Contemporary Approaches to In-Transit Melanoma

Treatment strategies with electrochemotherapy for limb in-transit melanoma: Real-world outcomes from a European, retrospective, cohort study

BACKGROUND

This study analysed treatment strategies with electrochemotherapy (ECT) in melanoma with limb in-transit metastases (ITM).

METHODS

We audited AJCC v.8 stage IIIB-IIID patients treated across 22 centres (2006-2020) within the International Network for Sharing Practices of ECT (InspECT).

RESULTS

452 patients were included, 58 % pre-treated (93 % had lower limb ITM, 44 % had ≤10 metastases [median size 1.5 cm]. Treatment strategies included first-line ECT (n = 145, 32 %), ECT with concurrent locoregional/systemic treatment (n = 163, 36 %), and salvage ECT (n = 144, 32 %). The objective response rate was 63 % (complete response [CR], 24 %), increasing to 74 % (CR, 39 %) following retreatment (median two ECT, range 1-8). CR rate in treatment-naïve and pre-treated patients was 50 % vs 32 % (p < 0.001). Bleomycin de-escalation was associated with lower CR (p = 0.004). Small tumour number and size, hexagonal electrode, retreatment, and post-ECT skin ulceration predicted response in multivariable analysis. At a median follow-up of 61 months, local and locoregional recurrence occurred in 55 % and 81 % of patients. Median local progression-free, new lesions-free, and regional recurrence-free survival were 32.9, 6.9, and 7.7 months. Grade-3 toxicity was 15 %. Concurrent treatment and CR correlated with improved regional control and survival. Concomitant checkpoint inhibition did not impact toxicity or survival outcomes. The median overall survival was 5.7 years.

CONCLUSIONS

Among patients with low-burden limb-only ITM, standard-dose bleomycin ECT results in durable local response. Treatment naivety, low tumour volume, hexagonal electrode application, retreatment, and post-ECT ulceration predict response. CR and concurrent treatment correlate with improved regional control and survival outcomes. Combination with checkpoint inhibitors is safe but lacks conclusive support.

Recent advancements in the diagnosis and treatment of acral melanoma

Acral melanoma (AM) is the most common histologic subtype of melanoma in dark-skinned patients and is associated with a worse prognosis and a high mortality rate, largely due to the inconspicuous nature of early-stage lesions, which can lead to late diagnosis. Because of the overlapping clinical and histopathological features of AM with other forms of cutaneous melanomas, early detection of AM requires a multidisciplinary approach that integrates various diagnostic modalities, including clinical examination, dermoscopy, histopathology, molecular testing, radiological imaging, and blood tests. While surgery is the preferred method of treatment for AM, other therapeutic options may be employed based on the stage and underlying etiology of the disease. Immune checkpoint inhibitors, molecular targeted therapy, radiotherapy, chemotherapy, and oncolytic virotherapy represent promising advanced treatment options for AM. In this review, we provide an overview of the latest advancements in diagnostic and therapeutic methods for AM, highlighting the importance of early detection and the prompt, individualized management of this challenging disease.

Prognostic factors for satellitosis or in-transit metastasis in cutaneous squamous cell carcinoma: A multicentric cohort study

BACKGROUND

Satellitosis or in-transit metastasis (S-ITM) has clinical outcomes comparable to node-positivity in cutaneous squamous cell carcinoma (cSCC). There is a need to stratify the risk groups.

OBJECTIVE

To determine which prognostic factors of S-ITM confer an increased risk of relapse and cSCC-specific-death.

METHODS

A retrospective, multicenter cohort study. Patients with cSCC developing S-ITM were included. Multivariate competing risk analysis evaluated which factors were associated with relapse and specific death.

RESULTS

Of a total of 111 patients with cSCC and S-ITM, 86 patients were included for analysis. An S-ITM size of ≥20 mm, >5 S-ITM lesions, and a primary tumor deep invasion was associated with an increased cumulative incidence of relapse (subhazard ratio [SHR]: 2.89 [95% CI, 1.44-5.83; P = .003], 2.32 [95% CI, 1.13-4.77; P = .021], and 2.863 [95% CI, 1.25-6.55; P = .013]), respectively. Several >5 S-ITM lesions were also associated with an increased probability of specific death (SHR: 3.48 [95% CI, 1.18-10.2; P = .023]).

LIMITATIONS

Retrospective study and heterogeneity of treatments.

CONCLUSION

The size and the number of S-ITM lesions confer an increased risk of relapse and the number of S-ITM an increased risk of specific-death in patients with cSCC presenting with S-ITM. These results provide new prognostic information and can be considered in the staging guidelines.

Burden of Care for Patients With In-Transit Melanoma

INTRODUCTION

Patient burden of cancer care can be significant, especially for cancers like melanoma where patients are living longer, even with advanced disease. The purpose of this study is to compare the burden of treatment of melanoma patients with in-transit metastases (ITM). There are multiple treatment options for ITM, but no standard due to lack of large cohort comparative studies; thus, the anticipated burden of care may influence therapy choice.

METHODS

Included patients had in-transit melanoma without distant metastasis and were managed at our institution from July 1, 2015 through December 31, 2020 using a combination of surgery, systemic, intralesional, and radiation therapy. We compared treatment burden, (number of treatments, clinic visits, inpatient hospital days, and distance traveled) and response rates using Kruskal-Wallis and chi-squared tests. Recurrence-free survival and estimated charges were exploratory endpoints.

RESULTS

There were 42 patients who met the inclusion criteria. As initial treatment, patients had surgery (n = 20), surgery with adjuvant (n = 6), systemic (n = 9), and intralesional therapy (n = 2). Surgery had the lowest treatment burden (median of 1 treatment, 3 clinic visits, and 0 inpatient days) while surgery with adjuvant systemic therapy had the highest burden (median of 13 treatments, 12 clinic visits, and 0 inpatient days). Systemic, intralesional, and radiation therapy were used more often for recurrent ITM. Travel distance (P = 0.88) and response rates did not statistically differ between the four options for first line therapy (P = 0.99). At a median follow-up time of 8.8 mo, 22 (52%) of the cohort required more than 1 therapy to manage recurrent or progressive disease and 14 (33%) progressed to distant disease.

CONCLUSIONS

Treatment of in-transit melanoma is associated with high burden of care and often requires multiple therapies, even with maximally effective first treatment choice. Factors evaluated in this study may be used to set expectations of treatment course for newly diagnosed patients and may aid in patients' decisions on therapy selection.

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.

Health-related quality of life trajectories in melanoma patients after electrochemotherapy: real-world insights from the InspECT register

BACKGROUND

Electrochemotherapy (ECT) effectively controls skin metastases from cutaneous melanoma.

OBJECTIVES

This study aimed to evaluate health-related quality of life (HRQoL) in melanoma patients pre-/post-ECT and its effect on treatment outcome.

METHODS

The analysis included prospective data from the International Network for Sharing Practices of ECT register. Following the Standard Operating Procedures, patients received intravenous or intratumoural bleomycin (15,000 IU/m2 ; 1000 IU mL/cm3 ) followed by 100-microsecond, 1000-V/cm electric pulses. Endpoints included response (RECIST v3.0), local progression-free survival (LPFS), toxicity (CTCAE v5.0), and patient-reported HRQoL at baseline, one, two, four and ten months (EuroQol [EQ-5D-3L], including 5-item utility score [EQ-5D] and visual analogue scale for self-reported health state [EQ-VAS]). Comparisons within/between subgroups were made for statistical and minimal important differences (MID). HRQoL scores and clinical covariates were analysed to identify predictors of response in multivariate analysis.

RESULTS

Median tumour size was 2 cm. Complete response rate, G3 toxicity and one-year LPFS in 378 patients (76% of the melanoma cohort) were 47%, 5%, and 78%. At baseline, age-paired HRQoL did not differ from the general European population. Following ECT, both EQ-5D and EQ-VAS scores remained within MID boundaries, particularly among complete responders. A subanalysis of the EQ-5D items revealed a statistically significant deterioration in pain/discomfort and mobility (restored within four months), and self-care and usual activities (throughout the follow-up) domains. Concomitant checkpoint inhibition correlated with better EQ-5D and EQ-VAS trajectories. Baseline EQ-5D was the exclusive independent predictor for complete response (RR 14.76, p=0.001).

CONCLUSIONS

HRQoL of ECT melanoma patients parallels the general population and is preserved in complete responders. Transient deterioration in pain/discomfort and mobility and persistent decline in self-care and usual activities may warrant targeted support interventions. Combination with checkpoint inhibitors is associated with better QoL outcomes. Baseline HRQoL provides predictive information which can help identify patients most likely to respond.

Recognizing Recurrence of Melanoma in an Emergency Department Patient: A Case Study

Malignant melanoma incidence is rising faster than any other malignancy. Recurrent disease can occur in as many as 10% of patients diagnosed with primary malignant melanoma. In-transit melanoma is a type of locoregional disease that materializes when the cancer recurs as dermal and subdermal nodules found between the primary site and the lymph node drainage basin. Patients may not recognize the lesions as in-transit melanoma, and they may present to the emergency department for another matter completely. Ultimately, once recurrence is suspected, there must be a swift referral to oncology. Lack of recognition of this unique skin lesion could prove to be fatal. As frontline providers of care, emergency nurse practitioners should be alert to the characteristics of these lesions and the history that supports this dermatological condition.

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.

Oncolytic viruses in melanoma

Malignant melanoma recurrence remains heterogeneous in presentation, ranging from locoregional disease (i.e., local recurrence, satellites, in transit disease) to distant dermal and visceral metastases. This diverse spectrum of disease requires a personalized approach to management and has resulted in the development of both local (e.g., surgery, radiation, intralesional injection) and systemic (intravenous or oral) treatment strategies. Intralesional agents such as oncolytic viruses may also evoke local immune stimulation to induce and enhance the antitumor immune response. Further, it is hypothesized that these oncolytic viruses may convert immunologically "cold" tumors to more reactive "hot" tumor microenvironments and thereby overcome anti-PD-1 therapy resistance. Currently, talimogene laherparepvec (T-VEC), a modified herpes virus, is FDA-approved in this population, with many other oncolytic viruses under investigation in both preclinical and trial settings. Herein, we detail the scientific rationale, current landscape, and future directions of oncolytic viruses in melanoma.

A Prospective Study of Intraarterial Infusion Chemotherapy in Advanced Wild-Type BRAF Melanoma Patients

BACKGROUND

Treatment strategies for advanced cutaneous melanoma (CM) patients, resistant or not treatable with novel target and immunotherapeutic drugs, remain a significant challenge, particularly for patients with unresectable stage IIIC/D disease localized to inferior limbs and pelvis, for whom specific outcomes are rarely considered.

MATERIALS AND METHODS

This is a prospective study of multidisciplinary treatments, including locoregional melphalan chemotherapy, in 62 BRAF wild-type CM patients with locoregional metastases in the inferior limbs and pelvis, including inguinal regions. Patients were either in progression following or ineligible for, or not treatable with novel immunotherapy. For exclusively inferior limb-localised disease, patients received locoregional melphalan chemotherapy performed by hyperthermic isolated limb perfusion (n = 19) or isolated limb infusion (n = 19), and for synchronous lesions localised to inferior limbs and pelvis, received hypoxic pelvic and limb perfusion (n = 24). Additional multidisciplinary therapy included local, locoregional and systemic treatments and the primary endpoint was tumour response.

RESULTS

The objective response rate following first cycle of locoregional chemotherapy was 37.1% at 3 mo and median progression-free survival was 4-mo, with 12.9% procedure-related complications, 30.6% low-grade haematological toxicity and 11.3% severe limb toxic tissue reactions. Multivariate logistic regression showed that the odds of response were significantly higher for patients ≤ 75 y of age and for patients with locoregional metastases exclusively located in the inferior limbs.

CONCLUSION

In this subgroup of CM patients with BRAF wild-type status, locoregional metastases localized to inferior limbs and pelvis, in progression following or ineligible for immunotherapy, melphalan locoregional chemotherapy demonstrated a safe and effective profile.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT01920516; date of trial registration: August 6, 2013.

Application of an indocyanine green surgical fluorescence imaging system in sentinel lymph node biopsy of acral malignant melanoma

Background

Regional lymph node status is an independent influencing factor for the prognosis of acral malignant melanoma, and the accuracy of sentinel lymph node biopsy (SLNB) is directly related to the judgment of regional lymph node status. This study aimed to explore the application value of indocyanine green (ICG) surgical fluorescence imaging system in the SLNB of acral malignant melanoma.

Methods

A total of 34 patients with acral malignant melanoma were admitted to the Department of Burn and Plastic Surgery in Jiangsu Provincial People’s Hospital from January 2020 to March 2020. Among these patients, 22 required SLNB. ICG and methylene blue (MB) were combined to intraoperatively trace the sentinel lymph nodes (SLNs). The total number of SLNs detected during the operation was counted. We compared the number, detection rate, as well as the detection rate and false negative rate of positive SLNs of SLNs detected by ICG, MB, and ICG combined with MB.

Results

A total of 56 SLNs were detected in the 22 patients, among which 55 were detected by ICG (98%), 41 were detected by MB (71%), and 56 (100%) were detected by ICG combined with MB, and the average number of SLNs were 2.5, 1.64, and 2.55, respectively. A total of nine SLNs were detected, of which nine were detected by ICG (100%), seven by MB (78%), and nine by ICG combined with MB (100%). Patients with negative SLNs had no recurrence at the 6-month follow-up.

Conclusions

Compared with MB, the ICG fluorescent imaging system can improve the detection rate of SLNs in patients with acral malignant melanoma. Also, ICG combined with MB was superior to ICG alone.

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.

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

OBJECTIVES

To 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.

METHODS

We 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.

RESULTS

BSREM 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).

CONCLUSIONS

BSREM 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.

Molecular Aspects of the Isolated Limb Infusion Procedure

For decades, isolated limb infusion (ILI) and hyperthermic isolated limb perfusion (HILP) have been used to treat melanoma in-transit metastases and unresectable sarcoma confined to the limb utilizing the effect of loco-regional high-dose chemotherapy to the isolated limb. Both procedures are able to provide high response rates in patients with numerous or bulky lesions in whom other loco-regional treatments are becoming ineffective. In comparison to systemic therapies, on the other hand, ILI and HILP have the advantage of not being associated with systemic side-effects. Although in principle ILI and HILP are similar procedures, ILI is technically simpler to perform and differs from HILP in that it takes advantage of the hypoxic and acidotic environment that develops in the isolated limb, potentiating anti-tumour activity of the cytotoxic agents melphalan +/− actinomycin-D. Due to its simplicity, ILI can be used in both preclinical and clinical studies to test new cytotoxic regimens and combinations with the aim to overcome tumour resistance. In the future, administration of cytotoxic agents by ILI, in combination with systemic treatments such as BRAF/MEK/KIT inhibitors, immunotherapy (CTLA-4 blockade), and/or programmed death (PD-1) pathway inhibitors, has the potential to improve responses further by inducing increased tumour cell death while limiting the ability of the tumour to suppress the immune response.

Pediatric Melanoma-Diagnosis, Management, and Anticipated Outcomes

Melanoma is the most common skin cancer in children, often presenting in an atypical fashion. The incidence of melanoma in children has been declining. The mainstay of therapy is surgical resection. Sentinel lymph node biopsy often is indicated to guide therapy and determine prognosis. Completion lymph node dissection is recommended in selective cases after positive sentinel lymph node biopsy. Those with advanced disease receive adjuvant systemic treatment. Because children are excluded from melanoma clinical trials, management is based on pediatric retrospective data and adult clinical trials. This review focuses on epidemiology, presentation, surgical management, adjuvant therapy, and outcomes of pediatric melanoma.

Effectiveness of preoperative ultrasound-guided charcoal tattooing for localization of metastatic melanoma

Purpose

Excision of metastatic lesions is an important treatment strategy in patients with malignant melanoma, both at the initial diagnosis and upon recurrence. Since nonpalpable lesions cannot be easily visualized in the surgical field, we evaluated the effectiveness of ultrasound (US)-guided tattooing using a charcoal suspension for the localization of nonpalpable metastatic lesions of malignant melanoma.

Methods

Between November 2009 and June 2019, we retrospectively reviewed 65 nonpalpable lesions in 29 patients with malignant melanoma who underwent preoperative US-guided tattooing using a charcoal suspension for histologically confirmed or suspected metastases. The characteristics of the tattooed lesions were analyzed. The effectiveness of the procedure was evaluated based on the detection rate in the surgical field and the presence or absence of residua on postoperative follow-up US. Procedure-related complications were also analyzed.

Results

Of 65 lesions, 33 (50.8%) were histologically confirmed as metastases before the tattooing procedure, while the other 32 were suspected of being metastases based on imaging studies. The mean lesion size was 9.8 mm (range, 1.3 to 24.4 mm). The final pathology revealed metastases in 59 lesions (90.8%), including lymph node (n=51), muscle (n=5), and in-transit (n=3) metastases. Sixty-one lesions (93.8%) were successfully detected intraoperatively and removed without residua on follow-up US. Four residual lesions were removed after repeated localization (n=2) or by intraoperative US (n=2). No relevant complications were noted.

Conclusion

Preoperative US-guided tattooing localization can safely and effectively delineate nonpalpable metastatic melanoma lesions to aid in successful surgical excision.

Neoadjuvant immunotherapy with combined ipilimumab and nivolumab in patients with melanoma with primary or in transit disease

The introduction of new therapeutic agents has revolutionized the treatment of metastatic melanoma. The approval of adjuvant anti-programmed death-1 monotherapy with nivolumab or pembrolizumab, and dabrafenib plus trametinib has recently set a new landmark in the treatment of stage III melanoma. Now, clinical trials have shown that immune checkpoint blockade can be performed in a neoadjuvant setting, an approach established as a standard therapeutic approach for other tumour entities such as breast cancer. Recent studies suggest that a pathological response achieved by neoadjuvant immunotherapy is associated with long-term tumour control and that short neoadjuvant application of checkpoint inhibitors may be superior to adjuvant therapy. Most recently, neoadjuvant ipilimumab plus nivolumab in stage III melanoma was reported. With two courses of dose-optimized ipilimumab (1 mg kg^-1 ) combined with nivolumab (3 mg kg^-1 ), pathological responses were observed in 77% of patients, while only 20% of patients experienced grade 3 or 4 adverse events. However, the neoadjuvant trials employing combined immune checkpoint blockade conducted so far have excluded patients with in transit metastases, a common finding in stage III melanoma. Here we report four patients with in transit metastases or an advanced primary tumour who have been treated with neoadjuvant ipilimumab plus nivolumab according to the OpACIN-neo trial scheme (arm B). All patients achieved radiological disease control and a pathological response. None of the patients has relapsed so far. Linked Comment: Blankenstein and van Akkooi. Br J Dermatol 2020; 183:421-422.

Improved durable responses regardless of age following cytoreduction and "no-tourniquet" hyperthermic isolated limb chemotherapy for in transit melanoma of the extremity

BACKGROUND

In-transit metastatic melanoma of the extremity is a clinically aggressive disease. For patients with disease confined to the limb, regional chemotherapy remains an effective option. However, no studies thus far have included cytoreduction or perfusion/infusion without using a limb tourniquet as part of the operative procedure. We hypothesize that combining cytoreduction with no-tourniquet HILP/HILI is safe in patients of all ages and results in durable responses.

METHODS

A retrospective analysis was performed of a prospectively collected database of patients with in-transit malignant melanoma who underwent cytoreduction and HILP/HILI between 2013 and 2017. The primary endpoint was RECIST response at 3-12 months. Secondary endpoints included length of hospital stay, adverse effects, overall survival, and time to recurrence. A subgroup analysis was performed in patients ≥80 years old.

RESULTS

HILP patients had significantly higher disease burdens than HILI patients. Complete response rates for HILP and HILI were 95% and 75%, respectively at 3 months and 47% and 50%, respectively at 1 year (50% for patients >80) with 100% 1-year survival rates for both HILP and HILI patients. Three-year survival rates were 57% (HILP), 52% (HILI) and 68% (patients >80 years old). The average length of stay for all patients was 3.6 ± 1.4 days.

CONCLUSION

Combining cytoreduction with no-tourniquet HILP/HILI for in-transit metastatic melanoma of the extremity resulted in 100% survival regardless of age at 1 year and 68% 3-year survival in patients over 80 without any increase in adverse events.

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

BACKGROUND

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.

METHODS

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.

RESULTS

A total of 109 patients with 303 episodes of ITM were identified: 52 (48%) females, median age 70.1 years (range 35-92). The median RFS for all episodes was 5 months (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 34.8 months (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).

CONCLUSIONS

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.

Efficacy of Talimogene Laherparepvec (T-VEC) Therapy in Patients with In-Transit Melanoma Metastasis Decreases with Increasing Lesion Size

BACKGROUND

Talimogene laherparepvec (T-VEC) is the first injectable oncolytic viral therapy approved for in-transit melanoma metastasis, with a reported overall response rate (ORR) of 25% and complete response rate (CRR) of 10%. To ascertain the role of patient selection on outcomes in routine practice, we evaluated the impact of patient, lesion, and treatment factors on clinical response.

METHODS

Medical records were extracted for patients with recurrent stage IIIB-IV melanoma completing T-VEC at Duke University Medical Center between 1 January 2016 and 1 September 2018. Kaplan-Meier analysis assessed time to response and survival, while logistic regression measured associations of clinicopathologic status, lesion burden, T-VEC dosing, and use of prior and concurrent therapy with ORR and CRR.

RESULTS

Of 27 patients, an objective response was observed in 11 (40.7%), including one patient with partial response (3.7%) and 10 with complete response (37.0%). Time to complete response and overall response was a median 22 weeks (95% confidence interval [CI] 2.0-41.9 weeks and 15.8-28.2 weeks, respectively), and median progression-free survival was 17 weeks (95% CI 0-36 weeks). Logistic regression demonstrated each millimeter increase in maximum lesion diameter predicted decreased ORR (odds ratio [OR] 0.866, 95% CI 0.753-0.995; p = 0.04). Stage IV disease (OR 0.04, 95% CI 0.00-0.74; p = 0.031) and programmed death-1 inhibitor treatment (OR 0.06, 95% CI 0.01-0.74; p = 0.028) also predicted reduced clinical response.

CONCLUSIONS

This study corroborates recent data suggesting response rates to T-VEC may be higher than reported in clinical trials, arising in part from patient selection. T-VEC lesion diameter was persistently associated with clinical response and is a readily assessed predictor of successful T-VEC therapy.