Chinese Melanoma Research Articles

Comprehensive insights on genetic alterations and immunotherapy prognosis in Chinese melanoma patients

Immune checkpoint inhibitors (ICI) have emerged as a promising therapeutic option for melanoma, which demonstrating improved clinical outcomes in melanoma patients regardless of specific genetic mutations. However, the identification of reliable biomarkers for predicting immunotherapy response and prognosis remains a challenge. In this study, we performed genetic profiling of the melanoma patients with different subtypes and evaluated the efficacy of ICI treatment. A total of 221 melanoma patients were included in our cohort, consisting primarily of acral lentiginous melanoma (ALM), cutaneous malignant melanoma (CMM), and mucosal malignant melanoma (MMM). Genetic analysis revealed BRAF mutations was predominant in CMM and NRAS mutations was prevalent in ALM. Copy number variants (CNVs) and structural variants (SV) were also detected, with CCND1 and CDK4 being the most affected genes in CNV and BRAF, ALK and RAF1 being the druggable targets in SV. Furthermore, NRAS mutations were associated with a poor prognosis in ALM, while TERT mutations were linked to unfavorable outcomes in CMM after receiving PD-1 therapy. Additionally, ALK expression exhibited improved outcomes in both ALM and CMM subtypes. Our study provides a comprehensive genomic and pathological profiling of Chinese melanoma patients, shedding light on the molecular landscape of the disease. Furthermore, numbers of gene mutations and ALK expression were identified as prognostic indicators. These findings contribute to the understanding of melanoma genetics in the Chinese population and have implications for personalized treatment approaches.

The efficacy and safety of toripalimab combined with anlotinib in the first-line treatment of Chinese patients with metastatic melanoma.

9560 Background: Acral, mucosal and non-CSD melanoma are the major subtypes in Chinese melanoma patients, with poor response to antiprogrammed cell death-1 (PD-1) monotherapy. Anti PD-1 monoclonal antibodies combined with anti-angiogenesis agent have showed synergistic effects mechanically and a promising response rate. Here, we report efficacy and safety of toripalimab combined with anlotinib in Chinese patients with metastatic melanoma. Methods: Patients with metastatic acral, mucosal and non-CSD melanoma received toripalimab 240mg intravenously every 3 weeks combined with anlotinib 12 mg orally once a day for first 2 weeks every 3 weeks as first-line treatment, until disease progression or unacceptable toxicity. All patients were enrolled from the Cancer Center of Union Hospital, affiliated to Tongji Medical College of Huazhong University of Science and Technology and Hunan Cancer Hospital. Results: From January 2021 to January 2024, a total of 47 patients were enrolled in this study. Subtypes were 16 patients with acral melanoma, 21 patients with mucosal melanoma, and 10 patients with non-CSD melanoma. Average age was 59.7 ±10.1 years old. The median follow-up was 26.5 months (95% CI: 20.6, 32.4 months). Among the 46 efficacy evaluable patients, the objective response rate (ORR) and disease control rate (DCR) were 23.9% and 80.4%, respectively. Median duration of response was 14.4 months (95% CI: 7.5, 21.3). The median progression-free survival (PFS) of all 47 patients was 5.7 months (95% CI 4.2 to 7.2 months); and the median OS was 14.4 months (95% CI 7.3 to 21.5 months). The median PFS of patients with M1a stage is 24.4 months, statistically longer than M1b (5.1 months), M1c (6.6 months) and M1d (4.0 months). The median PFS of acral, mucosal and non-CSD melanoma were 6.6m, 5.1m, 5.2m respectively with no statistical difference, and these is no difference of PFS between gender and age. In terms of safety, treatment-related adverse events (TRAEs) for all grades occurred in 76.6% (36/47) of patients, and grade 3 or 4 occurred in 4.3% (2/47) of patients. The incidence of immune-related adverse reactions (irAE) was 23.4% (11/47) for all grades, the most common irAEs (≥2%) included hypothyroidism, immune-associated hepatitis and rash. Conclusions: Toripalimab combined with anlotinib displays good efficacy and well-tolerant safety profiles in the treatment of patients with metastatic melanoma. Further biomarker analysis was ongoing.

Slow Mohs micrographic surgery for nail apparatus melanoma in situ.

Nail apparatus melanoma is a malignant tumor with a high incidence in Chinese melanoma patients. Slow Mohs micrographic surgery is an emerging technique for treating nail apparatus melanoma in situ (NAMIS). This study evaluated the efficacy and safety of slow Mohs micrographic surgery for treating NAMIS. Patients were enrolled in this retrospective study and treated in a single center from October 1, 2016, to June 30, 2022. Each patient underwent standard slow Mohs micrographic surgery, and follow-up was regularly conducted at clinics. Ten patients were enrolled in the study. Two patients underwent one Mohs stage, seven underwent twoMohs stages, and one underwent seven Mohs stages. The resection margin ranged from 5 to 25 mm. No severe complications were reported in the treatment, and recurrence of NAMIS was not observed during the follow-up period. Slow Mohs micrographic surgery is a valuable surgical method to treat NAMIS that preserves digit function and can be well tolerated by patients.

Survival impact of immediate complete lymph node dissection for Chinese acral and cutaneous melanoma with micrometastasis in sentinel nodes: a retrospective study

Sentinel node biopsy (SNB) has become a critical part of standard surgical treatment for melanoma with no clinical metastatic evidence. However, for patients with a positive sentinel node, the MSLT-II and DeCOG-SLT trials have shown that immediate complete lymph node dissection (CLND) does not bring further survival benefits. There is still an argument among the Chinese population dominated by acral subtypes on whether CLND can be omitted. Thus, this study aims to investigate the impact of immediate CLND on relapse-free survival (RFS) in Chinese melanoma patients with a positive sentinel node. Patients with acral or cutaneous melanoma of clinical Stages I–II who received SNB procedure and were detected with nodal micrometastasis were retrospectively collected at Fudan University Cancer Center (FUSCC) from January 2017 to December 2021. The clinicopathologic features and prognostic factors for RFS were analyzed. Out of 381 patients who received SNB in the past 5 years, 130 (34%) cases with SN micrometastasis detected were included in this study. Ninety-nine patients underwent immediate CLND while the other 31 patients received observation alone. Among patients who received CLND, the non-SN(NSN)-positive rate was 22.2%. Most of the clinicopathologic factors were balanced well between the CLND and non-CLND groups. However, more patients in the CLND group were detected with BRAF and NRAS mutation (P = 0.006) and received adjuvant PD-1 monotherapy (P = 0.042) as well. There were slightly fewer N1 patients in the CLND group, although the difference did not reach statistical significance (P = 0.075). The study found no significant difference in RFS between the two groups (P = 0.184). Even for patients with the acral subtype (P = 0.925), primary T4 lesion (P = 0.769), or presence of ulceration (P = 0.249), immediate CLND did not bring more survival benefits. Immediate CLND did not bring further RFS benefit for Chinese melanoma patients with SN micrometastasis in real-world clinical practice, even for patients with acral subtype or more tumor burden such as thick Breslow invasion and ulceration.

Comparative analysis of adjuvant therapy for stage III BRAF-mut melanoma: A real-world retrospective study from single center in China.

BRAF V600 mutation is the most common oncogenic alternation in melanoma and is visible in around 50% of cutaneous and 10%-15% of acral or mucosal subtypes. Currently, immunotherapy with anti-PD-1 blockade and dual-targeted therapy with Dabrafenib plus trametinib (D + T) target therapy have been approved as adjuvant therapies for Stage III melanoma with BRAF V600 mutation. According to their phase III clinical trials, 3-year recurrence-free survival (RFS) is around 60% for both types of treatment. However, early disease control was slightly more effective with targeted therapy than immunotherapy. With different drug approval deadlines in China, anti-PD1 monotherapy, D + T combination, and Vemurafenib (V) monotherapy have all been used in real clinical practice as adjuvant settings for stage III BRAF-mut melanoma in recent years. We conducted this retrospective study to evaluate the efficacy of different treatments in the Chinese melanoma population. Patients who underwent radical surgery and were diagnosed as Stage III melanoma harboring BRAF V600 mutation by pathological report were retrospectively identified at Fudan University Shanghai Cancer Center from January 2017 to December 2021. Patients with mucosal melanoma, or with follow-up of <6 months, or receiving other adjuvant treatment were excluded. Pearson's chi-squared test or Fisher's exact test was performed for univariable analysis of the different adjuvant groups. Log-rank analysis was used to identify prognostic factors for relapse-free survival (RFS). Ninety-three patients with resected stage III melanoma with BRAF V600E mutation were identified in our study, including 25 patients receiving adjuvant anti-PD-1 immunotherapy (PD-1), 25 receiving adjuvant D + T, 23 receiving V, and 20 patients with observation-only (OBS). There were no statistical differences between treatment groups in baseline characteristics including age, gender, subtypes, primary thickness, ulceration, and nodal involvement. Median relapse-free survival (RFS) time was not reached in the D + T group, 15 months in the V group, 15 months in the PD-1 group, and 10 months in the OBS group, respectively. Compared to OBS, all three other groups showed a tendency to benefit from RFS, while only D + T achieved a statistical difference (p = 0.002). However, compared to D + T, anti-PD-1 monotherapy also showed significantly worse relapse control (p = 0.032). For Chinese stage III melanoma with BRAF mutation, both novel targeted therapy and immunotherapy showed potential benefits in relapse-free survival compared to observation only. Dual-targeted D + T therapy may still be the best choice for adjuvant therapy because anti-PD-1 monotherapy has failed to report equivalent efficacy in real-world practice.

Prognostic value of genetic aberrations and tumor immune microenvironment in primary acral melanoma

BackgroundAcral melanoma (AM) is the most common subtype in Chinese melanoma patients with a very poor prognosis. However, our understanding of the disease pathogenesis and molecular landscape is limited by the few studies that have been conducted. Here, we profiled the clinical characteristics, mutational landscapes and tumor immune microenvironment of AM patients to gain insights into disease characteristics and potential treatment strategies.MethodsA total of 90 AM patients were enrolled and their tissue samples were subjected to next-generation sequencing and multiplexed immunohistochemistry tests. Kaplan–Meier curves and log-rank tests were used to analyze the prognostic potential of various genetic aberrations and immune cell compositions in AM.ResultsThe median disease-free survival was 21.3 months and estimated median overall survival (OS) was 60 months. More advanced stages, older ages and thickness of greater than 4 mm were associated with worse prognosis in AM patients (HR = 2.57, 95% CI 1.25–5.29, p = 0.01; HR = 2.77, 95% CI 1.22–6.28, p = 0.02; HR = 3.43, 95% CI 1.51–7.82, p < 0.01, respectively), while patients who received post-surgical treatments had better survival (HR = 0.36, 95% CI 0.17–0.76, p = 0.01). The most frequently altered genes included BRAF (14.5%), KIT (16.9%), NRAS (12%), NF1 (10.8%), APC (7.2%), and ARID2 (6%). Copy number variations (CNV) were commonly found in CCND1 (19.3%), CDK4 (19.3%), MDM2 (14.5%) and FGF19 (12%). CDK4 amplifications was independently associated with shorter OS in AM patients (HR = 3.61, 95% CI 1.38–9.46, p = 0.01). CD8 + T cells (p < 0.001) and M1 macrophages (p = 0.05) were more highly enriched in the invasive margin than in the tumor center. Patients with higher levels of M1 macrophage infiltration in the invasive margin derived markedly longer OS (HR = 0.43, 95% CI 0.20–0.95, p = 0.03). Interestingly, in CDK4-amplified patients, there tended to be a low level of M1 macrophage infiltration in the invasive margin (p = 0.06), which likely explains the poor prognosis in such patients.ConclusionsOur study provided a comprehensive portrait of the clinicopathological features, genetic aberrations and tumor microenvironment profiles in AM patients and identified candidate prognostic factors, which may facilitate development of additional therapeutic options and better inform clinical management of AM patients. Based on these prognostic factors, further studies should focus on enhancing the infiltration of M1 macrophages, especially in CDK4-amplified AM patients.

Genomic and Transcriptional Profiling of Chinese Melanoma Patients Enhanced Potentially Druggable Targets: A Multicenter Study

In contrast to Caucasian melanoma, which has been extensively studied, there are few studies on melanoma in Asian populations. Sporadic studies reported that only 40% of Asian melanoma patients could be druggable, which was much lower than that in Caucasians. More studies are required to refine this conclusion. Chinese melanoma patients (n = 469) were sequentially sequenced by DNA-NGS and RNA-NGS. The genomic alterations were determined, and potentially actionable targets were investigated. Patients with potential druggable targets were identified in 75% of Chinese melanoma patients by DNA-NGS based on OncoKB, which was much higher than in a previous Asian study. NRG1 fusions were first identified in melanoma. In addition, up to 11.7% (7/60) of patients in the undruggable group could be recognized as actionable by including RNA-NGS analysis. By comparing the fusion detection rate between DNA-NGS and RNA-NGS, all available samples after DNA-NGS detection were further verified by RNA-NGS. The use of RNA-NGS enhanced the proportion of druggable fusions from 2.56% to 17.27%. In total, the use of RNA-NGS increased the druggable proportion from 75% to 78%. In this study, we systemically analyzed the actionable landscape of melanoma in the largest Asian cohort. In addition, we first demonstrated how DNA and RNA sequential sequencing is essential in bringing clinical benefits to more patients with melanoma.

Clinical features and response to systemic therapy in NRAS-mutant Chinese melanoma patients.

The prognosis of patients with NRAS-mutant melanoma is rather poor. Immunotherapy and targeted therapy have revolutionized anti-tumor therapy, especially for melanoma. In this study, we retrospectively summarized the real-world experience of systematic treatment for NRAS-mutant melanoma patients in this new era. The respective cohort included NRAS-mutant melanoma patients with metastatic or unresectable disease of Sun Yat-sen University Cancer Center (SYSUCC) from January 2018 to July 2022. The data about the clinical features and impact for systemic therapy of NRAS-mutant patients were collected and analyzed. At data cutoff, 44 patients (19, 11, and 14 for acral, cutaneous, and mucosal ones, respectively) with NRAS-mutant were assessed. In addition, the median time of follow-up was 22.0months. The immunotherapy-based combined treatment not only significantly improved the progression-free survival (PFS) (P = 0.006, HR 0.322), but was also accompanied by a higher objective response rate (ORR) (18.2%), disease control rate (DCR) (72.7%) than those of cytotoxic therapy or immunotherapy alone for advanced patients as first-line treatment. Nab-paclitaxel combined with anti-PD-1 inhibitor tended to produce better clinical benefit for the first-line treatment, especially for patients with acral melanoma. In addition, the tyrosine kinase inhibitor (TKI) combined with anti-PD-1 inhibitor also seemed to provide longer duration of response (DOR) for some patients. But combined therapy did not prolong the overall survival (OS) of NRAS-mutant patients. The combined therapy was well tolerated. Most adverse events were moderate and controllable. In conclusion, PD-1 inhibitor-based combined therapy increased clinical benefit for advanced patients with NRAS-mutant melanoma.

Delay in Seeking Medical Attention and Diagnosis in Chinese Melanoma Patients: A Cross-Sectional Study.

Melanoma is a highly malignant skin tumor, and prolonged delay in seeking medical attention (DSMA) and delay in diagnosis (DD) may result in poor prognoses. Through a web-based questionnaire, we explored the related factors affecting the DSMA and DD of melanoma in a Chinese population. A total of 112 valid answer sheets were received. After obtaining the relevant information, we analyzed the factors associated with DSMA and DD. The median time of DSMA was 8.0 (quartiles: 1.0, 29.3) months, and the median of patients' DD was 1.0 (quartiles: 1.0, 8.3) month. The subsequent analysis showed that DSMA and DD were positively correlated to age and negatively correlated to education background and annual household income. Patients with a history of tumors or previous health-seeking behavior because of other skin lesions had significantly longer DSMA than those without. Patients who sought medical help at general tertiary hospitals for the first time had a significantly shorter DD than those who chose other hospitals. Our study found that DSMA and DD are associated with factors such as age, education, income, and patients' histories. Secondary prevention of Chinese melanoma should be strengthened to reduce DSMA and DD to improve patients' prognoses.

Intratumoral CD73: An immune checkpoint shaping an inhibitory tumor microenvironment and implicating poor prognosis in Chinese melanoma cohorts.

BackgroundAs a novel immune checkpoint, CD73 has been reported to play prominent roles in several malignancies. However, the significance of CD73 in melanoma remains ambiguous. This study sought to reveal the impact of CD73 on the tumor microenvironment (TME) and patients’ prognosis, and to investigate whether CD73 could be a therapeutic target in Chinese melanomas, which were dominated by acral and mucosal subtypes.MethodsTwo independent Chinese cohorts of 194 patients with melanoma were enrolled. CD73 and PD-L1 expression as well as CD8+ and CD56+ cell infiltrations were evaluated by immunohistochemistry in 194 resected melanoma samples. Clinical outcomes of patients were assessed utilizing the Kaplan-Meier plotter and Cox proportional hazard analysis. RNA-seq data was obtained from TCGA database. Gene set functional annotations were performed based on GO, KEGG and GSEA analysis. CIBERSORT, ssGSEA and TIMER were used to explore the association between CD73 and immune infiltration. These findings were validated by establishing tumor xenograft model, and functions of tumor-infiltrating immune cells were examined by flow cytometry and immunofluorescence.ResultsHigh CD73 expression showed poorer clinical outcomes and was identified as an independent prognostic indicator for survival in two cohorts. Expression of CD73 was more prevalent than PD-L1 in Chinese melanoma cohorts (54.6% vs 23.2%). Co-expression of both immune checkpoints was infrequent (12.9%) in melanoma, and 54.4% of PD-L1 negative cases showed elevated expression of CD73. CD73high tumors showed a microenvironment with fewer CD8+ T cells and CD56+ NK cells infiltration, which displayed a dysfunctional phenotype. With the treatment of CD73 inhibitor APCP, the amount of CD8+ T cells and CD56+ NK cells infiltrated in tumors was elevated and the immunosuppressive effect of CD73 was eliminated.ConclusionsHigh CD73 expression was associated with an inhibitory TME and adverse clinical outcomes of melanoma. In comparison to PD-L1, CD73 was more prevalent and possessed more definite prognostic significance. Therefore, it may serve as a prognostic indicator and immunotherapeutic target next to PD-L1 in melanoma for Chinese population.

HHLA2 predicts improved prognosis of anti-PD-1/PD-L1 immunotherapy in patients with melanoma.

BackgroundAs a recognized highly immunogenic tumor, immune checkpoint blockades (ICB) have been widely used as a systemic treatment option for melanoma. However, only about half of treated patients could benefit from it in Caucasians, and only about 15% in Chinese melanoma patients. Robust predictive biomarkers are needed. HHLA2, a new-found member of B7 family, is generally expressed in kinds of tumors, such as melanoma. This study focuses on illustrating the prognostic value of HHLA2 in melanoma immunotherapy and its association with tumor-infiltrating lymphocytes.MethodsHHLA2 expression in pan-cancer and the association with prognosis and immune microenvironment were identified by analyzing gene expression profiles from TCGA database with selected bioinformatics tools and methods. Tumor tissues from 81 cases with advanced and unresectable melanoma were collected for detecting HHLA2 and CD8 levels by immunohistochemistry.ResultsHHLA2 was found to be ubiquitously expressed in pan-cancer with high level and correlate with the prognosis of patients. Further comprehensive analysis from TCGA database demonstrated that the highly expressed HHLA2 was remarkably correlated with better prognosis, high infiltration status of various immune-active cells and immune activated pathways in skin cutaneous melanoma (SKCM). Moreover, immunohistochemistry (IHC) analyses of FFPE tissue from melanoma patients revealed that HHLA2 high expression was strongly related to improved response to ICB and indicated a longer progression-free survival (PFS) and overall survival (OS). Besides, HHLA2 expression was found to have a positive association with the density of CD8+ TILs.ConclusionOur findings revealed that high expression of HHLA2 has important values in predicting the response to ICB and indicating improved PFS and OS in patients with advanced and unresectable melanoma, suggesting that HHLA2 may serve as a costimulatory ligand in melanoma, which renders it as an ideal biomarker for immunotherapy.

Next-generation sequencing in advanced Chinese melanoma reveals therapeutic targets and prognostic biomarkers for immunotherapy

Limited studies have interrogated the genomic landscape of Chinese melanoma in which acral and mucosal melanoma are the mainstay. In this study, we carried out a retrospective analysis on 81 Chinese melanoma patients (15 acral, 25 mucosal and 41 cutaneous melanoma). With the identification of 1114 mutations spanning 248 genes, we summarized that the mutation spectrum varied significantly by subtypes. Acral melanoma and mucosal melanoma had significantly more CNVs. MYC amplification was one of the most commonly detected CNVs, other frequent CNVs in mucosal melanoma included NBN and KDR, which were associated with the poor survival of melanoma patients. A generally low TMB, with a median of only 5.1 mut/Mb, was observed in three groups including cutaneous melanoma. Additionally, over 50% variants in DNA damage repair pathway were detected in all three subtypes, most of which were HRD related genes. Patients with alterations of HRD related genes had a longer survival time after immunotherapy. This study revealed a molecular profiling of Chinese patients with advanced melanoma, and proposed the high variant rate in DDR pathway as a biomarker of immunotherapy, which might provide therapeutic targets and guidance in making clinical decision for different Chinese melanoma.

Toripalimab: the First Domestic Anti-Tumor PD-1 Antibody in China.

Toripalimab (Tuoyi™) is a selective, recombinant, humanized monoclonal antibody against programmed death protein 1 (PD-1) developed by Shanghai Junshi Bioscience Co., Ltd. Toripalimab is able to bind to PD-1 and block the interaction with its ligands. The binding of toripalimab to PD-1 is mainly attributed to the heavy chain of the former and the FG loop of the latter. Toripalimab received a conditional approval in China for the treatment of melanoma (second-line) in December, 2018. It has also received approvals to treat nasopharyngeal carcinoma (first-line and third-line) and urothelial carcinoma (second-line) in 2021. Additionally, several orphan drug designations were granted to toripalimab by the US Food and Drug Administration. Toripalimab has exhibited primary anti-tumor effects in tumors such as melanoma, lung cancer, digestive tract tumors, hepatobiliary and pancreatic tumors, neuroendocrine neoplasms, nasopharyngeal carcinoma and urothelial carcinoma. It showed a satisfactory anti-tumor effect and long-term survival benefits in Chinese melanoma patients, while the combination of axitinib with toripalimab exhibited an impressive result in metastatic mucosal melanoma. As a checkpoint inhibitor, toripalimab was generally well-tolerated in the enrolled patients. Due to different study populations, comparisons could not be made directly between toripalimab and other drugs in most cases. Nevertheless, the introduction of toripalimab may offer a valuable choice for decision-making in the treatment of tumors in the future.

BRAF, C-KIT, and NRAS mutations correlated with different clinicopathological features: an analysis of 691 melanoma patients from a single center.

BackgroundDiscrepancies in genetic alterations found in melanoma are conspicuous between different ethnic groups. With the approval of BRAF- and MEK-targeted inhibitors in China, it is necessary to further elucidate the landscape of gene mutation in Chinese melanoma patients.MethodsThe frequency and distribution of BRAF, C-KIT, and NRAS mutations in 691 melanoma patients was determined, and the statistical significance of correlations between different gene mutations and clinicopathological features was analyzed.ResultsAmong a total of 691 patients, BRAF mutation was found in 166 patients (24.0%), and V600E was the prominent genetic alteration (145/166, 87.3%). Statistical analyses showed that younger patients (<60) had a higher BRAF mutation rate than older patients (≥60, P=0.000), and the frequency of BRAF mutation was more likely to be lower in patients with the following: melanoma located in an extremity (P=0.000), acral-lentiginous melanoma subtype (P=0.000), thinner melanoma thickness (P=0.047), and no ulceration (P=0.030). The frequency of NRAS mutation was 12.6% (38/302), and primarily involved codon 61 in exon 3 and codon 12 in exon 2. Mutation of C-KIT was detected in 65 patients (9.4%), and the most common site of mutations was L576 in exon 11 (29/65, 44.6%). Patients with NRAS or C-KIT mutation had higher Clark level (P=0.035 and 0.047, respectively) and were more likely to have melanoma located in an extremity (P=0.003 and 0.009, respectively) than those without such mutation. The concordance of gene mutations between paired primary and metastatic lesions was 89.6% (60/67), and visceral metastases showed the highest distribution of gene mutations versus primary melanomas (100.0%) compared with lymph nodes (90.9%) and cutaneous metastases (83.3%).ConclusionsIn this large cohort of Chinese melanoma patients, the frequencies of BRAF and NRAS mutations were lower than those observed in Caucasian cohorts, but the clinicopathological features of BRAF, C-KIT, and NRAS mutation were consistent. Paired primary and metastatic lesions showed high concordance of gene mutations.

The efficacy and safety analysis of PD-1 inhibitor combined with interferon-α1b: A real-world study in Chinese metastatic melanoma patients.

e21507 Background: Clinical data on PD-1 inhibitor combined with interferon in metastatic melanoma treatment were still limited. The objective of this study was to assess the efficacy and safety of PD-1 inhibitor/interferon-α1b combination therapy for Chinese metastatic melanoma patients in the real world. Methods: We reviewed patients diagnosed as metastatic melanoma and had received PD-1 inhibitor (pembrolizumab, 2 mg/kg, every 3 weeks, intravenously or toripalimab 240mg every 2 weeks, intravenously) combined with interferon-α1b(10μg/kg, every other day, subcutaneously) in Xijing Hospital from Dec 2018 to Nov 2020. Efficacy and safety profiles were evaluated using Response Evaluation Criteria in Solid Tumors version 1.1 and Common Terminology Criteria for Adverse Events version 5.0, respectively. Results: In total 65 patients were reviewed in this study, including 13 cases with ECOG performance status ≥2. Acral and mucosal cases accounted for 47.7% and 23.1% respectively. In 27(41.5%) patients, the combination therapy was used as the first line treatment, whereas in the rest 38 patients as second or subsequent lines. The median follow-up period was 8 months (1.5-21 months). Median OS was 15 months (95CI%: 10.62-19.38 months). Median PFS was 6 months (95CI%: 2.54-9.46 months). 6-month and 1-year PFS rate were 48.1% and 35.3%. 6-month and 1-year OS rate were 80.9% and 59.8%. Objective response was seen in 18.46% cases, with 12.31% of patients exhibiting ongoing response. The best confirmed disease control rate was 73.85%. Multivariate analysis demonstrated that overall survival was significantly associated with ECOG performance status ≥2 (OR=3.32，95%CI=1.14-9.66 ), regardless of age(≥65), elevated LDH, PD-1 inhibitor type and the line of the combination therapy. Select treatment related AEs (TRAEs) of any grade were observed in 57(87.69%) patients. The leading 3 TRAEs were lymphopenia, fatigue and fever. Grade 3 to 4 TRAEs were recorded in 2 cases. Grade 4 hyponeutrophilia occurred in a patient with ECOG status 3 using interferon-α1b plus toripalimab and resulted in discontinuation of both PD-1 inhibitor and IFN-α1b. Grade 3 headache was reported by one patient using interferon-α1b plus pembrolizumab and was solved with celecoxib 200mg daily. No drug-related deaths were reported. Conclusions: PD-1 inhibitor combining interferon-α1b therapy shows promising efficacy and acceptable toxicity in this real-world cohort of Chinese metastatic melanoma patients.[Table: see text]

Four-year survival follow-up of toripalimab (JS001) as salvage therapy in Chinese melanoma patients.

e21522 Background: Toripalimab, a PD-1 monoclonal antibody received conditionally approval in China as a salvage therapy for metastatic melanoma in 2018 based on a phase II trial with confirmed objective response rate of 17.3%. With four-year survival follow-up, here we report long-term survival results and related predictive biomarkers (NCT03013101). Methods: Patients with advanced melanoma who had failed prior systemic treatments were given toripalimab at 3 mg/kg i.v. Q2W until disease progression, intolerable toxicity or 2-year of treatment. Pts were followed for survival every 3 mo after discontinuation of treatment. Pts were transferred to an extension study after 2-year treatment. The Primary endpoint for the extension study was overall survival (OS). Results: 127 pts were enrolled, including50 (39.4%) acral, 22 (17.3%) mucosal, 29 (22.9%) nonacral cutaneous, and 26 (20.5%) unknown primary subtypes. After a median follow-up of 16.5 mo (range, 0.9-48.8), 74 (58%) pts had died. Median duration of response was 25.6 mo (95%CI:12.8-NE). Median OS was 22.0 mo (95%CI: 15.3-32.5). The OS rates for year 1 to 4 were 67.1%, 48.2%, 38.0% and 31.7% respectively. The median OS of complete response (CR)/ partial response (PR) (n = 22), stable disease (SD) (n = 51), progression disease (PD) (n = 54) were not reached, 34.0 mo and 9.7 mo, respectively. The median OS of non-acral cutaneous, unknown primary, acral and mucosal melanoma subtypes were 46.1, 37.3, 16.9 and 10.3 mo, respectively. The median OS of PD-L1+ (n = 26) and PD-L1- (n = 84) patients were 46.1 and 14.4 mo (P = 0.026, HR = 0.45, 95%CI 0.26-0.76). The median OS of TMB high (n = 20), TMB low (n = 78) was 16.0 and 22.3 mo with no statistically significance (P = 0.49, HR = 1.28, 95%CI 0.63-2.58). Conclusions: Salvage treatment with toripalimab leads to long-term survival benefit in advanced melanoma patients, especially for those with non-acral cutaneous and unknown primary subtypes, CR/PR/SD as best response or PD-L1+.

Genetic landscape of melanoma in China reveals enrichment of fusions in driver-negative melanoma.

e21577 Background: Melanoma in China has unique characteristics, especially compared with those in euramerican white race. In european and american countries, nearly 90% of melanoma patients are cutaneous melanoma; while 60% of melanoma in China are acral melanoma, accompanied with a considerable proportion of mucosal melanoma. Mapping the mutation landscape of melanoma in China can provide an important basis for targeted therapy of melanoma patients. Methods: Tissue samples from 223 patients with melanoma were sequenced using multi-gene NGS panel Onco PanScan to detect somatic mutations in melanoma. Results: As a result, BRAF (24.2%) and NRAS (15.7%) were the top two most mutated driver genes. In BRAF, V600E was the most common mutation, which accounted for 80% of all BRAF mutations. And Q61R/K was the most common mutation in NRAS, which accounted for 68.6% of all NRAS mutations. As to CNVs, the most frequently amplified genes were CCND1 (23, 10.3%), CDK4 (18, 8.1%), MDM2 (17, 7.6%), FGF19 (16, 7.2%), FGF4 (13, 5.8%), FGF3 (12, 5.4%), KIT (12, 5.4%), RICTOR (12, 5.4%). At the same time, a small number of EGFR, HER2, MET, MYC amplifications were detected. Interestingly, a considerable proportion of CNVs were related with hyperprogressive disease, including amplification of MDM2, CCND1, FGF3, FGF4, FGF19. Except for SNVs and CNVs, 16 gene fusions were detected in 13 samples (5.8%), among which the frequency of fusions involving BRAF, ALK, RAF1 was 2.2% (5/223), 1.3% (3/223) and 1% (2/223) respectively. Among these 16 fusions, only 4 fusions (AGAP3-BRAF, GTF2I-BRAF, TPM3-ALK, DCTN1-ALK) were reported previously, leaving the remaining 12 fusions new detected. As was reported, AGAP3-BRAF fusion was the mechanism by which melanoma patients with BRAF V600E mutations developed resistance to vemurafenib; GTF2I-BRAF fusion mediated the activation of MAPK pathway in fibrous astrocytoma. At last, we also compared the frequency of fusion detected in driver-positive and driver-negative melanoma (no somatic mutations detected in BRAF, HRAS, KRAS, NRAS, NF1, KIT, GNAQ, GNA11), and the result showed the frequency of fusion detected in driver-negative melanoma was significantly higher (9/78, 11.5% vs. 4/145, 2.8%). Conclusions: Through DNA-based NGS, the mutation landscape of Chinese melanoma patients was depicted. BRAF was the most frequently mutated driver gene with the main mutation type of V600E (19.7%) which was significantly lower than that of white race in TCGA-SKCM database (44.2%). On the other hand, DNA-based NGS can detect potentially druggable fusions, and compared with driver positive melanoma patients, fusions were enriched in patients with no driver mutations detected. Perhaps for driver negative melanoma patients, RNA-based NGS should be used to detect more potential druggable fusions which would bring clinical benefit.

Frequency of homologous recombination deficiency gene mutations in melanoma and its relevance to the immunotherapeutic response.

e15073 Background: Homologous recombination deficiency (HRD) can regulate the tumor immune microenvironment based on increasing tumor-infiltrating lymphocytes and therefore might serve as a biomarker of immunotherapeutic response. The HRD phenotype has been defined as the presence of a non-silent somatic mutation in homologous recombination-related (HRR) genes. Here, we focused on frequency of HRR genes mutation and the relationship between HRR genes mutation and clinical immunotherapy responses in melanoma. Methods: We prospectively sequenced 130 Chinese melanoma patients using next-generation sequencing techniques with Acornmed panel with 808 cancer-related genes. 208 patients with WES data from the TCGA project were included. Correlations between HRR gene mutations and clinical outcomes were identified via bioinformatic analysis using TCGA datasets. Results: In the Chinese cohort, 40% (52/130) patients exhibited genomic alterations in HRR genes. The frequently mutated genes were ATM (14%), BRCA2 (13%), CHEK2 (6%), PALB2 (6%), BRIP1 (4.6%), BARD1 (3%), BRCA1 (2%), CDK12 (2%), CHEK1 (1%), FANCL (1%), and RAD54L (1%). In TCGA cohort, 26% (53/208) patients had at least one somatic mutation in an HRR gene. The frequently mutated genes were BRCA2 (9%), BRCA1 (7%), ATM (6%), BRIP1 (4%), PALB2 (4%), BRAD1 (1%), CHEK2 (1%), PPP2R2A (1%), RAD51B (1%), RAD51C (1%), RAD54L (1%), CHEK1 (1%), and RAD51D. Chinese melanoma patients had higher frequently mutated HRR genes compared to that in TCGA patients (40% vs 26%, p=0.005). In addition, compared with TCGA cohort, the Chinese cohort had higher frequency for ATM (14% vs 6%, p=0.019) and CHEK2 (6% vs 2%, p=0.006). The TCGA cohort had a higher frequency of BRCA1 mutations than the Chinese cohort, although the difference was not statistically significant. Unfortunately, we did not find a significant correlation between HRR mutation and immune cells. Interestingly, in the TCGA cohort, patients with HRR-mut had significantly better OS than patients with HRR-wt (log-rank p=0.027). Conclusions: Our data suggest that detection of somatic mutations in HRR genes might contribute to identify patients who might benefit from immune checkpoint blockade therapy. In addition, the molecular features of HRD provide new opportunities to predict the tumor response to multiple treatments.[Table: see text]

Correlation analysis of gene and immune microenvironment for 87 melanoma cases.

e21555 Background: To map the genome of Chinese melanoma patients and explore its correlation with the expression of tumor immune microenvironmental indicators. Methods: Next generation sequencing was performed on 87 cases of primary melanoma that had been surgically removed from Nanjing Drum Tower Hospital from July 2010 to May 2017. Immunohistochemistry was carried out to detect the expressions of PD1, PDL1, CD3+TIL, MSH2, MSH6, PMS2 and MLH1. Results: BRAF mutations were the most common (26.4%), followed by KIT mutations (12.6%) in melanoma patients. RB1 gene copy number deletion (55%) and CDK4 (25%)/CCND1 (22.5%) gene copy number amplification were also common. The prognosis of patients could be distinguished by grouping the expression of PDL1 and TIL, and the difference may be related to the expression of PD1. There were more copy number amplication of genes with poor prognosis in PDL1-TIL- patients. Conclusions: The classification of tumors into four microenvironmental subtypes based on PDL1 and TIL expression is an appropriate method to stratify patients with different clinical outcomes. At the genetic level, there are more copy number amplification of the genes with poor prognosis in patients with TIL-PDL1- type, so the prognosis is always worse than that of patients with TIL+PDL1+ type. Gene may affect the prognosis of patients by affecting the tumor immune microenvironment.

Survival Benefits of Anti-PD-1 Therapy in Combination With Radiotherapy in Chinese Melanoma Patients With Brain Metastasis.

Limited data reported the synergistic anti-tumor effect of anti-PD-1 (programmed death 1) therapy and radiotherapy on melanoma BM (brain metastasis). And the efficacy in the Chinese population is unclear. This study aimed to evaluate the efficacy of anti-PD-1 therapy and radiotherapy in Chinese melanoma patients with BM. We retrospectively reviewed 96 consecutive melanoma patients with BM treated at Sun Yat-Sen University Cancer Center. Patient demographics, BM characteristics and treatment details were carefully collected. The intracranial PFS (progression free survival) and OS (overall survival) were estimated using the Kaplan-Meier method. Twenty-five patients were treated with anti-PD-1 therapy and radiotherapy. Eighteen (72.0%) patients had SBRT (stereotactic body radiation therapy) or SRS (stereotactic radiosurgery) for BM, 1 (4.0%) patient had WBRT (whole brain radiation therapy), 6 (24.0%) patients had SBRT/SRS and WBRT. The median treatment period of anti-PD-1 therapy was 10.77 months. Objective intracranial response was observed in 15 (60%) patients, and 5 (20%) patients achieved CR (complete response). After a median follow-up of 16 months, 11 (44%) patients experienced intracranial PD (progressive disease), and 15 (60%) patients died. The median intracranial PFS and OS were 10.73 months (range, 1.67–38.83 months) and 15.87 months (range, 2.47–41.50 months), respectively. The 1-year intracranial PFS and OS were 61.9% (95% CI, 44.1–86.9%) and 62.5% (95%CI, 45.8–85.2%), respectively. Patients with BM can benefit from a combination of anti-PD-1 therapy and radiotherapy. It merits further investigation in melanoma patients with BM.