Development of a disease-specific graded prognostic assessment index for the management of sarcoma patients with brain metastases (Sarcoma-GPA)

Brain Metastases in Sarcomas: A Multicenter Retrospective Cohort Study

PURPOSE

Brain metastases (BM) in sarcomas occur rarely and are associated with poor prognosis. This study is a large retrospective cohort describing the demographic and clinical characteristics of these patients, treatment strategies, and survival outcomes.

METHODS

In total, 81 patients with BM from sarcomas were identified across five sarcoma centers. Demographic data, clinical presentation, and treatment modalities were analyzed.

RESULTS

The most common histologies were leiomyosarcoma (12.3%) and undifferentiated pleomorphic sarcoma (12.3%). The median time from sarcoma diagnosis to brain metastases was 1.9 years. Upon presentation, 88.9% of patients with BM from sarcomas were symptomatic with the most common presenting symptom being focal neurological deficits (37.9%) and headaches (22.1%). Higher-grade sarcomas were more likely to metastasize and were usually preceded by metastases to other sites, most commonly the lungs. One-year overall survival was 31% from initial sarcoma diagnosis, and the median time from diagnosis of BM until death was 6.0 months. For treatment, 60 (74.1%) patients had radiation, 39 (48.1%) patients had systemic therapy, and 29 (35.8%) patients had surgery. In a multivariate analysis, surgery (HR 0.30) and chemotherapy (HR 0.23) were found to be significantly correlated with improved survival outcomes. Although radiation as a whole was not found to significantly correlate with survival, improved outcomes were seen with stereotactic radiosurgery (SRS, mOS 11.6 mo) as opposed to whole-brain radiation therapy (WBRT, mOS 8.3 mo). Additionally, patients with leptomeningeal disease were significantly less likely to survive more than one year compared to patients with brain metastases only.

CONCLUSIONS

Our findings identify that patients with metastatic sarcoma to the brain have poor prognoses, often have concurrent metastasis, and have a median survival of only 6 months. Additionally, our study found that leptomeningeal metastases is a rare presentation with poor survival outcomes. There are various treatment modalities for sarcomas with BM; however, there are no guidelines, unlike in other malignancies. Further research is necessary to evaluate the role of therapeutic measures in terms of type, timing, and outcomes.

Predicting Survival with Brain Metastases in the Stereotactic Radiosurgery Era: are Existing Prognostic Scores Still Relevant? Or Can we do Better?

Predicting survival is essential to tailoring treatment for patients diagnosed with brain metastases. We have evaluated the performance of widely used, validated prognostic scoring systems (Graded Prognostic Assessment and diagnosis-specific Graded Prognostic Assessment) in over 1000 'real-world' patients treated with stereotactic radiosurgery to the brain, selected according to National Health Service commissioning criteria. Survival outcomes from our dataset were consistent with those predicted by the prognostic systems, but with certain cancer subtypes showing a significantly better survival than predicted. Although performance status remains the simplest tool for prediction, total brain tumour volume emerges as an independent prognostic factor, and a new, improved, prognostic scoring system incorporating this has been developed.

Navigating Post-Operative Outcomes: A Comprehensive Reframing of an Original Graded Prognostic Assessment in Patients with Brain Metastases

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.

Development and adaptations of the Graded Prognostic Assessment (GPA) scale: a systematic review

The Graded Prognostic Assessment (GPA) score has the best accuracy among prognostic scales for patients with brain metastases (BM). A wide range of GPA-derived scales have been established to different types of primary tumor BM. However, there is a high variability between them, and their characteristics have not been described altogether yet. We aim to summarize the features of the existent GPA-derived scales and to compare their predictor factors and their uses in clinical setting. Medline was searched from inception until January 2023 to identify studies related to the development, update, or validation of GPA. The initial search yielded 1,083 results. 16 original studies and 16 validation studies were included, comprising a total of 33,348 patients. 13 different scales were assessed, including: GPA, Diagnosis-Specific GPA, Extracranial Score, Lung-molGPA, Updated Renal GPA, Updated Gastrointestinal GPA, Modified Breast GPA, Integrated Melanoma GPA, Melanoma Mol GPA, Sarcoma GPA, Hepatocellular Carcinoma GPA, Colorectal Cancer GPA, and Uterine Cancer GPA. The most prevalent prognostic predictors were age, Karnofsky Performance Status, number of BM, and presence or absence of extracranial metastases. Treatment modalities consisted of whole brain radiation therapy, stereotactic radiosurgery, surgery, cranial radiotherapy, gamma knife radiosurgery, and BRAF inhibitor therapy. Median survival rates with no treatment and with a specific treatment ranged from 6.1 weeks to 33 months and from 3.1 to 21 months, respectively. Original GPA and GPA-derived scales are valid prognostic tools, but with heterogeneous survival results when compared to each other. More studies are needed to improve scientific evidence of these scales.

Brain metastases of sarcoma: a rare phenomenon in rare tumours

The usual site for distant metastases of sarcoma is lungs, while brain metastasis (BM) occurs much less frequently and usually late in the disease progression. Despite the advancement in cancer treatment, the outcome for patients with brain metastasis is poor, and their lifespan is short. The frequency of BM in sarcoma seems to be affected by the location and histology of the primary tumour. Sarcoma subtypes with a high propensity for brain metastasis are ASPS, leiomyosarcoma and osteosarcoma. There are no clear guidelines for the treatment of sarcoma brain metastasis. However, therapeutic options include surgery, radiotherapy and chemotherapy, and are often combined. Targeted therapies are a promising treatment option for sarcoma but require investigation in patients with BM. The following review presents the data on sarcoma brain metastasis incidence, treatment and prognosis.

A retrospective analysis of the prognosis of Japanese patients with sarcoma brain metastasis

BACKGROUND

Bone and soft tissue sarcomas are rare tumors and extremely rarely metastasize to the brain. Previous studies have examined the characteristics and poor prognostic factors in cases of sarcoma brain metastasis (BM). Due to the rarity of cases of BM from sarcoma, limited data exist concerning the prognostic factors and treatment strategies.

METHODS

A retrospective single-center study was performed on sarcoma patients with BM. The clinicopathological characteristics and treatment options for BM of sarcoma were investigated to identify predictive prognostic factors.

RESULTS

Between 2006 and 2021, 32 patients treated for newly diagnosed BM at our hospital were retrieved among 3133 bone and soft tissue sarcoma patients via our database. The most common symptom was headache (34%), and the most common histological subtypes were alveolar soft part sarcoma (ASPS) and undifferentiated pleomorphic sarcoma (25%). Non-ASPS (p = 0.022), presence of lung metastasis (p = 0.046), a short duration between initial metastasis, and the diagnosis of brain metastasis (p = 0.020), and the absence of stereotactic radiosurgery for BM (p = 0.0094) were significantly correlated with a poor prognosis.

CONCLUSIONS

In conclusion, the prognosis of patients with brain metastases of sarcomas is still dismal, but it is necessary to be aware of the factors associated with a relatively favorable prognosis and to select treatment options appropriately.

Brain Metastases from Adult Sarcomas: A Retrospective Cohort Study from the Hellenic Group of Sarcomas and Rare Cancers (HGSRC)

Brain metastases are rare events in patients with sarcoma and the available information is relatively limited. We retrospectively reviewed medical records of patients with sarcoma who developed brain metastases between April 2010 and April 2020 in six centers. Thirty-four adult patients were included with a median age at brain metastases diagnosis of 55.5 years (range, 18–75). The primary sarcomas originated either from soft tissue (n = 27) or bone (n = 7) and the most common subtypes were leiomyosarcoma (n = 8), Ewing sarcoma/peripheral neuroectodermal tumor (PNET) (n = 7) and osteosarcoma (n = 3). Most primary tumors were of high grade and located mainly in the extremities (n = 18). The vast majority of patients at the time of brain metastasis diagnosis already had extracranial metastatic disease (n = 26). The median time from sarcoma diagnosis to cerebral metastasis diagnosis was 16 months (range, 1–136). Treatment modalities for brain metastatic disease included whole-brain radiation therapy (WBRT) (n = 22), chemotherapy (n = 17), exclusive palliative care (n = 5), surgery (n = 9), targeted therapy (n = 6) or stereotactic radiosurgery (n = 2). Most patients experienced a progression of brain metastases (n = 11). The median overall survival from brain metastasis diagnosis was 3 months (range, 0–80). OS was significantly influenced by time-to-brain metastases (p = 0.041), WBRT (p = 0.018), surgery (p = 0.002) and chemotherapy (p = 0.006). In a multivariate analysis, only the localization of the primary (p = 0.047) and WBRT (p = 0.038) were associated with survival with statistical significance. Patients with sarcoma brain metastases have a particularly poor prognosis and an appropriate therapeutic approach is yet to be defined.

Outcomes of brain metastasis in high-grade bone and soft tissue sarcoma: An analysis of clinicopathological characteristics and survival data

Brain metastases in sarcoma are exceedingly rare, with few published series documenting ranges from 1% to 8%. This study investigated the outcomes of sarcoma patients with brain metastases using a population-based analysis. This was a retrospective review of 5933 patients with high-grade sarcoma identified from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Of the eligible 5933 patients, 0.7% (n = 44) had brain metastasis. Kaplan–Meier was used to estimate survival and follow-up (reverse Kaplan–Meier), and a multivariable Cox proportional hazards model analyzed prognostic factors of disease-free survival (DFS). Median (IQR) follow-up of all eligible patients was 28 months (12; 47). Patients who developed brain metastasis had a higher proportion of N1 stage disease (p < 0.001), as well as synchronous metastasis to bones, liver, and lungs compared to those without brain metastasis (all p < 0.001). The median (IQR) DFS with brain metastasis was 6 months (2; 12), and survival with brain metastasis was significantly worse than DFS in patients without brain metastasis (p < 0.001). Among those with brain metastasis only, there was no difference in DFS with respect to sex, race, primary tumor origin, T stage or N stage disease, synchronous metastasis to bone, liver or lung, nor with respect to chemotherapy or radiation for treatment of the primary tumor (all p > 0.05). For sarcoma patients with brain metastasis, the outcomes are poor and do not appear to differ by clinicopathologic factors. However, patients with certain histologies and synchronous metastases may warrant more frequent surveillance as there was an association of brain metastasis with these factors.