P11.23.B Neurological symptoms independently associate with overall survival in patients with melanoma brain metastases

Background

Based on the the rising detection of asymptomatic brain metastases (BM) and the remarkable intracranial responses of targeted- and immunotherapy in specific subgroups of asymptomatic BM patients, we aimed to evaluate the clinical characteristics and prognostic value of neurological symptoms in BM from melanoma.

Material and Methods

670 patients with newly diagnosed melanoma BM were identified from the Vienna Brain Metastasis Registry. We performed retrospective chart review and statistical outcome analyses.

Results

370/670 (55.2%) patients presented with neurological symptoms including neurological deficits (316/370; 85.4%), signs of increased intracranial pressure (126/370; 34.1%) and epileptic seizures (53/370; 14.3%). 57.6% (80/139) of patients with BRAF mutated melanoma presented with asymptomatic BM at diagnosis. Absence of neurological symptoms at BM diagnosis was associated with a longer median overall survival after time of BM diagnosis (7 vs. 5 months; p< 0.001; log-rank test). In multivariate analysis with the diagnosis-specific graded prognostic assessment (DS-GPA: HR:1.4; 95% CI, 1.25-1.48; p<0.001) and the graded prognostic assessment for melanoma using molecular markers (Melanoma-molGPA: HR:0.8; 95% CI, 0.66 -0.92; p<0.001), the presence of neurological symptoms (HR 0.8; 95% CI, 0.69 -0.96; p=0.003/ HR:0.6; 95% CI, 0.59-0.72; p<0.001) was found to be independently associated with survival prognosis from time of BM diagnosis respectively.

Conclusion:

Neurological symptoms at the time of BM diagnosis are an independent and strong prognostic factor in melanoma BM patients. Our results argue for the integration of neurological symptoms into the prognostic assessment of patients with BM from melanoma.

OS03.7.A Clinical characteristics, treatment and long-term outcome of patients with brain metastases from thyroid cancer - an analysis of the Vienna Brain Metastasis Registry

Background

The incidence of brain metastases (BM) in patients with thyroid cancer (TC) depends on the histological subtype. About 1% of patients with differentiated (DTC), 3% with medullary (MTC) and up to 10% with anaplastic thyroid cancer (ATC) develop BM. The diagnosis of BM drastically worsens the prognosis of TC. Given the rare incidence, little is known about the presentation and outcome of this cohort.

Material and Methods

Patients with a histologically verified diagnosis of TC and BM were identified from the Vienna Brain Metastasis Registry, a comprehensive database managed by the Division of Oncology, Medical University of Vienna, including patients with cerebral metastasis since 1990. Data were obtained from medical records comprising clinicopathological features, treatment, BM-specific characteristics and outcome.

Results

20/6074 patients included in the registry had a diagnosis of TC and radiologically verified BM. 13/20 (65%) were female and the median age at diagnosis of TC and manifestation of BM was 56 years (range 21-75) and 68 years (range 45-75), respectively. In terms of histology, 18/20 (90%) had DTC, one MTC and one ATC. Interestingly, 10/18 DTC presented with follicular histology which underlines the more aggressive course of this rare subtype. 6/20 (30%) had BM at primary diagnosis (DTC n=5, ATC n=1), while the remaining developed BM during follow-up. The median time to diagnosis of BM was 2.6 years for DTC (range 0-42), 22 years in the MTC patient and 2 months for ATC. Regarding BM-specific characteristics, all but one patient had symptoms due to BM (neurological deficits n=11, increased intracranial pressure n=5, seizures n=3). Most patients (13/20) had a singular BM, commonly located in the left hemisphere (8/13), and only one had more than three BMs. Upfront treatment for BM was local therapy (resection n=9, stereotactic radiosurgery n=7, whole brain radiotherapy n=3); one patient received supportive care only. The median overall survival (mOS) from diagnosis of TC was 6 years for DTC (range 2.5 months-42 years), 33 years for the MTC and 9 months for the ATC. The mOS from diagnosis of BM was 14 months for DTC (1.8 months-16 years), 22 years for the MTC and 3 months for the ATC.

Conclusion

Few patients with TC develop BM, which present commonly as single lesion. While in general BM constitute a poor prognostic factor, individual patients experience long-term survival following local therapy. More information about the optimal management of BM in TC is needed to enable guideline recommendations.

OS03.5.A Characterization of the inflammatory tumor microenvironment composition in solid cancer patients with brain metastases after progression to immune checkpoint inhibitor therapy

Background

Immunotherapy (IO) has changed the treatment landscape of metastatic cancer patients, however, treatment resistance is frequent. We aimed to characterize the inflammatory tumor microenvironment in brain metastases (BM) after IO to gain a deeper understanding of immunologic escape mechanisms.

Material and Methods

Solid cancer patients who had BM resection after IO progression (IO cohort) were retrospectively identified. We analyzed tumor-infiltrating immune cell subsets (CD3, CD8, CD45RO, FOXP3) and expression of immune checkpoint molecules (PD-L1, PD-1, LAG-3) by immunohistochemistry. A control cohort of BM tissue samples without prior IO served for comparison (no immunotherapy cohort, NIO).

Results

Twenty-eight IO patients (12/28, 42.9% females; 16/28, 57.1% males; median 61 years; 14/28, 50% lung cancer; 5/28, 17.9% melanoma; 4/28, 14.3% renal cell carcinoma; 1/28, 3.6% breast cancer; 4/28, 14.3% other cancer entities) and 57 NIO patients (28/57, 49.1% females; 29/57, 50.9% males; median 58 years; 35/57, 61.4% lung cancer; 9/57, 15.8% breast cancer; 4/57, 7.0% melanoma; 3/57, 5.3% renal cell carcinoma; 6/57, 10.5% other cancer entities) were included. IO patients had a median of one (range 0-4) systemic therapy line prior to IO. Median time from last IO application until BM resection was 5.6 months (range 0.2-49.8 months). Patients received a median number of 7 (range 1-56) IO applications (14/28, 50% PD-1-targeting IO; 8/28, 28.6% PD-L1; 2/28, 7.1% CTLA4; 4/28, 14.3% CTLA4+PD-1; 3/28, 10.7% IO+chemotherapy). No statistically significant differences in the densities of investigated TILs or PD-L1 expression between the IO and the NIO cohort were observed. Patients of the IO cohort showed higher PD-L1 expression compared to the NIO cohort (57.1 vs. 42.1%, Chi-square, p>0.05). Overall survival (OS) was similar in both cohorts, with a median OS of 11.0 months (range 5.0-17.0) in the IO cohort and 11.0 months (range 5.5-16.5) in the NIO cohort.

Conclusion

Our findings show an upregulation of PD-L1 in BM occurring after prior IO therapy in the absence of other overt changes in the inflammatory microenvironment. Ongoing analyses in this cohort are investigating possible molecular driver of resistance by analyzing DNA methylation profiles of pre-and post-IO tissue samples of the IO cohort to potentially gain insights on inflammatory IO resistance mechanisms in BM patients.

P14.03 Shifting trends and entity-specific aspects in patients with brain metastasis: real-life analysis from 6031 individuals over an observation period of 30 years

BACKGROUND

We aimed to investigate the changing clinical characteristics of patients with brain metastases (BM) over the last three decades as the foundation for modern BM specific clinical trial planning.

MATERIAL AND METHODS

6031 patients with newly diagnosed BM from different solid tumors treated between 1986–2020 were identified from the Vienna Brain Metastasis Registry.

RESULTS

The fraction of BM originating from the most common BM causing primary tumors (lung cancer, breast cancer and melanoma) was stable over the observation period from 1986–2020. BM from renal cell carcinoma, colorectal cancer and cancer of unknown primary (CUP) decreased over time (p<0.001). Synchronous diagnosis of BM and primary tumor was more frequently observed in lung cancer and CUP patients compared to breast cancer patients (p<0.001). An increasing fraction of patients presented with asymptomatic BM (1986–1999: 20.2% vs. 2010–2020: 30.4%; p<0.001), specifically in lung cancer (p<0.001), melanoma (p<0.001) and renal cell cancer (p=0.004). A decrease of neurosurgical procedures (1986–1999: 39.3% vs. 2010–2020: 20.4%) and an increase of radiation treatments (1986–1999: 56.5% vs. 2010–2020: 73.0%) and systemic therapies (1986–1999: 0.6% vs. 2010–2020: 2.4%; p<0.001) was observed. Furthermore, median overall survival significantly increased across entities (1986–1999: 5 months vs. 2010–2020: 7 months; p=0.001). Intracranial progression as the cause of death increased across entities (p< 0.001). The prognostic DS-GPA (Hazard ratio [HR] 1.42; p< 0.001) and the Lung-molGPA (HR 1.67; p<0.001) could be validated.

CONCLUSION

We observed changes of BM presentation and clinical parameters during the observation period depending on primary tumor origins. Future BM studies should follow an entity-specific approach and address the characteristics of modern BM cohorts.

Tumor mutational burden and immune infiltrates in renal cell carcinoma and matched brain metastases

BACKGROUND

Tumor mutational burden (TMB) and density of tumor-infiltrating lymphocytes (TIL) have been postulated as predictive biomarkers for immunotherapy. Therefore, we investigated the concordance of TMB and TIL of primary/extracranial renal cell carcinoma (RCC) specimens and matched brain metastases (BM).

PATIENTS AND METHODS

Twenty specimens from 10 patients were retrieved from the Vienna Brain Metastasis Registry (6/10 primary tumor, 4/10 lung metastasis, 10/10 matched BM). TMB was assessed using the TruSight Oncology 500 gene panel with libraries sequenced on a NextSeq instrument. TIL subsets (CD3+, CD8+, CD45RO+, FOXP3+, PD-L1+) were investigated using immunohistochemistry (Ventana Benchmark Ultra system) and automated tissue analysis (Definiens software).

RESULTS

No significant difference in TMB, CD3+, CD8+, CD45RO+, FOXP3+ or PD-L1+ expression was observed between extracranial and matched intracranial specimens (P > 0.05). Higher CD8+ TIL (P = 0.053) and CD45RO+ TIL (P = 0.030) densities in the primary tumor compared with the intracranial samples were observed in specimens collected after exposure to systemic treatment. Neither extracranial sample origin (lung metastasis versus primary RCC) nor extracranial disease status at BM diagnosis (progressive versus stable disease) were significantly associated with TMB or TIL densities in extracranial and intracranial samples (P > 0.05). No significant correlation was found between the median differences of TMB or TIL densities from extracranial to intracranial samples and BM-free survival.

CONCLUSION

The comparable immunological microenvironment of extra- and intracranial tumor samples in our study underscores the immunological activation also in BM from RCC, and therefore, supports the development of immune modulatory treatments also in patients with brain metastatic RCC.

P14.97 High risk of venous thromboembolism in patients with brain metastases from non-small cell lung cancer

BACKGROUND

Venous thromboembolism (VTE) is a common complication in patients with cancer. In general, patients with metastatic disease are at highest risk. Lung cancer belong to those tumor entities with a particularly high risk of VTE, ranging between 3–13.8%. However, little is known about the VTE rate in lung cancer patients with brain metastases.

MATERIAL AND METHODS

Our study was conducted in the framework of the Vienna Brain Metastasis Registry. Clinical data and VTE events during the course of the disease were recorded via retrospective chart review. In this analysis, non-small cell lung cancer (NSCLC) patients with a resection of brain metastases at the Medical University of Vienna between 2006 and 2010 were included.

RESULTS

In total, 69 NSCLC patients with brain metastases were analyzed. Overall, 69.6% (48/69) patients had an adenocarcinoma, 13% (9/69) a squamous cell carcinoma, 8.7% (6/69) a large cell carcinoma and 8.7% (6/69) other primary tumor histologies. After cancer diagnosis, 20.3% (14/69) patients developed VTE during the course of the disease. Of those, 85.7% (12/14) thromboembolic events occurred after the diagnosis of brain metastases.

CONCLUSION

Based on our data, patients with brain metastases from NSCLC have a very high VTE risk. Further investigations are needed in order to identify patients with distinct VTE risk profiles. Patients at high risk might potentially benefit from primary thromboprophylaxis over the high risk of intracerebral bleeding.

Brain metastases as first manifestation of advanced cancer: exploratory analysis of 459 patients at a tertiary care center

Symptomatic brain metastases (BM) are a frequent and late complication in cancer patients. However, a subgroup of cancer patients presents with BM as the first symptom of metastatic cancer. Here we aimed to analyze the clinical course and prognostic factors of this particular BM patient population. Patients presenting with newly diagnosed BM without a history of metastatic cancer were identified from the Vienna Brain Metastasis Registry. Clinical characteristics and overall survival were retrieved by chart review. 459/2419 (19.0%) BM patients presented with BM as first symptom of advanced cancer. In 374/459 (81.5%) patients, an extracranial primary tumor, most commonly lung cancer, could be identified within 3 months after BM diagnosis. In 85/459 (18.5%) patients no extracranial primary tumor could be identified despite comprehensive diagnostic workup within the first 3 months after diagnosis of BM. Survival of patients with identified extracranial tumor differed only numerically from patients with cancer of unknown primary (CUP), however patients receiving targeted therapy after molecular workup showed significantly enhanced survival (20 months vs. 7 months; p = 0.003; log rank test). The GPA score showed a statistically significant association with median overall survival times in the CUP BM patients (class I: 46 months; class II: 7 months; class III: 4 months; class IV: 2 months; p < 0.001; log rank test). The GPA score has a strong prognostic value in patients with CUP BM and may be useful for patient stratification in the clinical setting. Comprehensive diagnostic workup including advanced imaging techniques and molecular tissue analyses appears to benefit patients by directing specific molecular targeted therapies.

Decreased body mass index is associated with impaired survival in lung cancer patients with brain metastases: A retrospective analysis of 624 patients

Body mass index (BMI) is a prognostic factor in several cancer types. We investigated the prognostic role of BMI in a large patient cohort with newly diagnosed lung cancer brain metastases (BM) between 1990 and 2013. BMI at diagnosis of BM and graded prognostic assessment (GPA) were calculated. Definitions were underweight (BMI <18.50), weight within normal range (BMI 18.50-24.99) and overweight (BMI ≥ 25.00). A total of 624 patients (men 401/624 [64.3%]; women 223/624 [35.7%]; median age of 61 [range 33-88]) were analysed. Histology was non-small cell lung cancer in 417/622 (66.8%), small cell lung cancer (SCLC) in 205/624 (32.9%) and not otherwise specified in 2/624 (0.3%) patients. About 313/624 (50.2%) had normal BMI, 272/624 (43.5%) were overweight and 39/624 (6.3%) were underweight. Underweight patients had shorter median overall survival (3 months) compared to patients with normal BMI (7 months) and overweight (8 months; p < .001; log rank test). At multivariate analysis, higher GPA class (HR 1.430; 95% cumulative incidence, CI 1.279-1.598; p < .001; Cox regression model), SCLC histology (HR 1.310; 95% CI 1.101-1.558) and presence of underweight (HR 1.845; 95% CI 1.317-2.585; p = .014; Cox regression model) were independent prognostic factors. Underweight at diagnosis of BM in lung cancer is associated with an unfavourable prognosis.

Relative survival of patients with non-malignant central nervous system tumours: a descriptive study by the Austrian Brain Tumour Registry

BACKGROUND

Unlike malignant primary central nervous system (CNS) tumours outcome data on non-malignant CNS tumours are scarce. For patients diagnosed from 1996 to 2002 5-year relative survival of only 85.0% has been reported. We investigated this rate in a contemporary patient cohort to update information on survival.

METHODS

We followed a cohort of 3983 cases within the Austrian Brain Tumour Registry. All patients were newly diagnosed from 2005 to 2010 with a histologically confirmed non-malignant CNS tumour. Vital status, cause of death, and population life tables were obtained by 31 December 2011 to calculate relative survival.

RESULTS

Overall 5-year relative survival was 96.1% (95% CI 95.1-97.1%), being significantly lower in tumours of borderline (90.2%, 87.2-92.7%) than benign behaviour (97.4%, 96.3-98.3%). Benign tumour survival ranged from 86.8 for neurofibroma to 99.7% for Schwannoma; for borderline tumours survival rates varied from 83.2 for haemangiopericytoma to 98.4% for myxopapillary ependymoma. Cause of death was directly attributed to the CNS tumour in 39.6%, followed by other cancer (20.4%) and cardiovascular disease (15.8%).

CONCLUSION

The overall excess mortality in patients with non-malignant CNS tumours is 5.5%, indicating a significant improvement in survival over the last decade. Still, the remaining adverse impact on survival underpins the importance of systematic registration of these tumours.

Expression of hypoxia-inducible factor-1 alpha in oligodendrogliomas: its impact on prognosis and on neoangiogenesis

BACKGROUND

Hypoxia-inducible factor (HIF)1 alpha is considered to play a key role in the adaptation of cells to hypoxia by stimulating angiogenesis via regulation of vascular endothelial growth factor and by metabolic adaptation to O(2) deprivation.

METHODS

Expression of HIF-1 alpha protein and p53 was investigated by immunohistochemistry in 51 specimens of supratentorial pure oligodendrogliomas. Microvessels density (MVD) was determined by anti-CD34 immunostaining. The influence of HIF-1 alpha expression on survival was investigated using univariate and multivariate analysis.

RESULTS

Strong expression of HIF-1 alpha was observed in 12 (23.5%) specimens, moderate in 21 (41.2%) specimens, and weak in 8 (15.7%) cases, and no expression was found in 10 samples (19.6%). There was no correlation of HIF-1 alpha expression with histologic grading (P = 0.428, Mann-Whitney test). Hypoxia-inducible factor-1 alpha expression and MVD showed a strong correlation (P < 0.001, r = 0.735, Spearman coefficient of correlation). Overexpression of p53 was observed in only two cases. Patients with strong or moderate expression of HIF-1 alpha had a significantly shorter overall survival rate compared with those with low or no expression in univariate (P = 0.0434; log-rank test) and multivariate analysis (P = 0.0187).

CONCLUSIONS

Overexpression of HIF-1 alpha indicates a diminished prognosis in oligodendrogliomas, independent of p53 status. This finding may be explained by the strong vascularization of these tumors that prevents hypoxia and allows O(2) diffusion and henceforth tumor progression.

Expression of hypoxia-inducible factor-1 alpha in oligodendrogliomas: its impact on prognosis and on neoangiogenesis

BACKGROUND

Hypoxia-inducible factor (HIF)1 alpha is considered to play a key role in the adaptation of cells to hypoxia by stimulating angiogenesis via regulation of vascular endothelial growth factor and by metabolic adaptation to O(2) deprivation.

METHODS

Expression of HIF-1 alpha protein and p53 was investigated by immunohistochemistry in 51 specimens of supratentorial pure oligodendrogliomas. Microvessels density (MVD) was determined by anti-CD34 immunostaining. The influence of HIF-1 alpha expression on survival was investigated using univariate and multivariate analysis.

RESULTS

Strong expression of HIF-1 alpha was observed in 12 (23.5%) specimens, moderate in 21 (41.2%) specimens, and weak in 8 (15.7%) cases, and no expression was found in 10 samples (19.6%). There was no correlation of HIF-1 alpha expression with histologic grading (P = 0.428, Mann-Whitney test). Hypoxia-inducible factor-1 alpha expression and MVD showed a strong correlation (P < 0.001, r = 0.735, Spearman coefficient of correlation). Overexpression of p53 was observed in only two cases. Patients with strong or moderate expression of HIF-1 alpha had a significantly shorter overall survival rate compared with those with low or no expression in univariate (P = 0.0434; log-rank test) and multivariate analysis (P = 0.0187).

CONCLUSIONS

Overexpression of HIF-1 alpha indicates a diminished prognosis in oligodendrogliomas, independent of p53 status. This finding may be explained by the strong vascularization of these tumors that prevents hypoxia and allows O(2) diffusion and henceforth tumor progression.

Molecular mimicry in infectious encephalitis and neuritis: binding of antibodies against infectious agents on Western blots of human nervous tissue

OBJECTIVES

To study the occurrence of cross-reactivities of antibodies against infectious agents with human nervous tissue.

METHODS

Binding of 25 antibodies against 17 neurotropic pathogens comprising Borrelia burgdorferi, Toxoplasma gondii, and various DNA and RNA viruses to Western blots of human cortex and myelin from central and peripheral nervous system was investigated.

RESULTS

Fourteen of the 25 antibodies tested showed binding to Western blots of human nervous tissue, suggesting the presence of shared epitopes. Binding of 11 antibodies against 10 pathogens to cortex and/or myelin correlated with the tissue targeted by neuropathological lesions. Three antibodies did not show such correlation; 11 antibodies did not bind at all.

CONCLUSIONS

Our results suggest that shared epitopes between infectious agents and human nervous tissues are more common than previously expected. Thus, molecular mimicry should be considered more frequently as a possible pathogenetic mechanism, among others, inducing tissue damage in encephalitis and neuritis caused by various pathogens.

Antiglycosphingolipid immune responses in neurology. The Vienna experience with isotypes, subclasses, and disease

IgM, IgG, IgA, and IgG subclass anti-GM1, anti-GQ1b, and anti-asialo-GM1 (anti-GA1) antibodies, respectively, were investigated by ELISA in serum from neurological and other patients. Increased anti-GM1 occurred mostly in approximately 15-35% of the cases without statistical differences; high percentages were found in Guillain-Barré syndrome (GBS) preceded by gastrointestinal infection and multifocal motor neuropathy. Roughly, IgM anti-GM1 was most frequent; however, distinct IgG and IgA reactions were found i.a. in GBS. A particular IgM anti-mono- and disialoganglioside pattern occurred in a patient with sensorimotor neuropathy and paraproteinemia. Anti-GQ1b was elevated in all Miller-Fisher patients, with some prevalence of IgG2 among IgG subclasses. Cross-reactivity of anti-GQ1b was demonstrated with Campylobacter jejuni lipopolysaccharides. Increased anti-GM1 and/or anti-GA1 was more frequent in systemic lupus erythematosus with central nervous system involvement than without. Incidence of anti-GM1 and anti-GA1 in X-adrenoleukodystrophy was relatively high. Although anti-GSL antibodies seem to have limited diagnostic value, studies of isotypes, subclass patterns, and cross-reactivities may lead to further insight into the origin of (auto) immune responses and their immunepathogenetic role in disease.

[Cerebrospinal fluid diagnosis of Creutzfeldt-Jakob disease]

Diagnosis of Creutzfeldt-Jakob disease (CJD) at lifetime according to the international diagnostic criteria may be greatly improved by the additional assay of 14-3-3 protein in cerebrospinal fluid (CSF). Occurrence of 14-3-3 protein in CSF may be observed in etiologically different conditions of brain damage, but confers high diagnostic specificity in cases of suspected CJD based on the diagnostic criteria. We investigated the occurrence of 14-3-3 protein in CSF of 20 patients with an accompanying diagnosis "suspected CJD", of whom 5 cases had to be classified as neither probable nor possible CJD according to the international diagnostic criteria, as well as in 18 control cases with diseases other than CJD. Assay of 14-3-3 comprised SDS-PAGE, western blot, immunostaining with specific antibody, and luminiscence detection. With regard to case histories at the end of our study, 8 definitive and probable CJD cases were 14-3-3 positive and 2 possible CJD cases 14-3-3 negative. Of the 10 cases with final diagnosis other than CJD, 8 cases (in part with manifest or suspected brain damage; one case with hemorrhagic CSF) were 14-3-3 positive. Of the 18 controls with diseases other than CJD, 6 patients, characterized by brain tissue lesions or meningitis, respectively, were found to be 14-3-3 positive. Our observations, the first in Austria and on a limited number of patients yet, are in accordance with previous reports in the literature and further support the use of the 14-3-3 protein assay in CSF as a diagnostic tool for CJD, provided that probands had been pre-evaluated positively by the international diagnostic criteria for CJD.