Treatment of in-transit melanoma with intra-lesional interleukin-2: a systematic review

Intralesional and Infusional Updates for Metastatic Melanoma

Locoregionally advanced and metastatic melanoma represent a challenging clinical problem, but in the era of immune checkpoint blockade and intralesional and infusional therapies, more options are available for use. Isolated limb infusion (ILI) was first introduced in the 1990s for the management of advanced melanoma, followed by the utilization of isolated extremity perfusion (ILP). Following this, intralesional oncolytic viruses, xanthene dyes, and cytokines were introduced for the management of in-transit metastases as well as unresectable, advanced melanoma. In 2015, the Food and Drug Administration (FDA) approved the first oncolytic intralesional therapy, talimogene laherparepvec (T-VEC), for the treatment of advanced melanoma. Additionally, immune checkpoint inhibition has demonstrated efficacy in the management of advanced melanomas, and this improvement in outcomes has been extrapolated to aid in the management of in-transit metastatic disease. Finally, percutaneous hepatic perfusion (PHP), also approved by the FDA, has been reported to have a significant impact on the treatment of hepatic disease in uveal melanoma. While some of these treatments have less utility due to inferior outcomes as well as higher toxicity profiles, there are selective patient profiles for which these therapies carry a role. This review highlights intralesional and infusional therapies for the management of metastatic melanoma.

Current Controversies in Melanoma Treatment

LEARNING OBJECTIVES

After reading this article and viewing the videos, the participant should be able to: 1. Discuss margins for in situ and invasive disease and describe reconstructive options for wide excision defects, including the keystone flap. 2. Describe a digit-sparing alternative for subungual melanoma. 3. Calculate personalized risk estimates for sentinel node biopsy using predictive nomograms. 4. Describe the indications for lymphadenectomy and describe a technique intended to reduce the risk of lymphedema following lymphadenectomy. 5. Offer options for in-transit melanoma management.

SUMMARY

Melanoma management continues to evolve, and plastic surgeons need to stay at the forefront of advances and controversies. Appropriate margins for in situ and invasive disease require consideration of the trials on which they are based. A workhorse reconstruction option for wide excision defects, particularly in extremities, is the keystone flap. There are alternative surgical approaches to subungual tumors besides amputation. It is now possible to personalize a risk estimate for sentinel node positivity beyond what is available for groups of patients with a given stage of disease. Sentinel node biopsy can be made more accurate and less morbid with novel adjuncts. Positive sentinel node biopsies are now rarely managed with completion lymphadenectomy. Should a patient require lymphadenectomy, immediate lymphatic reconstruction may mitigate the lymphedema risk. Finally, there are minimally invasive modalities for effective control of in-transit recurrences.

Electrochemotherapy of skin metastases from malignant melanoma: a PRISMA-compliant systematic review

The main treatment of MM metastases are systemic therapies, surgery, limb perfusion, and intralesional talimogene laherparepvec. Electrochemotherapy (ECT) is potentially useful also due to the high response rates recorded in cancers of any histology. No randomized studies comparing ECT with other local therapies have been published on this topic. We analyzed the available evidence on efficacy and toxicity of ECT in this setting. PubMed, Scopus, and Cochrane databases were screened for paper about ECT on MM skin metastases. Data about tumor response, mainly in terms of overall response rate (ORR), toxicity (both for ECT alone and in combination with systemic treatments), local control (LC), and overall survival (OS) were collected. The methodological quality was assessed using a 20-item validated quality appraisal tool for case series. Overall, 18 studies were included in our analysis. In studies reporting “per patient” tumor response the pooled complete response (CR) was 35.7% (95%CI 26.0–46.0%), and the pooled ORR was 80.6% (95%CI 68.7–90.1%). Regarding “per lesion” response, the pooled CR was 53.5% (95%CI 42.1–64.7%) and the pooled ORR was 77.0% (95%CI 56.0–92.6%). One-year LC rate was 80%, and 1-year OS was 67–86.2%. Pain (24.2–92.0%) and erythema (16.6–42.0%) were the most frequent toxicities. Two studies reported 29.2% and 41.6% incidence of necrosis. ECT is effective in terms of tumor response and tolerated in patients with skin metastases from MM, albeit with a wide variability of reported results. Therefore, prospective trials in this setting are warranted.

Double Trouble: Immunotherapy Doublets in Melanoma-Approved and Novel Combinations to Optimize Treatment in Advanced Melanoma

Immune checkpoint inhibitors, particularly anti-PD-1-based immune checkpoint inhibitors, have dramatically improved outcomes for patients with advanced melanoma and are currently deemed a standard of care. Ipilimumab/nivolumab is the first combination of immune checkpoint inhibitors to improve progression-free survival and overall survival in the first-line setting, with durable responses and the longest median overall survival, 72.1 months, of any drug therapy approved for advanced melanoma. However, its use is limited by the high rate of severe (grade 3-4) treatment-related adverse events. More recently, the novel immune checkpoint inhibitor combination of nivolumab/relatlimab (anti-PD-1/anti-LAG3) showed improved progression-free survival compared with nivolumab alone in the first-line setting and was well tolerated; thus, it is likely this combination will be added to the armamentarium as a first-line treatment for advanced melanoma. These changes in the treatment landscape have several treatment implications for decision-making. The choice of first-line systemic drug therapy, and the decision between immune checkpoint inhibitor monotherapy or combination therapy, requires a comprehensive assessment of disease-related factors and patient characteristics. Despite this striking progress, many patients' disease still progresses. Several new agents and therapeutic approaches are under investigation in clinical trials. Intralesional treatments hold promise for accessible metastases, although their broad application in the clinic will be limited. Prognostic and predictive biomarkers, as well as strategies to reduce treatment-related toxicities and overcome resistance, are required and are now the focus of clinical and translational research.

Management of In-Transit Metastases

PURPOSE OF REVIEW

The purpose of this study is to discuss the current knowledge and future perspectives regarding the treatment options for in-transit metastases (ITM), along with the optimal algorithms for patients presenting with this adverse manifestation of melanoma.

RECENT FINDINGS

In addition to procedures historically accepted for the management of ITM, encompassing surgery and regional techniques, novel medications in the form of immune checkpoint inhibitors (ICI) and targeted therapies now represent standard options, allowing for the possibility of combined approaches, with an expanding role of systemic therapies. Melanoma in-transit metastases consist of intralymphatic neoplastic implants distributed between the primary site and the regional nodal basin, within the subepidermal and dermal lymphatics. Distinct risk factors may influence the development of ITM, and the clinical presentation can be highly heterogeneous, enhancing the complexity of the management of ITM. Surgical resection, when feasible, continues to represent a standard approach for patients with curative intent. Patients with extensive or unresectable disease may also benefit from regional approaches that include isolated limb perfusion or infusion, electrochemotherapy, and a wide variety of intralesional therapies. Over the past decade, regimens with ICI and BRAF/MEK inhibitors dramatically expanded the benefit of systemic treatments for patients with melanoma, both in the adjuvant setting and for those with advanced disease, and the combination of these modalities with regional treatments, as well as neoadjuvant approaches, may represent the future for the treatment of patients with ITM.

Tumor MHC Class I Expression Associates with Intralesional Interleukin-2 Response in Melanoma

Cancer immunotherapy can result in lasting tumor regression, but predictive biomarkers of treatment response remain ill-defined. Here, we performed single-cell proteomics, transcriptomics, and genomics on matched untreated and interleukin-2 (IL-2) injected metastases from patients with melanoma. Lesions that completely regressed following intralesional IL-2 harbored increased fractions and densities of non-proliferating CD8+ T cells lacking expression of PD-1, LAG-3 and TIM-3 (PD-1-LAG-3-TIM-3-). Untreated lesions from patients who subsequently responded with complete eradication of all tumor cells in all injected lesions (individuals referred to herein as "extreme responders") were characterized by proliferating CD8+ T cells with an exhausted phenotype (PD-1+LAG-3+TIM-3+), stromal B-cell aggregates, and expression of IFNgamma and IL-2 response genes. Loss of membranous MHC class I expression in tumor cells of untreated lesions was associated with resistance to IL-2 therapy. We validated this finding in an independent cohort of metastatic melanoma patients treated with intralesional or systemic IL-2. Our study suggests that intact tumor cell antigen presentation is required for melanoma response to IL-2 and describes a multi-dimensional and spatial approach to develop immuno-oncology biomarker hypotheses using routinely collected clinical biospecimens.

Neoantigen-Reactive T Cells: The Driving Force behind Successful Melanoma Immunotherapy

Simple Summary

Cancer immunotherapy is a revolutionary type of cancer therapy. It uses the patient’s own immune system to fight and potentially cure cancer. The first major breakthrough of immunotherapy came from successful clinical trials for melanoma treatments. Since then, researchers have focused on understanding the science behind immunotherapy, so that patients with other types of cancer may also benefit. One of the major findings is that the T cells in melanoma patients may recognize a specific type of tumor antigen, called neoantigens, and then kill tumor cells that present these neoantigens. The neoantigens mainly arise from the DNA mutations found in tumor cells. These mutations are translated into mutated proteins that are then distinguished by T cells. In this article, we discuss the critical role of T cells in immunotherapy, as well as the clinical trials that shaped the treatments for melanoma.

Abstract

Patients with metastatic cutaneous melanoma have experienced significant clinical responses after checkpoint blockade immunotherapy or adoptive cell therapy. Neoantigens are mutated proteins that arise from tumor-specific mutations. It is hypothesized that the neoantigen recognition by T cells is the critical step for T-cell-mediated anti-tumor responses and subsequent tumor regressions. In addition to describing neoantigens, we review the sentinel and ongoing clinical trials that are helping to shape the current treatments for patients with cutaneous melanoma. We also present the existing evidence that establishes the correlations between neoantigen-reactive T cells and clinical responses in melanoma immunotherapy.

Injectable Therapies for Regional Melanoma

Patients with unresectable cutaneous, subcutaneous, or nodal melanoma metastases are often candidates for injectable therapies, which are attractive for ease of intralesional delivery to superficial metastases and limited systemic toxicity profiles. Injectable or intralesional therapies can be part of multifaceted treatment strategies to kill tumor directly or to alter the tumor so as to make it more sensitive to systemic therapy. Talimogene laherparepvec is the only Food and Drug Administration-approved injectable therapy currently in wide clinical use in the United States, although ongoing trials are evaluating novel intralesional agents as well as combinations with systemic therapies, particularly checkpoint inhibitors.

Clinical characteristics and therapy response in unresectable melanoma patients stage IIIB-IIID with in-transit and satellite metastases

INTRODUCTION

Cutaneous melanoma is notorious for the development of in-transit metastases (ITM). For unknown biological reasons, ITM remain the leading tumour manifestation without progression to distant sites in some patients.

METHODS

In total, 191 patients with initially unresectable stage III ITM and satellite metastases from 16 skin cancer centres were retrospectively evaluated for their tumour characteristics, survival and therapy response. Three groups according to disease kinetics (no distant progress, slow (>6 months) and fast (<6 months) distant progression) were analysed separately.

RESULTS

Median follow-up time was 30.5 (range 0.8-154.0) months from unresectable ITM. Progression to stage IV was observed in 56.5% of cases. Patients without distant metastasis were more often female, older (>70 years) and presented as stage III with lymph node or ITM at initial diagnosis in 45.7% of cases. Melanoma located on the leg had a significantly better overall survival (OS) from time of initial diagnosis compared to non-leg localised primaries (hazard ratio [HR] = 0.61, 95% confidence interval [CI] 0.40-0.91; p = 0.017), but not from diagnosis of unresectable stage III (HR = 0.67, 95% CI 0.45-1.02; p = 0.06). Forty percent of patients received local therapy for satellite and ITM. Overall response rate (ORR) to all local first-line treatments was 38%; disease control rate (DCR) was 49%. In total, 72.3% of patients received systemic therapy for unresectable stage IIIB-D. ORR for targeted therapy (n = 19) was highest with 63.2% and DCR was 84.2% compared to an ORR of 31.4% and a DCR of 54.3% in PD-1 treated patients (n = 70). Patients receiving PD-1 and intralesional talimogene laherparepvec (n = 12) had an ORR of 41.7% and a DCR of 75%.

CONCLUSION

Patients with unresectable ITM and without distant progression are more often female, older, and have a primary on the leg. Response to PD-1 inhibitors in this cohort was lower than expected, but further investigation is required to elucidate the biology of ITM development and the interplay with the immune system.

Case Report: Combined Intra-Lesional IL-2 and Topical Imiquimod Safely and Effectively Clears Multi-Focal, High Grade Cutaneous Squamous Cell Cancer in a Combined Liver and Kidney Transplant Patient

Cutaneous squamous cell carcinoma (cSCC) is the second most common non-melanoma skin cancer worldwide, with ever increasing incidence and mortality. While most patients can be treated successfully with surgical excision, cryotherapy, or radiation therapy, there exist a subset of patients with aggressive cSCC who lack adequate therapies. Among these patients are solid organ transplant recipients who due to their immunosuppression, develop cSCC at a dramatically increased rate compared to the normal population. The enhanced ability of the tumor to effectively undergo immune escape in these patients leads to more aggressive tumors with a propensity to recur and metastasize. Herein, we present a case of aggressive, multi-focal cSCC in a double organ transplant recipient to frame our discussion and current understanding of the immunobiology of cSCC. We consider factors that contribute to the significantly increased incidence of cSCC in the context of immunosuppression in this patient population. Finally, we briefly review current literature describing experience with localized therapies for cSCC and present a strong argument and rationale for consideration of an IL-2 based intra-lesional treatment strategy for cSCC, particularly in this immunosuppressed patient population.

In-transit metastatic cutaneous melanoma: current management and future directions

Management of in-transit melanoma encompasses a variety of possible treatment pathways and modalities. Depending on the location of disease, number of lesions, burden of disease and patient preference and characteristics, some treatments may be more beneficial than others. After full body radiographic staging is performed to rule out metastatic disease, curative therapy may be performed through surgical excision, intraarterial regional perfusion and infusion therapies, intralesional injections, systemic therapies or various combinations of any of these. While wide excision is limited in indication to superficial lesions that are few in number, the other listed therapies may be effective in treating unresectable disease. Where intraarterial perfusion based therapies have been shown to successfully treat extremity disease, injectable therapies can be used in lesions of the head and neck. Although systemic therapies for in-transit melanoma have limited specific data to support their primary use for in-transit disease, there are patients who may not be eligible for any of the other options, and current clinical trials are exploring the use of concurrent and sequential use of regional and systemic therapies with early results suggesting a synergistic benefit for oncologic response and outcomes.

Advances in Targeting Cutaneous Melanoma

Simple Summary

Cutaneous Melanoma (CM), arising from pigment-producing melanocytes in the skin, is an aggressive cancer with high metastatic potential. While cutaneous melanoma represents only a fraction of all skin cancers (<5%), it accounts for most skin-cancer-related deaths worldwide. Immune checkpoint inhibition has been the first therapeutic approach to significantly benefit patient survival after treatment. Nevertheless, the immunosuppressive tumor microenvironment and the intrinsic and acquired treatment resistance of melanoma remain crucial challenges. Combining local and systemic treatment offers the potential to augment therapeutic response and overcome resistance, although, complex drug combinations can harbor an increased risk of immune-related adverse events. The aim of this review is to give current insight into studies combining systemic and local therapeutic approaches to overcome drug resistance, prime melanoma cells for therapy, and improve overall treatment response in CM patients.

Abstract

To date, the skin remains the most common cancer site among Caucasians in the western world. The complex, layered structure of human skin harbors a heterogenous population of specialized cells. Each cell type residing in the skin potentially gives rise to a variety of cancers, including non-melanoma skin cancer, sarcoma, and cutaneous melanoma. Cutaneous melanoma is known to exacerbate and metastasize if not detected at an early stage, with mutant melanomas tending to acquire treatment resistance over time. The intricacy of melanoma thus necessitates diverse and patient-centered targeted treatment options. In addition to classical treatment through surgical intervention and radio- or chemotherapy, several systemic and intratumoral immunomodulators, pharmacological agents (e.g., targeted therapies), and oncolytic viruses are trialed or have been recently approved. Moreover, utilizing combinations of immune checkpoint blockade with targeted, oncolytic, or anti-angiogenic approaches for patients with advanced disease progression are promising approaches currently under pre-clinical and clinical investigation. In this review, we summarize the current ‘state-of-the-art’ as well as discuss emerging agents and regimens in cutaneous melanoma treatment.

State of Melanoma: An Historic Overview of a Field in Transition

The management of melanoma significantly improved within the last 25 years. Chemotherapy was the first approved systemic therapeutic approach and resulted in a median overall of survival less than 1 year, without survival improvement in phase III trials. High-dose interferon α2b and IL-2 were introduced for resectable high-risk and advanced disease, respectively, resulting in improved survival and response rates. The anti-CTLA4 and anti-programmed death 1 monoclonal antibodies along with BRAF/MEK targeted therapies are the dominant therapeutic classes of agent for melanoma. This article provides an historic overview of the evolution of melanoma management.

Injectables in Head and Neck Cutaneous Melanoma Treatment

Head and neck cutaneous melanomas pose many treatment challenges. Intratumoral injectables offer local and possibly systemic therapy in unresectable lesions. Talimogene laherparepvec, an injectable oncolytic type 1 herpes simplex virus, can improve durable response rates compared with systemic granulocyte-macrophage colony-stimulating factor therapy in patients with stage IIIB to IVM1a unresectable melanoma. These benefits were most noticed in lower-stage subsets and treatment naive patients. Efficacy of talimogene laherparepvec was maintained in patients with head and neck melanoma. Talimogene laherparepvec plus systemic immunotherapies is being studied, with promising preliminary data. Numerous ongoing clinical trials are investigating other viral and nonviral injectables.

Intratumoural immunotherapies for unresectable and metastatic melanoma: current status and future perspectives

The emergence of human intratumoural immunotherapy (HIT-IT) is a major step forward in the management of unresectable melanoma. The direct injection of treatments into melanoma lesions can cause cell lysis and induce a local immune response, and might be associated with a systemic immune response. Directly injecting immunotherapies into tumours achieves a high local concentration of immunostimulatory agent while minimising systemic exposure and, as such, HIT-IT agents are associated with lower toxicity than systemic immune checkpoint inhibitors (CPIs), enabling their potential use in combination with other therapies. Consequently, multiple HIT-IT agents, including oncolytic viruses, pattern-recognition receptor agonists, injected CPIs, cytokines and immune glycolipids, are under investigation. This review considers the current clinical development status of HIT-IT agents as monotherapy and in combination with systemic CPIs, and the practical aspects of administering and assessing the response to these agents. The future of HIT-IT probably lies in its use in combination with systemic CPIs; data from Phase 2 trials indicate a synergy between HIT-IT and CPIs. Data also suggest that the addition of HIT-IT to a CPI might generate responses in CPI-refractory tumours, thereby overcoming resistance and addressing a current unmet need in unresectable and metastatic melanoma for treatment options following progression after CPI treatment.

Evaluation of Intra-Lesional Interleukin 2 for the Treatment of In-Transit Melanoma Disease: L'évaluation de l'interleukine-2 intralésionnelle pour traiter les mélanomes en transit

Background

Intra-lesional interleukin 2 (IL-2) therapy trials for the treatment of in-transit melanoma using different treatment protocols have been published reporting varied results. This study assesses the results of IL-2 therapy in our institution and to evaluate the reproducibility of our response rates when using the same treatment protocol as another Canadian centre.

Methods

A retrospective review was undertaken of patients with in-transit melanoma who were treated with intralesional IL-2 in a single institution from 2010 to 2016. Responses were evaluated using RECIST criteria. Demographic data, tumour characteristics, follow-up data, in-transit-free interval, and survival data were collected and analysed.

Results

Forty-nine patients were identified. Overall tumour response rate was 72%, including complete response in 23 patients (47%) and partial response in 12 patients (24%). Stable disease was observed in 4% of patients and progressive disease in 25%. The main side effects were minor discomfort with injections and auto-limited flu-like symptoms. The presence of tumour-infiltrating lymphocytes may be a predictor of better response.

Conclusion

This study confirms prior experience with intra-lesional IL-2, demonstrating it to be an effective, safe, and well-tolerated therapy for in-transit melanoma. Tumour-infiltrating lymphocytes as a predictor of better response warrant further study.

Lesional therapies for in-transit melanoma

BACKGROUND AND OBJECTIVES

To describe the outcomes of lesional therapy of in-transit melanoma (ITM) with interleukin-2 (IL-2), diphencyprone (DPCP), combination lesional therapy (IL-2, retinoid, and imiquimod; CLT), and imiquimod.

METHODS

Data was collected for consecutive patients with ITM receiving lesional therapies from 2008 to 2018 in a retrospective review. Included patients did not have metastatic disease at time of starting on lesional therapy and were not on systemic therapy. The primary outcome was complete pathologic response (pCR).

RESULTS

Of 83 patients, 57 (69%) started treatment with IL-2, 10 (12%) with DPCP, 12 (14%) with CLT, and 4 (5%) with imiquimod. pCR was achieved in 34 patients (41%) overall, including 44% starting on IL-2, 20% on DPCP, 58% on CLT, and none on imiquimod (P = .024). With a median follow-up of 45 months, cumulative one-year overall survival was 86%, with the best survival in the CLT group. Forty-eight percent experienced common terminology criteria for adverse events grade 1 or 2 toxicity. A quarter of patients on DPCP discontinued therapy due to toxicity (P = .002).

CONCLUSIONS

IL-2 may be considered for the treatment of ITM with multiple or rapidly developing lesions where there would otherwise be significant morbidity with surgery, given pCR rates and toxicity.

Locoregional management of in-transit metastasis in melanoma: an Ontario Health (Cancer Care Ontario) clinical practice guideline

Objective

The purpose of this guideline is to provide guidance on appropriate management of satellite and in-transit metastasis (itm) from melanoma.

Methods

The guideline was developed by the Program in Evidence-Based Care (pebc) of Ontario Health (Cancer Care Ontario) and the Melanoma Disease Site Group. Recommendations were drafted by a Working Group based on a systematic review of publications in the medline and embase databases. The document underwent patient- and caregiver-specific consultation and was circulated to the Melanoma Disease Site Group and the pebc Report Approval Panel for internal review; the revised document underwent external review.

Recommendations

"Minimal itm" is defined as lesions in a location with limited spread (generally 1-4 lesions); the lesions are generally superficial, often clustered together, and surgically resectable. "Moderate itm" is defined as more than 5 lesions covering a wider area, or the rapid development (within weeks) of new in-transit lesions. "Maximal itm" is defined as large-volume disease with multiple (>15-20) 2-3 cm nodules or subcutaneous or deeper lesions over a wide area.■ In patients presenting with minimal itm, complete surgical excision with negative pathologic margins is recommended. In addition to complete surgical resection, adjuvant treatment may be considered.■ In patients presenting with moderate unresectable itm, consider using this approach for localized treatment: intralesional interleukin 2 or talimogene laherparepvec as 1st choice, topical diphenylcyclopropenone as 2nd choice, or radiation therapy as 3rd choice. Evidence is insufficient to recommend intralesional bacille Calmette- Guérin or CO2 laser ablation outside of a research setting.■ In patients presenting with maximal itm confined to an extremity, isolated limb perfusion, isolated limb infusion, or systemic therapy may be considered. In extremely select cases, amputation could be considered as a final option in patients without systemic disease after discussion at a multidisciplinary case conference.■ In cases in which local, regional, or surgical treatments for itm might be ineffective or unable to be performed, or if a patient has systemic metastases at the same time, systemic therapy may be considered.

Insights into the Molecular Mechanisms Behind Intralesional Immunotherapies for Advanced Melanoma

The incidence of cutaneous melanoma, a highly malignant skin cancer, is increasing yearly. While surgical removal of the tumor is the mainstay of treatment for patients with locally confined disease, those with metastases face uncertainty when it comes to their treatment. As melanoma is a relatively immunogenic cancer, current guidelines suggest using immunotherapies that can rewire the host immune response to target melanoma tumor cells. Intralesional therapy, where immunomodulatory agents are injected directly into the tumor, are an emerging aspect of treatment for in-transit melanoma because of their ability to mitigate severe off-target immune-related adverse events. However, their immunomodulatory mechanisms are poorly understood. In this review, we will summarize and discuss the different intralesional therapies for metastatic melanoma with respect to their clinical outcomes and immune molecular mechanisms.

The Landmark Series: Regional Therapy of Recurrent Cutaneous Melanoma

In-transit melanoma represents a distinct disease pattern in which melanoma recurs as dermal or subcutaneous nodules between the primary melanoma site and the draining regional lymph node basin. The disease pattern is often not amenable to complete surgical resection. Since the 1950s, regional therapies have been explored for the treatment of this disease entity, with the goal of maximizing delivery of the therapeutic agent to the tumor while minimizing systemic toxicity. We reviewed landmark studies describing and evaluating regional chemotherapy and intralesional therapies for patients with in-transit melanoma metastases.

Local and Recurrent Regional Metastases of Melanoma

Up to 10% of patients with cutaneous melanoma will develop recurrent locoregional disease. While surgical resection remains the mainstay of treatment for isolated recurrences, locoregional melanoma can often present as bulky, unresectable disease and can pose a significant therapeutic challenge. This chapter focuses on the natural history of local and regionally recurrent metastases and the multiple treatment modalities which exist for advanced locoregional melanoma, including regional perfusion procedures such as hyperthermic isolated limb perfusion and isolated limb infusion, intralesional therapies, and neo-adjuvant systemic therapy strategies for borderline resectable regional disease. Hyperthermic limb perfusion (HILP) and isolated limb infusion (ILI) are generally well-tolerated and have shown overall response rates between 44% and 90%. Intralesional therapies also appear to be well-tolerated as adverse events are usually limited to the site of injection and minor transient flu-like symptoms. Systemic targeted therapies have shown to have response rates up to 85% when used as neoadjuvant therapy in patients with borderline resectable disease. While combination immunotherapy in the neoadjuvant setting has also shown promising results, this data has not yet matured.

Neo-DREAM study investigating Daromun for the treatment of clinical stage IIIB/C melanoma

High-risk resectable melanoma poses therapeutic challenges as this subgroup remains most vulnerable for disease recurrence. Immunotherapy has established its efficacy in cases of advanced melanoma, and now is actively being investigated in the multimodal management of resectable disease. Daromun, an intralesional immunocytokine, has emerged as a unique immunotherapy in its ability to preferentially target tumor cells, resulting in direct destruction, while generating a bystander effect that leads to a distant treatment effect. On the basis of its mechanism of action, there is growing interest in delivering immune-based therapies in a neoadjuvant setting. In this review, the neo-DREAM study, a Phase III trial comparing the safety and efficacy of neoadjuvant Daromun for resectable stage IIIB/C melanoma will be described. Clinical Trial Registration Number: NCT03567889.

Management of Locoregionally Advanced Melanoma

Melanoma has a unique propensity for locoregional metastasis secondary to intralymphatic transit not seen in other cutaneous or soft tissue malignancies. Novel intralesional therapies using oncolytic immunotherapy exhibit increasing response rates with observed bystander effect. Intralesional modalities in combination with systemic immunotherapy are the subject of ongoing clinical trials. Regional therapy is used in isolated limb locoregional metastasis whereby chemotherapy is delivered to an isolated limb avoiding systemic side effects. Multimodal treatment strategy is imperative in the treatment of locoregionally advanced melanoma. One must be versed on these quickly evolving therapeutic options.

Topical and intralesional therapies for in-transitmelanoma

This report surveys the role of topical and intralesional agents in the management of in-transit melanoma. The extent and progression of in-transit disease is highly variable and many patients can have a protracted period of locoregional control. These agents are useful in the management of patients who have progressed beyond local surgical excision in whom more aggressive therapies, such as isolated limb infusion or use of talimogene laherparepvec, are not appropriate or have failed. In general, these agents are modestly effective and associated with frequent but only minor toxicity. As the mechanism of action of many of these agents includes initiation of a local immune response, combinations with immune checkpoint inhibitors are currently being explored.

Therapeutic vaccination immunomodulation: forming the basis of all cancer immunotherapy

Recent immunotherapy advances have convincingly demonstrated complete tumour removal with long-term survival. These impressive clinical responses have rekindled enthusiasm towards immunotherapy and tumour antigen vaccination providing 'cures' for melanoma and other cancers. However, many patients still do not benefit; sometimes harmed by severe autoimmune toxicity. Checkpoint inhibitors (anti-CTLA4; anti-PD-1) and interleukin-2 (IL-2) are 'pure immune drivers' of pre-existing immune responses and can induce either desirable effector-stimulatory or undesirable inhibitory-regulatory responses. Why some patients respond well, while others do not, is presently unknown, but might be related to the cellular populations being 'driven' at the time of dosing, dictating the resulting immune response. Vaccination is in-vivo immunotherapy requiring an active host response. Vaccination for cancer treatment has been skeptically viewed, arising partially from difficulty demonstrating clear, consistent clinical responses. However, this article puts forward accumulating evidence that 'vaccination' immunomodulation constitutes the fundamental, central, intrinsic property associated with antigen exposure not only from exogenous antigen (allogeneic or autologous) administration, but also from endogenous release of tumour antigen (autologous) from in-vivo tumour-cell damage and lysis. Many 'standard' cancer therapies (chemotherapy, radiotherapy etc.) create waves of tumour-cell damage, lysis and antigen release, thus constituting 'in-vivo vaccination' events. In essence, whenever tumour cells are killed, antigen release can provide in-vivo repeated vaccination events. Effective anti-tumour immune responses require antigen release/supply; immune recognition, and immune responsiveness. With better appreciation of endogenous vaccination and immunomodulation, more refined approaches can be engineered with prospect of higher success rates from cancer therapy, including complete responses and better survival rates.

Contemporary Approaches to In-Transit Melanoma

In-transit melanoma represents a distinct disease pattern of heterogeneous superficial tumors. Many treatments have been developed specifically for this type of disease, including regional chemotherapy and a variety of directly injectable agents. Novel strategies include the intralesional delivery of oncolytic viruses and immunocytokines. The combination of intralesional or regional chemotherapy with systemic immune checkpoint inhibitors also is a promising approach. In the current review, we examine the general management of the workup of patients with in-transit disease, the range of available therapies, and recommendations for specific therapies for an individual patient.

Management of in-transit melanoma metastases: a review

In-transit metastases (ITM) of cutaneous melanoma are locoregional recurrences confined to the superficial lymphatics that occur in 3.4-6.2% of patients diagnosed with melanoma. ITM are a heterogeneous disease that poses a therapeutic dilemma. Patients may have a prolonged disease trajectory involving multiple or repeat treatment modalities for frequent recurrences. The management of ITM has evolved without the development of a standardized protocol. Owing to the variability of the disease course there are few dedicated clinical trials, with a number of key trials in stage III melanoma excluding ITM patients. Thus, there is a paucity of quality data on the efficacy of the treatment modalities available for ITM and even fewer studies directly comparing modalities. At present the mainstay of ITM treatment is surgical resection, with intralesional therapies, isolated limb infusion and radiotherapy utilized as second-line measures. The developing role of targeted therapies and immunotherapy has yet to be explored completely in these patients. This review addresses the evidence base of the efficacy of the various treatment modalities available and those factors that have impacted their clinical uptake.

Do you know your guidelines? Diagnosis and management of cutaneous head and neck melanoma

The following article is the next installment of the series "Do You Know Your Guidelines?" presented by the Education Committee of the American Head and Neck Society. Guidelines for the prevention, diagnosis, workup, and management of cutaneous melanoma are reviewed in an evidence-based fashion.

Intralesional therapy as a treatment for locoregionally metastatic melanoma

INTRODUCTION

The emergence of novel intralesional therapies have dramatically changed the treatment landscape for melanoma. The heterogeneous presentation of melanoma continues to pose challenges for clinicians, especially when dealing with advanced locoregional disease. Intralesional therapies have the benefit of causing local tumor destruction, while minimizing systemic toxicity. Moreover, the integration of immunotherapeutic agents into intralesional compounds has resulted in the additional benefit of a bystander effect, whereby untreated distant lesions also derive a benefit from treatment. Intralesional therapy has assumed an important role in the management of unresectable, locoregional disease for melanoma. Areas covered: Multiple intralesional agents have been studied over the years, with only a few demonstrating promising results. This review will provide an overview of the different intralesional agents for melanoma. Mechanisms of action, clinical efficacy, and side effects will be the primary focus. Expert commentary: Treatment options for advanced melanoma continue to evolve. Attractive new therapies delivered by an intralesional route has demonstrated promising results, with minimal side effects. The ideal treatment strategy for melanoma will remain a multimodal approach; intralesional therapy provides an additional tool in the treatment armamentarium for melanoma.

A novel immunization strategy using cytokine/chemokines induces new effective systemic immune responses, and frequent complete regressions of human metastatic melanoma

Immune responses have been elicited by a variety of cancer vaccines, but seldom induce regressions of established cancers in humans. As a novel therapeutic immunization strategy, we tested the hypothesis that multiple cytokines/chemokines secreted early in secondary responses ex-vivo might mimic the secretory environment guiding new immune responses. The early development of immune responses is regulated by multiple cytokines/chemokines acting together, which at physiologic concentrations act locally in concert with antigen to have non-specific effects on adjacent cells, including the maturation of dendritic cells, homing and retention of T cells at the site of antigen, and the differentiation and expansion of T cell clones with appropriate receptors. We postulated that repeated injections into a metastasis of an exogenous chemokine/cytokine mixture might establish the environment of an immune response and allow circulating T cell clones to self- select for mutant neo-epitopes in the tumor and generate systemic immune responses. To test this idea we injected some metastases in patients with multiple cutaneous melanoma nodules while never injecting other control metastases in the same patient. New immune responses were identified by the development of dense lymphocytic infiltrates in never-injected metastases, and the frequent complete regression of never-injected metastases, a surprising observation. 70% of subjects developed dense infiltrates of cytotoxic CD8 cells in the center and margin of never-injected metastases; 38% of subjects had complete and often durable regressions of all metastases, without the use of check-point inhibitors, suggesting that, as a proof-of-principle, an immunization strategy can control advanced human metastatic melanoma.

Developments in Intralesional Therapy for Metastatic Melanoma

BACKGROUND

Locoregional advanced melanoma poses a complex clinical challenge that requires a multidisciplinary, patient-centered approach. Numerous agents have been studied for their suitability as intralesional therapy in the past decades, but few have successfully completed phase 3 clinical trial testing.

METHODS

The relevant medical literature was searched for articles regarding use of intralesional therapies in metastatic melanoma. Therapies with data from phase 2 or higher studies were selected for review. This review also summarizes the mechanisms of action, adverse-event profiles, and clinical data for these agents.

RESULTS

Intralesional therapies demonstrate promising effects in select patients with advanced melanoma. The optimal approach should be individually tailored and consist of a combination of intralesional therapies, regional perfusions, systemic immunotherapies, targeted therapies, and surgery, if necessary.

CONCLUSIONS

Due to its relatively good local response rates and tolerable adverse-event profile, intralesional therapy may be a treatment option for select patients with unresectable, locally advanced or metastatic melanoma.

The Role of Regional Therapies for in-Transit Melanoma in the Era of Improved Systemic Options

The incidence of melanoma has been increasing at a rapid rate, with 4%–11% of all melanoma recurrences presenting as in-transit disease. Treatments for in-transit melanoma of the extremity are varied and include surgical excision, lesional injection, regional techniques and systemic therapies. Excision to clear margins is preferred; however, in cases of widespread disease, this may not be practical. Historically, intralesional therapies were generally not curative and were often used for palliation or as adjuncts to other therapies, but recent advances in oncolytic viruses may change this paradigm. Radiation as a regional therapy can be quite locally toxic and is typically relegated to disease control and symptom relief in patients with limited treatment options. Regional therapies such as isolated limb perfusion and isolated limb infusion are older therapies, but offer the ability to treat bulky disease for curative intent with a high response rate. These techniques have their associated toxicities and can be technically challenging. Historically, systemic therapy with chemotherapies and biochemotherapies were relatively ineffective and highly toxic. With the advent of novel immunotherapeutic and targeted small molecule agents for the treatment of metastatic melanoma, the armamentarium against in-transit disease has expanded. Given the multitude of options, many different combinations and sequences of therapies can be offered to patients with in-transit extremity melanoma in the contemporary era. Reported response and survival rates of the varied treatments may offer valuable information regarding treatment decisions for patients with in-transit melanoma and provide rationale for these decisions.

Immunotherapy in Melanoma, Gastrointestinal (GI), and Pulmonary Malignancies

Oncologic immunotherapy involves stimulating the immune system to more effectively identify and eradicate tumor cells that have successfully adapted to survive the body's natural immune defenses. Immunotherapy has shown great promise thus far by prolonging the lives of patients with a variety of malignancies, and has added a crucial new set of tools to the oncologists' armamentarium. The aim of this paper is to provide an overview of immunotherapy treatment options that are currently available and under active research for melanoma, gastrointestinal (esophageal, gastric, pancreatic, and colorectal), and pulmonary malignancies. Potential biomarkers that may predict favorable responses to immunotherapies are discussed where applicable, as are future avenues of research in this rapidly evolving field.

Pathologic complete response to intralesional interleukin-2 therapy associated with improved survival in melanoma patients with in-transit disease

PURPOSE

Melanoma patients with in-transit disease have a high mortality rate despite various treatment strategies. The aim of this study was to validate the role of intralesional interleukin (IL)-2, to understand its mechanism of action, and to better understand factors that may influence its response.

METHODS

We retrospectively collected the clinicopathological data of 31 consecutive patients who presented to a tertiary care cancer center for treatment of in-transit melanoma with intralesional IL-2. Kaplan-Meier survival curves and multivariable Cox regression analysis were performed. Immunohistochemistry (IHC) was used to better understand the immune response to localized IL-2 therapy. Targeted next-generation sequencing was performed to genomically characterize the tumors.

RESULTS

Ten patients (10/31, 32 %) achieved a pathologic complete response (pCR), 17/21 (55 %) had a partial response, and 4/21 (19 %) had progressive disease on treatment. pCR to IL-2 therapy was associated with overall survival (log-rank p = 0.004) and improved progression-free survival (PFS) [adjusted hazard ratio (HR) 0.11; 95 % CI 0.02-0.47; p = 0.003). A higher CD8+ T cell infiltrate was identified in in-transit lesions with a pCR compared with the other lesions (mean IHC score 3.78 vs. 2.61; p = 0.01). Patients with an elevated CD8+ infiltrate demonstrated an improved PFS (unadjusted HR 0.08; 95 % CI 0.01-0.52; p = 0.008).

CONCLUSIONS

Thirty-two percent of patients achieved pCR with intralesional IL-2 therapy and had a significantly improved PFS compared with the rest of the cohort, which may be explained by a systemic CD8+ T-cell response.