Enhanced Survival Associated with Vitiligo Expression during Maintenance Biotherapy for Metastatic Melanoma

The Risk of Keratinocyte Cancer in Vitiligo and the Potential Mechanisms Involved

Although light skin types are associated with increased skin cancer risk, a lower incidence of both melanoma and nonmelanoma skin cancer (NMSC) has been reported in patients with vitiligo. We performed a systematic review and meta-analysis on the NMSC risk in patients with vitiligo, indicating a reduced relative risk ratio of NMSC in vitiligo. Furthermore, we propose a series of hypotheses on the underlying mechanisms, including both immune-mediated and nonimmune-mediated pathways. This study reveals insights into the relationship between vitiligo and keratinocyte cancer and can also be used to better inform patients with vitiligo.

Mendelian Randomization Analysis reveals Inverse Genetic Risks between Skin Cancers and Vitiligo

Several observational studies have demonstrated a consistent pattern of decreased melanoma risk among patients with vitiligo. More recently, this finding has been supported by a suggested genetic relationship between the two entities, with certain variants significantly associated with an increased risk of melanoma, basal cell carcinoma, and squamous cell carcinoma but a decreased risk of vitiligo. We compared 48 associated variants from a recently published GWAS and identified three variants-located in the TYR, MC1R-DEF8, and RALY-EIF2S2-ASIP-AHCY-ITCH loci- that correlated with an increased risk for melanoma, basal cell carcinoma, and squamous cell carcinoma and a decreased risk for vitiligo. We then used results of skin cancers and vitiligo GWAS to compare the shared genetic properties between these two traits through an unbiased Mendelian randomization analysis. Our results suggest that the inverse genetic relationship between common skin cancers and vitiligo is broader than previously reported owing to the influence of shared genome-wide significant associations.

T cell immunotherapies engage neutrophils to eliminate tumor antigen escape variants

Cancer immunotherapies, including adoptive T cell transfer, can be ineffective because tumors evolve to display antigen-loss-variant clones. Therapies that activate multiple branches of the immune system may eliminate escape variants. Here, we show that melanoma-specific CD4+ T cell therapy in combination with OX40 co-stimulation or CTLA-4 blockade can eradicate melanomas containing antigen escape variants. As expected, early on-target recognition of melanoma antigens by tumor-specific CD4+ T cells was required. Surprisingly, complete tumor eradication was dependent on neutrophils and partly dependent on inducible nitric oxide synthase. In support of these findings, extensive neutrophil activation was observed in mouse tumors and in biopsies of melanoma patients treated with immune checkpoint blockade. Transcriptomic and flow cytometry analyses revealed a distinct anti-tumorigenic neutrophil subset present in treated mice. Our findings uncover an interplay between T cells mediating the initial anti-tumor immune response and neutrophils mediating the destruction of tumor antigen loss variants.

The delicate relation between melanocytes and skin immunity: A game of hide and seek

Melanocytes exhibit a complex and intriguing relationship with the skin immune response, leading to several clinical conditions. In some disorders, inappropriate melanocyte destruction (e.g., vitiligo, halo naevi) is problematic, while in others, immune tolerance should be broken (melanoma). Important parts of the dysregulated pathways have been unraveled in pigment disorders, ranging from upregulated interferon (IFN)-γ signaling to memory T cells, regulatory T cells, and immune checkpoints. Although a network of many factors is involved, targeting key players such as IFN-γ or checkpoint inhibitors (e.g., programmed death-ligand 1 (PD-L1)] can shift the balance and lead to impressive outcomes. In this review, we focus on the immunological mechanisms of the most common inflammatory disorders where the interaction of the immune system with melanocytes plays a crucial role. This can provide new insights into the current state of melanocyte research.

Immune-Related Adverse Events in PD-1 Treated Melanoma and Impact Upon Anti-Tumor Efficacy: A Real World Analysis

Background

Anti-PD-1 immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of melanoma by producing durable long-term responses in a subset of patients. ICI-treated patients develop unique toxicities - immune related adverse events (irAEs) – that arise from unrestrained immune activation. The link between irAE development and clinical outcome in melanoma and other cancers is inconsistent; and little data exists on the occurrence of multiple irAEs. We sought to characterize development of single and multiple irAEs, and association of irAE(s) development with clinical variables and impact upon outcomes in advanced melanoma patients treated with anti-PD-1 ICIs.

Methods

We conducted a retrospective study of 190 patients with metastatic melanoma treated with single-agent anti-PD-1 ICI therapy between June 2014 and August 2020 at a large integrated network cancer center identified through retrospective review of pharmacy records. irAEs were graded based on the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.

Results

190 patients were evaluated of whom 114 patients (60.0%) experienced ≥1 irAE, including 30 (15.8%) with grade 3/4 irAEs. The occurrence of any irAE was strongly associated with the development of investigator-assessed response to anti-PD-1 therapy (p < 0.0001); whether evaluated by current (p=0.0082) or best (p=0.0001) response. In patients with ≥2 irAEs, distinct patterns were observed. Median progression-free survival (PFS) and overall survival (OS) were greater in those with any irAE compared to those without (PFS, 28 months vs. 5 months, p < 0.0001; OS, not reached vs. 9 months, p < 0.0001). Development of ≥2 irAEs had a trend towards improved PFS and OS compared to those who developed a single irAE, although this did not reach statistical significance (p=0.2555, PFS; p=0.0583, OS). Obesity but not age or gender was distinctly associated with irAE development.

Conclusions

In this study, we demonstrated that irAE occurrence was significantly associated with response to anti-PD-1 therapy and improved PFS/OS. Those who developed multiple irAEs had a trend towards improved PFS and OS compared to those who developed only a single irAE. Increased BMI but neither age nor gender were associated with irAE development. Distinct patterns of irAEs observed suggest shared etiopathogenetic mechanisms.

IFN-γ-induced PD-L1 expression on human melanocytes is impaired in vitiligo

Mounting evidence shows that the PD-1/PD-L1 axis is involved in tumor immune evasion. This is demonstrated by anti-PD-1 antibodies that can reverse tumor-associated PD-L1 to functionally suppress anti-tumor T-cell responses. Since type I and II interferons are key regulators of PD-L1 expression in melanoma cells and IFN-γ-producing CD8⁺ T cells and IFN-α-producing dendritic cells are abundant in vitiligo skin, we aimed to study the role of PD-1/PD-L1 signalling in melanocyte destruction in vitiligo. Moreover, impaired PD-1/PD-L1 function is observed in a variety of autoimmune diseases. It is, therefore, hypothesized that manipulating PD-1/PD-L1 signalling might have therapeutic potential in vitiligo. The PD-1⁺ T cells were abundantly present in situ in perilesional vitiligo skin, but expression of PD-L1 was limited and confined exclusively to dermal T cells. More specifically, neither melanocytes nor other epidermal skin cells expressed PD-L1. Exposure to IFN-γ, but also type I interferons, increased PD-L1 expression in primary melanocytes and fibroblasts, derived from healthy donors. Primary human keratinocytes only showed increased PD-L1 expression upon stimulation with IFN-γ. More interestingly, melanocytes derived from non-lesional vitiligo skin showed no PD-L1 upregulation upon IFN-γ exposure, while other skin cells displayed significant PD-L1 expression after exposure. In a vitiligo skin explant model, incubation of non-lesional vitiligo skin with activated (IFN-γ-producing) T cells from vitiligo lesions was previously described to induce melanocyte apoptosis. Although PD-L1 expression was induced in epidermal cells in these explants, this induction was completely absent in melanocytes. The lack of PD-L1 upregulation by melanocytes in the presence of IFN-γ-producing T cells shows that melanocytes lack protection against T-cell attack during vitiligo pathogenesis. Manipulating PD-1/PD-L1 signalling may, therefore, be a therapeutic option for vitiligo patients.

Immune checkpoint inhibitor associated vitiligo and its impact on survival in patients with metastatic melanoma: an Italian Melanoma Intergroup study

Background

Checkpoint inhibitors in melanoma can lead to self-immune side-effects such as vitiligo-like depigmentation (VLD). Beyond the reported association with favorable prognosis, there are limited data regarding VLD patient features and their echo on the therapeutic outcomes.

Methods

To assess the association between VLD and a series of clinical and biological features as well as therapeutic outcomes, we built an observational cohort study by recruiting patients who developed VLD during checkpoint inhibitors.

Results

A total of 148 patients from 15 centers (101 men, median age 66 years, BRAF mutated 23%, M1c 42%, Eastern Cooperative Oncology Group (ECOG) status 0/1 99%, normal lactate dehydrogenase 74%) were enrolled. VLD was induced by ipilimumab, programmed cell death-1 (PD-1) inhibitors, and their combination in 32%, 56%, and 12%, respectively. The median onset was 26 weeks and it was associated with other skin and nonskin toxicities in 27% and 28%, respectively. After 3 years of VLD onset, 52% (95% confidence interval 39% to 63%) were progression free and 82% (95% confidence interval 70% to 89%) were still alive. The overall response rate was 73% with 26% complete response. Univariable analysis indicated that BRAF V600 mutation was associated with a better overall survival (P = 0.028), while in multivariable analysis a longer progression-free survival was associated with BRAF V600 (P = 0.093), female sex (P = 0.008), and M stage other than 1a (P = 0.024). When VLD occurred, there was a significant decrease of white blood cell (WBC) count (P = 0.05) and derived WBC-to-lymphocytes ratio (dWLR; P = 0.003). A lower monocyte count (P = 0.02) and dWLR (P = 0.01) were also reported in responder patients.

Conclusions

Among VLD population, some features might help to identify patients with an effective response to immunotherapy, allowing clinicians to make more appropriate choices in terms of therapeutic options and duration.

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This multicentric retrospective study outlined the melanoma profile of 148 patients with vitiligo-like depigmentation (VLD) induced by checkpoint inhibitors.

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Median VLD onset was 26 weeks and it was associated with other immune toxicities in one-third of cases.

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After 3 years of VLD onset, 52% and 82% of patients, respectively, were progression free and still alive with a response rate of 73%.

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Some features such as BRAF V600, female sex, and M stage were associated with better outcomes as well as a specific blood profile.

Targeting the PD-1/PD-L1 Axis in Human Vitiligo

Autoreactive CD8⁺ T cells play a pivotal role in melanocyte destruction in autoimmune vitiligo. Immunotherapy for melanoma often leads to autoimmune side-effects, among which vitiligo-like depigmentation, indicating that targeting immune checkpoints can break peripheral tolerance against self-antigens in the skin. Therapeutically enhancing immune checkpoint signaling by immune cells or skin cells, making self-reactive T cells anergic, seems a promising therapeutic option for vitiligo. Here, we review the current knowledge on the PD-1/PD-L1 pathway in vitiligo as new therapeutic target for vitiligo therapy.

Vitiligo and Melanoma-Associated Vitiligo: Understanding Their Similarities and Differences

BACKGROUND

There has been a significant increase in the number and efficacy of therapies for advanced melanoma. Immunotherapies, such as anti-cytotoxic T-lymphocyte antigen-4 and programmed cell death-1 inhibitors, have improved the prognosis for patients with advanced melanoma. While spontaneous melanoma-associated vitiligo is a known phenomenon, the occurrence of melanoma-associated vitiligo following melanoma therapy is now recognized to associate with favorable outcomes.

OBJECTIVE

The objective of this article is to provide a comprehensive literature review of melanoma-associated vitiligo and explore the insights these findings provide about the pathobiology of vitiligo and mechanisms underlying melanoma therapies.

METHODS

PubMed and Science Direct databases were searched for studies pertaining to melanoma-associated vitiligo. The 36 studies reviewed included meta-analyses (n = 2), prospective cohort studies (n = 4), prospective observational studies (n = 3), retrospective studies (n = 12), case series (n = 2), and case reports (n = 13).

RESULTS

The basic mechanisms underlying melanoma-associated vitiligo and vitiligo may be shared. Characterization of these mechanisms will identify new biomarkers and therapeutic targets for both melanoma and vitiligo.

CONCLUSIONS

Co-opting the immune system to target tumor antigens highlights the potential overlap between anti-tumor immunity and autoimmunity. The development of vitiligo-like depigmentation in association with immunotherapy for melanoma may provide insights into both the immune response against melanoma as well as the pathogenesis of vitiligo.

Adoptive cell transfer (ACT) of autologous tumor-infiltrating lymphocytes (TILs) to treat malignant melanoma: the dawn of a chimeric antigen receptor T (CAR-T) cell therapy from autologous donor

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) are B, T-helper, and T-cytotoxic lymphocytes migrated from the blood or lymph stream toward a tumor with the aim to infiltrate and destroy it. They can be histologically graded as brisk, nonbrisk, or absent. Malignant melanoma has been the first malignancy found to be correlated with TILs status, being brisk TILs associated with better clinical outcomes. By the terminology of "adoptive cell transfer" (ACT), the medical oncology refers to the transfer of cells in a tumor-bearing patient from the same recipient or a healthy donor.

METHODS

A PubMed literature search on the topic has been performed. Additional documents known to the authors and identified from the reference list of cited publications have been included.

RESULTS

In the past, autologous TILs ACT was successfully tested for the treatment of malignant melanoma and, today, it is a standardized procedure in several centers around the world. It represents the first research step toward the bioengineered chimeric antigen receptor T (CAR-T) cell therapy from autologous donor.

CONCLUSIONS

Both autologous TILs ACT and CAR-T cell therapy from autologous donor exploit the anticancer power of targeted self-lymphocytes, but CAR-T cell technology also virtually allows treatment of those melanomas devoid of TILs or with so few cytotoxic TILs that are difficult to identify.

Vitiligo expansion and extent correlate with durable response in anti-programmed death 1 antibody treatment for advanced melanoma: A multi-institutional retrospective study

Vitiligo is an autoimmune disorder resulting from the destruction of melanocytes. Several reports indicate the association between vitiligo and treatment response in advanced melanoma during immunotherapy. It has not been investigated, however, if an increase of vitiligo while on treatment with anti-programmed death 1 (PD-1) antibodies is associated with more durable responses. The aim of this study is to evaluate the correlation between the vitiligo dynamics and clinical efficacy of anti-PD-1 antibodies. This study included advanced melanoma patients who were treated with nivolumab or pembrolizumab and developed vitiligo thereafter. Correlation between vitiligo expansion (defined as an increase of lesion size at two separate time points at least 4 weeks apart) as well as vitiligo extent (body surface area [BSA] affected) and clinical efficacy based on response rate, progression-free survival and overall survival was assessed. We retrospectively reviewed 29 patients. The median time from the initiation of anti-PD-1 antibody to vitiligo onset was 4.3 months in patients who showed a response and 5.5 months in patients who showed no response (P = 0.31). Twelve patients showed vitiligo expansion, and in nine of these patients, vitiligo increased to grade 2 (covering ≥ 10% BSA). Vitiligo expansion and grade 2 vitiligo showed no improvement in treatment response (P = 0.59 and 0.25) but were associated with prolonged progression-free survival (P = 0.019 and 0.04). Grade 2 vitiligo also showed a trend for prolonged overall survival (P = 0.07). Trend of expansion and larger vitiligo extent may be predictive factors of prolonged survival during anti-PD-1 antibody in melanoma patients.

Correlation between cutaneous adverse events and prognosis in patients with melanoma treated with nivolumab: A single institutional retrospective study

Treatment for patients with unresectable melanoma has been dramatically changed by the use of immunocheckpoint inhibitors (ICI). In this study, we reviewed patients with unresectable stage III/IV melanoma, who were treated with nivolumab between July 2014 and March 2017 at the Department of Dermatologic Oncology, National Cancer Center Hospital, Tokyo, and retrospectively recorded cutaneous adverse events (cAE), development of vitiligo, clinical characteristics and clinical responses. We identified 128 patients, 61 (47.7%) of whom showed cAE, including 30 (23.4%) with development or exacerbation of vitiligo. The prognosis of patients with melanoma treated with ICI correlated with cAE, including development of vitiligo. Patients with cAE showed better objective responses (41.0% vs 6.0%, P < 0.001), progression-free survival (PFS) (377 vs 61 days, P < 0.001) and overall survival (OS) (763 vs 209 days, P < 0.001) than did patients without cAE. Patients who developed vitiligo showed better objective responses (53.3% vs 29.0% vs 6.0%, P < 0.001), PFS (median, not reached vs 317 vs 65 days, P < 0.001) and OS (not reached vs 689 vs 209 days, P < 0.001) than did patients with other cAE and patients without cAE. Landmark analysis showed development of vitiligo starting 20 weeks after starting nivolumab correlated with better OS. In multivariate analysis, OS correlated with performance status, number of metastasized organs, cAE other than vitiligo and development of vitiligo. Despite the fact that the correlation between other cAE and OS was less than that of vitiligo, cAE may be a simple marker of favorable prognosis.

Skin-resident memory T cells as a potential new therapeutic target in vitiligo and melanoma

Tissue-resident memory T (T_RM ) cells are abundant in the memory T cell pool and remain resident in peripheral tissues, such as the skin, where they act as alarm sensors or cytotoxic killers. T_RM cells persist long after the pathogen is eliminated and can respond rapidly upon reinfection with the same antigen. When aberrantly activated, skin-located T_RM cells have a profound role in various skin disorders, including vitiligo and melanoma. Autoreactive T_RM cells are present in human lesional vitiligo skin and mouse models of vitiligo, which suggests that targeting these cells could be effective as a durable treatment strategy for vitiligo. Furthermore, emerging evidence indicates that induction of melanoma-reactive T_RM cells is needed to achieve effective protection against tumor growth. This review highlights seminal reports about skin-resident T cells, focusing mainly on their role in the context of vitiligo and melanoma, as well as their potential as therapeutic targets in both diseases.

Survival and prognosis of individuals receiving programmed cell death 1 inhibitor with and without immunologic cutaneous adverse events

BACKGROUND

The treatment response to new immunotherapy in advanced melanoma patients remains varied between individuals. Immune-related cutaneous side effects might have prognostic value.

OBJECTIVE

To determine whether development of ≥1 of the 3 immune-mediated cutaneous events (eczema, lichenoid reaction, or vitiligo-like depigmentation) is associated with improved progression-free survival.

METHODS

A cohort study of adults with stage IIIC-IV melanoma treated with pembrolizumab or nivolumab during May 1, 2012-February 1, 2018, at Westmead Hospital, Sydney, Australia. Treatment response was based on iRECIST version 1.1.

RESULTS

In total, 82 patients of an average age of 59.9 years were included. Median follow-up was 40.7 months; 33 patients had ≥1 target skin reaction. Skin reactions developed in one-third of individuals by 6 months. At any given time, the instantaneous risk of disease progression and death was lower for individuals who had ≥1 cutaneous adverse event (CAE) develop. Compared with individuals with no CAE, the hazard ratio for disease progression and death for individuals who had ≥1 CAE develop was 0.46 (95% confidence interval 0.23-0.91; P = .025) by the time-dependent Cox proportional hazards model.

LIMITATIONS

Single-center study.

CONCLUSION

This study demonstrates an association between the development of ≥1 of 3 CAEs and improved progression-free survival in this cohort of patients.

Markedly Reduced Risk of Internal Malignancies in Patients With Vitiligo: A Nationwide Population-Based Cohort Study

PURPOSE

Recent studies indicated that the autoimmunity of vitiligo exerts effects on cells other than melanocytes, which confer reduced risks of both melanoma and nonmelanoma skin cancers in patients with vitiligo. However, the risk of internal malignancy in patients with vitiligo has not been elucidated.

PATIENTS AND METHODS

We conducted a population-based retrospective cohort study using data from the Korean National Health Insurance claims database obtained from January 2007 to December 2016. All patients age 20 years or older with vitiligo who had at least two contacts with a physician from 2009 to 2016, during which a principal diagnosis was made, were identified (vitiligo group). Controls were randomly selected (two per patient with vitiligo) after frequency matching with the vitiligo group for age and sex during the same period (control group).

RESULTS

A total of 101,078 patients with vitiligo and 202,156 controls without vitiligo were included. The incidence rates of internal malignancies were 612.9 and 708.9 per 100,000 person-years in the vitiligo and control groups, respectively. Patients with vitiligo showed a significantly reduced risk of overall internal malignancies (hazard ratio [HR], 0.86; 95% CI, 0.82 to 0.89; P < .001) compared with controls without vitiligo after adjustments for age, sex, and comorbidities. With regard to organ-specific malignancies, patients with vitiligo showed a remarkably decreased risk of cancer in the colon and rectum (HR, 0.62; 95% CI, 0.55 to 0.69; P < .001), ovary (HR, 0.62; 95% CI, 0.46 to 0.83; P < .001), and lung (HR, 0.75; 95% CI, 0.65 to 0.86; P < .001).

CONCLUSION

Vitiligo was associated with a reduced risk of overall internal malignancies. These findings suggest that autoimmune diseases, including vitiligo, may provide immune surveillance for the development of cancer beyond the targeted organ.

Endocrine Toxicity of Cancer Immunotherapy Targeting Immune Checkpoints

Immune checkpoints are small molecules expressed by immune cells that play critical roles in maintaining immune homeostasis. Targeting the immune checkpoints cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death 1 (PD-1) with inhibitory antibodies has demonstrated effective and durable antitumor activity in subgroups of patients with cancer. The US Food and Drug Administration has approved several immune checkpoint inhibitors (ICPis) for the treatment of a broad spectrum of malignancies. Endocrinopathies have emerged as one of the most common immune-related adverse events (irAEs) of ICPi therapy. Hypophysitis, thyroid dysfunction, insulin-deficient diabetes mellitus, and primary adrenal insufficiency have been reported as irAEs due to ICPi therapy. Hypophysitis is particularly associated with anti-CTLA-4 therapy, whereas thyroid dysfunction is particularly associated with anti-PD-1 therapy. Diabetes mellitus and primary adrenal insufficiency are rare endocrine toxicities associated with ICPi therapy but can be life-threatening if not promptly recognized and treated. Notably, combination anti-CTLA-4 and anti-PD-1 therapy is associated with the highest incidence of ICPi-related endocrinopathies. The precise mechanisms underlying these endocrine irAEs remain to be elucidated. Most ICPi-related endocrinopathies occur within 12 weeks after the initiation of ICPi therapy, but several have been reported to develop several months to years after ICPi initiation. Some ICPi-related endocrinopathies may resolve spontaneously, but others, such as central adrenal insufficiency and primary hypothyroidism, appear to be persistent in most cases. The mainstay of management of ICPi-related endocrinopathies is hormone replacement and symptom control. Further studies are needed to determine (i) whether high-dose corticosteroids in the treatment of ICPi-related endocrinopathies preserves endocrine function (especially in hypophysitis), and (ii) whether the development of ICPi-related endocrinopathies correlates with tumor response to ICPi therapy.

Vitiligo-like lesions occurring in patients receiving anti-programmed cell death-1 therapies

Antibody-based therapeutics targeting programmed cell death 1 (PD-1) have shown strong efficacy in the treatment of metastatic cancers as melanoma. However, restoring the immune function with these therapies to target cancer cells leads to immune side effects including immune cutaneous events. Vitiligo-like lesions in patients receiving anti-PD-1 is one of the most common skin adverse event reported and the incidence seems to be higher than in patients receiving other immune-checkpoints therapies. Initially described in patients with metastatic melanoma, vitiligo-like lesions have now been reported in other metastatic cancers treated with anti-PD-1. Several reports suggest that this side effect could be different from spontaneously occurring vitiligo and could be associated with increased response to the therapy and patients' survival. The aim of this review is to provide an overview of the clinical presentation of vitiligo-like lesions occurring in patients receiving anti-PD-1, and the hypothesis to explain the mechanism involved in the development of these lesions.

Cytokines, Chemokines, and Other Biomarkers of Response for Checkpoint Inhibitor Therapy in Skin Cancer

Immunotherapy for skin malignancies has ushered in a new era for cancer treatments by demonstrating unprecedented durable responses in the setting of metastatic Melanoma. Consequently, checkpoint inhibitors are now the first-line treatment of metastatic melanoma and widely used as adjuvant therapy for stage III disease. With the observation that higher tumor mutational burden correlates with a better response, checkpoint inhibitors are tested in other skin cancer types of known high tumor mutational burden with promising results and recently became the first-ever FDA-approved treatment for metastatic Merkel cell carcinoma. The emerging new standards-of-care will necessitate more precise biomarkers and predictors for treatment response and immune-related adverse events. Measurable immune-related mediators are currently under investigation as factors that promote or block the response to cancer immunotherapy and may provide insights into the underlying immune response to the tumor. Cytokines and chemokines are such mediators and are crucial for facilitating the recruitment and activation of specific subsets of leukocytes within the microenvironment of skin cancers. The exact mechanisms of how these meditators, both immunological and non-immunological, operate in the tumor microenvironment is an area of active research, so to reliable biomarkers of responses to cancer immunotherapy. Here, we will review and summarize the expanding body of literature for immune-related biomarkers pertaining to Melanoma, Basal cell carcinoma, Squamous cell carcinoma, and Merkel cell carcinoma, highlighting clinically relevant checkpoint inhibitor therapy biomarker advancements.

Immune-related adverse events correlate with improved survival in patients undergoing anti-PD1 immunotherapy for metastatic melanoma

BACKGROUND

Therapeutic chances for metastatic melanoma have consistently changed over the last years with the advent of antibodies targeting the programmed cell death protein-1 (PD-1). Onset of immune-related adverse events (irAEs) during treatment can be a source of concern, and the association with survival outcome is yet to be defined.

PATIENTS AND METHODS

Data of consecutive patients treated with anti-PD1 (nivolumab or pembrolizumab) for metastatic melanoma between July 2013 and January 2018 were retrospectively reviewed. Baseline factors, together with onset of irAEs and vitiligo during treatment, were evaluated to identify predictors of progression-free (PFS) and overall (OS) survival. PFS and OS were assessed using Kaplan-Meier and Cox models.

RESULTS

Overall, 173 patients were included in the present analysis, and 102 patients (59%) experienced irAEs. Disease control rate was 51%. Median (interquartile range) PFS and OS were 4.9 (2.6-13.3) and 8.6 (3.5-18.3) months, respectively. At multivariate analysis, irAEs occurrence was independently associated with improved PFS [HR 0.47 (95% CI 0.26, 0.86); p = 0.016], and correlated with better OS [HR 0.39 (95% CI 0.18, 0.81); p = 0.007]. Among various irAEs, the occurrence of vitiligo was associated with a trend toward a non-significant improved OS in comparison with other irAEs (p = 0.061). Median OS was undefined for patients experiencing vitiligo vs. 21.9 months for patients with other irAEs vs. 9.7 months for patients who had no irAEs (p = 0.003).

CONCLUSIONS

Our study underlines the association between irAEs and survival outcomes from anti-PD1 therapy. Careful management of treatment-related toxicity can lead to achieve maximum clinical benefit from this therapy.

Vitiligo-like lesions in a patient treated with nivolumab for renal cell carcinoma

RATIONALE

The introduction of immune check-point inhibitors (ICIs) in the treatment of solid neoplasms is associated with the need to know and manage a new type of side effects that are commonly defined immune-mediated adverse events. Dermatologic immune-mediated adverse events are relatively common. Vitiligo-like lesions, defined as hypopigmented skin lesions, have already been associated with the use of ICIs in particular in patients with malignant melanoma, probably due to a common autoimmune mechanism against both melanoma cells and normal melanocytes. The onset of vitiligo-like lesions is very rare in non-melanoma patients and nowadays only few cases are described in the literature.

PATIENT CONCERNS

We described the case of a heavily pre-treated woman affected by renal cell carcinoma that has been treated with nivolumab for 2 years obtaining a stabilization of disease after an initial mild progression. After 9 months from the beginning of nivolumab, when the disease has reached its maximum stabilization, the patient developed vitiligo-like lesions of the back win halo nevi.

DIAGNOSES

Vitiligo like lesion of the back not pre-existing before nivolumab treatment. The etiology was assumed to be nivolumab related as a result of an autoimmune activation against normal melanocytes.

INTERVENTIONS

The patient was followed with dermatological evaluations without changes in nivolumab dose and schedule OUTCOMES:: No variations of the described lesions were recorded after the first description. The patients underwent a durable stabilization of her tumor.

LESSONS

This case on the one hand is the first case of vitiligo-like lesions associated with ICIs in patients affected by renal cell carcinoma, and on the other hand it seems to confirm that the onset of immumomediate adverse reactions, but in particular vitiligo lesions, can probably be considered a sign of response to immunological treatments probably as a consequence of activation of the immune response.

NOD mice, susceptible to pancreatic autoimmunity, demonstrate delayed growth of pancreatic cancer

Pancreatic cancer is a high mortality form of cancer, with a median survival only six months. There are multiple associated risk factors associated, most importantly type 2 diabetes, obesity, pancreatitis and smoking. The relative rarity of the disease, however, has made it difficult to dissect causative risk factors, especially with related risk factors. A major unanswered question with important therapeutic implications is the effect of immunological responses on pancreatic cancer formation, with data from other cancers suggesting the potential for local immunological responses to either increase cancer development or increase cancer elimination. Due to the rarity and late diagnosis of pancreatic cancer direct epidemiological evidence is lacking, thus necessitating a reliance on animal models. Here we investigated the relationship between pancreatic autoimmunity and cancer by backcrossing the well characterised Ela1-Tag transgenic model of pancreatic cancer onto the pancreatic autoimmune susceptible NOD mouse strain. Through longitudinal magnetic resonance imaging we found that the NOD genetic background delayed the onset of pancreatic tumours and substantially slowed the growth rate of tumours after development. These results suggest that elevated autoimmune surveillance of the pancreas limits tumour formation and growth, identifying pancreatic cancer as a promising target for immune checkpoint blockade therapies that unleash latent autoimmunity.

Immune and molecular correlates in melanoma treated with immune checkpoint blockade

Immunotherapy for metastatic melanoma has a decades-long history, and the relatively recent use of checkpoint inhibitors has revolutionized treatment. Durable and sometimes complete remission of metastatic melanoma is now achievable in some patients who receive checkpoint-blocking therapy. However, it is unclear why some patients fare better than others. This review highlights several molecular indicators of response to checkpoint inhibition in metastatic melanoma, focusing on tumor programmed death ligand 1 expression, major histocompatibility complex class I expression, mutational load in the tumor, and T-cell infiltration into the tumor. In addition, clinical correlates of response, notably vitiligo and other immune-related adverse events, can potentially shed light on the mechanisms by which checkpoint blockade may achieve such great success, particularly in melanoma. The authors propose that microphthalmia-associated transcription factor-a key regulator of melanocyte survival, melanin production, and melanoma transformation-produces a molecular landscape in melanocytes and melanoma cells that can make melanomas particularly susceptible to checkpoint blockade and also can result in immune attack on normal melanocytes. Cancer 2017;123:2143-53. © 2017 American Cancer Society.

A novel in silico framework to improve MHC-I epitopes and break the tolerance to melanoma

Tolerance toward tumor antigens, which are shared by normal tissues, have often limited the efficacy of cancer vaccines. However, wild type epitopes can be tweaked to activate cross-reactive T-cell clones, resulting in antitumor activity. The design of these analogs (i.e., heteroclitic peptides) can be difficult and time-consuming since no automated in silico tools are available. Hereby we describe the development of an in silico framework to improve the selection of heteroclitic peptides. The Epitope Discovery and Improvement System (EDIS) was first validated by studying the model antigen SIINFEKL. Based on artificial neural network (ANN) predictions, we selected two mutant analogs that are characterized by an increased MHC-I binding affinity (SIINFAKL) or increased TCR stimulation (SIIWFEKL). Therapeutic vaccination using optimized peptides resulted in enhanced antitumor activity and against B16.OVA melanomas in vivo. The translational potential of the EDIS platform was further demonstrated by studying the melanoma-associated antigen tyrosinase related protein 2 (TRP2). Following therapeutic immunization with the EDIS-derived epitope SVYDFFAWL, a significant reduction in the growth of established B16.F10 tumors was observed, suggesting a break in the tolerance toward the wild type epitope. Finally, we tested a multi vaccine approach, demonstrating that combination of wild type and mutant epitopes targeting both TRP2 and OVA antigens increases the antitumor response. In conclusion, by taking advantage of available prediction servers and molecular dynamics simulations, we generated an innovative platform for studying the initial sequences and selecting lead candidates with improved immunological features. Taken together, EDIS is the first automated algorithm-driven platform to speed up the design of heteroclitic peptides that can be publicly queried online.

Vitiligo in a patient with lung adenocarcinoma treated with nivolumab: A case report

Nivolumab, an anti-programmed cell death-1 protein monoclonal antibody, is effective for treating patients with late-stage non-small-cell lung cancer. Immune checkpoint inhibitors such as nivolumab induce various kinds of immune-related adverse events, including vitiligo. Vitiligo has been reported in patients with melanoma but not lung cancer. We describe a 75-year-old man with lung adenocarcinoma, stage 4 with pleural and pericardial effusion, that progressed after first-line chemotherapy. Subsequently, he was treated with nivolumab as second-line therapy. After 6days of administering nivolumab, he developed vitiligo suddenly on the trunk of his body. Except for vitiligo, his physical examination was normal, and treatment with nivolumab was well tolerated. Therefore, this treatment was continued without further development or expansion of vitiligo. A computed tomography scan showed a reduction in the size of the lung nodule and stabilization of the pleural and pericardial effusion. This is the first case of vitiligo associated with the use of nivolumab in a patient with lung adenocarcinoma.

CD4+ T cell-mediated cytotoxicity eliminates primary tumor cells in metastatic melanoma through high MHC class II expression and can be enhanced by inhibitory receptor blockade

Metastatic melanoma is a rapidly progressing disease with high mortality rate and limited treatment options. Immunotherapy based on tumor-targeting cytotoxic T cell responses represents a promising strategy. To assist in its development, we examined the possibility and efficacy of using CD4+ cytotoxic T cells. The regulatory mechanisms controlling CD4+ T cell-mediated cytotoxicity were also investigated. We found that naturally occurring granzyme B and perforin-expressing CD4+ cytotoxic T cells can be recovered from metastatic melanoma patients at significantly elevated frequencies compared to those from healthy controls. These CD4+ cytotoxic T cells were also capable of killing autologous tumor cells harvested from metastatic melanoma, independent of CD8+ T cells or any other cell types. However, several restricting factors were observed. First, the cytolytic activity by CD4+ T cells required high MHC class II expression on melanoma cells, which was not satisfied in a subset of melanomas. Second, the granzyme B and perforin release by activated CD4+ cytotoxic T cells was reduced after coculturing with autologous melanoma cells, characterized by low LAMP-1 expression and low granzyme B and perforin secretion in the supernatant. This suggested that inhibitory mechanisms were present to suppress CD4+ cytotoxic T cells. Indeed, blockade of PD-1 and CTLA-4 had increased the cytolytic activity of CD4+ T cells but was only effective in MHC class II high but not MHC class II low melanomas. Together, our study showed that CD4+ T cell-mediated cytotoxicity could eliminate primary melanoma cells but the efficacy depended on MHC class II expression.

Correlation between vitiligo occurrence and clinical benefit in advanced melanoma patients treated with nivolumab: A multi-institutional retrospective study

Vitiligo is occasionally seen in melanoma patients. Although several studies indicate a correlation between vitiligo occurrence and clinical response in melanoma patients receiving immunotherapy, most studies have included heterogeneous patient and treatment settings. The aim of this study is to investigate the correlation between the occurrence of vitiligo and clinical benefit of nivolumab treatment in advanced melanoma patients. We retrospectively reviewed unresectable stage III or IV melanoma patients treated with nivolumab. Of 35 melanoma patients treated with nivolumab, 25.7% (9/35) developed vitiligo during treatment. The time from the start of nivolumab treatment to occurrence of vitiligo ranged 2-9 months (mean, 5.2). Of nine patients who developed vitiligo, two (22.2%) had a complete response to nivolumab and two (22.2%) had a partial response. The objective response rate was significantly higher in patients with vitiligo than in patients without vitiligo (4/9 [44.4%] vs 2/26 [7.7%]; P = 0.027). The mean time to vitiligo occurrence in patients achieving an objective response was significantly less than that in patients who showed no response (3.1 vs 6.8 months, P = 0.004). Vitiligo occurrence was significantly associated with prolonged progression-free and overall survival (hazard ratio, 0.24 and 0.16; 95% confidence interval, 0.11-0.55 and 0.03-0.79; P = 0.005, and 0.047, respectively). At the 20-week landmark analysis, however, vitiligo was not associated with a statistically significant overall survival benefit (P = 0.28). The occurrence of vitiligo during nivolumab treatment may be correlated with favorable clinical outcome.

Systematic review of the use of granulocyte-macrophage colony-stimulating factor in patients with advanced melanoma

Several immunomodulatory checkpoint inhibitors have been approved for the treatment of patients with advanced melanoma, including ipilimumab, nivolumab and pembrolizumab. Talimogene laherparepvec is the first oncolytic virus to gain regulatory approval in the USA; it is also approved in Europe. Talimogene laherparepvec expresses granulocyte–macrophage colony-stimulating factor (GM-CSF), and with other GM-CSF-expressing oncolytic viruses in development, understanding the clinical relevance of this cytokine in treating advanced melanoma is important. Results of trials of GM-CSF in melanoma have been mixed, and while GM-CSF has the potential to promote anti-tumor responses, some preclinical data suggest that GM-CSF may sometimes promote tumor growth. GM-CSF has not been approved as a melanoma treatment. We undertook a systematic literature review of studies of GM-CSF in patients with advanced melanoma (stage IIIB–IV). Of the 503 articles identified, 26 studies met the eligibility criteria. Most studies investigated the use of GM-CSF in combination with another treatment, such as peptide vaccines or chemotherapy, or as an adjuvant to surgery. Some clinical benefit was reported in patients who received GM-CSF as an adjuvant to surgery, or in combination with other treatments. In general, outcomes for patients receiving peptide vaccines were not improved with the addition of GM-CSF. GM-CSF may be a valuable therapeutic adjuvant; however, further studies are needed, particularly head-to-head comparisons, to confirm the optimal dosing regimen and clinical effectiveness in patients with advanced melanoma.

Elevated Levels of SOX10 in Serum from Vitiligo and Melanoma Patients, Analyzed by Proximity Ligation Assay

Background

The diagnosis of malignant melanoma currently relies on clinical inspection of the skin surface and on the histopathological status of the excised tumor. The serum marker S100B is used for prognostic estimates at later stages of the disease, but analyses are marred by false positives and inadequate sensitivity in predicting relapsing disorder.

Objectives

To investigate SOX10 as a potential biomarker for melanoma and vitiligo.

Methods

In this study we have applied proximity ligation assay (PLA) to detect the transcription factor SOX10 as a possible serum marker for melanoma. We studied a cohort of 110 melanoma patients. We further investigated a second cohort of 85 patients with vitiligo, which is a disease that also affects melanocytes.

Results

The specificity of the SOX10 assay in serum was high, with only 1% of healthy blood donors being positive. In contrast, elevated serum SOX10 was found with high frequency among vitiligo and melanoma patients. In patients with metastases, lack of SOX10 detection was associated with treatment benefit. In two responding patients, a change from SOX10 positivity to undetectable levels was seen before the response was evident clinically.

Conclusions

We show for the first time that SOX10 represents a promising new serum melanoma marker for detection of early stage disease, complementing the established S100B marker. Our findings imply that SOX10 can be used to monitor responses to treatment and to assess if the treatment is of benefit at stages earlier than what is possible radiologically.

Cutaneous manifestations associated with melanoma

Melanoma is a malignancy most commonly arising from the skin; therefore, primary melanoma characteristics are usually the first cutaneous manifestations of melanoma. Cutaneous metastases, which can occur locally or diffusely, are important to detect in a timely manner as treatments for advanced melanoma that impact survival are now available. Melanoma can be associated with local or diffuse pigmentation changes, including depigmentation associated with the leukodermas and hyperpigmentation associated with diffuse melanosis cutis. The leukodermas occur frequently, illustrate the immunogenic nature of melanoma, and may impact prognosis. Paraneoplastic syndromes in association with melanoma are rare, though can occur.

Nivolumab in Resected and Unresectable Metastatic Melanoma: Characteristics of Immune-Related Adverse Events and Association with Outcomes

PURPOSE

Retrospective analysis of irAEs in melanoma patients treated with nivolumab.

EXPERIMENTAL DESIGN

Data were pooled from 148 patients (33 resected, 115 unresectable) treated with nivolumab plus peptide vaccine or nivolumab alone every 2 weeks for 12 weeks. Patients with stable disease or regression received an additional 12-week cycle, then nivolumab alone every 12 weeks for up to 2 additional years. Frequency, grade, and characteristics of immune-related adverse events (irAE) were analyzed. A 12-week landmark survival analysis using a multivariate time-dependent Cox proportional hazard model assessed difference in overall survival (OS) in the presence or absence of irAEs.

RESULTS

IrAEs of any grade were observed in 68.2% of patients (101 of 148). Grade III/IV irAEs were infrequent: 3 (2%) had grade III rash, 2 (1.35%) had asymptomatic grade III elevation in amylase/lipase, and 2 (1.35%) had grade III colitis. A statistically significant OS difference was noted among patients with any grade of irAE versus those without (P ≤ 0.001), and OS benefit was noted in patients who reported three or more irAE events (P ≤ 0.001). Subset analyses showed statistically significant OS differences with rash [P = 0.001; HR, 0.423; 95% confidence interval (CI), 0.243-0.735] and vitiligo (P = 0.012; HR, 0.184; 95% CI, 0.036-0.94). Rash and vitiligo also correlated with statistically significant OS differences in patients with metastatic disease (P = 0.004 and P = 0.028, respectively). No significant survival differences were seen with other irAEs (endocrinopathies, colitis, or pneumonitis).

CONCLUSIONS

Cutaneous irAEs are associated with improved survival in melanoma patients treated with nivolumab, and clinical benefit should be validated in larger prospective analyses.

The prognostic role of the preoperative absolute lymphocyte count and absolute monocyte count in patients with resected advanced melanoma

OBJECTIVES

Published data have reported that components of the peripheral blood are significant prognostic factors in hematologic and solid malignancies. Thus, we sought to investigate if the preoperative absolute lymphocyte count (ALC) and absolute monocyte count (AMC) affects disease progression and survival after complete surgical resection of advanced malignant melanoma.

METHODS

We retrospectively reviewed records of 227 patients with resected advanced malignant melanoma (153 stage III and 74 stage IV) that were treated at the Mayo Clinic from 2000 to 2010. Survival analysis was performed using the Kaplan-Meier method, log-rank tests, and the Cox proportional hazards model for the univariate and multivariate analysis.

RESULTS

Surgically resected stage III melanoma patients with a preoperative AMC<0.6×10/L experienced a longer overall survival (OS) versus AMC≥0.6×10/L (median: 63.9 vs. 34.8 mo, respectively, P<0.008). Multivariate analysis showed AMC to be an independent predictor for OS in stage III patients. Stage IV resected melanoma patients with an ALC≥1.9×10/L experienced a superior median relapse-free survival (RFS) compared with patients with an ALC<1.9×10/L (median: 11.4 vs. 5.4 mo, respectively, P<0.006). Multivariate analysis showed ALC to be an independent predictor for RFS in stage IV patients.

CONCLUSIONS

These data showed that in surgically resected stage III melanoma, preoperative AMC is an independent prognostic factor for OS. In contrast, a higher preoperative ALC is an independent prognostic for longer RFS in surgically resected stage IV melanoma.

Lentivirus-induced 'Smart' dendritic cells: Pharmacodynamics and GMP-compliant production for immunotherapy against TRP2-positive melanoma

Monocyte-derived conventional dendritic cells (ConvDCs) loaded with melanoma antigens showed modest responses in clinical trials. Efficacy studies were hampered by difficulties in ConvDC manufacturing and low potency. Overcoming these issues, we demonstrated higher potency of lentiviral vector (LV)-programmed DCs. Monocytes were directly induced to self-differentiate into DCs (SmartDC-TRP2) upon transduction with a tricistronic LV encoding for cytokines (granulocyte macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4)) and a melanoma antigen (tyrosinase-related protein 2 (TRP2)). Here, SmartDC-TRP2 generated with monocytes from five advanced melanoma patients were tested in autologous DC:T cell stimulation assays, validating the activation of functional TRP2-specific cytotoxic T lymphocytes (CTLs) for all patients. We described methods compliant to good manufacturing practices (GMP) to produce LV and SmartDC-TRP2. Feasibility of monocyte transduction in a bag system and cryopreservation following a 24-h standard operating procedure were achieved. After thawing, 50% of the initial monocyte input was recovered and SmartDC-TRP2 self-differentiated in vitro, showing uniform expression of DC markers, detectable LV copies and a polyclonal LV integration pattern not biased to oncogenic loci. GMP-grade SmartDC-TRP2 expanded TRP2-specific autologous CTLs in vitro. These results demonstrated a simpler GMP-compliant method of manufacturing an effective individualized DC vaccine. Such DC vaccine, when in combination with checkpoint inhibition therapies, might provide higher specificity against melanoma.

Association of Vitiligo and Response in Patients with Metastatic Malignant Melanoma on Temozolomide

Vitiligo-like lesions, although rare, are believed to be a prognostic factor in malignant melanoma. While a predictive role for such lesions was shown with immunomodulatory therapies, this relation was not demonstrated with temozolomide. We present 3 patients with metastatic malignant melanoma who developed vitiligo-like skin lesions accompanying good response to treatment and prolonged survival. Onset of vitiligo-like lesions with temozolomide in metastatic malignant melanoma may predict long-term response for this treatment.

Amelanotic Acral Melanoma Associated with KIT Mutation and Vitiligo

Amelanotic acral melanoma is rare and difficult to diagnose, both clinically and pathologically. KIT mutations are frequently found in acral melanomas and are considered a risk factor for poor prognosis. The presence of vitiligo in melanoma has been reported, and KIT is thought to be partly responsible for the dysfunction and loss of melanocytes observed in vitiligo. We report a case of amelanotic subungual melanoma with multiple metastases that was associated with KIT mutation and vitiligo. An 85-year-old man presented with a 3-year history of a tender erythematous ulcerated tumor on the left third fingertip and developed hypopigmented patches on the face and trunk. Histopathological examination of the ulcerative tumor showed aggregates of tumor cells that were pleomorphic epithelioid cells. Immunohistochemical staining of the tumor cells was positive for S100, HMB45, and c-Kit. Histopathological findings from the hypopigmented patch on the face were consistent with vitiligo. Mutation analysis showed a KIT mutation in exon 17 (Y823D). The patient had metastasis to the brain, liver, bone, and both lungs. The patient refused chemotherapy, and died 3 months after the first visit.

Vitiligo-like depigmentation in patients with stage III-IV melanoma receiving immunotherapy and its association with survival: a systematic review and meta-analysis

PURPOSE

Vitiligo-like depigmentation in patients with melanoma may be associated with more favorable clinical outcome. We conducted a systematic review of patients with stage III to IV melanoma treated with immunotherapy to determine the cumulative incidence of vitiligo-like depigmentation and the prognostic value of vitiligo development on survival.

METHODS

We systemically searched and selected all studies on melanoma immunotherapy that reported on autoimmune toxicity and/or vitiligo between 1995 and 2013. Methodologic quality of each study was appraised using adapted criteria for systematic reviews in prognostic studies. Random-effect models were used to calculate summary estimates of the cumulative incidence of vitiligo-like depigmentation across studies. The prognostic value of vitiligo-like depigmentation on survival outcome was assessed using random-effects Cox regression survival analyses.

RESULTS

One hundred thirty-seven studies were identified comprising 139 treatment arms (11 general immune stimulation, 84 vaccine, 28 antibody-based, and 16 adoptive transfer) including a total of 5,737 patients. The overall cumulative incidence of vitiligo was 3.4% (95% CI, 2.5% to 4.5%). In 27 studies reporting individual patient data, vitiligo development was significantly associated with both progression-free-survival (hazard ratio [HR], 0.51; 95% CI, 0.32 to 0.82; P < .005) and overall survival (HR, 0.25; 95% CI, 0.10 to 0.61; P < .003), indicating that these patients have two to four times less risk of disease progression and death, respectively, compared with patients without vitiligo development.

CONCLUSION

Although vitiligo occurs only in a low percentage of patients with melanoma treated with immunotherapy, our findings suggest clear survival benefit in these patients. Awareness of vitiligo induction in patients with melanoma is important as an indicator of robust antimelanoma immunity and associated improved survival.

Metastatic melanomas of unknown primary show better prognosis than those of known primary: a systematic review and meta-analysis of observational studies

BACKGROUND

Melanoma of unknown primary (MUP) is a condition of metastatic melanoma without a primary lesion.

OBJECTIVE

We sought to identify the prognosis of MUP compared with melanoma of known primary (MKP).

METHODS

We searched for observational studies containing at least 10 patients with MUP from MEDLINE and EMBASE from inception to December 22, 2012. The outcomes of interest were overall and disease-free survival; meta-analyses of hazard ratio stratified by stage using a random effects model were performed. In addition, second systematic review identified risk factors influencing the survival of patients with MUP.

RESULTS

Eighteen studies including 2084 patients with MUP and 5894 with MKP were included. MUP had a better overall survival compared with MKP in stage III (15 studies; hazard ratio 0.83, 95% confidence interval 0.73-0.96, P = .010) and stage IV (6 studies; hazard ratio 0.85, 95% confidence interval 0.75-0.96, P = .008). Secondly, 22 studies including 3312 patients with MUP were reviewed, and increased stage and old age were the risk factors in patients with MUP.

LIMITATIONS

Diverse observational studies were reviewed, and selection and reporting biases are possible.

CONCLUSIONS

The current meta-analyses suggest better survival outcomes in patients with MUP than those in patients with MKP with the same corresponding tumor stage.

Melanoma-associated leukoderma - immunology in black and white?

Melanoma is an 'immunogenic tumor', often highly infiltrated with lymphocytes, which are capable of inducing regression of the primary tumor. The commonly observed phenomenon of regression suggests substantial cross-talk between immune cells and transformed melanocytes. An immune response to melanocyte differentiation antigens common to transformed and normal melanocytes manifests clinically at distant sites as melanoma-associated vitiligo or halo nevi. Despite similar antigenic targets, the pathogenesis and prognosis differ between the different melanoma-associated leukodermas. Understanding immunologic cross-talk between melanocytes and the immune system will aid the development of approaches to combat melanoma.

Radiation-induced melanoma-associated leucoderma, systemic antimelanoma immunity and disease-free survival in a patient with advanced-stage melanoma: a case report and immunological analysis

BACKGROUND

Melanoma is an immunogenic tumour. The development of skin depigmentation or melanoma-associated leucoderma (MAL) has been associated with favourable clinical outcome in patients with metastatic melanoma, especially after immunotherapy. Evidence for clinically meaningful enhancement of melanoma-directed autoimmunity, as indicated by MAL, after radiotherapy without immunotherapy has not yet been published.

OBJECTIVES

We investigated whether a patient with stage IV melanoma, who developed leucoderma in the irradiated skin areas following radiotherapy and experienced exceptional disease-free survival of 3 years despite brain metastasis, possessed antimelanoma immunity that could be linked to the favourable disease course.

METHODS

A detailed immunological analysis was performed consisting of immunohistochemistry of several melanoma tissues, and analyses of T cells isolated from the blood and MAL skin tissue for melanocyte/melanoma specificity and functionality, as well as the presence of a melanoma-specific antibody response.

RESULTS

Immunological analyses showed the presence of CD8+ T cells and antibody responses directed against melanocyte differentiation antigens expressed in the primary tumour, lymph node and brain metastasis, indicating adequate tumour recognition by activated T cells.

CONCLUSION

The immune responses found in this patient, probably enhanced by radiotherapy, are thought to have contributed to his favourable clinical course. Radiotherapy may act as local immunotherapy in patients with melanoma by destroying melanocytes, leading to the induction, or enhancement, of already existent antimelanoma immunity. As in patients treated with immunotherapy, this may lead to MAL, also at distant sites from the treated area. This patient is a clear example of the positive prognostic value of MAL, which is possibly induced by radiotherapy, for patients with melanoma.

Melanoma as a model tumour for immuno-oncology

Melanoma is one of the most aggressive forms of skin cancer. Furthermore, incidence rates are increasing. Until recently, no agent had been shown to improve survival over supportive care and treatment guidelines recommended that patients with metastatic disease were entered into clinical trials. With so few treatment options available, there was a clear need for new, more effective treatments in this setting. Melanoma serves as a 'model' tumour for understanding immunity to cancer. Melanoma tumour-associated antigens were among the first cancer antigens to be identified and classified, with further studies showing that many of these are also expressed by other tumour types. In addition, melanoma regression has been associated with vitiligo, visibly confirming an active role of the immune system in this type of cancer, and spontaneous regression of primary melanomas has also been observed in some cases. These observations, relating to the activity of the immune system in melanoma, provided strong evidence that this tumour would be amenable to immunotherapy, with immunotherapies such as cytokines, adoptive cell transfer and T-cell modulators shown to be an effective therapeutic approach. Against this background, melanoma has long been at the cutting edge of immuno-oncology research and will likely continue to be used as a model tumour to increase our understanding of immuno-oncology and to inform development in other types of cancer.

Identity, potency, in vivo viability, and scaling up production of lentiviral vector-induced dendritic cells for melanoma immunotherapy

SmartDCs (Self-differentiated Myeloid-derived Antigen-presenting-cells Reactive against Tumors) consist of highly viable dendritic cells (DCs) induced to differentiate with lentiviral vectors (LVs) after an overnight ex vivo transduction. Tricistronic vectors co-expressing cytokines (granulocyte-macrophage-colony stimulating factor [GM-CSF], interleukin [IL]-4) and a melanoma antigen (tyrosine related protein 2 [TRP2]) were used to transduce mouse bone marrow cells or human monocytes. Sixteen hours after transduction, the cells were dispensed in aliquots and cryopreserved for identity, potency, and safety analyses. Thawed SmartDCs readily differentiated into highly viable cells with a DC immunophenotype. Prime/boost subcutaneous administration of 1×10(6) thawed murine SmartDCs into C57BL/6 mice resulted into TRP2-specific CD8(+) T-cell responses and protection against lethal melanoma challenge. Human SmartDC-TRP2 generated with monocytes obtained from melanoma patients secreted endogenous cytokines associated with DC activation and stimulated TRP2-specific autologous T-cell expansion in vitro. Thawed human SmartDCs injected subcutaneously in NOD.Rag1(-/-).IL2rγ(-/-) mice maintained DC characteristics and viability for 1 month in vivo and did not cause any signs of pathology. For development of good manufacturing practices, CD14(+) monocytes selected by magnetic-activated cell separation were transduced in a closed bag system (multiplicity of infection of 5), washed, and cryopreserved. Fifty percent of the monocytes used for transduction were recovered for cryopreservation. Thawed SmartDCs produced in two independent runs expressed the endogenous cytokines GM-CSF and IL-4, and the resulting homogeneous SmartDCs that self-differentiated in vitro contained approximately 1.5-3.0 copies of integrated LVs per cell. Thus, this method facilitates logistics, standardization, and high recovery for the generation of viable genetically reprogrammed DCs for clinical applications.

Immunological basis of melanoma-associated vitiligo-like depigmentation

Vitiligo is a skin condition characterized by white, hypopigmented macules. Melanocyte loss is a feature of the disease, and it has been hypothesized that an autoimmune mechanism could be responsible for the depigmentation. Melanoma is a malignancy that develops in melanocytes; if not detected and treated early, it is often deadly. Leukoderma, a condition characterized by depigmentation of the skin, is sometimes associated with malignant melanoma. An immune response against melanocyte antigens leading to destruction of either melanoma cells or melanocytes has been observed in both vitiligo and melanoma. Studies in animal models and humans have shown that humoral and cell-mediated immune responses are involved in modulating cytotoxic activity against tumor cells and normal melanocytes. The study of factors associated with anti-tumor immunopathogenic mechanisms -autoimmunity for example- may provide us with tools for the diagnosis and treatment of diseases such as vitiligo and malignant melanoma.

Sequential local injection of low-dose interferon-beta for maintenance therapy in stage II and III melanoma: a single-institution matched case-control study

OBJECTIVE

To determine the beneficial effect of maintenance therapy in stage II and III melanoma by sequential local injection of low-dose interferon-β.

METHODS

We reviewed 46 patients with stage II and III primary melanoma at our institution from 2004 through 2009. Twenty-one patients were treated with interferon-β maintenance therapy consisting of subcutaneous injection of natural interferon-β at a dose of 3 × 10(6) IU/day for 10 consecutive days, and 25 patients underwent observation alone.

RESULTS

Compared with all patients, overall survival and relapse-free survival were significantly worse in the observation group than in the interferon-β group (p = 0.024 and 0.029, respectively). In stage II, a significant difference in overall survival, but not in relapse-free survival, was seen between the two groups (p = 0.041). When the interferon-β group was stratified by subgroup, there was a statistical difference only between dosage and duration (p = 0.027 and p < 0.001, respectively).

CONCLUSIONS

This study demonstrates that maintenance therapy by interferon-β is beneficial in the outcome of the disease without substantial toxic effects, especially in patients with stage II melanoma. Extension of the duration of treatment beyond 2 years could further improve the therapeutic efficacy of interferon-β.

Cancer and systemic sclerosis: novel insights into pathogenesis and clinical implications

PURPOSE OF REVIEW

Most epidemiologic studies have demonstrated an increased risk of cancer in scleroderma patients. Reasons for this risk increase have been poorly understood and often attributed to cytotoxic therapies or damage from scleroderma. Recognition that some patients have a close temporal relationship between cancer diagnosis and scleroderma clinical onset has focused attention on the possibility that scleroderma may be a paraneoplastic syndrome in a subset of patients. This review will discuss the latest epidemiologic data linking cancer and scleroderma and explore a model for the development of paraneoplastic scleroderma.

RECENT FINDINGS

New investigations have demonstrated an association between RNA polymerase III autoantibodies and a close temporal relationship between cancer diagnosis and the development of clinical scleroderma. A unique nucleolar RNA polymerase III expression pattern has been identified in malignant tissue from these scleroderma patients suggesting that autoantigen expression in the cancer and the autoantibody response are associated. Similar data in inflammatory myositis have illustrated that disease-specific autoantigens may be expressed in cancers and damaged target tissues (muscle) undergoing regeneration.

SUMMARY

These data suggest a model of paraneoplastic autoimmunity in which cross-reactive immune responses may target autoantigens that are expressed in both cancers and diseased autoimmune target tissues.