role of RTB as an additional prognostic factor. METHODS: A total of 630 patients with BMs between 2007 and 2020 were included. The four GPA components were analyzed. The validity of the original score was assessed using Cox regression, and a modified index incorporating RTB was developed by comparing the accuracy, sensitivity, specificity, F1-score, and AUC parameters. RESULTS: GPA categories showed an association with survival: age (p < 0.001, hazard ratio (HR) 2.9, 95% confidence interval (CI) 2.5-3.3), Karnofsky performance status (KPS) (p < 0.001, HR 1.3, 95% CI 1.2-1.5), number of BMs (p = 0.019, HR 1.4, 95% CI 1.1-1.8), and the presence of extracranial manifestation (p < 0.001, HR 3, 95% CI 1.6-2.5). The median survival for GPA 0-1 was 4 months; for GPA 1.5-2, it was 12 months; for GPA 2.5-3, it was 21 months; and for GPA 3.5-4, it was 38 months (p < 0.001). RTB was identified as an independent prognostic factor. A cut-off of 2 cm3 was used for further analysis, which showed a median survival of 6 months (95% CI 4-8) vs. 13 months (95% CI 11-14, p < 0.001) for patients with RTB > 2 cm3 and <2 cm3, respectively. RTB was added as an additional component for a modified volumetric GPA score. The survival rates with the modified GPA score were: GPA 0-1: 4 months, GPA 1.5-2: 7 months, GPA 2.5-3: 18 months, and GPA 3.5-4: 34 months. Both scores showed good stratification, with the new score showed a trend towards better discrimination in patients with more favorable prognoses. CONCLUSION: The prognostic value of the original GPA was confirmed in our cohort of patients who underwent surgery for BM. The RTB was identified as a parameter of high prognostic significance and was incorporated into an updated "volumetric GPA". This score provides a novel tool for prognosis and clinical decision making in patients undergoing surgery. This method may be useful for stratification and patient selection for further treatment and in future clinical trials.