Adjuvant systemic therapy in high-risk melanoma

Prognostic and Predictive Significance of Ki67 in Primary Non-metastatic or Recurrent Acral Melanoma: Evidence from a Multicenter Retrospective Study

BACKGROUND

The purpose of this work was to investigate the prognostic significance of Ki67 in acral melanoma (AM).

PATIENTS AND METHODS

Ki67 values in primary lesions (pKi67) of 481 patients with primary non-metastatic AM (primary cohort) from three tertiary hospitals and in recurrent lesions (rKi67) of 97 patients (recurrent cohort) were recorded. The associations of p/rKi67 with clinicopathological features and prognosis were analyzed.

RESULTS

In the primary cohort, high pKi67 group tended to have more ulceration, pT4, lymph node metastasis (LNM), nodal macrometastases, and recurrence (all P < 0.05). Logistic regression analysis revealed that pKi67 was significantly associated with pT4 and LNM (P = 0.004 and 0.027, respectively). Furthermore, both 5-year overall survival (OS) and recurrence-free survival (RFS) rates in high pKi67 group were significantly worse than those in moderate and low pKi67 groups (OS 47.8% versus 55.7 versus 76.8%, P = 0.002; RFS: 27.1 versus 42.8 versus 61.8%, P < 0.001). Similarly, in the recurrent cohort, the 5-year survival after recurrence (SAR) rates in high rKi67 group was significantly worse than those in moderate and low rKi67 groups (31.7 versus 47.4 versus 75%; P = 0.026). Stratified analysis also indicated a significant survival difference among pKi67 groups within various subgroups. Most importantly, multivariate Cox analysis demonstrated that pKi67 could be independently associated with OS and RFS, as well as rKi67 for SAR (all P < 0.05).

CONCLUSIONS

A high Ki67 value was significantly associated with adverse pathological and prognostic features in both primary and recurrent AM cohorts. Ki67 should be routinely evaluated to guide risk stratification and prognostic prediction.

Interferon-gamma signature as prognostic and predictive marker in macroscopic stage III melanoma

BACKGROUND

A substantial proportion of patients with macroscopic stage III melanoma do not benefit sufficiently from adjuvant anti-PD-1 therapy, as they either recur despite therapy or would never have recurred. To better inform adjuvant treatment selection, we have performed translational analyses to identify prognostic and predictive biomarkers.

PATIENTS AND METHODS

Two cohorts of patients with macroscopic stage III melanoma from an ongoing biobank study were included. Clinical data were compared between an observation cohort (cohort 1) and an adjuvant intention cohort (cohort 2). RNA sequencing for translational analyses was performed and treatment subgroups (cohort 1A and cohort 2A) were compared for possible biomarkers, using a cut-off based on the treatment-naïve patients. In addition, two validation cohorts (Melanoma Institute Australia (MIA) and University Medical Centre Utrecht (UMCU)) were obtained.

RESULTS

After a median follow-up of 26 months of the 98 patients in our discovery set, median recurrence-free survival (RFS) was significantly longer for the adjuvant intention cohort (cohort 2, n=49) versus the observation cohort (cohort 1, n=49). Median overall survival was not reached for either cohort, nor significantly different. In observation cohort 1A (n=24), RFS was significantly longer for patients with high interferon-gamma (IFNγ) score (p=0.002); for adjuvant patients of cohort 2A (n=24), a similar trend was observed (p=0.086). Patients with high B cell score had a longer RFS in cohort 1A, but no difference was seen in cohort 2A. The B cell score based on RNA correlated with CD20+ cells in tumor area but was not independent from the IFNγ score. In the MIA validation cohort (n=44), longer RFS was observed for patients with high IFNγ score compared with low IFNγ score (p=0.046), no difference in RFS was observed according to the B cell score. In both the observation (n=11) and the adjuvant (n=11) UMCU validation cohorts, no difference in RFS was seen for IFNγ and B cell.

CONCLUSIONS

IFNγ has shown to be a prognostic marker in both patients who were and were not treated with adjuvant therapy. B cell score was prognostic but did not improve accuracy over IFNγ. Our study confirmed RFS benefit of adjuvant anti-PD-1 for patients with macroscopic stage III melanoma.

HLA-DRB1: A new potential prognostic factor and therapeutic target of cutaneous melanoma and an indicator of tumor microenvironment remodeling

Cutaneous melanoma (CM) is the most common skin cancer and one of the most aggressive cancers and its incidence has risen dramatically over the past few decades. The tumor microenvironment (TME) plays a crucial role in the occurrence and development of cutaneous melanoma. Nevertheless, the dynamics modulation of the immune and stromal components in the TME is not fully understood. In this study, 471 CM samples were obtained from TCGA database, and the ratio of tumor-infiltrating immune cells (TICs) in the TME were estimated using the ESTIMATE algorithms and CIBERSORT computational method. The differently expressed genes (DEGs) were applied to GO and KEGG function enrichment analysis, establishment of protein-protein interaction (PPI) network and univariate Cox regression analysis. Subsequently, we identified a predictive factor: HLA-DRB1 (major histocompatibility complex, class II, DR beta 1) by the intersection analysis of the hub genes of PPI network and the genes associated with the prognosis of the CM patients obtained by univariate Cox regression analysis. Correlation analysis and survival analysis showed that the expression level of HLA-DRB1 was negatively correlated with the Stage of the patients while positively correlated with the survival, prognosis and TME of melanoma. The GEPIA web server and the representative immunohistochemical images of HLA-DRB1 in the normal skin tissue and melanoma tissue from the Human Protein Atlas (HPA) database were applied to validate the expression level of HLA-DRB1. CIBERSORT analysis for the ratio of TICs indicated that 9 types of TICs were positively correlated with the expression level of HLA-DRB1 and only 4 types of TICs were negatively correlated with the expression level of HLA-DRB1. These results suggested that the expression level of HLA-DRB1 may be related to the immune activity of the TME and may affect the prognosis of CM patients by changing the status of the TME.

Need to restage Korean melanoma patients following publication of the 8th edition of the American Joint Committee on Cancer staging manual

BACKGROUND

The tumor, nodes and metastasis (TNM) classification and stage grouping have been updated in the 8th edition of the American Joint Committee on Cancer (AJCC) melanoma staging manual. However, restaging all the previous cases are not recommended.

AIMS

The aims of the study were to investigate the necessity of restaging Korean melanoma patients staged by the previous edition of the AJCC manual.

METHODS

Differences in the staging criteria of the 7th and 8th editions of the AJCC manual were identified. The staging of 276 primary melanomas from January 2011 to December 2018 was classified by both 7th and 8th editions of the manual and their differences were compared.

RESULTS

Staging by 7th and 8th edition of the AJCC manual differed in 64 cases (23.2%). The pathological prognostic staging changed in 35 (12.7%), and 29 (10.5%) had changes in only TNM classification but not the pathological staging. None of the patients needed additional sentinel lymph node biopsy or systemic treatment as a result of restaging. Additional counseling was needed for the patients, because melanoma-specific survival was increased in the 8th edition.

LIMITATIONS

This is a retrospective study with relatively small number of patients at a single tertiary center in Korea.

CONCLUSION

Assessment of the need for additional sentinel lymph node biopsy or systemic treatment is recommended because of the latest changes in the AJCC melanoma staging manual. Although the restaging of previously staged melanomas is not significantly needed in our patients, still the differences in TNM classification and/or pathological prognostic staging suggest the need to separately recognize the patients previously staged by 7th edition and recently staged by 8th edition. Careful counseling about melanoma-specific survival is needed for Asian patients.

Characterization and Clinical Utility of BRAFV600 Mutation Detection Using Cell-Free DNA in Patients with Advanced Melanoma

Simple Summary

The choice of cancer drug(s) for the treatment of advanced melanoma is based on the types of gene alterations that are present in the patient’s tumor(s). Sometimes, the tumor sample that is obtained from surgery may be degraded, and the test does not provide a reliable result, leading to the selection of the wrong treatment, and, consequently, poor outcomes for the patient. Surgery to obtain fresh tumor samples is inconvenient. In recent years, scientists have learned that fragments of genes from dying cells, including tumors, are constantly being released into the blood. This study shows that the presence of altered genes can be reliably determined using easy-to-obtain blood samples. The study also shows that, while there is a small rate of error with the commonly used tests based on the tumor tissue sample, retests using blood samples may be a less invasive and rapid alternative for identifying the BRAF mutation status and selecting the right treatment for these patients.

Abstract

Tissue-based tests for BRAF^V600 mutation-positive melanoma involve invasive biopsy procedures, and can lead to an erroneous diagnosis when the tumor samples degrade. Herein, we explored a minimally invasive, cell-free deoxyribonucleic acid (cfDNA)-based platform, to retest patients for BRAF^V600 mutations. This phase 2 study enrolled adult patients with unresectable/metastatic melanoma. A prescreening testing phase evaluated the concordance between a prior tissue-based BRAF^V600 mutation test result and a subsequent plasma cfDNA-based test result. A treatment phase evaluated the patients who were confirmed as BRAF^V600 mutation-positive, and were treated with cobimetinib plus vemurafenib. It was found that 35/54 patients (64.8%) with a mutant BRAF status by prior tissue test had a positive BRAF^V600 mutation with the cfDNA test. Further, 7/118 patients (5.9%) with a wild-type BRAF status had a positive BRAF^V600 mutation cfDNA test; tissue retests on archival samples confirmed BRAF^V600 mutation positivity in 5/7 patients (71.4%). One of these patients received BRAF pathway-targeted therapy (cobimetinib plus vemurafenib), and had progression-free survival commensurate with previous experience. In the overall cobimetinib plus vemurafenib-treated population, 29/36 patients (80.6%) had an objective response. The median progression-free survival was 13.6 months (95% confidence interval, 9.5–16.5). Cell-free DNA–based tests may be a fast and convenient option to identify BRAF mutation status in melanoma patients, and help inform treatment decisions.

Real-world healthcare costs of localized and regionally advanced cutaneous melanoma in the Netherlands

The aim of this study was to provide insight into real-world healthcare costs of patients initially diagnosed with localized or regionally advanced melanoma in three Dutch hospitals between 2003 and 2011. Patients were stratified according to their stage at diagnosis and recurrence status. Costs were calculated by applying unit costs to individual patient resource use and reported for the full disease course, the initial treatment episode, and treatment episodes for disease recurrence (stratified by type of recurrence). We included 198 patients with localized melanoma and 98 patients with regionally advanced melanoma. Total costs were much higher for patients with disease recurrence than for patients without disease recurrence: €20 007 versus €3032 for patients with localized melanoma and €19 519 versus €5951 for patients with regionally advanced melanoma. This was owing to the costs of disease recurrence because the costs of the initial treatment were comparable between patients with and without disease recurrence. Costs of disease recurrence were dependent on the type of recurrence: €4414, €4604, €8129 and €10 393 for a local recurrence, intralymphatic metastases, regional lymph node metastases and distant metastases, respectively. In conclusion, healthcare costs of patients with localized and regionally advanced melanoma were rather low for the initial treatment. Costs became, however, more substantial in case of disease recurrence. In the context of a rapidly changing treatment paradigm, it remains crucial to monitor treatment outcomes as well as healthcare expenditures.

Targeting regulatory T cells for immunotherapy in melanoma

Regulatory T cells (Tregs) are essential in the maintenance of immunity, and they are also a key to immune suppressive microenvironment in solid tumors. Many studies have revealed the biology of Tregs in various human pathologies. Here we review recent understandings of the immunophenotypes and suppressive functions of Tregs in melanoma, including Treg recruitment and expansion in a tumor. Tregs are frequently accumulated in melanoma and the ratio of CD8+ T cells versus Tregs in the melanoma is predictive for patient survival. Hence, depletion of Tregs is a promising strategy for the enhancement of anti-melanoma immunity. Many recent studies are aimed to target Tregs in melanoma. Distinguishing Tregs from other immune cells and understanding the function of different subsets of Tregs may contribute to better therapeutic efficacy. Depletion of functional Tregs from the tumor microenvironment has been tested to induce clinically relevant immune responses against melanomas. However, the lack of Treg specific therapeutic antibodies or Treg specific depleting strategies is a big hurdle that is yet to be overcome. Additional studies to fine-tune currently available therapies and more agents that specifically and selectively target tumor infiltrating Tregs in melanoma are urgently needed.

Neoadjuvant Cytoreductive Treatment With BRAF/MEK Inhibition of Prior Unresectable Regionally Advanced Melanoma to Allow Complete Surgical Resection, REDUCTOR: A Prospective, Single-arm, Open-label Phase II Trial

OBJECTIVE

To evaluate the potency of short-term neoadjuvant cytoreductive therapy with dabrafenib plus trametinib (BRAF and MEK inhibitor) to allow for radical surgical resection in patients with unresectable locally advanced melanoma.

SUMMARY BACKGROUND DATA

Approximately 5% of stage III melanoma patients presents with unresectable locally advanced disease, making standard of care with resection followed by adjuvant systemic therapy impossible. Although neoadjuvant targeted therapy has shown promising results in resectable stage III melanoma, its potency to enable surgical resection in patients with primarily unresectable locally advanced stage III melanoma is still unclear.

METHODS

In this prospective, single-arm, phase II trial, patients with unresectable BRAF-mutated locally advanced stage IIIC or oligometastatic stage IV melanoma were included. After 8 weeks of treatment with dabrafenib and trametinib, evaluation by positron emission tomography/computed tomography and physical examination were used to assess sufficient downsizing of the tumor to enable resection. The primary objective was the percentage of patients who achieved a radical (R0) resection.

RESULTS

Between August 2014 and March 2019, 21 patients (20/21 stage IIIC American Joint Committee on Cancer staging manual 7th edition) were included. Planned inclusion of 25 patients was not reached due to slow accrual and changing treatment landscape. Despite this, the predefined endpoint was successfully met. In 18/21 (86%) patients a resection was performed, of which 17 were R0 resections. At a median follow-up of 50 months (interquartile range 37.7-57.1 months), median recurrence-free survival was 9.9 months (95% confidence interval 7.52-not reached) in patients undergoing surgery.

CONCLUSIONS

This prospective, single-arm, open-label phase II trial, shows neoadjuvant dabrafenib plus trametinib as a potent cytoreductive treatment, allowing radical resection of metastases in 17/21 (81%) patients with prior unresectable locally advanced melanoma.

The State of Melanoma: Emergent Challenges and Opportunities

Five years ago, the Melanoma Research Foundation (MRF) conducted an assessment of the challenges and opportunities facing the melanoma research community and patients with melanoma. Since then, remarkable progress has been made on both the basic and clinical research fronts. However, the incidence, recurrence, and death rates for melanoma remain unacceptably high and significant challenges remain. Hence, the MRF Scientific Advisory Council and Breakthrough Consortium, a group that includes clinicians and scientists, reconvened to facilitate intensive discussions on thematic areas essential to melanoma researchers and patients alike, prevention, detection, diagnosis, metastatic dormancy and progression, response and resistance to targeted and immune-based therapy, and the clinical consequences of COVID-19 for patients with melanoma and providers. These extensive discussions helped to crystalize our understanding of the challenges and opportunities facing the broader melanoma community today. In this report, we discuss the progress made since the last MRF assessment, comment on what remains to be overcome, and offer recommendations for the best path forward.

Completely resected stage III melanoma controversy - 15 years of national tertiary centre experience

BACKGROUND

Two prospective randomized studies analysing cutaneous melanoma (CM) patients with sentinel lymph node (SLN) metastases and rapid development of systemic adjuvant therapy have changed our approach to stage III CM treatment. The aim of this study was to compare results of retrospective survival analysis of stage III CM patients' treatment from Slovenian national CM register to leading international clinical guidelines.

PATIENTS AND METHODS

Since 2000, all Slovenian CM patients with primary tumour ≥ TIb are treated at the Institute of Oncology Ljubljana and data are prospectively collected into a national CM registry. A retrospective analysis of 2426 sentinel lymph node (SLN) biopsies and 789 lymphadenectomies performed until 2015 was conducted using Kaplan-Meier survival curves and log-rank tests.

RESULTS

Positive SLN was found in 519/2426 (21.4%) of patients and completion dissection (CLND) was performed in 455 patients. The 5-year overall survival (OS) of CLND group was 58% vs. 47% of metachronous metastases group (MLNM) (p = 0.003). The 5-year OS of patients with lymph node (LN) metastases and unknown primary site (UPM) was 45% vs. 21% of patients with synchronous LN metastasis. Patients with SLN tumour burden < 0.3 mm had 5-year OS similar to SLN negative patients (86% vs. 85%; p = 0.926). The 5-year OS of patients with burden > 1.0 mm was similar to the MLNM group (49% vs. 47%; p = 0.280).

CONCLUSIONS

Stage III melanoma patients is a heterogeneous group with significant OS differences. CLND after positive SLNB might still remain a method of treatment for selected patients with stage III.

Correlation of tumor-infiltrating immune cells of melanoma with overall survival by immunogenomic analysis

AIMS

Different types of tumor-infiltrating immune cells not only augment but also dampen antitumor immunity in the microenvironment of melanoma. Therefore, it is critical to provide an overview of tumor-infiltrating immune cells in melanoma and explore a novel strategy for immunotherapies.

METHODS

We analyzed the immune states of different stages in melanoma patients by the immune, stromal, and estimation of stromal and immune cells in malignant tumor tissues using expression data (ESTIMATE) scores. Immune cell types were identified by the estimating relative subsets of RNA transcripts (CIBERSORTx) algorithm in 471 melanoma and 324 healthy tissues. Moreover, we performed a gene set variation analysis (GSVA) to determine the differentially regulated pathways in the tumor microenvironment.

RESULTS

In melanoma cohorts, we found that ESTIMATE and immune scores were involved in survival or tumor clinical stage. Among the 22 immune cells, CD8⁺ T cells, M2 macrophages, and regulatory T cells (Tregs) showed significant differences using the CIBERSORTx algorithm. Furthermore, GSVA identified the immune cell-related pathways; the primary immunodeficiency pathway, intestinal immune network for IgA, and TGF-β pathways were identified as participants of the crosstalk in CD8⁺ T cells, Tregs, and M2 macrophages in the melanoma microenvironment.

CONCLUSION

These results reveal the cellular and molecular characteristics of immune cells in melanoma, providing a method for selecting targets of immunotherapies and promoting the efficacy of therapies for the treatment of melanoma.

The use of FDG-PET/CT to detect early recurrence after resection of high-risk stage III melanoma

BACKGROUND

The role of surveillance imaging in high-risk stage III melanoma patients after complete surgical resection remains controversial, and with the advent of adjuvant therapy, it may also be expanded. Therefore, we evaluated two fluorine-18 fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) protocols in two cohorts.

METHODS

Cohort 1 (n = 35) focused on surveillance in asymptomatic patients (before approval and reimbursement of adjuvant therapy) and was assigned to 5x FDG-PET/CT's after surgery: one every 6 months for 2 years, with one final scan after 3 years. Cohort 2 (n = 42) was assigned to one screening FDG-PET/CT, which took place in between surgery and the start of adjuvant treatment.

RESULTS

In cohort 1 (median follow-up: 33 months), 12 patients (34.3%) developed recurrence detected by FDG-PET/CT, of which 7 (20.0%) were detected with the first scan. Sensitivity and specificity were 92.3% and 100%, respectively. In cohort 2, recurrence was suspected on nine scans (21.4%) and four (9.5%) were true positive. The number of scans needed to find one asymptomatic recurrence were 8.8 and 10.5 in cohort 1 and 2, respectively.

CONCLUSIONS

FDG-PET/CT is a valuable imaging tool to detect recurrence in stage III melanoma, even shortly after surgery. A surveillance FDG-PET/CT protocol after surgery or a screening PET/CT before adjuvant therapy should be considered.

Anti-PD-1 and Novel Combinations in the Treatment of Melanoma-An Update

Until recently, distant metastatic melanoma was considered refractory to systemic therapy. A better understanding of the interactions between tumors and the immune system and the mechanisms of regulation of T-cells led to the development of immune checkpoint inhibitors. This review summarizes the current novel data on the treatment of metastatic melanoma with anti-programmed cell death protein 1 (PD-1) antibodies and anti-PD-1-based combination regimens, including clinical trials presented at major conference meetings. Immune checkpoint inhibitors, in particular anti-PD-1 antibodies such as pembrolizumab and nivolumab and the combination of nivolumab with the anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) antibody ipilimumab can achieve long-term survival for patients with metastatic melanoma. The anti-PD-1 antibodies nivolumab and pembrolizumab were also approved for adjuvant treatment of patients with resected metastatic melanoma. Anti-PD-1 antibodies appear to be well tolerated, and toxicity is manageable. Nivolumab combined with ipilimumab achieves a 5 year survival rate of more than 50% but at a cost of high toxicity. Ongoing clinical trials investigate novel immunotherapy combinations and strategies (e.g., Talimogene laherparepvec (T-VEC), Bempegaldesleukin (BEMPEG), incorporation or sequencing of targeted therapy, incorporation or sequencing of radiotherapy), and focus on poor prognosis groups (e.g., high tumor burden/LDH levels, anti-PD-1 refractory melanoma, and brain metastases).