In-transit Melanoma Metastases Research Articles

Rare Presentation of Melanoma Recurrences With Diffuse Subcutaneous Intravascular Lesions: A Novel In-Transit Metastases Pattern.

In 4%-11% of cases, melanoma recurrences present as in-transit (IT) metastases, and their prognosis is quite poor. Consequently, an early diagnosis and treatment of IT metastasis assume paramount significance. Despite this, the diagnosis of cutaneous IT metastases persistently presents a formidable challenge due to the diversity in clinical and dermoscopic characteristics. We provide a novel melanoma IT metastases pattern with interesting dermoscopic features and magnetic resonance imaging via presenting an unusual case characterized by diffuse subcutaneous intravascular lesions to supplement the understanding of cutaneous melanoma IT metastases.

The effect of a single dose of nivolumab prior to isolated limb perfusion for patients with in-transit melanoma metastases: An interim analysis of a phase Ib/II randomized double-blind placebo-controlled trial (NivoILP trial)

ObjectiveILP has shown to achieve high response rates in patients with melanoma ITM. Possibly there is a synergistic mechanism of action of ILP and anti-PD1. The aim of this trial was to investigate the safety and efficacy of adding a single dose of systemic anti-PD1 to isolated limb perfusion (ILP) for patients with melanoma in-transit metastases (ITM). MethodsIn this placebo controlled double-blind phase Ib/II trial, patients with melanoma ITM were randomized 1:1 to either a single systemic dose of nivolumab or placebo one day prior to ILP. The primary endpoint was complete response (CR) rate at three months, and safety in terms of incidence and severity of adverse events (AEs). ResultsA total of 20 patients were included. AEs of any grade occurred in 90% of patients in the nivolumab arm and in 80% in the placebo arm within three months after ILP. Grade 3 AEs were reported in 40% and 30% respectively, most commonly related to wound infection, wound dehiscence, or skin necrosis. There were no grade 4 or 5 AEs reported. The CR rate was 75% in the nivolumab arm and 60% in the placebo arm. The 1-year local progression-free rate was 86% in the nivolumab arm and 67% in the placebo arm. The 1-year OS was 100% in both arms. ConclusionFor patients with melanoma ITM, the addition of a single systemic dose of nivolumab the day before ILP is considered safe and feasible with promising efficacy. Accrual will continue in a phase 2 trial.

Isolated hyperthermic perfusions for cutaneous melanoma in-transit metastasis of the limb and uveal melanoma metastasis to the liver.

Patients with cutaneous melanoma can develop in-transit metastases (ITM), most often localized to limbs. For patients with uveal melanoma that develop metastatic disease, the overall majority develop isolated liver metastases. For these types of metastases, regional cancer therapies have evolved as effective treatments. Isolated limb perfusion (ILP), isolated limb infusion (ILI), isolated hepatic perfusion (IHP) and percutaneous hepatic perfusion (PHP) achieve a high local concentration of chemotherapy with minimal systemic exposure. This review discusses the mechanism and available literature on locoregional treatment modalities in the era of modern immunotherapy.

Tumour burden and female sex is negatively associated with health-related quality of life in melanoma patients with in-transit metastases

Background: Approximately 5% of patients with melanoma develop in-transit metastases, defined as recurrent metastases in superficial lymphatic vessels between the primary melanoma and the regional lymph node basin. Studies investigating health-related quality of life (HRQOL) in patients with melanoma have mostly combined stage III patients without considering the potential impact specifically associated with in-transit metastases on HRQOL. The aim of this study is to describe and identify factors associated with HRQOL in patients with melanoma in-transit metastases.

Effects of the Introduction of Modern Immunotherapy on the Outcome of Isolated Limb Perfusion for Melanoma In-Transit Metastases.

Isolated limb perfusion (ILP) is an effective locoregional treatment for melanoma in-transit metastasis, but the advent of modern effective immunotherapy, such as ICI (immune checkpoint inhibitors), has changed the treatment landscape. The primary aims of this study were to compare the characteristics of the patient population receiving ILP before and after the introduction of modern systemic treatments and to assess if outcomes after ILP were influenced by previous immunotherapy treatment. A single-centre analysis of patients that underwent ILP for melanoma in-transit metastasis between 2010 and 2021 was conducted, with patients grouped and compared by treatment time period: pre-ICI era (2010-2014) and ICI era (2017-2021). 218 patients were included. Patients undergoing ILP in the ICI era were slightly older (median age 73 vs. 68 years) compared to the pre-ICI era, with no other difference found. The overall response rate (ORR) was 83% vs. 84% and the complete response (CR) rate was 52% vs. 47% for the pre-ICI era and the ICI era, respectively. For patients that had received and failed immunotherapy prior to ILP (n = 20), the ORR was 75% and the CR rate was 50%. Melanoma-specific survival has improved, with a 3-year survival rate of 54% in the pre-ICI era vs. 86% in the ICI era. The patient population undergoing ILP for in-transit melanoma is largely unchanged in the current era of effective systemic treatments. Response rates have not decreased, and prior ICI treatment did not affect response rates, making ILP still a valid treatment option for this patient group.

Tumor Burden and Health-Related Quality of Life in Patients with Melanoma In-Transit Metastases.

Few studies have investigated the health-related quality of life (HRQOL) in patients with melanoma in-transit metastases (ITM). The aim was to investigate the association between tumor burden and HRQOL, including disparities pertaining to sex and age, in treatment-naïve patients with ITM. Functional Assessment of Cancer Therapy-Melanoma (FACT-M) questionnaire was used to assess HRQOL Pairwise comparisons using t-tests between clinical cutoffs are presented and multiple linear regression analysis showing the unique associations of gender, age, number of tumors, tumor size, presence of lymph node metastases, and tumor localization. A total of 95 patients, 47% females and 53% males (median age 72 years) were included between 2012 and 2021. Women scored significantly lower on emotional well-being (p = 0.038) and lower on FACT-M (p = 0.058). Patients who had ≥10 tumors scored significantly lower on FACT-M (p = 0.015), emotional- and functional well-being (p = 0.04, p = 0.004, respectively), melanoma scale (p = 0.005), and FACT-G (p = 0.027). There was no significant difference in HRQOL depending on age, size of tumors, localization, or presence of lymph node metastases. For patients with melanoma ITMs, the female sex and higher tumor burden (i.e., number of tumors) were significantly correlated with lower HRQOL. However, these findings do not fully explain HRQOL for this patient population, and future research should consider the possibility that there are specific questions for patients with ITM where current instruments might fail to measure their discomfort to the full extent.

The efficacy of immune checkpoint blockade for melanoma in-transit with or without nodal metastases: A multicenter cohort study.

9569 Background: Guidelines addressing melanoma in-transit metastasis (ITM) recommend immune checkpoint inhibitors (ICI) as a first-line treatment option, despite the fact that there are no efficacy data available from prospective trials for exclusively ITM disease. The aim of this study was to analyze the outcome of patients with ITM treated with ICI based on data from a large cohort of patients treated at international high‐volume melanoma centers. Methods: A multicenter retrospective cohort study of patients treated between January 2015 and December 2020 from Australia, Europe, and USA, evaluating treatment with ICI for ITM with or without nodal involvement (AJCC8 N1c, N2c and N3c) and without distant disease (M0). Patients were treated with PD-1 inhibitor (nivolumab or pembrolizumab) and/or CTLA-4 inhibitor (ipilimumab). We assessed response rates, progression-free survival (PFS), melanoma-specific survival (MSS) and overall survival (OS). Results: A total of 287 patients from 21 institutions in 8 countries were included. Immunotherapy was first-line treatment in 64 (22%) patients. Monotherapy with a PD-1 or CTLA-4 inhibitor was given in 233 (81%) and 23 (8%) patients respectively, while 31 (11%) received both in combination. Overall response rate was 56%, complete response (CR) rate 36% and progressive disease (PD) rate 32%. Median PFS was 10 months (95% CI 7.4-12.6 months) with a 1-, 2- and 5-year PFS rate of 48%, 33% and 18% respectively. Median MSS was not reached, and the 1-, 2- and 5-year MSS rates were 95%, 83% and 71% respectively. Conclusions: Systemic immunotherapy is an effective treatment for melanoma ITM. Future studies should evaluate the optimal role for systemic immunotherapy in the context of multimodality therapy including locoregional treatments such as surgery, intralesional therapy, and regional therapies.

The efficacy of immune checkpoint blockade for melanoma in-transit with or without nodal metastases – A multicenter cohort study

PurposeGuidelines addressing melanoma in-transit metastasis (ITM) recommend immune checkpoint inhibitors (ICI) as a first-line treatment option, despite the fact that there are no efficacy data available from prospective trials for exclusively ITM disease. The study aims to analyze the outcome of patients with ITM treated with ICI based on data from a large cohort of patients treated at international referral clinics. MethodsA multicenter retrospective cohort study of patients treated between January 2015 and December 2020 from Australia, Europe, and the USA, evaluating treatment with ICI for ITM with or without nodal involvement (AJCC8 N1c, N2c, and N3c) and without distant disease (M0). Treatment was with PD-1 inhibitor (nivolumab or pembrolizumab) and/or CTLA-4 inhibitor (ipilimumab). The response was evaluated according to the RECIST criteria modified for cutaneous lesions. ResultsA total of 287 patients from 21 institutions in eight countries were included. Immunotherapy was first-line treatment in 64 (22%) patients. PD-1 or CTLA-4 inhibitor monotherapy was given in 233 (81%) and 23 (8%) patients, respectively, while 31 (11%) received both in combination. The overall response rate was 56%, complete response (CR) rate was 36%, and progressive disease (PD) rate was 32%. Median PFS was ten months (95% CI 7.4–12.6 months) with a one-, two-, and five-year PFS rate of 48%, 33%, and 18%, respectively. Median MSS was not reached, and the one-, two-, and five-year MSS rates were 95%, 83%, and 71%, respectively. ConclusionSystemic immunotherapy is an effective treatment for melanoma ITM. Future studies should evaluate the role of systemic immunotherapy in the context of multimodality therapy, including locoregional treatments such as surgery, intralesional therapy, and regional therapies.

Management of In-Transit Metastases.

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. 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.

Isolated Limb Perfusion for the Treatment of Unresectable In- Transit Metastases of Cutaneous Squamous Cell Carcinoma

Squamous cell carcinoma (SCC) is the second most common non-melanoma skin cancer and its incidence has been increasing over the past decades. SCC in-transit metastases are rare and predict a poor prognosis. We present the case of a 69-year-old patient with a right lower leg SCC, surgically excised with free margins. One month later, erythematous to violaceous, firm papules begin to erupt on the right lower leg, evolving to ulcerated nodules over a period of weeks. Homolateral inguinal and iliac nodal metastases were documented by percutaneous biopsy of an inguinal palpable lymph node and later documented by positron emission tomography – computed tomography (PET-CT). Given the unresectability of the disease, regional chemotherapy involving isolated limb perfusion (ILP) with melphalan and tumor necrosis factor-alpha (TNFα) was performed in order to avoid amputation. Macroscopic regression ensued, with complete resolution of all visible in-transit metastases 12 weeks after perfusion. However, a fatal outcome was observed 4 months later, due to systemic metastases. ILP is an effective and well-established technique in the treatment of advanced tumors of the extremities. Its main indications are in-transit metastases of malignant melanoma and advanced soft tissue sarcomas. However, studies have shown its effectiveness in other tumors such as locally advanced SCC. Despite the unfortunate outcome, it was possible to avoid amputation of the limb, with complete local disease remission.

Anti-PD-1 checkpoint blockade improves the efficacy of a melphalan-based therapy in experimental melanoma

IntroductionThe induction of adaptive cellular immunity in patients with in-transit melanoma metastasis treated with hyperthermic isolated limb perfusion (ILP) with melphalan has been shown to contribute to the effectiveness of the therapy. Activated CD8+ T cells appear to be of particular importance for the efficacy of melphalan-based ILP therapy, as observed in both patients and animal models. In this study, we explored the possible synergistic effects of combining melphalan-based therapy with the checkpoint inhibitor anti-PD-1 on tumours in a mouse melanoma model. MethodsA murine vaccination model that utilized melphalan-exposed melanoma cells was used to mimic certain immunological features of melphalan-based ILP. The effects of the vaccine on tumour growth and PD-1 expression on CD8+ tumour-infiltrating T cells were analyzed. The melphalan-based vaccine was then combined with an anti-PD-1 antibody and tumour growth was assessed. ResultsTreatment with melphalan-based therapy significantly induced the expression of PD-1 on CD8+ tumour-infiltrating lymphocytes. Combination therapy using melphalan-based therapy followed by treatment with PD-1 antibodies significantly reduced early-stage tumour growth relative to monotherapies and no treatment. ConclusionsThis study thus suggests that the addition of PD-1 blockade to melphalan-based therapies, such as ILP, may be therapeutically beneficial.

Improved detection of in-transit metastases of malignant melanoma with BSREM reconstruction in digital [18F]FDG PET/CT

ObjectivesTo compare block sequential regularized expectation maximization (BSREM) and ordered subset expectation maximization (OSEM) for the detection of in-transit metastasis (ITM) of malignant melanoma in digital [18F]FDG PET/CT.MethodsWe retrospectively analyzed a cohort of 100 [18F]FDG PET/CT scans of melanoma patients with ITM, performed between May 2017 and January 2020. PET images were reconstructed with both OSEM and BSREM algorithms. SUVmax, target-to-background ratio (TBR), and metabolic tumor volume (MTV) were recorded for each ITM. Differences in PET parameters were analyzed with the Wilcoxon signed-rank test. Differences in image quality for different reconstructions were tested using the Man-Whitney U test.ResultsBSREM reconstruction led to the detection of 287 ITM (39% more than OSEM). PET parameters of ITM were significantly different between BSREM and OSEM reconstructions (p < 0.001). SUVmax and TBR were higher (76.5% and 77.7%, respectively) and MTV lower (49.5%) on BSREM. ITM missed with OSEM had significantly lower SUVmax (mean 2.03 vs. 3.84) and TBR (mean 1.18 vs. 2.22) and higher MTV (mean 2.92 vs. 1.01) on OSEM compared to BSREM (all p < 0.001).ConclusionsBSREM detects significantly more ITM than OSEM, owing to higher SUVmax, higher TBR, and less blurring. BSREM is particularly helpful in small and less avid lesions, which are more often missed with OSEM.Key Points• In melanoma patients, [18F]FDG PET/CT helps to detect in-transit metastases (ITM), and their detection is improved by using BSREM instead of OSEM reconstruction.• BSREM is particularly useful in small lesions.

Treatment of in-transit melanoma metastases using intralesional PV-10

Melanoma in-transit metastases (ITMs) can sometimes be difficult to manage by surgical excision due to their number, size or location. Treatment by intralesional injection of PV-10, a 10% solution of rose bengal, has been reported to be a simple, safe and effective alternative, but more outcome data are required to confirm its value in the management of ITMs. Two hundred and twenty-six melanoma ITMs in 48 patients were treated with intralesional PV-10 supplied under a special-access scheme. By 8 weeks a complete response in all injected ITMs was achieved in 22 patients (46%) and a partial response in 19 patients (40%). Of 19 patients who had uninjected metastases, 3 (16%) had a response in these. The most common adverse event was transient localised pain in injected tumours. New ITMs developed in 25 patients within 8 weeks, and later in another 8 patients. Repeat injection cycles were given to 21 patients: 13 of these received repeat injection into partially responding or nonresponding tumours, 5 had new ITMs, as well as partially-responding lesions injected, and 3 received injection into new ITMs only. Twenty-two patients received subsequent systemic therapy. At 1 year 37 of the 48 patients were alive, 28 with melanoma, and at 2 years 27 were alive, and 19 with melanoma. Injection of PV-10 was simple and safe and resulted in tumour involution in most patients and sometimes in noninjected tumours. However, many patients developed new lesions; these were treated by further PV-10 injections or with alternative therapies.

Quantitative and Spatial Analysis of CD8+/PD-1 Tumor-Infiltrating Lymphocytes as a Predictive Biomarker for Clinical Response of Melanoma In-Transit Metastases to Topical Immunotherapy

BackgroundMelanoma in-transit metastases (ITMs) are a challenge to treat and associated with systemic disease and poor prognosis. Topical diphencyprone (DPCP), a potent contact sensitizer, is an established treatment for melanoma ITMs. This exploratory study investigated the utility of BRAF mutation status, CD8, PD-1, PD-L1, and TILs distribution as biomarkers for response of ITMs to topical immunotherapy (DPCP).MethodsThe ITM deposits of 40 patients treated with DPCP were subjected to biomarker analysis for BRAF status, CD8 and PD-1 expression on tumor-infiltrating lymphocytes (TILs), and tumor PD-L1 expression. Response to DPCP and overall survival (OS) were compared by biomarker status.ResultsAfter 12 weeks, 10 patients (25%) had a complete response, 12 patients (30%) had a partial response, and 18 patients (45%) had no response. No significant association was found between any individual biomarker and response to DPCP or OS. The BRAF mutation rate was 25% (10/40). All the patients with a complete response had BRAF wild-type tumor. Peritumoral CD8+ T-cells were associated with complete response (P = 0.041). Both CD8+ and PD-1 expressions were highly correlated (P < 0.0001), and the highest levels of PD-1 expression were detected at the peritumoral interface (P = 0.0004). Only two cases were PD-L1-positive, and both had a complete response to DPCP (P = 0.043).ConclusionPatients who have BRAF wild-type tumor are more likely to experience a complete response to DPCP. Peritumoral TILs and PD-1 expressions may predict a better response to DPCP. Expression of PD-L1 may be associated with a complete response to DPCP. A larger prospective study is required.

Isolated Limb Perfusion in the Treatment of In-Transit Melanoma Metastases: Are There Predictive Factors for the Outcome?

Introduction: Isolated limb perfusion (ILP) with delivery of high dose melphalan proved to be efficient in the treatment of in-transit metastases (ITM). Preoperative factors may carry an impact on patient outcome, including in-field or local progression-free survival (IPFS), time to distant metastases (TDM) and overall survival (OS). Materials and Methods: A retrospective analysis of 83 patients who underwent an ILP at our institution before the era of efficient upfront systemic therapy in high-risk cases. Patients were classified according to a modified M.D. Anderson score, with relevance for the outcome: 34 stage III A (patients with satellites and/or ITM), 31 stage III AB (patients with synchronous regional lymph node metastases and satellites and/or ITM), 11 at a new stage labelled III A(B) which takes into account a previous history of therapeutic regional node dissection and actual recurrence in the limb only, and 7 stage IV (metastatic cases with actual major problem of recurrence in the limb). Results: Our median follow-up time was 90.1 months (IQR 72.8-151.6). Median IPFS was 16.3 months (95% CI 9.5-78.5), median TDM 28.8 months (95% CI 15.4-69.6) and median OS 34.6 months (95% CI 21.1-59.5). The strongest significant prognostic factor regarding IPFS was LND before ILP (p=0.02). However, sex (p=0.03/0.07), LND before ILP (p=0.004/0.11) and some primary tumor characteristics (Clark level (p=0.15/0.07) and ulceration (p=0.006/0.04)) were prognostic regarding TDM and / or OS. Conclusion: ILP with melphalan can provide long-term regional and systemic tumor control in a selected group of patients and should be kept in mind for patients recurring after local surgery or radiotherapy and resistant to or ineligible for the newer systemic therapies.

First Eastern European Experience of Isolated Limb Infusion for In-Transit Metastatic Melanoma Confined to the Limb: Is it still an Effective Treatment Option in the Modern Era?

Background: isolated limb infusion (ILI) with cytotoxic agents has demonstrated to be a simple and effective treatment option for patients with melanoma in-transit metastases (ITM) confined to an extremity. Data of ILI performed in Europe are scarce and to date no Eastern European ILI experience has been published. Therefore, the aim of the current study was to evaluate the efficacy of ILI in Estonia.

International Multi-Center Experience of Isolated Limb Infusion for In-Transit Melanoma Metastases in the Octogenarian Patient

International Multi-Center Experience of Isolated Limb Infusion for In-Transit Melanoma Metastases in the Octogenarian Patient

Isolated limb perfusion with melphalan activates interferon-stimulated genes to induce tumor regression in patients with melanoma in-transit metastasis

ABSTRACT Hyperthermic isolated limb perfusion (ILP) with high-dose melphalan is a treatment option for melanoma patients with metastasis confined to limbs (in-transit metastasis). The therapy entails a complete response (CR) rate of 50–70%. Cellular immunity is proposed to impact on the clinical efficacy of ILP, but the detailed aspects of ILP-induced immune activation remain to be explored. For this study, we explored the potential role of interferon-stimulated gene (ISG) products, including CXCL10, CCL2, PD-L2 and IFN-γ along with expression of their cognate receptors CXCR3, CCR4, CCR5 and PD-1 on lymphocytes, for the clinical efficacy of ILP. Patients with high serum levels of CXCL10, CCL2, PD-L2 and IFN-γ were more likely to achieve CR after ILP. Additionally, the expression of CXCR3, CCR4 and CCR5 on T cells and/or natural killer (NK) cells was enhanced by ILP. Peripheral blood mononuclear cells (PBMCs) secreted high levels of CXCL10, CCL2 and IFN-γ in response to co-culture with melphalan-exposed melanoma cells in vitro. Activated T cells migrated toward supernatants from these co-cultures. Furthermore, melphalan-exposed melanoma cells triggered upregulation of CXCR3, CCR4, CCR5 and PD-1 on co-cultured T cells and/or NK cells. Our results suggest that constituents released from melphalan-exposed melanoma cells stimulate the ISG axis with ensuing formation of chemokines and upregulation of chemokine receptor expression on anti-neoplastic immune cells, which may contribute in ILP-induced tumor regression.

First Eastern European experience of isolated limb infusion for in-transit metastatic melanoma confined to the limb: Is it still an effective treatment option in the modern era?

BackgroundIsolated limb infusion (ILI) with cytotoxic agents is a simple and effective treatment option for patients with melanoma in-transit metastases (ITMs) confined to an extremity. Data for ILIs performed in Europe are sparse and to date no Eastern European ILI experience has been reported. The aim of the current study was to evaluate the efficacy of ILI in Estonia. Patients and methodsData for twenty-one patients were collected and analysed. All patients had melanoma ITMs and underwent an ILI between January 2012 and May 2018. The cytotoxic drug combination of melphalan and actinomycin-D was used. Drug circulation times were 20–30 min under mildly hyperthermic conditions (38–39 °C). Primary outcome measures were treatment response and overall survival. ResultsNineteen lower limb and two upper limb ILIs were performed. The female to male ratio was 18:3. The overall response rate (complete + partial response) was 76% (n = 16), with a complete response in 38% (n = 8). The overall long-term limb salvage rate was 90% (n = 19). During follow-up, eight patients (38%) died, two due to metastatic melanoma. Five-year overall survival was 57%. ConclusionThis first Eastern European report of ILI for melanoma ITMs shows results comparable to those from other parts of the world. In this era of effective targeted and immune therapies, ILI remains a useful treatment option, with a high overall response rate and durable responses in patients with melanoma ITMs confined to a limb.

The Prognosis and Natural History of In-Transit Melanoma Metastases at a High-Volume Centre.

Patients with in-transit melanoma metastases (ITM) experience a diverse spectrum of clinical presentations and a highly variable disease course. There is no standardized treatment protocol for these patients due to the limited data comparing treatment modalities for ITM. This is the first study to describe the disease trajectory and natural history of a large cohort of patients with ITM. A retrospective study of patients treated for ITM between 2004 and 2018 at the Peter MacCallum Cancer Centre was performed. Clinical and pathological characteristics for primary and in-transit episodes were analyzed for predictors of relapse-free survival (RFS), distant metastasis-free survival (DMFS), and melanoma-specific survival. A total of 109 patients with 303 episodes of ITM were identified: 52 (48%) females, median age 70.1years (range 35-92). The median RFS for all episodes was 5months (95% confidence interval [CI] 4.2-5.7). Eighty-seven percent of episodes involving isolated in-transit lesions underwent surgical excision, compared with 17% involving more than five in-transit lesions. A trend was seen between a greater number of lesions and shorter RFS (p = 0.055). The median DMFS was 34.8months (95% CI 22.8-51.6). Factors associated with shorter DMFS included primary tumor thickness (hazard ratio [HR] 1.08, 95% CI 1.01-1.15; p = 0.026), site of primary tumor (p = 0.008), and BRAF mutation (HR 2.12, 95% CI 1.14-3.94; p = 0.018). Locoregional relapse is common in patients with ITM regardless of treatment modality. Characteristics of the ITM may predict for RFS, while primary tumor characteristics remain important predictors of DMFS.