Chasing a rarity: a retrospective single-center evaluation of prognostic factors in primary gliosarcoma

Gliosarcoma: A Multi-Institutional Analysis on Clinical Outcomes and Prognostic Factors

PURPOSE

This study describes oncological outcomes and investigates prognostic factors for patients with gliosarcomas (GSM).

METHODS

Histopathologically confirmed GSM patients who underwent treatment at five European institutions were retrospectively analyzed.

RESULTS

We analyzed 170 patients with a median clinical follow-up time of 9.2 months. The majority received surgery (94.1%), postoperative radiotherapy (pRT, 81.8%), and temozolomide (TMZ)-based postoperative chemotherapy (66.5%). The median overall survival (OS) and progression-free survival (PFS) were 12.3 and 6.6 months, respectively. In the multivariable Cox regression analysis (MVA), the following factors were significantly associated with OS: age per year (hazard ratio (HR): 1.03, p < 0.001), subtotal resection (STR) versus biopsy only (HR: 0.15, p = 0.018), gross total resection (GTR) versus biopsy only (HR: 0.13, p = 0.011), pRT versus no pRT (HR: 0.20, p < 0.001), postoperative TMZ-based chemotherapy versus no postoperative chemotherapy (HR: 0.44, p = 0.003), MGMT promoter non-methylated versus methylated (HR: 1.79, p = 0.05), and tumor diameter per cm (HR: 1.15, p = 0.046). For PFS, the following factors were significantly associated in the MVA: GTR versus biopsy only (HR: 0.19, p = 0.026), pRT versus no pRT (HR: 0.36, p = 0.006), postoperative TMZ-based chemotherapy vs. no postoperative chemotherapy (HR: 0.39, p < 0.001), MGMT promoter status unknown versus methylated (HR: 1.69, p = 0.034), and tumor diameter per cm (HR: 1.18, p = 0.016). Sex, primary or secondary GSM, and TP53 mutational status were not significantly associated with OS or PFS.

CONCLUSIONS

Trimodal therapy comprising surgical resection, pRT and TMZ-based chemotherapy appears to have the most beneficial effect on survival in GSM patients. Smaller tumor size, younger age and methylated MGMT promoters are associated with improved survival. To our knowledge, this is the largest multi-institutional cohort study investigating outcomes and prognostic factors for GSM.

Prognostic Factors for Patients with Primary Gliosarcoma: A Single-Center Retrospective Study

BACKGROUND

Primary gliosarcoma is a rare form of malignant central nervous system tumor, with limited understanding regarding its prognostic determinants and effective therapeutic interventions.

METHODS

The medical records of patients diagnosed with gliosarcoma at Tangdu Hospital between March 2011 and June 2023 were retrospectively analyzed in this study. Patients with a prior history of glioma or those who received preoperative chemoradiotherapy were excluded. Survival analyses were conducted using Kaplan-Meier and Cox regression analysis.

RESULTS

A total of 77 patients were included in the final analysis, with a median age of 57 years (range: 13-83). The predominant symptom leading to diagnosis was headache, and the temporal lobe was the most frequently affected site. Univariate analysis revealed that age ≤65 years, complete resection, Ki67 ≤ 25%, postoperative Karnofsky Performance Status ≥ 70, adherence to the Stupp protocol, and additional active therapy upon relapse were associated with enhanced survival. Furthermore, multivariate analysis identified complete resection, age ≤65 years, Stupp protocol treatment, and active therapy following relapse were independent predictors of overall survival. Notably, 1 patient experienced subcutaneous metastasis during treatment.

CONCLUSIONS

The present study's findings suggest that optimal management of primary gliosarcoma entails maximal safe resection, combined with adjuvant radiotherapy and chemotherapy with temozolomide, followed by salvage therapy in case of recurrence. However, the risk of metastases should be carefully monitored during the treatment course.

Primary Intracranial Gliosarcoma: Is It Really a Variant of Glioblastoma? An Update of the Clinical, Radiological, and Biomolecular Characteristics

Gliosarcomas (GS) are sporadic malignant tumors classified as a Glioblastoma (GBM) variant with IDH-wild type phenotype. It appears as a well-circumscribed lesion with a biphasic, glial, and metaplastic mesenchymal component. The current knowledge about GS comes from the limited literature. Furthermore, recent studies describe peculiar characteristics of GS, such as hypothesizing that it could be a clinical-pathological entity different from GBM. Here, we review radiological, biomolecular, and clinical data to describe the peculiar characteristics of PGS, treatment options, and outcomes in light of the most recent literature. A comprehensive literature review of PubMed and Web of Science databases was conducted for articles written in English focused on gliosarcoma until 2023. We include relevant data from a few case series and only a single meta-analysis. Recent evidence describes peculiar characteristics of PGS, suggesting that it might be a specific clinical-pathological entity different from GBM. This review facilitates our understanding of this rare malignant brain tumor. However, in the future we recommend multi-center studies and large-scale metanalyses to clarify the biomolecular pathways of PGS to develop new specific therapeutic protocols, different from conventional GBM therapy in light of the new therapeutic opportunities.

Prognostic Factors of Gliosarcoma in the Real World: A Retrospective Cohort Study

Purpose

Gliosarcoma is a histopathological variant of glioblastoma, which is characterized by a biphasic growth pattern consisting of glial and sarcoma components. Owing to its scarcity, data regarding the impact of available treatments on the clinical outcomes of gliosarcoma are inadequate. The purpose of this retrospective cohort study was to analyze the prognostic factors of gliosarcoma.

Methods

By screening the clinical database of neurosurgical cases at a single center, patients with gliosarcoma diagnosed histologically from 2013 to 2021 were identified. Clinical, pathological, and molecular data were gathered founded on medical records and follow-up interviews. Prognostic factors were derived using the Cox proportional hazards model with backward stepwise regression analysis.

Results

Forty-five GSM patients were included. Median overall survival was 25.6 months (95% CI 8.0-43.1), and median relapse-free survival was 15.2 months (95% CI 9.7-20.8). In multivariable analysis, total resection (p = 0.023, HR = 0.192, 95% CI 0.046-0.797) indicated an improved prognosis. And low expression of Ki-67 (p = 0.059, HR = 2.803, 95% CI 0.963-8.162) would be likely to show statistical significance. However, there might be no statistically significant survival benefit from radiotherapy with concurrent temozolomide (n = 33, 73.3%, log-rank p = 0.99) or adjuvant temozolomide (n = 32, 71.1%, log-rank p = 0.74).

Conclusion

This single-center retrospective study with a limited cohort size has demonstrated the treatment of gross total resection and low expression of Ki-67 which are beneficial for patients with GSM, while radiotherapy or temozolomide is not.