Brain Metastases: A Society for Neuro-Oncology (SNO) Consensus Review on Current Management and Future Directions

Brain metastases occur commonly in patients with advanced solid malignancies. Yet, less is known about brain metastases than cancer-related entities of similar incidence. Advances in oncologic care have heightened the importance of intracranial management. Here, in this consensus review supported by the Society for Neuro-Oncology (SNO), we review the landscape of brain metastases with particular attention to management approaches and ongoing efforts with potential to shape future paradigms of care. Each coauthor carried an area of expertise within the field of brain metastases and initially composed, edited, or reviewed their specific subsection of interest. After each subsection was accordingly written, multiple drafts of the manuscript were circulated to the entire list of authors for group discussion and feedback. The hope is that the these consensus guidelines will accelerate progress in the understanding and management of patients with brain metastases, and highlight key areas in need of further exploration that will lead to dedicated trials and other research investigations designed to advance the field

Incidence of brain metastases in patients with early HER2-positive breast cancer receiving neoadjuvant chemotherapy with trastuzumab and pertuzumab

The addition of pertuzumab (P) to trastuzumab (H) and neoadjuvant chemotherapy (NAC) has decreased the risk of distant recurrence in early stage HER2-positive breast cancer. The incidence of brain metastases (BM) in patients who achieved pathological complete response (pCR) versus those who do not is unknown. In this study, we sought the incidence of BM in patients receiving HP-containing NAC as well as survival outcome. We reviewed the medical records of 526 early stage HER2-positive patients treated with an HP-based regimen at Memorial Sloan Kettering Cancer Center (MSKCC), between September 1, 2013 to November 1, 2019. The primary endpoint was to estimate the cumulative incidence of BM in pCR versus non-pCR patients; secondary endpoints included disease free-survival (DFS) and overall survival (OS). After a median follow-up of 3.2 years, 7 out of 286 patients with pCR had a BM while 5 out of 240 non-pCR patients had a BM. The 3-year DFS was significantly higher in the pCR group compared to non-pCR group (95% vs 91 %, p = 0.03) and the same trend was observed for overall survival. In our cohort, despite the better survival outcomes of patients who achieved pCR, we did not observe appreciable differences in the incidence of BM by pCR/non-pCR status. This finding suggests that the BM incidence could not be associated with pCR. Future trials with new small molecules able to cross the blood brain barrier should use more specific biomarkers rather than pCR for patients' selection

Melanoma Central Nervous System Metastases: An Update to Approaches, Challenges, and Opportunities

Brain metastases are the most common brain malignancy. This review discusses the studies presented at the third annual meeting of the Melanoma Research Foundation in the context of other recent reports on the biology and treatment of melanoma brain metastases (MBM). Although symptomatic MBM patients were historically excluded from immunotherapy trials, efforts from clinicians and patient advocates have resulted in more inclusive and even dedicated clinical trials for MBM patients. The results of checkpoint inhibitor trials were discussed in conversation with current standards of care for MBM patients, including steroids, radiotherapy, and targeted therapy. Advances in the basic scientific understanding of MBM, including the role of astrocytes and metabolic adaptations to the brain microenvironment, are exposing new vulnerabilities which could be exploited for therapeutic purposes. Technical advances including single-cell omics and multiplex imaging are expanding our understanding of the MBM ecosystem and its response to therapy. This unprecedented level of spatial and temporal resolution is expected to dramatically advance the field in the coming years and render novel treatment approaches that might improve MBM patient outcomes

Targeted therapy in the treatment of malignant gliomas

Rimas V Lukas1, Adrienne Boire2, M Kelly Nicholas1,2 1Department of Neurology; 2Department of Medicine, University of Chicago, Chicago, IL, USAAbstract: Malignant gliomas are invasive tumors with the potential to progress through current available therapies. These tumors are characterized by a number of abnormalities in molecular signaling that play roles in tumorigenesis, spread, and survival. These pathways are being actively investigated in both the pre-clinical and clinical settings as potential targets in the treatment of malignant gliomas. We will review many of the therapies that target the cancer cell, including the epidermal growth factor receptor, mammalian target of rapamycin, histone deacetylase, and farnesyl transferase. In addition, we will discuss strategies that target the extracellular matrix in which these cells reside as well as angiogenesis, a process emerging as central to tumor development and growth. Finally, we will briefly touch on the role of neural stem cells as both potential targets as well as delivery vectors for other therapies. Interdependence between these varied pathways, both in maintaining health and in causing disease, is clear. Thus, attempts to easily classify some targeted therapies are problematic.Keywords: glioma, EGFR, mTOR, HDAC, Ras, angiogenesi

Brain metastasis.

Brain metastasis, which commonly arises in patients with lung cancer, breast cancer and melanoma, is associated with poor survival outcomes and poses distinct clinical challenges. The brain microenvironment, with its unique cell types, anatomical structures, metabolic constraints and immune environment, differs drastically from microenvironments of extracranial lesions, imposing a distinct and profound selective pressure on tumour cells that, in turn, shapes the metastatic process and therapeutic responses. Accordingly, the study of brain metastasis could uncover new therapeutic targets and identify novel treatment approaches to address the unmet clinical need. Moreover, such efforts could provide insight into the biology of primary brain tumours, which face similar challenges to brain metastases of extracranial origin, and vice versa. However, the paucity of robust preclinical models of brain metastasis has severely limited such investigations, underscoring the importance of developing improved experimental models that holistically encompass the metastatic cascade and/or brain microenvironment. In this Viewpoint, we asked four leading experts to provide their opinions on these important aspects of brain metastasis biology and management.M.V. acknowledges support from the Ministry of Economy and Competitiveness (MINECO) grant MINECO-Retos SAF2017-89643-R, the Bristol-Myers Squibb-Melanoma Research Alliance Young Investigator Award 2017 (498103), the Beug Foundation's Prize for Metastasis Research 2017, Fundacion Ramon Areces (CIVP19S8163), Worldwide Cancer Research (19-0177), Horizon 2020 Funding and Emerging Technologies (FET) Open (828972), the Clinic and Laboratory Integration Program Cancer Research Institute (CRI) Award 2018 (54545) and Spanish Association Against Cancer (AECC) Coordinated Translational Groups 2017 (GCTRA16015SEOA). M.V. is a Ramon y Cajal Investigator (RYC-2013-13365) and a member of the European Molecular Biology Organization Young Investigator Programme (EMBO YIP; 4053). L.G. is supported by CIHR Operating Grant PJT-162234, Terry Fox Research Institute grant TFRI1087, Canadian Cancer Society Research Institute CCS#705799, the Cancer Research Society and the C17 Research Network.S

Tumour Dormancy and Reawakening: Opportunities and Challenges

Tumour dormancy presents challenges for clinical control and opportunities for scientific discovery. Current pictures of the mechanisms of tumour dormancy and reawakening remain incomplete. The Cancer Research UK's third Marshall Symposium explored tumour dormancy and reawakening in all their forms. In this forum article, we highlight the key challenges and opportunities discussed at this symposium