Safety and efficacy of nivolumab in patients with rare melanoma subtypes who progressed on or after ipilimumab treatment: a single-arm, open-label, phase II study (CheckMate 172)

Impact of Treatment Delay in Head and Neck Mucosal Melanoma on Overall Patient Survival

Objectives  Head and neck mucosal melanoma (HNMM) is a rare malignancy with high mortality. This study evaluates the impact of treatment delays on overall survival in HNMM. Design/Setting/Participants  A retrospective review of patients with surgically managed HNMM treated with adjuvant radiation was performed from the 2004-2016 National Cancer Database. Main Outcome Measures  Durations of diagnosis-to-treatment initiation (DTI), surgery-to-radiotherapy initiation (SRT), duration of radiotherapy (RTD), surgery-to-immunotherapy initiation (SIT), diagnosis-to-treatment end (DTE), and total treatment package (TTP) were calculated. Results  A total of 1,011 patients (50.7% female, 90.5% Caucasian) met inclusion criteria. Median DTI, SRT, RTD, SIT, DTE, and TTP were 30, 49, 41, 102, 119, and 87 days, respectively. Only longer DTE was associated with decreased mortality (hazard ratio, 0.720; 95% confidence interval, 0.536-0.965; p  = 0.028). Conclusion  DTI, SRT, RTD, SIT, and TTP do not significantly affect overall survival in patients with HNMM who undergo surgery and adjuvant radiation. Longer DTE is associated with improved survival in this population. Level of Evidence  4.

Project Optimus Elicits the "Holistic" Benefits of PK/PD Modeling of Immunotherapy

Leveraging a heterogeneous dataset, a recent article demonstrated the application of pharmacometric modeling to inform the dosing of nivolumab-relatlimab fixed-dose combination in special populations, including adolescents lacking clinical data. The use of model-informed approaches during clinical drug development can be cost-effective, which ensures fast access to drugs and enhances patient outcomes. See related article by Zhao et al., p. 3050.

Clinical Characteristics and Special Considerations in the Management of Rare Melanoma Subtypes

Rare histologic subtypes of melanoma, including acral, mucosal, uveal, and desmoplastic melanomas, only make up 5% of all diagnosed melanomas and are often underrepresented in large, randomized trials. Recent advancements in systemic therapy have shown marked improvement in pathologic response rates, improving progression-free and overall survival among cutaneous melanoma patients, but there are limited data to demonstrate improved survival among rarer subtypes of melanoma. Acral melanoma has a poor response to immunotherapy and is associated with worse survival. Mucosal melanoma has a large variability in its presentation, a poor prognosis, and a low mutational burden. Uveal melanoma is associated with a high rate of liver metastasis; recent adoption of infusion and perfusion therapies has demonstrated improved survival among these patients. Desmoplastic melanoma, a high-risk cutaneous melanoma, is associated with high locoregional recurrence rates and mutational burden, suggesting this melanoma may have enhanced response to immunotherapy. While these variants of melanoma represent distinct disease entities, this review highlights the clinicopathologic characteristics and treatment recommendations for each of these rare melanomas and highlights the utility of modern therapies for each of them.

Estimating scenarios for survival time in patients with advanced melanoma receiving immunotherapy and targeted therapy

BACKGROUND

We aim to provide survival scenario estimates for patients with advanced melanoma starting targeted therapies and immunotherapies.

MATERIALS AND METHODS

We sought randomized trials of targeted therapies and immunotherapies for advanced melanoma and recorded the following percentiles (represented survival scenario) from each overall survival (OS) curve: 90th (worst-case), 75th (lower-typical), 50th (median), 25th (upper-typical), and 10th (best-case). We tested whether these scenarios can be estimated for each OS curve by multiplying its median by 4 multiples: 0.25 (worst-case), 0.5 (lower-typical), 2 (upper-typical), and 3 (best-case).

RESULTS

We identified 15 trials with 8025 patients. For first-line combination targeted therapy treatment groups, the median (interquartile range, IQR) in months for each percentile was: 90th, 6.2 (6.0-6.5); 75th, 11.3 (11.3-11.4); and median, 24.4 (23.5-25.3). For the first-line combination immunotherapy treatment group, the percentiles in months were: 90th, 3.9 (2.8-4.5); 75th, 13.4 (10.1-15.4), median 73 (not applicable). In targeted therapy groups, simple multiples of the median OS were accurate for estimating the 90th percentile in 80%; 75th percentile in 40%; 25th percentile in 100%. In immunotherapy groups, these multiples were accurate at 0% for the 90th percentile, and 43% for the 75th percentile. The 90th percentile (worst-case scenario) was better estimated as 1/6× median OS, and the 75th percentile (lower-typical) as 1/3× median OS.

CONCLUSIONS

Simple multiples of the median OS are a useful framework to estimate scenarios for survival for patients receiving targeted therapies, not immunotherapy. Longer follow-up is required to estimate upper-typical and best-case scenarios.

Case report: Is severe toxicity the price to pay for high sensitivity to checkpoint inhibitors immunotherapy in desmoplastic melanoma?

Background

Desmoplastic melanoma (DM) is a rare subtype of melanoma characterized by high immunogenicity which makes it particularly suitable for immune checkpoint inhibitors (ICIs) treatment.

Case presentation

We report the case of a 53-year-old man with metastatic DM successfully treated with the combination of anti-CTLA-4 and anti-PD-1 antibodies, who developed serious immune-related adverse events (irAEs). The primary tumor was characterized by absent PD-L1 expression and no-brisk lymphocytes infiltration. NGS showed absence of BRAF mutation, a high tumor mutational burden, and an UV-induced DNA damage signature. Metastatic lesions regressed rapidly after few cycles of ICIs until complete response, however the patient developed serious irAEs including hypothyroidism, adrenal deficiency, and acute interstitial nephritis which led to the definitive suspension of treatment. Currently, the patient has normal renal functionality and no disease relapse after 26 months from starting immunotherapy, and after 9 months from its definitive suspension.

Conclusion

Efficacy and toxicity are two sides of the same coin of high sensitivity to ICIs in DM. For this reason, these patients should be closely monitored during ICIs therapy to promptly identify serious side effects and to correctly manage them.

A three-arm randomised phase II study of the MEK inhibitor selumetinib alone or in combination with paclitaxel in metastatic uveal melanoma

AIMS

The MAPK pathway is constitutively activated in uveal melanoma (UM). Selumetinib (AZD6244, ARRY-142886), a MEK inhibitor, has shown limited activity as monotherapy in metastatic UM. Pre-clinical studies support synergistic cytotoxic activity for MEK inhibitors combined with taxanes, and here we sought to assess the clinical efficacy of combining selumetinib and paclitaxel.

PATIENTS AND METHODS

Seventy-seven patients with metastatic UM who had not received prior chemotherapy were randomised to selumetinib alone, or combined with paclitaxel with or without interruption in selumetinib two days before paclitaxel. The primary endpoint was progression free survival (PFS). After amendment, the combination arms were combined for analysis and the sample size adjusted to detect a hazard ratio (HR): 0.55, 80% power at 1-sided 5% significance level.

RESULTS

The median PFS in the combination arms was 4.8 months (95% CI: 3.8 - 5.6) compared with 3.4 months (2.0 - 3.9) in the selumetinib arm (HR 0.62 [90% CI 0.41 - 0.92], 1-sided p-value = 0.022). ORR was 14% and 4% in the combination and monotherapy arms respectively. Median OS was 9 months for the combination and was not significantly different from selumetinib alone (10 months) with HR of 0.98 [90% CI 0.58 - 1.66], 1-sided p-value = 0.469. Toxicity was in keeping with the known profiles of the agents involved.

CONCLUSIONS

SelPac met its primary endpoint, demonstrating an improvement in PFS for combination selumetinib and paclitaxel. No improvement in OS was observed, and the modest improvement in PFS is not practice changing.

The Future of Checkpoint Inhibitors in Uveal Melanoma: A Narrative Review

INTRODUCTION

Immune checkpoint inhibitors have made tremendous progress over the last decade in the treatment of cutaneous melanoma, but their application in uveal melanoma treatment is less successful, owing in part to the immunological privilege of the eye and the liver, the most frequent site of metastasis. Nevertheless, the therapeutic outcomes reported currently are less pessimistic.

METHODS

In this review, we provide an overview of recent studies of immune checkpoint inhibitors in uveal melanoma and its metastasis and classify studies in this field into three groups: monotherapy of immune checkpoint inhibitors, dual-agent immune checkpoint inhibitors, and immune checkpoint inhibitors combined with other systemic or regional therapies.

RESULTS

Briefly, monotherapy with immune checkpoint inhibitors performed poorly. Dual-agent immune checkpoint inhibitors had slightly better outcomes than traditional treatments, especially in specific patient populations. As for the combination therapy, the combination with other systemic therapies did not show superiority over dual-agent immune checkpoint inhibitors, but combination with hepatic regional therapies was quite promising. Moreover, research on emerging checkpoints is currently limited to the stage of mechanistic studies.

CONCLUSION

We propose that immune checkpoint inhibitors remain alternative treatments for patients with uveal melanoma, but factors such as cost-effectiveness should also be taken into account. The combination therapy with immune checkpoint inhibitors deserves to be further explored.

Current State of Melanoma Therapy and Next Steps: Battling Therapeutic Resistance

Melanoma is the most aggressive and deadly form of skin cancer due to its high propensity to metastasize to distant organs. Significant progress has been made in the last few decades in melanoma therapeutics, most notably in targeted therapy and immunotherapy. These approaches have greatly improved treatment response outcomes; however, they remain limited in their abilities to hinder disease progression due, in part, to the onset of acquired resistance. In parallel, intrinsic resistance to therapy remains an issue to be resolved. In this review, we summarize currently available therapeutic options for melanoma treatment and focus on possible mechanisms that drive therapeutic resistance. A better understanding of therapy resistance will provide improved rational strategies to overcome these obstacles.

Immune checkpoint inhibitors for metastatic uveal melanoma: a meta-analysis

Several studies have evaluated immune checkpoint inhibitors (ICIs) for metastatic uveal melanoma; however, the efficacy of ICIs in the previous studies varied greatly. In this systematic review, we searched for prospective or retrospective studies on single or dual-ICIs for metastatic uveal melanoma treatment. A random-effect model meta-analysis with generic inverse-variance was conducted, and 36 articles representing 41 cohorts of 1414 patients with metastatic uveal melanoma were included. The pooled outcomes were as follows: objective response rate (ORR) was 5.6% (95% confidence interval [95%CI] 3.7-7.5%; I2, 36%), disease control rate (DCR) was 32.5% (95% CI 27.2-37.7%; I2, 73%), median progression-free survival was 2.8 months (95% CI 2.7-2.9 months; I2, 26%), and median overall survival (OS) was 11.2 months (95% CI 9.6-13.2 months; I2, 74%). Compared to single-agent ICI, dual ICI led to better ORR (single-agent: 3.4% [95% CI 1.8-5.1]; dual-agent: 12.4% [95% CI 8.0-16.9]; P < 0.001), DCR (single-agent: 29.3%, [95% CI 23.4-35.2]; dual-agent: 44.3% [95% CI 31.7-56.8]; P = 0.03), and OS (single-agent: 9.8 months [95% CI 8.0-12.2]; dual-agent: 16.3 months [95% CI 13.5-19.7]; P < 0.001). Our analysis provided treatment outcomes as described above. Dual-ICIs appear better than single-agent ICIs for the treatment of metastatic uveal melanoma.

Nilotinib in KIT-driven advanced melanoma: Results from the phase II single-arm NICAM trial

Mucosal (MM) and acral melanomas (AM) are rare melanoma subtypes of unmet clinical need; 15%-20% harbor KIT mutations potentially targeted by small-molecule inhibitors, but none yet approved in melanoma. This multicenter, single-arm Phase II trial (NICAM) investigates nilotinib safety and activity in KIT mutated metastatic MM and AM. KIT mutations are identified in 39/219 screened patients (18%); of 29/39 treated, 26 are evaluable for primary analysis. Six patients were alive and progression free at 6 months (local radiology review, 25%); 5/26 (19%) had objective response at 12 weeks; median OS was 7.7 months; ddPCR assay correctly identifies KIT alterations in circulating tumor DNA (ctDNA) in 16/17 patients. Nilotinib is active in KIT-mutant AM and MM, comparable to other KIT inhibitors, with demonstrable activity in nonhotspot KIT mutations, supporting broadening of KIT evaluation in AM and MM. Our results endorse further investigations of nilotinib for the treatment of KIT-mutated melanoma. This clinical trial was registered with ISRCTN (ISRCTN39058880) and EudraCT (2009-012945-49).

Optimal strategy in managing advanced melanoma

The advent of immune checkpoint inhibitors and combination therapy with BRAF inhibitors and MEK inhibitors has dramatically improved the prognosis of advanced melanoma. However, since acral melanoma and mucosal melanoma, which are rare in Western countries but are major subtypes of melanoma in East Asia, including Japan, have a low frequency of BRAF mutations, there are currently no treatment options other than immune checkpoint inhibitors in most such cases. Furthermore, owing to a lower tumor mutation burden, immune checkpoint inhibitors are less effective in acral and mucosal melanoma than in cutaneous melanoma. The aim of this review was to summarize the current status and future prospects for the treatment of advanced melanoma, comparing cutaneous melanoma, acral melanoma, and mucosal melanoma.

Multidisciplinary approach and treatment of acral and mucosal melanoma

Acral and mucosal melanoma are uncommon variants of melanoma. Acral melanoma has an age-adjusted incidence of approximately 1.8 cases per million individuals per year, accounting for about 2% to 3% of all melanoma cases. On the other hand, mucosal melanoma, with an incidence of 2.2 cases per million per year, makes up around 1.3% of all melanoma cases. These melanomas, in addition to being biologically and clinically distinct from cutaneous melanoma, share certain clinical and pathologic characteristics. These include a more aggressive nature and a less favorable prognosis. Furthermore, they exhibit a different mutational pattern, with KIT mutations being more prevalent in acral and mucosal melanomas. This divergence in mutational patterns may partially account for the relatively poorer prognosis, particularly to immune checkpoint inhibitors. This review explores various aspects of acral and mucosal melanoma, including their clinical presentation, pathologic features, mutational profiles, current therapeutic approaches, outcomes associated with systemic therapy, and potential strategies to address resistance to existing treatments.

Management of acral lentiginous melanoma: current updates and future directions

Acral lentiginous melanoma is a rare subtype of melanoma generally associated with poor outcomes, even when diagnosed at an early stage. The tumor genetic profile remains poorly understood, but it is known to have a suppressed immune environment compared to that of non-acral cutaneous melanomas, which limits therapy options. There is significant attention on the development of novel therapeutic approaches, although studies are limited due to disease rarity. For local disease, wide local excision remains the standard of care. Due to frequent under-staging on preoperative biopsy, wider margins and routine sentinel lymph node biopsy may be considered if morbidity would not be increased. For advanced disease, anti-PD1 monotherapy or combination therapy with anti-PD1 and anti-CTLA4 agents have been used as first-line treatment modalities. Anti-PD1 and anti-CTLA4 combination therapies have been shown to be particularly beneficial for patients with BRAF-mutant acral lentiginous melanoma. Other systemic combination regimens and targeted therapy options may be considered, although large studies with consistent results are lacking. Regional and intralesional therapies have shown promise for cutaneous melanomas, but studies generally have not reported results for specific histologic subtypes, especially for acral melanoma. Overall, the unique histologic and genetic characteristics of acral lentiginous melanoma make therapy options significantly more challenging. Furthermore, studies are limited, and data reporting has been inconsistent. However, more prospective studies are emerging, and alternative therapy pathways specific to acral lentiginous melanoma are being investigated. As further evidence is discovered, reliable treatment guidelines may be developed.

Novel cellular systems unveil mucosal melanoma initiating cells and a role for PI3K/Akt/mTOR pathway in mucosal melanoma fitness

BACKGROUND

Mucosal Melanomas (MM) are highly aggressive neoplasms arising from mucosal melanocytes. Current treatments offer a limited survival benefit for patients with advanced MM; moreover, the lack of pre-clinical cellular systems has significantly limited the understanding of their immunobiology.

METHODS

Five novel cell lines were obtained from patient-derived biopsies of MM arising in the sino-nasal mucosa and designated as SN-MM1-5. The morphology, ultrastructure and melanocytic identity of SN-MM cell lines were validated by transmission electron microscopy and immunohistochemistry. Moreover, in vivo tumorigenicity of SN-MM1-5 was tested by subcutaneous injection in NOD/SCID mice. Molecular characterization of SN-MM cell lines was performed by a mass-spectrometry proteomic approach, and their sensitivity to PI3K chemical inhibitor LY294002 was validated by Akt activation, measured by pAkt(Ser473) and pAkt(Thr308) in immunoblots, and MTS assay.

RESULTS

This study reports the validation and functional characterization of five newly generated SN-MM cell lines. Compared to the normal counterpart, the proteomic profile of SN-MM is consistent with transformed melanocytes showing a heterogeneous degree of melanocytic differentiation and activation of cancer-related pathways. All SN-MM cell lines resulted tumorigenic in vivo and display recurrent structural variants according to aCGH analysis. Of relevance, the microscopic analysis of the corresponding xenotransplants allowed the identification of clusters of MITF-/CDH1-/CDH2 + /ZEB1 + /CD271 + cells, supporting the existence of melanoma-initiating cells also in MM, as confirmed in clinical samples. In vitro, SN-MM cell lines were sensitive to cisplatin, but not to temozolomide. Moreover, the proteomic analysis of SN-MM cell lines revealed that RICTOR, a subunit of mTORC2 complex, is the most significantly activated upstream regulator, suggesting a relevant role for the PI3K-Akt-mTOR pathway in these neoplasms. Consistently, phosphorylation of NDRG1 and Akt activation was observed in SN-MM, the latter being constitutive and sustained by PTEN loss in SN-MM2 and SN-MM3. The cell viability impairment induced by LY294002 confirmed a functional role for the PI3K-Akt-mTOR pathway in SN-MM cell lines.

CONCLUSIONS

Overall, these novel and unique cellular systems represent relevant experimental tools for a better understanding of the biology of these neoplasms and, as an extension, to MM from other sites.

Tebentafusp as a Promising Drug for the Treatment of Uveal Melanoma

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults and commonly occurs in the Caucasian population. The malignancy involves the uvea of the eye, which includes the iris, ciliary body, and choroid. The etiology of UM is still not well understood, but age is a risk factor. Symptoms include blurred vision, redness of the eye, floaters, dark spots, a change in the size of the pupil, and loss of vision. The location, shape, and size of the tumor are important for therapeutic purposes. Treating metastasis is always a challenge in UM cases. In cases of lung metastasis, the survival rate decreases. Treatment includes surgery, laser therapy, immunotherapy, hormone therapy, and chemotherapy. Recently, in 2022, the United States Food and Drug Administration (FDA) approved the drug tebentafusp. Tebentafusp was developed to target the most common HLA complex in humans. The present review discusses the indications for the use of a new drug tebentafusp, its mechanism of action, dose, pharmacokinetics, results of clinical trials conducted, and adverse effects like cytokine release syndrome. Hence, tebentafusp is the first T cell receptor (TCR) therapeutic drug that could be considered for the treatment of UM.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of melanoma, version 3.0

Since the first approval for immune checkpoint inhibitors (ICIs) for the treatment of cutaneous melanoma more than a decade ago, immunotherapy has completely transformed the treatment landscape of this chemotherapy-resistant disease. Combination regimens including ICIs directed against programmed cell death protein 1 (PD-1) with anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) agents or, more recently, anti-lymphocyte-activation gene 3 (LAG-3) agents, have gained regulatory approvals for the treatment of metastatic cutaneous melanoma, with long-term follow-up data suggesting the possibility of cure for some patients with advanced disease. In the resectable setting, adjuvant ICIs prolong recurrence-free survival, and neoadjuvant strategies are an active area of investigation. Other immunotherapy strategies, such as oncolytic virotherapy for injectable cutaneous melanoma and bispecific T-cell engager therapy for HLA-A*02:01 genotype-positive uveal melanoma, are also available to patients. Despite the remarkable efficacy of these regimens for many patients with cutaneous melanoma, traditional immunotherapy biomarkers (ie, programmed death-ligand 1 expression, tumor mutational burden, T-cell infiltrate and/or microsatellite stability) have failed to reliably predict response. Furthermore, ICIs are associated with unique toxicity profiles, particularly for the highly active combination of anti-PD-1 plus anti-CTLA-4 agents. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to develop this clinical practice guideline on immunotherapy for the treatment of melanoma, including rare subtypes of the disease (eg, uveal, mucosal), with the goal of improving patient care by providing guidance to the oncology community. Drawing from published data and clinical experience, the Expert Panel developed evidence- and consensus-based recommendations for healthcare professionals using immunotherapy to treat melanoma, with topics including therapy selection in the advanced and perioperative settings, intratumoral immunotherapy, when to use immunotherapy for patients with BRAFV600-mutated disease, management of patients with brain metastases, evaluation of treatment response, special patient populations, patient education, quality of life, and survivorship, among others.

Efficacy of immune checkpoint inhibition in metastatic uveal melanoma: a systematic review and meta-analysis

Metastatic uveal melanoma (mUM) has historically been associated with short survival and limited effective treatments. Immune checkpoint inhibitors (ICIs) have been trialed in mUM; however, robust conclusions regarding their efficacy are difficult to draw given small study sizes and heterogeneous patient populations. Five databases were searched using a combination of 'ICI' and 'mUM' headings, and data on patient demographics, objective response rate (ORR), overall survival (OS) and progression-free survival (PFS) were extracted. Pooled ORR was calculated using a random effects model and the inverse variance method. Available Kaplan-Meier OS and PFS curves were used to construct summary OS and PFS plots, from which median values were derived. Pooled ORR was 9.2% overall (95% CI 7.2-11.8) [4.1% for anti-CTLA4 (95% CI 2.1-7.7), 7.1% for anti-PD(L)1 (95% CI 4.5-10.9) and 13.5% for anti-CTLA4 plus anti-PD1 (95% CI 10.0-18.0)]. Median OS was 11.5 months overall (95% CI 9.5-13.8) [8.0 months for anti-CTLA4 (95% CI 5.5-9.9), 11.7 months for anti-PD(L)1 (95% CI 9.0-14.0) and 16.0 months for ipilimumab plus anti-PD1 (95% CI 11.5-17.7) ( P < 0.001)]. Median PFS was 3.0 months overall (95% CI 2.9-3.1). ICIs have limited efficacy in mUM and a recommendation for their use must consider the balance of benefit and risk for individual patients if no other options are available. Further biomarker profiling studies may be helpful in assessing which patients will benefit from ICIs, in particular the addition of ipilimumab to anti-PD1 therapy.

SALVO: Single-Arm Trial of Ipilimumab and Nivolumab as Adjuvant Therapy for Resected Mucosal Melanoma

PURPOSE

Mucosal melanoma is a rare, aggressive form of melanoma with extremely high recurrence rates despite definitive surgical resection with curative intent. Currently there is no consensus on adjuvant therapy. Data on checkpoint inhibitors for adjuvant therapy are lacking.

PATIENTS AND METHODS

We performed a single-arm, multicenter clinical trial using "flip dose" ipilimumab (1 mg/kg q3w × 4 cycles), and nivolumab (3 mg/kg q3w × 4 cycles), then nivolumab 480 mg q4w × 11 cycles to complete a year of adjuvant therapy. Participants must have had R0/R1 resection ≤90 days before registration, no prior systemic therapy (adjuvant radiotherapy allowed), ECOG 0/1, and no uncontrolled autoimmune disease or other invasive cancer. Patients were recruited through the Midwest Melanoma Partnership/Hoosier Oncology Network.

RESULTS

From September 2017 to August 2021, 35 patients were enrolled. Of these, 29 (83%) had R0 resections, and 7 (20%) received adjuvant radiotherapy. Median age was 67 years, 21 (60.0%) female. Recurrence-free survival (RFS) rates at 1 and 2 years were 50% [95% confidence interval (CI), 31%-66%] and 37% (95% CI, 19%-55%), respectively. Overall survival rates at 1 and 2 years were 87% (95% CI, 68%-95%) and 68% (95% CI, 46%-83%), respectively. Median RFS was 10.3 months (95% CI, 5.7-25.8). Most common grade 3 toxicities were diarrhea (14%), hypertension (14%), and hyponatremia (11%), with no grade 4/5 toxicities.

CONCLUSIONS

Flip-dose ipilimumab and nivolumab after resection of mucosal melanoma is associated with outcomes improved over that of surgical resection alone. Long-term follow-up, subgroup analyses and correlative studies are ongoing.

Nail Apparatus Melanoma: Current Management and Future Perspectives

Nail apparatus melanoma (NAM) is a rare type of cutaneous melanoma that belongs to the acral melanoma subtype. NAM is managed principally in accordance with the general treatment for cutaneous melanoma, but there is scarce evidence in support of this in the literature. Acral melanoma is genetically different from non-acral cutaneous melanoma, while recently accumulated data suggest that NAM also has a different genetic background from acral melanoma. In this review, we focus on recent advances in the management of NAM. Localized NAM should be surgically removed; amputation of the digit and digit-preserving surgery have been reported. Sentinel lymph node biopsy can be considered for invasive NAM for the purpose of accurate staging. However, it is yet to be clarified whether patients with metastatic sentinel lymph nodes can be safely spared completion lymph node dissection. Similar to cutaneous melanoma, immune checkpoint inhibitors and BRAF/MEK inhibitors are used as the first-line treatment for metastatic NAM, but data on the efficacy of these therapies remain scarce. The therapeutic effects of immune checkpoint inhibitors could be lower for NAM than for cutaneous melanoma. This review highlights the urgent need to accumulate data to better define the optimal management of this rare melanoma.

Immune checkpoint inhibitor-based therapy for advanced acral and mucosal melanoma

Acral melanoma (AM) and mucosal melanomas (MM) are rare clinical subtypes of melanoma. AM and MM are etiologically, biologically, and molecularly distinct from cutaneous melanoma (CM). Despite the recent development of immune checkpoint inhibitors (ICIs) for the treatment of advanced CMs, the true therapeutic efficacy of ICIs for these rare subtypes remains unclear. Since these subtypes are rare, especially in the Caucasian population, their biological features and corresponding novel therapies are underexplored than those of CM. Even in the larger phase III clinical trials for ICIs, the sample size of patients with AM and MM is limited. Consequently, establishment of standard of care for advanced AM and MM has been challenging. This review covers current update and overview on clinical efficacy of ICIs and ICI-based therapy for advanced AM and MM, based mainly on the reported clinical trials, prospective observational studies, and retrospective studies, to provide a better understanding of the current landscape of this field. In addition, we discuss the future direction of treatment for those rare clinical subtypes, focusing on issues relevant to dermatology and medical oncology.

The NLRP3 inflammasome - interleukin 1β axis in uveal melanoma

Uveal melanoma (UM) is the most common primary intraocular cancer in the adult population. Recent studies suggested that the NLRP3 inflammasome could be a therapeutic target for cutaneous melanoma (CM), but the role of NLRP3 in UM remains unknown. Here, we analyzed the NLRP3-IL-1β axis in 5 UM and 4 CM cell lines. Expression of NLRP3 mRNA in UM and CM was low, and expression in UM was lower than in CM (P < 0.001). NLRP3 protein levels were below detection limit for all cell lines. UM exhibited lower baseline IL-1β secretion than CM, especially when compared to the Hs294t cell line (P < 0.05). Bioinformatic analysis of human tumor samples showed that UM has significantly lower expression of NLRP3 and IL-1β compared with CM. In conclusion, our work shows evidence of extremely low NLRP3 expression and IL-1β secretion by melanoma cells and highlight differences between CM and UM.

Efficacy comparison between anti-PD-1 antibody monotherapy and anti-PD-1 plus anti-CTLA-4 combination therapy as first-line immunotherapy for advanced acral melanoma: A retrospective, multicenter study of 254 Japanese patients

BACKGROUND

Although anti-PD-1 antibody monotherapy (PD-1) is commonly used to treat advanced acral melanoma (AM), its efficacy is limited. Further, data on the efficacy of PD-1 plus anti-CTLA-4 antibody (PD-1+CTLA-4) for the treatment of AM are limited. Therefore, we compared the efficacy of PD-1+CTLA-4 and PD-1 in the treatment of Japanese patients with advanced AM.

METHODS

This retrospective study evaluated patients with advanced AM who were treated with PD-1 or PD-1+CTLA-4 as first-line immunotherapy in 24 Japanese institutions between 2014 and 2020. Treatment efficacy focussing on the objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) was compared between the two groups.

RESULTS

In total, 254 patients (palm and sole melanoma [PSM], n = 180; nail apparatus melanoma [NAM], n = 74) were included. Among the patients with PSM, the ORR (19% vs. 31%; P = 0.44), PFS (5.9 vs. 3.2 months; P = 0.74), and OS (23.1 vs. not reached; P = 0.55) did not differ significantly between the PD-1 and PD-1+CTLA-4 groups. Among the patients with NAM, the ORR (61% vs. 10%; P < 0.001) was significantly higher and PFS was longer (6.4 vs. 3.8 months; P = 0.10) in the PD-1+CTLA-4 group than in the PD-1 group. Cox multivariate analysis demonstrated that PD-1+CTLA-4 is an independent predictor of a favourable PFS in patients with NAM (P = 0.002).

CONCLUSIONS

The efficacy of PD-1+CTLA-4 is not superior to that of PD-1 for the treatment of advanced PSM. However, PD-1+CTLA-4 may be more efficacious than PD-1 for the treatment of advanced NAM.

Advanced Acral Melanoma Therapies: Current Status and Future Directions

Melanoma is one of the deadliest malignancies. Its incidence has been significantly increasing in most countries in recent decades. Acral melanoma (AM), a peculiar subgroup of melanoma occurring on the palms, soles, and nails, is the main subtype of melanoma in people of color and is extremely rare in Caucasians. Although great progress has been made in melanoma treatment in recent years, patients with AM have shown limited benefit from current therapies and thus consequently have worse overall survival rates. Achieving durable therapeutic responses in this high-risk melanoma subtype represents one of the greatest challenges in the field. The frequency of BRAF mutations in AM is much lower than that in cutaneous melanoma, which prevents most AM patients from receiving treatment with BRAF inhibitors. However, AM has more frequent mutations such as KIT and CDK4/6, so targeted therapy may still improve the survival of some AM patients in the future. AM may be less susceptible to immune checkpoint inhibitors because of the poor immunogenicity. Therefore, how to enhance the immune response to the tumor cells may be the key to the application of immune checkpoint inhibitors in advanced AM. Anti-angiogenic drugs, albumin paclitaxel, or interferons are thought to enhance the effectiveness of immune checkpoint inhibitors. Combination therapies based on the backbone of PD-1 are more likely to provide greater clinical benefits. Understanding the molecular landscapes and immune microenvironment of AM will help optimize our combinatory strategies.

Management of Acral and Mucosal Melanoma: Medical Oncology Perspective

Acral and mucosal melanomas (MM) are rare subtypes of melanoma that are biologically and clinically distinct from cutaneous melanoma. Despite the progress in the treatment of cutaneous melanomas with the development of targeted and immune therapies, the therapeutic options for these less common subtypes remain limited. Difficulties in early diagnosis, the aggressive nature of the disease, and the frequently occult sites of origin have also contributed to the poor prognosis associated with acral and MM, with substantially worse long-term prognosis. The rarity of these subtypes has posed significant barriers to better understanding their biological features and investigating novel therapies. Consequently, establishing standardized treatment guidelines has been a challenge. In this review, we provide a brief overview of the current knowledge regarding acral and MM, focusing on their epidemiology, genetic backgrounds, and unique clinical characteristics. Further discussion centers around the management of primary and advanced disease and the role of emerging targeted and immune therapies for these subtypes, specifically focusing on issues relevant to medical oncologists.

The pharmacotherapeutic management of nail unit and acral melanomas

INTRODUCTION

Acral and nail unit melanomas are rare subtypes of melanoma, which have poor prognoses. Current guidelines for optimal treatment are lacking. Recent clinical trials have evaluated new pharmacotherapeutic agents for melanoma treatment, with dramatically improved survival rates; however, studies on acral and nail unit melanomas are limited in comparison to trials on cutaneous melanoma.

AREAS COVERED

This is a comprehensive review of the literature regarding the available treatment options for acral and nail unit melanomas, with consideration of safety and tolerability.

EXPERT OPINION

Programmed cell death protein 1 inhibitors are more efficacious than cytotoxic T lymphocyte-associated antigen-4 blockers in acral and nail unit melanomas, although both are well-tolerated. Tyrosine kinase inhibitors have good clinical activity, however, data on safety is relatively limited. There is minimal data on high dose interferon α-2b and cyclin-dependent kinase 4 and 6 inhibitors, and efficacy and safety must be evaluated in future trials before they can be recommended for use in this patient population. Prospective clinical trials on acral and nail unit melanomas are lacking, and must be performed in large patient populations, with international collaboration likely necessary in order to enroll adequate participants.

Radiotherapy and Immunotherapy, Combined Treatment for Unresectable Mucosal Melanoma with Vaginal Origin

Gynecologic melanomas are uncommon and malignant mucosal melanomas with vaginal origin are extremely rare, treatment strategies are limited and extrapolated from those of cutaneous melanoma. A better understanding of the vulvovaginal melanoma’s biology and its risk factors is needed. Therapeutic strategies include surgery, systemic therapy and radiotherapy. For vulvovaginal melanoma, surgery is selected as the primary treatment. Immunotherapy and target treatment have recently enhanced the systemic therapy for cutaneous melanoma (CM). Immunotherapy and new target agents demonstrated a better survival of melanoma and might be considered as treatment of vulvovaginal melanoma. Radiotherapy is included in the therapeutic arsenal for mucosal melanoma and may be performed on selected patients who may receive concurrent checkpoints and inhibition neoadjuvant radiotherapy with the purpose of reducing morbidity and mortality.

Response to immune checkpoint inhibitors in acral melanoma: A nationwide cohort study

BACKGROUND

Recent reports suggest the limited efficacy of immune checkpoints inhibitors in advanced acral melanoma (AM). This study aims to investigate the clinical outcomes of immune checkpoint inhibitors in patients with stage III and IV AM and compare them to cutaneous melanoma (CM).

METHODS

We included patients with advanced AM and CM treated with first-line anti-programmed cell death (PD)-1 monotherapy or ipilimumab-nivolumab registered in the prospective nationwide Dutch Melanoma Treatment Registry. Objective response rates, progression-free survival (PFS) and overall survival (OS) were calculated. A Cox proportional hazard model was used to assess the prognostic factors with PFS and OS.

RESULTS

In total, 2058 patients (88 AM and 1970 CM) with advanced melanoma were included. First-line objective response rates were 34% for AM versus 54% for CM in the advanced anti-PD-1 cohort and 33% for AM versus 53% for CM in the advanced ipilimumab-nivolumab cohort. The Median PFS was significantly shorter for anti-PD-1 treated AM patients (3.1 months; 95%CI: 2.8-5.6) than patients with CM (10.1 months; 95%CI: 8.5-12.2) (P < 0.001). In patients with advanced melanoma, AM was significantly associated with a higher risk of progression (HRadj 1.63; 95%CI: 1.26-2.11; P < 0.001) and death (HRadj 1.54; 95%CI: 1.15-2.06; P = 0.004) than CM.

CONCLUSIONS

This study shows lower effectiveness of anti-PD -1 monotherapy and ipilimumab-nivolumab in AM, with lower response rates, PFS and OS than CM. This group of patients should be prioritised in the development of alternative treatment strategies.

Molecular Profiling and Novel Therapeutic Strategies for Mucosal Melanoma: A Comprehensive Review

Mucosal melanoma is a rare and aggressive subtype of melanoma. Unlike its cutaneous counterpart, mucosal melanoma has only gained limited benefit from novel treatment approaches due to the lack of actionable driver mutations and poor response to immunotherapy. Over the last years, whole-genome and exome sequencing techniques have led to increased knowledge on the molecular landscape of mucosal melanoma. Molecular studies have underlined noteworthy findings with potential therapeutic implications, including the presence of KIT mutations, which are potential targets of tyrosine kinase inhibitors currently in use in the clinic (imatinib), but also SF3B1 mutation, CDK4 amplifications, and CDKN2A gene deletions, which are presently under investigation in clinical trials. Recent results from a pooled analysis of patients with mucosal melanoma treated with immunotherapy have suggested that the combination of immune checkpoint inhibitors might improve survival outcomes in this subset of patients, as compared with single-agent immunotherapy. However, these results are not confirmed across different studies, and combo-immunotherapy correlates with a higher rate of adverse events. In this review, we describe the clinical, biological, and genetic features of mucosal melanoma. We also provide an update on the results of approved systemic treatment in this setting and overview the therapeutic strategies currently under investigation in clinical trials.

Gp-100 as a Novel Therapeutic Target in Uveal Melanoma

Simple Summary

Glycoprotein 100 (Gp-100) is a protein highly expressed in melanoma tissue that has recently been effectively targeted by tebentafusp, a first-in-class bispecific protein of the immune-mobilizing monoclonal T cell receptors against cancer (ImmTACs) family. Recently, a randomized phase III trial reported an overall survival benefit for tebentafusp in patients with untreated metastatic uveal melanoma.

Abstract

Uveal melanoma is a rare neoplasm with poor prognosis in the metastatic setting. Unlike cutaneous melanoma, treatment with kinase inhibitors or immune checkpoint inhibitors is not effective. Glycoprotein 100 (Gp-100) is a protein highly expressed in melanocytes and melanoma that has recently been effectively targeted by tebentafusp, a first-in-class bispecific protein of the immune-mobilizing monoclonal T cell receptors against cancer (ImmTACs) family. Tebentafusp targets tumor cells that express a peptide of Gp-100 presented by HLA*A0201, creating an immune synapse that kills targeted tumor cells. Recently, a randomized phase III trial reported an overall survival benefit for tebentafusp in patients with untreated metastatic uveal melanoma. The aim of this comprehensive review is to summarize evidence of Gp-100 as a therapeutic target in melanoma, and the preclinical and clinical development of tebentafusp as a novel therapeutic strategy for patients with uveal melanoma.

Efficacy of Immune Checkpoint Inhibitors in Rare Tumours: A Systematic Review

Background

Rare cancers, as defined by the European Union, occur in fewer than 15 out of 100,000 people each year. The International Rare Cancer Consortium defines rare cancer incidence as less than six per 100,000 per year. There is a growing number of reports of the efficacy of immune checkpoint inhibitor (ICI) therapy in patients with rare tumours, and hence, we conducted a comprehensive review to summarise and analyse the available literature.

Methods

A literature search of PubMed was performed on January 31, 2021, using the following ICI names as keywords: ipilimumab, tremelimumab, cemiplimab, nivolumab, pembrolizumab, avelumab, atezolizumab, and durvalumab. Studies on patients with rare tumours who were being treated with ICIs were included. We plotted the overall response rate against the corresponding median survival across a variety of cancer types using linear regression.

Results

From 1,255 publications retrieved during the primary search, 62 publications were selected (with a total of 4,620 patients). Only four were randomised trials. A minority were first-line studies, while the remaining were studies in which ICIs were delivered as salvage therapy in pretreated patients. There was a good correlation between response rate and overall survival (Spearman R2 >0.9) in skin cancers, mesothelioma, and sarcomas.

Conclusions

Treatment of advanced-stage rare tumours with ICI therapy was found to be associated with significant activity in some orphan diseases (e.g., Merkel cell carcinoma) and hepatocellular carcinoma. Several ongoing prospective clinical trials will expand the knowledge on the safety and efficacy of ICI therapy in patients with these rare cancers.

Systemic and liver-directed therapies in metastatic uveal melanoma: state-of-the-art and novel perspectives

Metastatic uveal melanoma (MUM) is the most common form of noncutaneous melanoma. It is different from its cutaneous counterpart and is characterized by a very poor prognosis. Despite groundbreaking improvements in the treatment of cutaneous melanoma, there have been few advances in the treatment of MUM, and standard treatments for MUM have not been defined. We performed a systematic review focusing our attention on all interventional studies, ongoing or already published, concerning the treatment of MUM. We present results from studies of chemotherapy, targeted therapy, immunotherapy and liver-directed therapies. Although the results in this setting have been disappointing until now, trials investigating novel immunotherapeutic strategies alone and in combination with targeted agents and liver-directed therapies are ongoing.

Rechallenge of immune checkpoint inhibitors: A systematic review and meta-analysis

BACKGROUND

The role of immune checkpoint inhibitors (ICI) rechallenge in cancer patients is not defined. When ICIs are discontinued due to treatment completion or toxicity, another course of ICIs is feasible in clinical practice, but the amount of data is still quite limited to draw definitive conclusions. Here we report the results of a meta-analysis evaluating efficacy and safety of ICI rechallenge.

METHODS

PubMed, Embase, and Cochrane library were searched for studies reporting efficacy and safety of ICI rechallenge. Pooled analysis of response rate (ORR), median progression-free survival (mPFS) and median overall survival (mOS) were calculated.

RESULTS

A total of 49 studies were included in qualitative and quantitative pooled analysis Overall response rate, mPFS and mOS were 21.8 % (range 0-70 %), 4.9 months (range 0-19.1 months) and 15.6 months (range 5.1-39 months), respectively. Incidence of any grade and grade 3-4 adverse events were 52.2 % (range 4-100 %) and 21.5 % (range 0-97.8 %), respectively. In the subgroup of patients who had previously discontinued ICI because of disease progression ORR, mPFS and mOS were 15.2 %, 2.9 and 7.9 months. Patients who had previously discontinued ICI because of toxicity achieved an ORR of 44 % and a mPFS of 13.2 months with the rechallenge.

CONCLUSIONS

Our results suggest that rechallenge ICI is an active and feasible strategy, and it could be considered on an individual basis. However, this analysis is based on non-randomized studies. Prospective studies are needed to clarify the role of rechallenge after disease progression or adverse events.

Development of a Metastatic Uveal Melanoma Prognostic Score (MUMPS) for Use in Patients Receiving Immune Checkpoint Inhibitors

Simple Summary

This is a retrospective cohort study of metastatic uveal melanoma patients. This study undertook to identify clinical characteristics that were predictive and prognostics of benefit to immune checkpoint inhibitors in patients with metastatic uveal melanoma. We developed a Metastatic Uveal Melanoma Prognostic risk Score based on retrospective data that is comprised of 3 readily available clinical variables (time to metastatic diagnosis, presence of bone metastases, and LDH). Our findings demonstrated that the Metastatic Uveal Melanoma Prognostic risk Score was associated with a statistically significant association with overall survival outcomes in patients with metastatic uveal melanoma treated with ICI. There was a significant predictive association with disease control to ICI for patients with a ‘good risk’ Metastatic Uveal Melanoma Prognostic risk score. This is one of the larger analysis of clinical outcomes in metastatic uveal melanoma patients to date and could inform clinical decision-making.

Abstract

Metastatic uveal melanoma (mUM) is a rare disease. There are limited data on prognostic clinical factors for overall survival (OS) in patients with mUM treated with immune checkpoint inhibitors (ICI). Retrospective and non-randomized prospective studies have reported response rates of 0–17% for anti-PD1/L1 ± anti-CTLA4 ICI in mUM, indicating a potential benefit only in a subset of patients. This study evaluates the characteristics associated with ICI benefit in patients with mUM. We performed a single-center retrospective cohort study of patients with mUM who received anti-PD1/L1 ± anti-CTLA4 ICI between 2014–2019. Clinical and genomic characteristics were collected from a chart review. Treatment response and clinical progression were determined by physician assessment. Multivariable Cox regression models and Kaplan–Meier log-rank tests were used to assess differences in clinical progression-free survival (cPFS) and OS between groups and identify clinical variables associated with ICI outcomes. We identified 71 mUM patients who received 75 lines of ICI therapy. Of these, 54 received anti-PD1/L1 alone, and 21 received anti-PD1/L1 + anti-CTLA4. Patient characteristics were: 53% female, 48% were 65 or older, 72% received one or fewer lines of prior therapy. Within our cohort, 53% of patients had developed metastatic disease <2 years after their initial diagnosis. Bone metastases were present in 12% of patients. The median cPFS was 2.7 months, and the median OS was 10.0 months. In multivariable analyses for both cPFS and OS, the following variables were associated with a good prognosis: ≥2 years from the initial diagnosis to metastatic disease (n = 25), LDH < 1.5 × ULN (n = 45), and absence of bone metastases (n = 66). We developed a Metastatic Uveal Melanoma Prognostic Score (MUMPS). Patients were divided into 3 MUMPS groups based on the number of the above-mentioned prognostic variables: Poor prognosis (0–1), Intermediate prognosis (2) and Good prognosis (3). Good prognosis patients experienced longer cPFS (6.0 months) and OS (34.5 months) than patients with intermediate (2.3 months cPFS, 9.4 months OS) and poor prognosis disease (1.8 months cPFS, 3.9 months OS); p < 0.0001. We developed MUMPS—a prognostic score based on retrospective data that is comprised of 3 readily available clinical variables (time to metastatic diagnosis, presence of bone metastases, and LDH). This MUMPS score has a potential prognostic value. Further validation in independent datasets is warranted to determine the role of this MUMPS score in selecting ICI treatment management for mUM.

Electronic patient-reported outcomes and machine learning in predicting immune-related adverse events of immune checkpoint inhibitor therapies

BACKGROUND

Immune-checkpoint inhibitors (ICIs) have introduced novel immune-related adverse events (irAEs), arising from various organ systems without strong timely dependency on therapy dosing. Early detection of irAEs could result in improved toxicity profile and quality of life. Symptom data collected by electronic (e) patient-reported outcomes (PRO) could be used as an input for machine learning (ML) based prediction models for the early detection of irAEs.

METHODS

The utilized dataset consisted of two data sources. The first dataset consisted of 820 completed symptom questionnaires from 34 ICI treated advanced cancer patients, including 18 monitored symptoms collected using the Kaiku Health digital platform. The second dataset included prospectively collected irAE data, Common Terminology Criteria for Adverse Events (CTCAE) class, and the severity of 26 irAEs. The ML models were built using extreme gradient boosting algorithms. The first model was trained to detect the presence and the second the onset of irAEs.

RESULTS

The model trained to predict the presence of irAEs had an excellent performance based on four metrics: accuracy score 0.97, Area Under the Curve (AUC) value 0.99, F1-score 0.94 and Matthew's correlation coefficient (MCC) 0.92. The prediction of the irAE onset was more difficult with accuracy score 0.96, AUC value 0.93, F1-score 0.66 and MCC 0.64 but the model performance was still at a good level.

CONCLUSION

The current study suggests that ML based prediction models, using ePRO data as an input, can predict the presence and onset of irAEs with a high accuracy, indicating that ePRO follow-up with ML algorithms could facilitate the detection of irAEs in ICI-treated cancer patients. The results should be validated with a larger dataset. Trial registration Clinical Trials Register (NCT3928938), registration date the 26th of April, 2019.

Current Status and Prospects of Immunotherapy for Gynecologic Melanoma

Gynecologic melanomas are rare and have a poor prognosis. Although immunotherapy (immune checkpoint inhibitors) and targeted therapy has greatly improved the systemic treatment of cutaneous melanoma (CM) in recent years, its efficacy in gynecologic melanomas remains uncertain because of the rarity of this malignancy and its scarce literature. This review aimed to evaluate the literature of gynecologic melanomas treated with immunotherapy and targeted therapy through a PubMed search. We identified one study focusing on the overall survival of gynecologic melanomas separately and five case series and nine case reports concentrating on gynecologic melanomas treated with an immune checkpoint inhibitor and/or targeted therapy. Furthermore, the KIT mutation has the highest rate among all mutations in mucosal melanoma types. The KIT inhibitors (Tyrosine kinase inhibitors: TKIs) imatinib and nilotinib could be the treatment options. Moreover, immune checkpoint inhibitors combined with KIT inhibitors may potentially treat cases of resistance to immune checkpoint inhibitors. However, because of the different conditions and a small number of cases, it is difficult to evaluate the efficacy of immunotherapy and targeted therapy for gynecologic melanoma rigorously at this time. Further prospective cohort or randomized trials of gynecologic melanoma alone are needed to assess the treatment with solid evidence.

Hypoxia-dependent drivers of melanoma progression

Hypoxia, a condition of low oxygen availability, is a hallmark of tumour microenvironment and promotes cancer progression and resistance to therapy. Many studies reported the essential role of hypoxia in regulating invasiveness, angiogenesis, vasculogenic mimicry and response to therapy in melanoma. Melanoma is an aggressive cancer originating from melanocytes located in the skin (cutaneous melanoma), in the uveal tract of the eye (uveal melanoma) or in mucosal membranes (mucosal melanoma). These three subtypes of melanoma represent distinct neoplasms in terms of biology, epidemiology, aetiology, molecular profile and clinical features.In this review, the latest progress in hypoxia-regulated pathways involved in the development and progression of all melanoma subtypes were discussed. We also summarized current knowledge on preclinical studies with drugs targeting Hypoxia-Inducible Factor-1, angiogenesis or vasculogenic mimicry. Finally, we described available evidence on clinical studies investigating the use of Hypoxia-Inducible Factor-1 inhibitors or antiangiogenic drugs, alone or in combination with other strategies, in metastatic and adjuvant settings of cutaneous, uveal and mucosal melanoma.Hypoxia-Inducible Factor-independent pathways have been also reported to regulate melanoma progression, but this issue is beyond the scope of this review.As evident from the numerous studies discussed in this review, the increasing knowledge of hypoxia-regulated pathways in melanoma progression and the promising results obtained from novel antiangiogenic therapies, could offer new perspectives in clinical practice in order to improve survival outcomes of melanoma patients.

Immune Checkpoint Inhibitor Associated Hepatotoxicity in Primary Liver Cancer Versus Other Cancers: A Systematic Review and Meta-Analysis

BACKGROUND

Overall risks of hepatotoxicity with immune checkpoint inhibitors (ICIs) have yet to be compared in primary liver cancers to other solid tumors.

METHODS

We reviewed data from the PubMed, Embase, and Scopus databases, and assessed the risk of hepatotoxicity associated with ICIs.

RESULTS

A total of 117 trials were eligible for the meta-analysis, including 7 trials with primary liver cancers. The most common hepatotoxicity was ALT elevation (incidence of all grade 5.29%, 95% CI 4.52-6.20) and AST elevation (incidence of all grade 5.88%, 95% CI 4.96-6.97). The incidence of all grade ALT and AST elevation was 6.01% and 6.84% for anti-PD-1 (95% CI 5.04-7.18/5.69-8.25) and 3.60% and 3.72% for anti-PD-L1 (95% CI 2.72-4.76/2.82-4.94; p< 0.001/p<0.001). The incidence of ≥ grade 3 ALT and AST elevation was 1.54% and 1.48% for anti-PD-1 (95% CI 1.19-1.58/1.07-2.04) and 1.03% and 1.08% for anti-PD-L1 (95% CI 0.71-1.51/0.80-1.45; p= 0.002/p<0.001). The incidence of all grade ALT and AST elevation was 13.3% and 14.2% in primary liver cancers (95% CI 11.1-16.0 and 9.93-20.36) vs. 4.92% and 5.38% in other solid tumors (95% CI 4.21-5.76 and 4.52-5.76 in other solid tumors; p <0.001/p<0.001).

CONCLUSION

Our study indicates that anti-PD-1 is associated with a higher risk of all- and high-grade hepatotoxicity compared to anti-PD-L1, and primary liver cancers are associated with a higher risk of all- and high-grade hepatotoxicity compared to other solid tumors.

The efficacy of anti-programmed cell death protein 1 therapy among patients with metastatic acral and metastatic mucosal melanoma

Background

Anti‐programmed cell death protein 1 (PD‐1) antibodies are a standard treatment for metastatic melanoma patients. However, the understanding of the efficacy of anti‐PD‐1 for acral melanoma (AM) and mucosal melanoma (MM) is limited as these subtypes are relatively rare compared to cutaneous melanoma (CM).

Methods

This single institution, retrospective cohort study included patients with advanced AM and MM who underwent anti‐PD‐1 therapy for metastatic melanoma between 2012 and 2018. Objective responses were determined using the investigator‐assessed Response Evaluation Criteria in Solid Tumors version 1.1. Progression‐free survival (PFS) and overall survival (OS) were assessed using the Kaplan–Meier method. A Cox regression analysis was performed to identify the factors associated with survival outcomes.

Results

Ninety‐seven patients were identified, 38 (39%) with AM and 59 (61%) with MM. The objective response rates (ORRs) were 21.0% and 15.2% in patients with AM and MM, respectively. The median PFS and OS were 3.6 and 25.7 months for AM patients, and 3.0 and 20.1 months for MM patients, respectively. Elevated serum lactate dehydrogenase (LDH) (AM: hazard ratio [HR], 0.22; 95% confidence interval [CI], 0.06–0.87; p = 0.03, MM: HR, 0.20; 95% CI, 0.08–0.53; p = 0.001) was significantly associated with shorter OS for both subtypes.

Conclusions

The ORR, PFS, and OS with anti‐PD‐1 therapy were poor in patients with AM and MM compared to those previously reported clinical trials for nonacral CM. High serum LDH was associated with significantly shorter OS.

Ultraviolet radiation drives mutations in a subset of mucosal melanomas

Although identified as the key environmental driver of common cutaneous melanoma, the role of ultraviolet radiation (UVR)-induced DNA damage in mucosal melanoma is poorly defined. We analyze 10 mucosal melanomas of conjunctival origin by whole genome sequencing and our data shows a predominance of UVR-associated single base substitution signature 7 (SBS7) in the majority of the samples. Our data shows mucosal melanomas with SBS7 dominance have similar genomic patterns to cutaneous melanomas and therefore this subset should not be excluded from treatments currently used for common cutaneous melanoma.

Immunotherapy for advanced melanoma: current situation in Japan

Treatment with immune checkpoint inhibitors provides long-term survival for patients with advanced melanoma. Improvements in the overall survival of advanced melanoma patients have been achieved with anti-PD-1 monotherapy and anti-PD-1+ CTLA4 combination therapy, but there are still many issues to resolve. Acral, mucosal and uveal melanoma have been less responsive to immune checkpoint inhibitors than cutaneous melanoma. For patients who have achieved a good response, it is still not known how long the anti-PD-1 therapy should be administered. Moreover, there is limited treatment for patients who relapse during or after adjuvant anti-PD-1 therapy. Here, we review the current evidence regarding the clinical effects of immunotherapy for advanced melanoma. Moreover, we review previous studies of acral, mucosal and uveal melanoma, and we discuss the recent findings regarding durable response after the cessation of anti-PD-1 therapy, and treatment options for recurrence after adjuvant therapy.

An update on the safety of nivolumab for the treatment of advanced melanoma

Introduction: Due to its unique mechanism of action as an immune checkpoint inhibitor, nivolumab has high antitumor activity, but at the same time this mechanism is responsible for immune-related adverse events that may limit patients' safety and therapy continuation.Areas covered: Long-term safety of nivolumab including 5-year follow-up, safety of nivolumab treatment after ipilimumab therapy, safety of nivolumab in challenging subgroups (elderly, patients with brain metastases, patients with autoimmune disorders), safety of nivolumab in with rare melanoma subtypes (including mucosal melanoma), as well as specificity of AEs reported for nivolumab treatment in melanoma patients in comparison to other cancer types and other immunotherapy molecules, and impact of AEs on response rates and PFS on nivolumab treatment are discussed.Expert opinion: Search for biomarkers that would help us to identify patient populations that may suffer from severe nivolumab toxicity could help in selecting patients that should not be treated with this type of therapy. Novel combinations and immunotherapy drugs including use of NKTR-214 (IL-2 pathway), lymphocyte-activation gene 3 (LAG-3), local injections of talimogene laherparepvec (T-VEC), or systemic use of T-cell receptors agonists such as OX40, CD137, ICOS-1, could provide regimens with limited toxicity and higher activity.

Immune Checkpoint Inhibitors in Advanced Acral Melanoma: A Systematic Review

Introduction

Acral melanoma (AM) has different biological characteristics from cutaneous melanoma. Although systemic therapeutic strategies for advanced AM resemble those for advanced cutaneous melanoma, the evidence of the clinical use of immune checkpoint inhibitors (ICIs) for AM is still inadequate. We aimed to systematically analyze the therapeutic effects and safety profile of ICI treatments in advanced AM.

Methods

This systematic review was conducted in line with a previously registered protocol. Three electronic databases, conference abstracts, clinical trial registers, and reference lists of included articles were searched for eligible studies. The primary outcomes were therapeutic effects, and the secondary outcomes were the safety profiles.

Results

This systematic review included six studies investigating anti-CTLA-4 immunotherapy, 12 studies investigating anti-PD-1 immunotherapy, one study investigating the combination therapy of anti-CTLA-4 and anti-PD-1, and one study investigating anti-PD-1 immunotherapy in combination with radiotherapy. In most studies investigating ipilimumab, the anti-CTLA-4 antibody, the objective response rate ranged from 11.4 to 25%, the median progression-free survival ranged from 2.1 to 6.7 months, and the median overall survival was more than 7.16 months. For studies discussing anti-PD-1 immunotherapy with nivolumab, pembrolizumab, or JS001, the objective response rate ranged from 14 to 42.9%, the median progression-free survival ranged from 3.2 to 9.2 months, and the median overall survival was more than 14 months. The combination therapy of anti-CTLA-4 and anti-PD-1 immunotherapy showed better efficacy with an objective response rate of 42.9% than single-agent therapy. The retrospective study investigating the combination therapy of anti-PD-1 immunotherapy and radiation showed no overall response. Few outcomes regarding safety were reported in the included studies.

Conclusions

ICIs, especially anti-CTLA-4 monoclonal antibodies combined with anti-PD-1 antibodies, are effective systematic treatments in advanced AM. However, there remains a lack of high-level evidence to verify their efficacy and safety and support their clinical application.

Efficacy and safety of carbon-ion radiotherapy for the malignant melanoma: A systematic review

Malignant melanomas (MMs) were the fifth most common cancer in men and the sixth most common cancer in women in 2018, respectively. These are characterized by high metastatic rates and poor prognoses. We systematically reviewed safety and efficacy of carbon-ion radiotherapy (CIRT) for treating MMs. Eleven studies were eligible for review, and the data showed that MM patients showed better local control with low recurrence and mild toxicities after CIRT. Survival rates were slightly higher in patients with cutaneous or uveal MMs than in those with mucosal MMs. CIRT in combination with chemotherapy produced higher progression-free survival rates than CIRT only. In younger patients, higher rates of distant metastases of gynecological MMs were observed. The data indicated that CIRT is effective and safe for treating MMs; however, a combination with systemic therapy is recommended to ensure the best possible prognosis for MMs.

Efficacy of immune checkpoint inhibitors in different types of melanoma

Immunotherapy can be used for cutaneous, mucosal, uveal and conjunctival melanoma. Nevertheless, we cannot expect the same benefit from checkpoint inhibitors for all the types of melanoma. The different biological features can explain the variable efficacy. The main results obtained with immune checkpoint inhibitors in the various types of melanoma were reviewed.

Anti-PD1 checkpoint inhibitor therapy in acral melanoma: a multicenter study of 193 Japanese patients

BACKGROUND

Acral melanoma (AM) is an epidemiologically and molecularly distinct entity that is underrepresented in clinical trials on immunotherapy in melanoma. We aimed to analyze the efficacy of anti-programmed cell death 1 (anti-PD-1) antibodies in advanced AM.

PATIENTS AND METHODS

We retrospectively evaluated unresectable stage III or stage IV AM patients treated with an anti-PD-1 antibody in any line at 21 Japanese institutions between 2014 and 2018. The clinicobiologic characteristics, objective response rate (ORR, RECIST), survival estimated using Kaplan-Meier analysis, and toxicity (Common Terminology Criteria for Adverse Events 4.0.) were analyzed to estimate the efficacy of the anti-PD-1 antibodies.

RESULTS

In total, 193 patients (nail apparatus, 70; palm and sole, 123) were included in the study. Anti-PD-1 antibody was used as first-line therapy in 143 patients (74.1%). Baseline lactate dehydrogenase (LDH) was within the normal concentration in 102 patients (52.8%). The ORR of all patients was 16.6% (complete response, 3.1%; partial response, 13.5%), and the median overall survival (OS) was 18.1 months. Normal LDH concentrations showed a significantly stronger association with better OS than abnormal concentrations (median OS 24.9 versus 10.7 months; P < 0.001). Although baseline characteristics were similar between the nail apparatus and the palm and sole groups, ORR was significantly lower in the nail apparatus group [6/70 patients (8.6%) versus 26/123 patients (21.1%); P = 0.026]. Moreover, the median OS in this group was significantly poorer (12.8 versus 22.3 months; P = 0.03).

CONCLUSIONS

Anti-PD-1 antibodies have limited efficacy in AM patients. Notably, patients with nail apparatus melanoma had poorer response and survival, making nail apparatus melanoma a strong candidate for further research on the efficacy of novel combination therapies with immune checkpoint inhibitors.