Combined immunotherapy in melanoma patients with brain metastases: A multicenter international study

Stereotactic Radiosurgery Dose Reduction for Melanoma Brain Metastases Patients on Immunotherapy or Target Therapy: A Single-Center Experience

BACKGROUND AND OBJECTIVES

Better local control but higher rates of adverse radiation events (ARE) have been reported when combining American Society for Radiation Oncology (ASTRO)-guideline-suggested dose (SD) stereotactic radiosurgery (SRS) with immunotherapy or targeted therapy for melanoma brain metastases. The objective of this study is to explore the efficacy and safety of lower prescription doses compared with ASTRO guidelines for single-fraction SRS for patients with melanoma metastases who are concurrently receiving immunotherapy or targeted therapy.

METHODS

We conducted a retrospective, single-center study on 194 patients who underwent SRS between 2009 and 2022. After propensity score matching, 71 patients with 292 metastases were included in the ASTRO-SD (20-24 Gy for <2 cm, 18 Gy for ≥2 to <3 cm) group and 33 patients with 292 metastases in the reduced dose (RD, <20 Gy for <2 cm, <18 Gy for ≥2 to <3 cm) group.

RESULTS

The median diameter (5.4 vs 5.2 mm, P = .6), prescription volume (0.2 vs 0.2 cm 3 , P = .2), and radiographic follow-up (11 vs 12 months, P = .2) were similar in the 2 groups. The cumulative incidence of progressing metastases was significantly higher in the SD compared with the RD group ( P = .018). Higher prescription volumes and ASTRO-suggested radiation doses were associated with local progression in multivariable analysis. Radiographic AREs were significantly more common in the SD compared with the RD group (8.6% vs 3.1%, P = .005). BRAF and other tyrosine kinase inhibitors' concurrent use, higher prescription volumes, and ASTRO-suggested radiation doses were associated with an increased risk of radiographic ARE.

CONCLUSION

This study provides evidence that RD SRS could offer reduced toxicity rates, while maintaining high local control as compared with the current guideline-SDs for the treatment of melanoma brain metastases.

Improved Survival and Prognostication in Melanoma Patients With Brain Metastases: An Update of the Melanoma Graded Prognostic Assessment

PURPOSE

Survival for patients with melanoma has recently improved. The propensity of melanoma to metastasize to the brain remains a common and serious feature of this disease. The purposes of this study were to evaluate prognostic factors for patients with newly diagnosed melanoma brain metastases (MBMs) in a large cohort treated with modern multimodal therapies, compare those results with those in prior eras, and update the Melanoma Graded Prognostic Assessment (GPA).

METHODS

Univariable and multivariable (MVA) analyses of prognostic factors and treatments associated with survival were performed on 1,796 patients with newly diagnosed MBM treated between January 01, 2015, and December 31, 2021, using a multi-institutional retrospective database. Multiple imputation was used to address missingness of potential predictors. Significant variables in combined MVA were used to update the Melanoma GPA. Comparisons were made with legacy cohorts.

RESULTS

Median survivals for cohorts A (1985-2007, n = 481), B (2006-2015, n = 823), and C (2015-2021, n = 1,796) were 6.7, 9.8, and 16.6 months and median follow-up times were 40.1, 43.6, and 48.8 months, respectively. In combined MVA, significant prognostic factors for survival were higher Karnofsky Performance Status, fewer MBMs, absence of extracranial metastases, lower serum lactate dehydrogenase, and no immunotherapy before MBM. These factors were incorporated into the updated Melanoma GPA. The combined median and 3-year survivals for patients with GPA 0-1, 1.5-2, and 2.5-4.0 were 5.4, 13.2, and 43.2 months and 12.4%, 28.8%, and 51.6%, respectively.

CONCLUSION

Prognostic factors have changed and survival has improved for patients with MBM but varies widely by GPA. The updated Melanoma GPA calculator (BrainMetGPA), available free online, can be used to estimate survival, individualize treatment, stratify clinical trials, guide surveillance, and augment clinical trial eligibility. Multidisciplinary treatment is essential. Trials are needed to elucidate the optimal sequencing of various therapeutic modalities.

Timing of brain metastases in relation to outcome during first-line ipilimumab plus nivolumab therapy for metastatic melanoma in a community oncology practice

PURPOSE

Patients with metastatic melanoma frequently develop brain metastases. Due to recent advances in melanoma therapy, we evaluated the timing of brain metastases diagnosis in relation to outcome during melanoma immunotherapy.

METHODS

Patients who received 1st -line treatment with ipilimumab plus nivolumab for metastatic melanoma were identified via a database search. Patient characteristics and outcomes were recorded.

RESULTS

Of 73 patients that met study criteria, 20 patients developed brain metastases (27.4%). Of these 20 patients, 14 had brain metastases at diagnosis of metastatic disease, Only 6 progressed in the brain following immunotherapy. All but one patient with brain metastases at diagnosis were symptomatic. Following immunotherapy, 4/15 (all with BRAF V600E mutations) achieved complete remissions and prolonged survival. Each of these patients was able to undergo elective treatment discontinuation. One additional patient developed stable disease. Delayed brain metastases proved to be infrequent (6/59 patients). Delayed brain metastases were always diagnosed within the first 15 months of treatment. Five of these 6 patients died, with a median progression-free survival of only 2.1 months.

CONCLUSION

Brain metastases frequently complicated the course of metastatic melanoma. Patients with symptomatic brain metastases at diagnosis had a potential for durable remissions following multidisciplinary treatment, particularly if a BRAF V600E mutation was present. This included 2 of 10 patients who were on steroid treatment prior to the start of immunotherapy. Treatment with combination immunotherapy seemed to reduce the development of subsequent brain metastases. Patients who developed delayed brain metastases had a very poor outlook, despite attempted salvage therapy.

Current Treatment Paradigms for Advanced Melanoma with Brain Metastases

The therapeutic management of melanoma brain metastases has undergone a profound revolution during recent decades. Optimal integration of systemic therapies with local treatments seems to represent the strategy to pursue in order to maximize clinical outcomes, stressing the need for real multidisciplinary care in this setting of patients. However, the current approach in the clinics does not necessarily reflect what the current guidelines state, and several pending issues are present, from the ideal therapeutic sequence between stereotactic radiosurgery (SRS) and drug administration to the current role of surgery and whole brain radiotherapy (WBRT), all of which need to be addressed. This narrative review aims to provide practical help for navigating the current controversies, with an eye towards possible future advancements in the field, which could help to obtain a comprehensive molecular characterization of the tumor and a more personalized patient-centered therapeutic approach.

Progress in immunotherapy for brain metastatic melanoma

Melanoma is highly aggressive, with brain metastasis being a significant contributor to poor outcomes. Immunotherapy has emerged as a crucial treatment modality for melanoma, particularly for addressing brain metastases. This review explores recent developments in immunotherapy for patients with melanoma brain metastasis, with such treatments encompassing immune checkpoint inhibitors and various immunotherapy combination approaches, such as dual immunotherapy, immunotherapy combined with chemotherapy, immunotherapy combined with targeted drugs, and immunotherapy combined with radiotherapy. This article also discusses existing treatment obstacles and potential future avenues for research and clinical practice.

European consensus-based interdisciplinary guideline for melanoma. Part 2: Treatment - Update 2024

A unique collaboration of multi-disciplinary experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF), and the European Organization of Research and Treatment of Cancer (EORTC) was formed to make recommendations on cutaneous melanoma diagnosis and treatment, based on systematic literature reviews and the experts' experience. Cutaneous melanomas are excised with one to two-centimeter safety margins. For a correct stage classification and treatment decision, a sentinel lymph node biopsy shall be offered in patients with tumor thickness ≥ 1.0 mm or ≥ 0.8 mm with additional histological risk factors, although there is as yet no clear survival benefit for this approach. Therapeutic decisions should be primarily made by an interdisciplinary oncology team ("Tumor Board"). Adjuvant therapies can be proposed in completely resected stage IIB-IV. In stage II only PD-1 inhibitors are approved. In stage III anti-PD-1 therapy or dabrafenib plus trametinib for patients with BRAFV600 mutated melanoma can be discussed. In resected stage IV, nivolumab can be offered, as well as ipilimumab and nivolumab, in selected, high-risk patients. In patients with clinically detected macroscopic, resectable disease, neoadjuvant therapy with ipilimumab plus nivolumab followed complete surgical resection and adjuvant therapy according to pathological response and BRAF status can be offered. Neoadjuvant therapy with pembrolizumab followed by complete surgical resection and adjuvant pembrolizumab is also recommended. For patients with disease recurrence after (neo) adjuvant therapy, further treatment should consider the type of (neo) adjuvant therapy received as well as the time of recurrence, i.e., on or off therapy. In patients with irresectable stage III/IV disease systemic treatment is always indicated. For first line treatment PD-1 antibodies alone or in combination with CTLA-4 or LAG-3 antibodies shall be considered. In stage IV melanoma with a BRAFV600 mutation, first-line therapy with BRAF/MEK inhibitors can be offered as an alternative to immunotherapy, in selected cases. In patients with primary resistance to immunotherapy and harboring a BRAFV600 mutation, this therapy shall be offered as second line. Other second line therapies include therapy with tumor infiltrating lymphocytes and combinations of immune checkpoint inhibitors not used in first line. This guideline is valid until the end of 2026.

The Role of Radiotherapy in the Management of Melanoma Brain Metastases: An Overview

OPINION STATEMENT

Clinical management of melanoma brain metastases is complex and requires multidisciplinary approach. With close collaboration between neurosurgeons, radiation oncologists and medical oncologists, melanoma patients with brain are offered different treatment modalities: surgery, radiation therapy, systemic therapy or combined treatments. Radiation therapy (whole brain radiotherapy- WBRT and stereotactic radiosurgery- SRS) is an integral part of treating melanoma brain metastases. Use of immunotherapy (checkpoint inhibitors) and targeted therapy (BRAF/MEK inhibitors) significantly changed the outcome in patients with melanoma metastases. Currently, ipilimumab and nivolumab (COMBO) is the preferred first-line systemic therapy for all patients with asymptomatic brain metastases, regardless of BRAF status (BRAF wild-type and BRAF-mutated). Although at the moment there is no consensus on the concomitant use of SRS and COMBO, results from clinical trials suggest that this combined treatment modality should be considered the standard of care for melanoma patients with brain metastases. However, further clinical research is required to define optimal treatment modalities for routine management of melanoma brain lesions.

Targeting anticancer immunity in melanoma tumour microenvironment: unleashing the potential of adjuvants, drugs, and phytochemicals

Melanoma poses a challenge in oncology because of its aggressive nature and limited treatment modalities. The tumour microenvironment (TME) in melanoma contains unique properties such as an immunosuppressive and high-density environment, unusual vasculature, and a high number of stromal and immunosuppressive cells. In recent years, numerous experiments have focused on boosting the immune system to effectively remove malignant cells. Adjuvants, consisting of phytochemicals, toll-like receptor (TLR) agonists, and cytokines, have shown encouraging results in triggering antitumor immunity and augmenting the therapeutic effectiveness of anticancer therapy. These adjuvants can stimulate the maturation of dendritic cells (DCs) and infiltration of cytotoxic CD8+ T lymphocytes (CTLs). Furthermore, nanocarriers can help to deliver immunomodulators and antigens directly to the tumour stroma, thereby improving their efficacy against malignant cells. The remodelling of melanoma TME utilising phytochemicals, agonists, and other adjuvants can be combined with current modalities for improving therapy outcomes. This review article explores the potential of adjuvants, drugs, and their nanoformulations in enhancing the anticancer potency of macrophages, CTLs, and natural killer (NK) cells. Additionally, the capacity of these agents to repress the function of immunosuppressive components of melanoma TME, such as immunosuppressive subsets of macrophages, stromal and myeloid cells will be discussed.

Anti-PD-1/PD-L1 inhibitor therapy for melanoma brain metastases: a systematic review and meta-analysis

Melanoma brain metastases present a major challenge in cancer treatment and reduce overall survival despite advances in managing primary melanoma. Immune checkpoint inhibitors (ICIs) that target PD-1/PD-L1 pathways have shown promise in treating advanced melanoma, but their efficacy for melanoma brain metastases is debated. This systematic review and meta-analysis summarize evidence on anti-PD-1/PD-L1 inhibitors for melanoma brain metastases. This systematic review and meta-analysis followed PRISMA guidelines. PICO criteria targeted melanoma brain metastasis patients treated with PD-1/PD-L1 inhibitors, assessing overall survival, progression-free survival, and complications. Inclusion criteria were English studies on humans using PD-1/PD-L1 inhibitors for melanoma brain metastases with > 10 patients. A total of 22 trials involving 1523 melanoma brain metastase patients treated with anti-PD-1/PD-L1 inhibitors were thoroughly analyzed. Our findings show the 6-month OS rate of 0.75 [95%CI:0.67-0.84], the 6-months PFS rate of 0.42 [95%CI:0.31-0.52], the 1-year OS rate of 0.63 [95%CI:0.52-0.74], the 1-year PFS rate was 0.45 [95%CI:0.32-0.58], the 18-months OS rate of 0.52 [95%CI:0.37-0.67], the 2-year OS rate of 50% [95% CI: (34%-65%)], the 2 year PFS rate of 0.36 (95%CI:0.23-0.50), the 3-year OS rate of 0.42 (95%CI:0.17-0.67), the 4-year PFS rate of 0.35 [95%CI:0.08-0.61], the 4-year OS rate of 0.29 [95%CI:0.01-0.56], the 5-year OS rate of 0.29 (95%CI:0.09-0.50), and the 5-year PFS rate of 0.11 (95%CI:0.03-0.19). The combined disease stability rate was 0.13 [95%CI:0.05-0.20], the progressive disease rate was 0.49 [95%CI:0.37-0.62], the partial response rate was 0.14 [95%CI:0.07-0.20], the object response rate was 0.35 [95%CI:0.24-0.46], and the complete response rate was 0.22 [95%CI:0.12-0.32]. In conclusion, our meta-analysis provides compelling evidence supporting the efficacy of PD-1/PD-L1 inhibitors in patients with melanoma brain tumors, as evidenced by favorable survival outcomes and disease control rates.

Personalized identification and characterization of genome-wide gene expression differences between patient-matched intracranial and extracranial melanoma metastasis pairs

Melanoma is the most serious type of skin cancer that frequently spreads to other organs of the human body. Especially melanoma metastases to the brain (intracranial metastases) are hard to treat and a major cause of death of melanoma patients. Little is known about molecular alterations and altered mechanisms that distinguish intra- from extracranial melanoma metastases. So far, almost all existing studies compared intracranial metastases from one set of patients to extracranial metastases of an another set of melanoma patients. This neglects the important facts that each melanoma is highly individual and that intra- and extracranial melanoma metastases from the same patient are more similar to each other than to melanoma metastases from other patients in the same organ. To overcome this, we compared the gene expression profiles of 16 intracranial metastases to their corresponding 21 patient-matched extracranial metastases in a personalized way using a three-state Hidden Markov Model (HMM) to identify altered genes for each individual metastasis pair. This enabled three major findings by considering the predicted gene expression alterations across all patients: (i) most frequently altered pathways include cytokine-receptor interaction, calcium signaling, ECM-receptor interaction, cAMP signaling, Jak-STAT and PI3K/Akt signaling, (ii) immune-relevant signaling pathway genes were downregulated in intracranial metastases, and (iii) intracranial metastases were associated with a brain-like phenotype gene expression program. Further, the integration of all differentially expressed genes across the patient-matched melanoma metastasis pairs led to a set of 103 genes that were consistently down- or up-regulated in at least 11 of the 16 of the patients. This set of genes contained many genes involved in the regulation of immune responses, cell growth, cellular signaling and transport processes. An analysis of these genes in the TCGA melanoma cohort showed that the expression behavior of 11 genes was significantly associated with survival. Moreover, a comparison of the 103 genes to three closely related melanoma metastasis studies revealed a core set of eight genes that were consistently down- or upregulated in intra- compared to extracranial metastases in at least two of the three related studies (down: CILP, DPT, FGF7, LAMP3, MEOX2, TMEM119; up: GLDN, PMP2) including FGF7 that was also significantly associated with survival. Our findings contribute to a better characterization of genes and pathways that distinguish intra- from extracranial melanoma metastasis and provide important hints for future experimental studies to identify potential targets for new therapeutic approaches.