[Contribution of temozolomide chemotherapy for intramedullary grade II spinal cord astrocytomas in adults: Our experience]

Management and Outcome of Recurring Low-Grade Intramedullary Astrocytomas

Intramedullary astrocytomas (IMAs) are the second most frequent intramedullary tumors in adults. Low-grade IMAs (LG-IMA, WHO grade I and II) carry a better prognosis than high-grade IMAs (HG-IMAs). However, adjuvant treatment of LG-IMAs by radiotherapy (RT) and/or chemotherapy (CT) as well as treatment of tumor recurrences remains controversial. The aim of our study was to evaluate the postoperative outcome of LG-IMAs and the management of recurring tumors. We retrospectively reviewed a series of patients operated on for IMA from 1980 to 2022 in a single neurosurgical department. We retrieved 40 patients who received surgery for intramedullary astrocytomas, including 30 LG-IMAs (22 WHO grade I; 5 WHO grade II; 3 "low-grade") and 10 HG-IMAs (4 WHO grade III; 5 WHO grade IV; 1 "high-grade"). Of the patients with LG-IMAs, the extent of surgical resection was large (gross or subtotal resection >90%) in 30% of cases. Immediate postoperative radiotherapy and/or chemotherapy was proposed only to patients who underwent biopsy (n = 5), while others were initially followed-up. Over a median follow-up of 59 months (range = 13-376), 16 LG-IMA (53.3%) recurred with a mean delay of 28.5 months after surgery (range = 3-288). These included seven biopsies, five partial resections (PR), four subtotal resections (STR) but no gross total resections (GTR). Progression-free survival for LG-IMAs was 51.9% at 3 years and 35.6% at 5 and 10 years; overall survival was 96.3% at 3 years; 90.9% at 5 years and 81.9% at 10 years. There were no significant differences in terms of OS and PFS between WHO grade I and grade II tumors. However, "large resections" (GTR or STR), as opposed to "limited resections" (PR and biopsies), were associated with both better OS (p = 0.14) and PFS (p = 0.04). The treatment of recurrences consisted of surgery alone (n = 3), surgery with RT and/or CT (n = 2), RT with CT (n = 3), RT alone (n = 2) or CT alone (n = 2). In conclusion, although LG-IMAs are infiltrating tumors, the extent of resection (GTR or STR), but not WHO grading, is the main prognostic factor. The management of recurring tumors is highly variable with no conclusive evidence for either option.

A Prospective Clinical Study on MGMT Protein Expression and the Effect of Gene Promoter Methylation on Sensitivity to Chemotherapeutics in Spinal Glioma

Objective

The present study discusses the O6-methylguanine-DNA methyltransferase (MGMT) protein expression of spinal glioma cells and the correlation between the sensitivity of promoter methylation of the MGMT gene to chemotherapy drugs, establishes a prediction method for the sensitivity of chemotherapy drugs on spinal gliomas, providing a theoretical basis for determining the best chemotherapy regimens for clinical patients after a spinal glioma operation.

Methods

A total of 67 patients, who received microsurgical resection for spinal glioma from October 2010 to June 2016, were selected for the present study. Immunohistochemistry and methylation were performed after the operation. Among these patients, 47 patients with postoperative chemotherapy were assigned as the experimental group, while 20 patients without chemotherapy were designated as the control group.

Results

Among the 47 patients in the experimental group, 39 patients had no tumor recurrence after two years, while tumors increased and symptoms were aggravated in eight patients. The progression-free survival rate of chemotherapy was 82.9%, and the two-year survival rate was 100%. The adverse reactions of patients during chemotherapy were slight. Among the 20 patients in the control group, seven patients had no tumor recurrence, while 13 patients had increased tumor size, and the progression-free survival rate was 35.0%.

Conclusion

Under the guidance of MGMT immunohistochemical detection and MGMT gene promoter methylation detection after surgery, chemotherapy can effectively delay tumor recurrence, prevent a reoperation, and have good safety and tolerability. This chemotherapy regimen has good prospects.

Adult intradural intramedullary astrocytomas: a multicenter analysis

Background

Intramedullary tumors constitute approximately 20-30% of all spinal cord tumors and approximately 30-40% of these are astrocytomas. Furthermore, they comprise only about 2-4% of all primary central nervous system (CNS) tumors. Due to their rarity and poor prognosis, large population-based studies are needed to assess the epidemiology and survival risk factors associated with these tumors in the hope of improving outcomes. The authors undertook this retrospective study to explore factors that may influence survival in adult patients with intramedullary astrocytomas.

Methods

Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, a prospective cancer registry, the authors retrospectively assessed survival in histologically confirmed, intramedullary spinal cord astrocytomas in patients 18 years of age and older. Survival was described with Kaplan-Meier curves and multivariate regression analysis was used to assess the association of several variables with survival while controlling for confounding variables.

Results

Analysis by multivariate regression of 131 cases showed that increasing age of diagnosis [hazard ratio (HR) 1.52, 95% CI: 1.17-1.99, P=0.001], WHO grade IV classification (HR 8.85, 95% CI: 2.83-27.69, P<0.001), tumor invasiveness (HR 2.94, 95% CI: 1.00-8.64, P=0.047), and sub-total resection (HR 5.80, 95% CI: 1.20-28.03, P=0.029) were associated with statistically significant decreases in survival.

Conclusions

This study suggest that older age, higher WHO grade, tumor invasiveness as well as sub-total resection were all associated with a worse prognosis.