Interferon-gamma signature as prognostic and predictive marker in macroscopic stage III melanoma

BACKGROUND

A substantial proportion of patients with macroscopic stage III melanoma do not benefit sufficiently from adjuvant anti-PD-1 therapy, as they either recur despite therapy or would never have recurred. To better inform adjuvant treatment selection, we have performed translational analyses to identify prognostic and predictive biomarkers.

PATIENTS AND METHODS

Two cohorts of patients with macroscopic stage III melanoma from an ongoing biobank study were included. Clinical data were compared between an observation cohort (cohort 1) and an adjuvant intention cohort (cohort 2). RNA sequencing for translational analyses was performed and treatment subgroups (cohort 1A and cohort 2A) were compared for possible biomarkers, using a cut-off based on the treatment-naïve patients. In addition, two validation cohorts (Melanoma Institute Australia (MIA) and University Medical Centre Utrecht (UMCU)) were obtained.

RESULTS

After a median follow-up of 26 months of the 98 patients in our discovery set, median recurrence-free survival (RFS) was significantly longer for the adjuvant intention cohort (cohort 2, n=49) versus the observation cohort (cohort 1, n=49). Median overall survival was not reached for either cohort, nor significantly different. In observation cohort 1A (n=24), RFS was significantly longer for patients with high interferon-gamma (IFNγ) score (p=0.002); for adjuvant patients of cohort 2A (n=24), a similar trend was observed (p=0.086). Patients with high B cell score had a longer RFS in cohort 1A, but no difference was seen in cohort 2A. The B cell score based on RNA correlated with CD20+ cells in tumor area but was not independent from the IFNγ score. In the MIA validation cohort (n=44), longer RFS was observed for patients with high IFNγ score compared with low IFNγ score (p=0.046), no difference in RFS was observed according to the B cell score. In both the observation (n=11) and the adjuvant (n=11) UMCU validation cohorts, no difference in RFS was seen for IFNγ and B cell.

CONCLUSIONS

IFNγ has shown to be a prognostic marker in both patients who were and were not treated with adjuvant therapy. B cell score was prognostic but did not improve accuracy over IFNγ. Our study confirmed RFS benefit of adjuvant anti-PD-1 for patients with macroscopic stage III melanoma.

Prognostic and predictive value of non-steroidal anti-inflammatory drugs in the EORTC 1325/KEYNOTE-054 phase III trial of pembrolizumab versus placebo in resected high-risk stage III melanoma

BACKGROUND

Pain is common in patients with cancer. The World Health Organisation recommends paracetamol or non-steroidal anti-inflammatory drugs (NSAIDs) for mild pain and combined with other agents for moderate/severe pain. This study estimated associations of NSAIDs with recurrence-free survival (RFS), distant metastasis-free survival (DMFS) and the incidence of immune-related adverse events (irAEs) in high-risk patients with resected melanoma in the EORTC 1325/KEYNOTE-054 phase III clinical trial.

PATIENTS AND METHODS

Patients with AJCC7 stage IIIA, IIIB or IIIC resected melanoma were randomized to receive 200 mg of adjuvant pembrolizumab (N = 514) or placebo (N = 505) 3-weekly for one year or until recurrence. As previously reported, pembrolizumab prolonged RFS and DMFS. NSAID use was defined as administration between 7 days pre-randomization and starting treatment. Multivariable Cox and Fine and Gray models were used to estimate hazard ratios (HRs) for associations of NSAIDs with RFS, DMFS and irAEs.

RESULTS

Of 1019 patients randomized, 59 and 44 patients in the pembrolizumab and placebo arms, respectively, used NSAIDs. NSAIDs were not associated with RFS (HR 0.91, 95% CI 0.58-1.43) or DMFS in the pembrolizumab (HR 1.03, 95% CI 0.65-1.66) or placebo arms (for RFS, HR 0.76, 95% CI 0.48-1.20; for DMFS, HR 0.80, 95% CI 0.49-1.31). NSAIDs were associated with the incidence of irAEs in the placebo arm (HR 3.06, 95% CI 1.45-6.45) but not in the pembrolizumab arm (HR 0.94, 95% CI 0.58-1.53).

CONCLUSION

NSAIDs were not associated with efficacy outcomes nor the risk of irAEs in patients with resected high-risk stage III melanoma receiving adjuvant pembrolizumab.

Development and validation of a novel model to predict recurrence-free survival and melanoma-specific survival after sentinel lymph node biopsy in patients with melanoma: an international, retrospective, multicentre analysis

BACKGROUND

The introduction of adjuvant systemic treatment for patients with high-risk melanomas necessitates accurate staging of disease. However, inconsistencies in outcomes exist between disease stages as defined by the American Joint Committee on Cancer (8th edition). We aimed to develop a tool to predict patient-specific outcomes in people with melanoma rather than grouping patients according to disease stage.

METHODS

Patients older than 13 years with confirmed primary melanoma who underwent sentinel lymph node biopsy (SLNB) between Oct 29, 1997, and Nov 11, 2013, at four European melanoma centres (based in Berlin, Germany; Amsterdam and Rotterdam, the Netherlands; and Warsaw, Poland) were included in the development cohort. Potential predictors of recurrence-free and melanoma-specific survival assessed were sex, age, presence of ulceration, primary tumour location, histological subtype, Breslow thickness, sentinel node status, number of sentinel nodes removed, maximum diameter of the largest sentinel node metastasis, and Dewar classification. A prognostic model and nomogram were developed to predict 5-year recurrence-free survival on a continuous scale in patients with stage pT1b or higher melanomas. This model was also calibrated to predict melanoma-specific survival. Model performance was assessed by discrimination (area under the time-dependent receiver operating characteristics curve [AUC]) and calibration. External validation was done in a cohort of patients with primary melanomas who underwent SLNB between Jan 30, 1997, and Dec 12, 2013, at the Melanoma Institute Australia (Sydney, NSW, Australia).

FINDINGS

The development cohort consisted of 4071 patients, of whom 2075 (51%) were female and 1996 (49%) were male. 889 (22%) had sentinel node-positive disease and 3182 (78%) had sentinel node-negative disease. The validation cohort comprised 4822 patients, of whom 1965 (41%) were female and 2857 (59%) were male. 891 (18%) had sentinel node-positive disease and 3931 (82%) had sentinel node-negative disease. Median follow-up was 4·8 years (IQR 2·3-7·8) in the development cohort and 5·0 years (2·2-8·9) in the validation cohort. In the development cohort, 5-year recurrence-free survival was 73·5% (95% CI 72·0-75·1) and 5-year melanoma-specific survival was 86·5% (85·3-87·8). In the validation cohort, the corresponding estimates were 66·1% (64·6-67·7) and 83·3% (82·0-84·6), respectively. The final model contained six prognostic factors: sentinel node status, Breslow thickness, presence of ulceration, age at SLNB, primary tumour location, and maximum diameter of the largest sentinel node metastasis. In the development cohort, for the model's prediction of recurrence-free survival, the AUC was 0·80 (95% CI 0·78-0·81); for prediction of melanoma-specific survival, the AUC was 0·81 (0·79-0·84). External validation showed good calibration for both outcomes, with AUCs of 0·73 (0·71-0·75) and 0·76 (0·74-0·78), respectively.

INTERPRETATION

Our prediction model and nomogram accurately predicted patient-specific risk probabilities for 5-year recurrence-free and melanoma-specific survival. These tools could have important implications for clinical decision making when considering adjuvant treatments in patients with high-risk melanomas.

FUNDING

Erasmus Medical Centre Cancer Institute.

Neo-Adjuvant Therapy for Metastatic Melanoma

Melanoma treatment is leading the neo-adjuvant systemic (NAS) therapy field. It is hypothesized that having the entire tumor in situ, with all of the heterogeneous tumor antigens, allows the patient's immune system to have a broader response to the tumor in all its shapes and forms. This translates into a higher clinical efficacy. Another benefit of NAS therapy potentially includes identifying patients who have a favorable response, which could offer an opportunity for the de-escalation of the extent of surgery and the need for adjuvant radiotherapy and/or adjuvant systemic therapy, as well as tailoring the follow-up in terms of the frequency of visits and cross-sectional imaging. In this paper, we will review the rationale for NAS therapy in resectable metastatic melanoma and the results obtained so far, both for immunotherapy and for BRAF/MEKi therapy, and discuss the response assessment and interpretation, toxicity and surgical considerations. All the trials that have been reported up to now have been investigator-initiated phase I/II trials with either single-agent anti-PD-1, combination anti-CTLA-4 and anti-PD-1 or BRAF/MEK inhibition. The results have been good but are especially encouraging for immunotherapies, showing high durable recurrence-free survival rates. Combination immunotherapy seems superior, with a higher rate of pathologic responses, particularly in patients with a major pathologic response (MPR = pathologic complete response [pCR] + near-pCR [max 10% viable tumor cells]) of 60% vs. 25-30%. The SWOG S1801 trial has recently shown a 23% improvement in event-free survival (EFS) after 2 years for pembrolizumab when giving 3 doses as NAS therapy and 15 as adjuvant versus 18 as adjuvant only. The community is keen to see the first results (expected in 2024) of the phase 3 NADINA trial (NCT04949113), which randomized patients between surgery + adjuvant anti-PD-1 and two NAS therapy courses of a combination of ipilimumab + nivolumab, followed by surgery and a response-driven adjuvant regimen or follow-up. We are on the eve of neo-adjuvant systemic (NAS) therapy, particularly immunotherapy, becoming the novel standard of care for macroscopic stage III melanoma.

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)

OBJECTIVE

ILP 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).

METHODS

In 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).

RESULTS

A 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.

CONCLUSION

For 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.

Population-Based Validation of the MIA and MSKCC Tools for Predicting Sentinel Lymph Node Status

Importance

Patients with melanoma are selected for sentinel lymph node biopsy (SLNB) based on their risk of a positive SLN. To improve selection, the Memorial Sloan Kettering Cancer Center (MSKCC) and Melanoma Institute Australia (MIA) developed predictive models, but the utility of these models remains to be tested.

Objective

To determine the clinical utility of the MIA and MSKCC models.

Design, Setting, and Participants

This was a population-based comparative effectiveness research study including 10 089 consecutive patients with cutaneous melanoma undergoing SLNB from the Swedish Melanoma Registry from January 2007 to December 2021. Data were analyzed from May to August 2023.

Main Outcomes and Measures,

The predicted probability of SLN positivity was calculated using the MSKCC model and a limited MIA model (using mitotic rate as absent/present instead of count/mm2 and excluding the optional variable lymphovascular invasion) for each patient. The operating characteristics of the models were assessed and compared. The clinical utility of each model was assessed using decision curve analysis and compared with a strategy of performing SLNB on all patients.

Results

Among 10 089 included patients, the median (IQR) age was 64.0 (52.0-73.0) years, and 5340 (52.9%) were male. The median Breslow thickness was 1.8 mm, and 1802 patients (17.9%) had a positive SLN. Both models were well calibrated across the full range of predicted probabilities and had similar external area under the receiver operating characteristic curves (AUC; MSKCC: 70.8%; 95% CI, 69.5-72.1 and limited MIA: 69.7%; 95% CI, 68.4-71.1). At a risk threshold of 5%, decision curve analysis indicated no added net benefit for either model compared to performing SLNB for all patients. At risk thresholds of 10% or higher, both models added net benefit compared to SLNB for all patients. The greatest benefit was observed in patients with T2 melanomas using a threshold of 10%; in that setting, the use of the nomograms led to a net reduction of 8 avoidable SLNBs per 100 patients for the MSKCC nomogram and 7 per 100 patients for the limited MIA nomogram compared to a strategy of SLNB for all.

Conclusions and Relevance

This study confirmed the statistical performance of both the MSKCC and limited MIA models in a large, nationally representative data set. However, decision curve analysis demonstrated that using the models only improved selection for SLNB compared to biopsy in all patients when a risk threshold of at least 7% was used, with the greatest benefit seen for T2 melanomas at a threshold of 10%. Care should be taken when using these nomograms to guide selection for SLNB at the lowest thresholds.

Role of Concurrent Ultrasound Surveillance of Sentinel Node-Positive Node Fields in Melanoma Patients Having Routine Cross-Sectional Imaging

PURPOSE

In sentinel node-positive (SN+ve) melanoma patients, active surveillance with regular ultrasound examination of the node field has become standard, rather than completion lymph node dissection (CLND). A proportion of these patients now receive adjuvant systemic therapy and have routine cross-sectional imaging (computed tomography [CT] or positron emission tomography [PET]/CT). The role of concurrent ultrasound (US) surveillance in these patients is unclear. The purpose of our study was to describe the modality of detection of nodal recurrence in SN+ve node fields.

METHODS

SN+ve melanoma patients who did not undergo CLND treated at a single institution from January 1, 2016 to December 31, 2020 were included.

RESULTS

A total of 225 SN+ve patients with a median follow-up of 23 months were included. Of these, 119 (53%) received adjuvant systemic therapy. Eighty (36%) developed a recurrence at any site; 24 (11%) recurred first in the SN+ve field, of which 12 (5%) were confirmed node field recurrence only at 2 months follow-up. The nodal recurrences were first detected by ultrasound in seven (3%), CT in seven (3%), and PET/CT in seven (3%) patients. All nodal recurrences evident on US were also evident on PET/CT and vice versa.

CONCLUSIONS

The high rate of recurrences outside the node field and the identification of all US-detected nodal recurrences on concurrent cross-sectional imaging modalities suggest that routine concurrent ultrasound surveillance of the node-positive field may be unnecessary for SN+ve melanoma patients having routine cross-sectional imaging.

The difficulty with measuring the largest melanoma tumour diameter in sentinel lymph nodes

Identification of sentinel node (SN) metastases can set the adjuvant systemic therapy indication for stage III melanoma patients. For stage IIIA patients, a 1.0 mm threshold for the largest SN tumour diameter is used. Therefore, uniform reproducible measurement of its size is crucial. At present, the number of deposits or their microanatomical sites are not part of the inclusion criteria for adjuvant treatment. The goal of the current study was to show examples of the difficulty of measuring SN melanoma tumour diameter and teach how it should be measured. Histopathological slides of SN-positive melanoma patients were retrieved using the Dutch Pathology Registry (PALGA). Fourteen samples with the largest SN metastasis around 1.0 mm were uploaded via tele-pathology and digitally measured by 12 pathologists to reflect current practice of measurements in challenging cases. Recommendations as educational examples were provided. Microanatomical location of melanoma metastases was 1 subcapsular, 2 parenchymal and 11 combined. The smallest and largest difference in measurements were 0.24 mm and 4.81 mm, respectively. 11/14 cases (78.6%) showed no agreement regarding the 1.0 mm cut-off. The median discrepancy for cases ≤5 deposits was 0.5 mm (range 0.24-0.60, n=3) and 2.51 mm (range 0.71-4.81, n=11) for cases with ≥6 deposits. Disconcordance in measuring SN tumour burden is correlated with the number of deposits. Awareness of this discordance in challenging cases, for example, cases with multiple small deposits, is important for clinical management. Illustrating cases to reduce differences in size measurement are provided.

Real-world relapse-free survival data on adjuvant anti-PD-1 therapy for patients with newly diagnosed and recurrent stage III melanoma

We aimed to compare the relapse-free survival (RFS) in patients treated with adjuvant anti-programmed cell death-1 (anti-PD-1) therapy for a first diagnosis of stage III melanoma to patients treated after resection of the recurrences. Patients treated with adjuvant anti-PD-1 therapy after complete resection of stage III melanoma between September 2018 and January 2021, were included. Depending on when adjuvant anti-PD-1 treatment was initiated, patients were divided over 2 cohorts: for the first diagnosis (cohort A) or for a second or subsequent diagnosis (cohort B) of stage III melanoma. Clinical data and RFS were compared between cohorts. 66 patients were included: 37 in cohort A, 29 in cohort B. Median follow-up time from the start of adjuvant therapy was 21 months and 17 months in cohorts A and B, respectively. Significant differences in ulceration of the primary tumor ( P  = 0.032), stage according to the 7th AJCC (American Joint Committee on Cancer , P  = 0.026) and type of metastatic involvement ( P  = 0.005) were found between cohorts. In cohorts A and B, 18 (49%) and 8 (28%) patients developed a recurrence and the 1-year RFS was 51% and 72%, respectively. In cohort B, RFS remained longer in the patients of which the interval between first diagnosis of stage III melanoma and start of adjuvant therapy was >48 months compared to ≤48 months (83% vs. 65%, P  = 0.253). This study demonstrates that patients with recurrent stage III disease, not previously treated with adjuvant systemic therapy, may derive similar benefit to a first diagnosis of stage III patients if access to adjuvant therapy changes.

Avelumab treatment for patients with metastatic Merkel cell carcinoma can be safely stopped after 1 year and a PET/CT-confirmed complete response

BACKGROUND

Immune checkpoint inhibitor treatment of patients with metastatic Merkel cell carcinoma (mMCC) has shown high response rates, ranging from 33% to 73%. The ideal duration of treatment, however, is currently unknown. The aim of this study was to evaluate if avelumab treatment for mMCC can be safely stopped after 1 year of treatment and a complete response (CR) confirmed by fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) imaging.

METHODS

Patients who received more than one dose of avelumab treatment for mMCC between November 2017 and February 2022 were included in this study. Treatment was discontinued in case of a FDG-PET/CT confirmed CR after 1 year (26 cycles) of avelumab or a CR and unacceptable toxicity earlier. The primary end point was recurrence-free survival (RFS).

RESULTS

Sixty-five patients were included: 25 (38%) had a FDG-PET/CT-confirmed CR at discontinuation of avelumab. In those 25 patients, reasons for discontinuation of treatment were completion of 1 year of treatment in 13 (52%), toxicity in five (20%), and patient preference in seven (28%). Median duration of treatment in this group was 11 months (interquartile range, 6.1-11.7). Median follow-up was 27 months (interquartile range, 15.8-33.8). The 12-month RFS was 88% (95% CI, 0.74-1) and median RFS was not reached. Two patients (8%) had a recurrence at 4 and 7 months after discontinuation of treatment.

CONCLUSIONS

Patients with mMCC who acquire a CR on PET/CT imaging appear to have durable responses after discontinuation of treatment after 1 year.

Oncological Outcome After Lymph Node Dissection for Cutaneous Squamous Cell Carcinoma

BACKGROUND

Although cutaneous squamous cell carcinoma (cSCC) is common, lymph node metastases are relatively rare and are usually treated with lymph node dissection (LND). The aim of this study was to describe the clinical course and prognosis after LND for cSCC at all anatomical locations.

METHODS

A retrospective search at three centres was performed to identify patients with lymph node metastases of cSCC who were treated with LND. Prognostic factors were identified by uni- and multivariable analysis.

RESULTS

A total of 268 patients were identified with a median age of 74. All lymph node metastases were treated with LND, and 65% of the patients received adjuvant radiotherapy. After LND, 35% developed recurrent disease both locoregionally and distantly. Patients with more than one positive lymph node had an increased risk for recurrent disease. 165 (62%) patients died during follow-up of whom 77 (29%) due to cSCC. The 5-year OS- and DSS rate were 36% and 52%, respectively. Disease-specific survival was significantly worse in immunosuppressed patients, patients with primary tumors >2cm and patients with more than one positive lymph node.

CONCLUSIONS

This study shows that LND for patients with lymph node metastases of cSCC leads to a 5-year DSS of 52%. After LND, approximately one-third of the patients develop recurrent disease (locoregional and/or distant), which underscores the need for better systemic treatment options for locally advanced cSCC. The size of the primary tumor, more than one positive lymph node, and immunosuppression are independent predictors for risk of recurrence and disease-specific survival after LND for cSCC.

Prognostic and predictive value of metformin in the European Organisation for Research and Treatment of Cancer 1325/KEYNOTE-054 phase III trial of pembrolizumab versus placebo in resected high-risk stage III melanoma

BACKGROUND

Metformin is a commonly prescribed and well-tolerated medication. In laboratory studies, metformin suppresses BRAF wild-type melanoma cells but accelerates the growth of BRAF-mutated cells. This study investigated the prognostic and predictive value of metformin, including with respect to BRAF mutation status, in the European Organisation for Research and Treatment of Cancer 1325/KEYNOTE-054 randomised controlled trial.

METHODS

Patients with resected high-risk stage IIIA, IIIB, or IIIC melanoma received 200 mg of pembrolizumab (n = 514) or placebo (n = 505) every 3 weeks for twelve months. Pembrolizumab prolonged recurrence-free survival (RFS) and distant metastasis-free survival (DMFS) at approximately 42 months median follow-up (Eggermont et al., TLO, 2021). Multivariable Cox regression was used to estimate associations of metformin with RFS and DMFS. Interaction terms were used to model effect modification by treatment and BRAF mutation.

RESULTS

Fifty-four patients (0.5%) used metformin at baseline. Metformin was not significantly associated with RFS (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.52-1.45) and DMFS (HR 0.82, 95% CI 0.47-1.44). The interaction between metformin and the treatment arm was not significant for either RFS (p = 0.92) or DMFS (p = 0.93). Among patients with mutated BRAF, the association of metformin with RFS (HR 0.70, 95% CI 0.37-1.33) was greater in magnitude though not significantly different to those without mutated BRAF (HR 0.98, 95% CI 0.56-1.69).

CONCLUSIONS

There was no significant impact of metformin use on pembrolizumab efficacy in resected high-risk stage III melanoma. However, larger studies or pooled analyses are needed, particularly to explore a possible effect of metformin in BRAF-mutated melanoma.

Adjuvant therapy for stage II melanoma: the need for further studies

Immunotherapy with checkpoint inhibitors has revolutionised the outcomes for melanoma patients. In the metastatic setting, patients treated with nivolumab and ipilimumab have an expected 5-year survival of> 50%. For patients with resected high-risk stage III disease, adjuvant pembrolizumab, nivolumab or dabrafenib and trametinib are associated with a significant improvement in both relapse-free survival (RFS) and distant metastasis-free survival (DMFS). More recently neoadjuvant immunotherapy has shown very promising outcomes in patients with clinically detectable nodal disease and is likely to become a new standard of care. For stage IIB/C disease, two pivotal adjuvant trials of pembrolizumab and nivolumab have also reported a significant improvement in both RFS and DMFS. However, the absolute benefit is low and there are concerns about the risk of severe toxicities as well as long-term morbidity from endocrine toxicity. Ongoing registration phase III trials are currently evaluating newer immunotherapy combinations and the role of BRAF/MEK-directed targeted therapy for stage II melanoma. However, our ability to personalise therapy based on molecular risk stratification has lagged behind the development of novel immune therapies. There is a critical need to evaluate the use of tissue and blood-based biomarkers, to better select patients that will recur and avoid unnecessary treatment for the majority of patients cured by surgery alone.

IFN-γ signature enables selection of neoadjuvant treatment in patients with stage III melanoma

Neoadjuvant ipilimumab + nivolumab has demonstrated high pathologic response rates in stage III melanoma. Patients with low intra-tumoral interferon-γ (IFN-γ) signatures are less likely to benefit. We show that domatinostat (a class I histone deacetylase inhibitor) addition to anti-PD-1 + anti-CTLA-4 increased the IFN-γ response and reduced tumor growth in our murine melanoma model, rationalizing evaluation in patients. To stratify patients into IFN-γ high and low cohorts, we developed a baseline IFN-γ signature expression algorithm, which was prospectively tested in the DONIMI trial. Patients with stage III melanoma and high intra-tumoral IFN-γ scores were randomized to neoadjuvant nivolumab or nivolumab + domatinostat, while patients with low IFN-γ scores received nivolumab + domatinostat or ipilimumab + nivolumab + domatinostat. Domatinostat addition to neoadjuvant nivolumab ± ipilimumab did not delay surgery but induced unexpected severe skin toxicity, hampering domatinostat dose escalation. At studied dose levels, domatinostat addition did not increase treatment efficacy. The baseline IFN-γ score adequately differentiated patients who were likely to benefit from nivolumab alone versus patients who require other therapies.

Baseline ultrasound and FDG-PET/CT imaging in Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a cutaneous tumor with a high tendency to metastasize, and a significant proportion of patients have metastases at first presentation. This study aims to determine the value of baseline ultrasound (US) and ¹⁸ fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸ FDG-PET/CT) imaging in both patients with clinically localized MCC (Stage I/II) and patients who present with palpable lymph nodes (Stage III).

METHODS

This retrospective cohort included 135 MCC patients who underwent baseline US (with fine needle aspiration cytology (FNAC)) and/or FDG-PET/CT imaging between 2015 and 2021.

RESULTS

Of the 104 patients with clinically localized disease, 48% were upstaged to Stage III and 3% to Stage IV by imaging or sentinel lymph node biopsy (SLNB). FDG-PET/CT imaging identified regional metastases in 23%, while US with FNAC identified regional metastases in 19%. SLNB was performed in 56 patients, of whom 57% were upstaged to Stage III. Of the 31 patients who presented with palpable lymph nodes, 16% were upstaged to Stage IV by FDG-PET/CT imaging.

CONCLUSION

Baseline imaging frequently upstages Stage I/II MCC patients to Stage III, both by US and FDG-PET/CT, Stage IV disease is rarely identified. Patients who present with palpable nodes are frequently upstaged to Stage IV by FDG-PET/CT imaging.

Alternatives and reduced need for sentinel lymph node biopsy (SLNB) staging for melanoma

Sentinel lymph node biopsy (SLNB) has been introduced in the 1990s to identify patients who might benefit from completion lymph node dissection. Neither SLNB nor CLND improved survival, but SLNB staging did provide the best staging, above Breslow thickness and ulceration. The SLN status and SLN tumour burden were used in all trials until date looking at modern adjuvant systemic therapy with immune checkpoint inhibition (ICI) or targeted therapies (TT). Adjuvant ICI and TT are shifting towards stage II melanoma. The question is whether there is still role for SLNB in melanoma, in this day and age, and if so, how does the future look for SLNB staging? The SLN status and SLN tumour burden might be useful for a consultation to discuss the number needed to treat in a risk/benefit discussion. For stage IIB/C patients, it seems likely, however, that patients will forego a nuclear scan followed by the risk of surgical intervention and morbidity associated with SLNB if they opt to receive adjuvant therapy regardless of the SLNB result. For stage I/IIA, it is still required to detect high-risk patients who might benefit from adjuvant therapy. However, biomarkers are emerging, such as gene expression profilers (GEP), immunohistological signatures and liquid biopsies with ctDNA. There still is a role for SLNB staging in melanoma today, but we expect that the availability of therapeutic option independent of SLNB status as well as emergence of validated biomarkers to predict risk will reduce the need for SLNB staging in the upcoming decade to the point it will no longer be used.

Surgical outcomes of lymph node dissections for stage III melanoma after neoadjuvant systemic therapy are not inferior to upfront surgery

BACKGROUND

Neoadjuvant systemic therapy has shown promising results in the treatment of high-risk stage III melanoma; however, the effects on surgery are currently unknown. This study aims to compare the surgical outcomes, in terms of postoperative complications, postoperative morbidity, duration of surgery and textbook outcomes, of patients with high-risk stage III melanoma who received neoadjuvant systemic therapy followed by lymph node dissection with patients who received an upfront lymph node dissection.

METHODS

In this retrospective cohort study, patients with high-risk stage III melanoma treated with neoadjuvant anti-PD1 and anti-CTLA4 in the OpACIN (NCT02437279) and OpACIN-neo (NCT02977052) trial between October 2014 and August 2018 were included and compared to patients who received upfront surgery in the same time period.

RESULTS

A total of 120 patients were included in this study, of whom 44 received neoadjuvant systemic therapy and 76 underwent upfront surgery. There was no significant difference in the overall rate of postoperative complications between the neoadjuvant group and the upfront surgery group (31.8% versus 36.8%, p = 0.578) and neither in rate of postoperative morbidity (seroma 56.8% versus 57.9%, p = 0.908) (lymphedema 22.7% versus 13.2%, p = 0.175). There was a non-significant difference towards a slightly longer duration of surgery after neoadjuvant immunotherapy (105 versus 90 min, p = 0.077). There were no differences in textbook outcomes (50% versus 49%, p = 0.889).

CONCLUSION

This study shows that the surgical outcomes for patients who underwent a lymph node dissection after neoadjuvant systemic immunotherapy or underwent upfront lymph node dissection for high-risk stage III melanoma are comparable.

Common toxicities associated with immune checkpoint inhibitors and targeted therapy in the treatment of melanoma: A systematic scoping review

INTRODUCTION

This systematic scoping review compares the toxicities experienced by patients receiving immune checkpoint inhibitors (ICIs) or targeted therapy (TT) for stage III (resected and unresectable) and stage IV melanoma.

METHODS

OVID Medline, Embase, and PsycInfo were searched to identify Phase III trials reporting toxicities of FDA-approved ICIs and TT for advanced melanoma. AEs that were reported by ≥ 10% of patients in the evaluated trials were included.

RESULTS

Toxicity profiles of 11208 patients from 24 studies were reviewed. The rate of AEs was lower with ICIs compared to TT. However, ICIs were associated with higher rates of long-term or permanent AEs compared to TT, where toxicities generally were shortterm and reversible with treatment discontinuation.

CONCLUSION

The toxicity profiles of ICIs and TT vary substantially. Whilst the rate of AEs was lower with ICIs than during TT, it was also associated with higher rates of potentially chronic AEs.

Neo-adjuvant immunotherapy emerges as best medical practice, and will be the new standard of care for macroscopic stage III melanoma

Survival of macroscopic stage III melanoma is poor. Five-year overall survival and relapse-free survival rates for surgery alone range from 40 to 59% and 30 to-39%, respectively. The current standard of care is therapeutic lymph node dissection (TLND) followed by a year of adjuvant systemic therapy. Multiple phase 2 trials have shown that neo-adjuvant immunotherapy induces major pathologic response (MPR) rates (pathologic complete response (pCR): pCR, 0% viable tumour cells; near-pCR, <10% viable tumour cells), which translate into durable relapse free survival rates. Single agent anti-PD-1 achieves 20-30% MPR, the combination of ipilimumab and nivolumab doubles the MPR rates to 50-60%. The OpACIN trial demonstrated that neoadjuvant immunotherapy induced both higher numbers and a broader repertoire of tumour-resident T-cells in peripheral blood compared with adjuvant immunotherapy. Very recently, the randomised phase 2 trial S1801 reported its first interim results. S1801 compared TLND, followed by 18 courses of adjuvant pembrolizumab, to three courses of neoadjuvant pembrolizumab, followed by surgery and 15 adjuvant doses. With a median follow-up of 14 months, a 23% EFS rate benefit was observed. The ongoing phase 3 NADINA trial randomises patients between TLND + one year of adjuvant nivolumab (control arm) or 2 courses of neoadjuvant therapy with ipilimumab + nivolumab, followed by adjuvant therapy only for non-MPR patients. There is rapid, consistent, and accumulating evidence generated from all phase 1 and phase 2 trials, indicating clinical superiority of neoadjuvant immunotherapy over adjuvant systemic therapy for macroscopic stage III melanoma. Therefore, payers should consider neoadjuvant immunotherapy for reimbursement as this approach is the best option for our patients, and classify it as the best medical practice.

Talimogene laherparepvec monotherapy for head and neck melanoma patients

Talimogene laherparepvec (T-VEC) is a modified herpes simplex virus, type 1, intralesionally administered in patients with stage IIIB/C-IVM1a unresectable melanoma. When surgery is not a treatment option in the head and neck region, T-VEC can be an elegant alternative to systemic immunotherapy. Ten patients with metastatic melanoma in the head and neck region started treatment with T-VEC monotherapy at the Netherlands Cancer Institute. We collected data on response, adverse events (AEs), and baseline characteristics. For response evaluation, we used clinical evaluation with photography, 3-monthly PET/computed tomography (PET/CT) using 18F-fluoro-2-D-deoxyglucose, and histological biopsies. Median age at baseline was 78.2 (35-97) years with a median follow-up of 11.6months. Of these 10 patients, 5 had a complete response (CR), 3 had a partial response, 1 had stable disease and 1 showed progressive disease (PD) as their best response. Best overall response rate (ORR) was 80%. Median progression-free survival was 10.8 months (95% confidence interval, 2.2-19.4). Grade 1 AEs occurred in all patients. Mostly, these consisted of fatigue, influenza-like symptoms, and injection site pain. PET-CT and histological biopsies proved to be clinically useful tools to evaluate treatment response for T-VEC monotherapy, confirming pCR or PD to stage IV disease requiring systemic treatment. ORR for T-VEC monotherapy for melanoma in the head and neck region at our institute was 80% with 50% achieving a CR. This realworld data demonstrates promising results and suggests T-VEC can be an alternative to systemic therapy in this select, mostly elderly patient population.

Is a History of Optimal Staging by Sentinel Lymph Node Biopsy in the Era Prior to Adjuvant Therapy Associated with Improved Outcome Once Melanoma Patients have Progressed to Advanced Disease?

INTRODUCTION

Sentinel lymph node biopsy (SLNB) is important for staging in patients with primary cutaneous melanoma. Did having previously undergone SLNB also affect outcomes in patients once they have progressed to metastatic melanoma in the era prior to adjuvant therapy?

METHODS

Data were retrieved from the Dutch Melanoma Treatment Registry, a prospectively collected, nationwide database of patients with unresectable stage IIIC or IV (advanced) melanoma between 2012 and 2018. Melanoma-specific survival (MSS) was compared between patients with advanced cutaneous melanoma, previously treated with a wide local excision (WLE) or WLE combined with SLNB as initial treatment of their primary tumor. Cox regression analyses were used to analyze the influence of different variables on MSS.

RESULTS

In total, 2581 patients were included, of whom 1412 were treated with a WLE of the primary tumor alone and 1169 in whom this was combined with SLNB. At a median follow-up of 44 months from diagnosis of advanced melanoma, MSS was significantly longer in patients who had previously undergone SLNB {median 23 months (95% confidence interval [CI] 19-29) vs. 18 months (95% CI 15-20) for patients treated with WLE alone; p = 0.002}. However, multivariate Cox regression did not identify SLNB as an independent favorable prognostic factor for MSS after diagnosis of advanced melanoma.

CONCLUSION

Prior to the availability of adjuvant systemic therapy, once patients have unresectable stage IIIC or IV (advanced) melanoma, there was no difference in disease outcome for patients who were or were not previously staged with SLNB.

The end of wide local excision (WLE) margins for melanoma ?

CLINICAL QUESTION

Is there nowadays any benefit of continuing the practice of routine wide local excision (WLE) for primary stage I/II cutaneous melanoma?

BACKGROUND

WLE aims to eradicate potential microsatellites around melanomas and thereby reduce local recurrence rates and improve overall survival. Six large prospective randomised trials investigated WLE versus wider WLE, they all failed to show any effect on overall survival (OS).

METHODS

A literature search was performed to identify data on outcome after omitting WLE. Additionally circumstantial evidence was gathered from pathology studies and outcomes of modified surgical techniques, as well as publications on morbidity.

RESULTS

No prospective and one retrospective study was found. The retrospective study showed no difference in OS after correction for confounding factors. Pathology studies showed a low incidence of residual melanoma in WLE specimen (0-4.2%). Mohs surgery does not show a difference in recurrence rates or OS. WLE is associated with considerable postoperative morbidity, which increases with wider excision margins.

CONCLUSION

There is no solid prospective evidence to support the classic dogma of a 2-step approach with the use of WLE for primary cutaneous melanoma that has been completely excised on diagnostic excision biopsy. We recommend to setup and conduct a prospective randomised trial to compare the classical 2-step approach with WLE to a complete diagnostic excision only to abolish the routine practice of WLE in the future.

Tumor-Infiltrating Lymphocyte Therapy or Ipilimumab in Advanced Melanoma

BACKGROUND

Immune checkpoint inhibitors and targeted therapies have dramatically improved outcomes in patients with advanced melanoma, but approximately half these patients will not have a durable benefit. Phase 1-2 trials of adoptive cell therapy with tumor-infiltrating lymphocytes (TILs) have shown promising responses, but data from phase 3 trials are lacking to determine the role of TILs in treating advanced melanoma.

METHODS

In this phase 3, multicenter, open-label trial, we randomly assigned patients with unresectable stage IIIC or IV melanoma in a 1:1 ratio to receive TIL or anti-cytotoxic T-lymphocyte antigen 4 therapy (ipilimumab at 3 mg per kilogram of body weight). Infusion of at least 5×10⁹ TILs was preceded by nonmyeloablative, lymphodepleting chemotherapy (cyclophosphamide plus fludarabine) and followed by high-dose interleukin-2. The primary end point was progression-free survival.

RESULTS

A total of 168 patients (86% with disease refractory to anti-programmed death 1 treatment) were assigned to receive TILs (84 patients) or ipilimumab (84 patients). In the intention-to-treat population, median progression-free survival was 7.2 months (95% confidence interval [CI], 4.2 to 13.1) in the TIL group and 3.1 months (95% CI, 3.0 to 4.3) in the ipilimumab group (hazard ratio for progression or death, 0.50; 95% CI, 0.35 to 0.72; P<0.001); 49% (95% CI, 38 to 60) and 21% (95% CI, 13 to 32) of the patients, respectively, had an objective response. Median overall survival was 25.8 months (95% CI, 18.2 to not reached) in the TIL group and 18.9 months (95% CI, 13.8 to 32.6) in the ipilimumab group. Treatment-related adverse events of grade 3 or higher occurred in all patients who received TILs and in 57% of those who received ipilimumab; in the TIL group, these events were mainly chemotherapy-related myelosuppression.

CONCLUSIONS

In patients with advanced melanoma, progression-free survival was significantly longer among those who received TIL therapy than among those who received ipilimumab. (Funded by the Dutch Cancer Society and others; ClinicalTrials.gov number, NCT02278887.).

Five-Year Analysis of Adjuvant Pembrolizumab or Placebo in Stage III Melanoma

Pembrolizumab or Placebo in Stage III MelanomaPatients with stage III melanoma randomly received adjuvant pembrolizumab or placebo. Five-year recurrence-free survival was 55.4% (95% CI, 50.8 to 59.8) versus 38.3% (33.9 to 42.7) and 5-year metastasis-free survival was 60.6% (56.0 to 64.9) versus 44.5% (39.9 to 48.9) for adjuvant pembrolizumab and placebo, respectively. No new safety signals were associated with adjuvant pembrolizumab.

Neoadjuvant nivolumab + T-VEC combination therapy for resectable early stage or metastatic (IIIB-IVM1a) melanoma with injectable disease: study protocol of the NIVEC trial

Background

Trials investigating neoadjuvant treatment with immune checkpoint inhibitors (ICI) in patients with melanoma have shown high clinical and pathologic response rates. Treatment with talimogene laherparepvec (T-VEC), a modified herpes simplex virus type-1 (HSV-1), is approved for patients with unresectable stage IIIB-IVM1a melanoma and has the potential to make tumors more susceptible for ICI. Combination ICI and intralesional T-VEC has already been investigated in patients with unresectable stage IIIB-IV disease, however, no data is available yet on the potential benefit of this combination therapy in neoadjuvant setting.

Methods

This single center, single arm, phase II study aims to show an improved major pathologic complete response (pCR) rate, either pCR or near-pCR, up to 45% in 24 patients with resectable stage IIIB-IVM1a melanoma upon neoadjuvant combination treatment with intralesional T-VEC and systemic nivolumab (anti-PD-1 antibody). Patients will receive four courses of T-VEC up to 4 mL (first dose as seroconversion dose) and three doses of nivolumab (240 mg flatdose) every 2 weeks, followed by surgical resection in week nine. The primary endpoint of this trial is pathologic response rate. Secondary endpoints are safety, the rate of delay of surgery and event-free survival. Additionally, prognostic and predictive biomarker research and health-related quality of life evaluation will be performed.

Discussion

Intralesional T-VEC has the capacity to heighten the immune response and to elicit an abscopal effect in melanoma in combination with ICI. However, the potential clinical benefit of T-VEC plus ICI in the neoadjuvant setting remains unknown. This is the first trial investigating the efficacy and safety of neoadjuvant treatment of T-VEC and nivolumab followed by surgical resection in patients with stage IIIB-IVM1a melanoma, with the potential of high pathologic response rates and acceptable toxicity.

Trial registration

This trial was registered in the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT- number: 2019–001911-22) and the Central Committee on Research Involving Human Subjects (NL71866.000.19) on 4th June 2020.

Secondary identifying number: NCT04330430.

Single agent Talimogene Laherparepvec for stage IIIB-IVM1c melanoma patients: A systematic review and meta-analysis

Single-agent Talimogene Laherparepvec (T-VEC) was developed for treatment of unresectable and injectable stage III-IV melanoma. Since its approval and reimbursement, studies have reported varying response rates. The purpose of this systematic review and meta-analysis was to investigate the efficacy and safety of T-VEC. Of 341 publications that were identified, eight studies with a total of 642 patients were included. In patients with stage IIIB-IVM1a, the pooled complete- and overall response rate (CRR and ORR) were 41% and 64%, respectively. In patients with stage IIIB-IVM1c, the pooled CRR and ORR were 30% and 44%, respectively. In patients with stage IVM1b and IVM1c, the pooled CRR and ORR were 4% and 9%, respectively. Adverse events (AEs) were seen in 41-100% of all patients and 0-11% of AEs were severe. In conclusion, single agent T-VEC achieves the highest response rates in patients with early metastatic melanoma and is well-tolerated with generally only mild toxicities.

Re-introduction of T-VEC Monotherapy in Recurrent Melanoma is Effective

Talimogene laherparepvec (T-VEC) is a modified herpes simplex virus type 1, which can be administered intralesionally in patients with stage IIIB/C-IVM1a (American Joint Committee of Cancer; AJCC 7th edition) unresectable melanoma. In the case of disease recurrence, T-VEC can be re-introduced for the same category of patients. Five patients with recurrent disease after a prior achieved complete response (CR) recommenced treatment with T-VEC monotherapy at the Netherlands Cancer Institute. We collected data on response, adverse events and baseline characteristics. All 5 patients that were re-treated with T-VEC presented with in-transit metastases on the lower limb. Median age at baseline was 72.1 years with a median follow-up time of 30.4 months. Histologically proven CR was achieved after a median of 8 T-VEC courses on the initial exposure. Duration of response (time between first CR and recurrence) varied between 3.8 and 14.2 months. All 5 patients achieved a histologically and/or positron emission tomography/computed tomography proven CR again after re-introduction of T-VEC with a median of 5 courses. One patient (20%) developed a second recurrence and is currently still on treatment with T-VEC. No patients developed distant metastases. Grade 1 adverse events occurred in all patients. Mostly, these consisted of fatigue, influenza-like symptoms and injection site pain. Response to re-introduction of T-VEC monotherapy in this select patient population is promising. This real world data on re-introduction of T-VEC monotherapy in stage IIIB/C-IVM1a melanoma suggests T-VEC could be a treatment option for chronic disease control.

18F-FDG PET/CT During Neoadjuvant Targeted Therapy in Prior Unresectable Stage III Melanoma Patients: Can (Early) Metabolic Imaging Predict Histopathologic Response or Recurrence?

PURPOSE

The aim of this study was to investigate whether 18F-FDG PET/CT can predict histopathological response or recurrence in BRAF-mutated unresectable locally advanced stage III melanoma treated with neoadjuvant BRAF/MEK inhibition followed by resection and the value of PET in detecting early recurrence after resection.

PATIENTS AND METHODS

Twenty BRAF-mutated, unresectable stage III melanoma patients received BRAF/MEK inhibitors before surgery. 18F-FDG PET/CT was performed at baseline and 2 and 8 weeks after initiation of therapy. After resection, PET/CT was performed at specific time points during 5 years of follow-up. Pathological response was assessed on the dissection specimen. Response monitoring was measured with SUVmax, SUVpeak, MATV, and TLG and according to EORTC and PERCIST criteria.

RESULTS

Pathological response was assessed in 18 patients. Nine patients (50%) had a pathologic complete or near-complete response, and 9 (50%) had a pathologic partial or no response. EORTC or PERCIST response measurements did not correspond with pathologic outcome. SUVmax, SUVpeak, MATV, and TLG at all time points and absolute or percentage change among the 3 initial time points did not differ between the groups.During follow-up, 8 of 17 patients with R0 resection developed a recurrence, 6 recurrences were detected with imaging only, 4 of which with PET/CT in less than 6 months after surgery. PET parameters before surgery did not predict recurrence.

CONCLUSIONS

Baseline 18F-FDG PET or PET response in previous unresectable stage III melanoma patients seems not useful to predict pathologic response after neoadjuvant BRAF/MEK inhibitors treatment. However, PET/CT seems valuable in detecting recurrence early after R0 resection.

Predictors of Sentinel Lymph Node Metastasis in Patients with Thin Melanoma: An International Multi-institutional Collaboration

BACKGROUND

Consideration of sentinel lymph node biopsy (SLNB) is recommended for patients with T1b melanomas and T1a melanomas with high-risk features; however, the proportion of patients with actionable results is low. We aimed to identify factors predicting SLNB positivity in T1 melanomas by examining a multi-institutional international population.

METHODS

Data were extracted on patients with T1 cutaneous melanoma who underwent SLNB between 2005 and 2018 at five tertiary centers in Europe and Canada. Univariable and multivariable logistic regression analyses were performed to identify predictors of SLNB positivity.

RESULTS

Overall, 676 patients were analyzed. Most patients had one or more high-risk features: Breslow thickness 0.8-1 mm in 78.1% of patients, ulceration in 8.3%, mitotic rate > 1/mm² in 42.5%, Clark's level ≥ 4 in 34.3%, lymphovascular invasion in 1.4%, nodular histology in 2.9%, and absence of tumor-infiltrating lymphocytes in 14.4%. Fifty-three patients (7.8%) had a positive SLNB. Breslow thickness and mitotic rate independently predicted SLNB positivity. The odds of positive SLNB increased by 50% for each 0.1 mm increase in thickness past 0.7 mm (95% confidence interval [CI] 1.05-2.13) and by 22% for each mitosis per mm² (95% CI 1.06-1.41). Patients who had one excised node (vs. two or more) were three times less likely to have a positive SLNB (3.6% vs. 9.6%; odds ratio 2.9 [1.3-7.7]).

CONCLUSIONS

Our international multi-institutional data confirm that Breslow thickness and mitotic rate independently predict SLNB positivity in patients with T1 melanoma. Even within this highly selected population, the number needed to diagnose is 13:1 (7.8%), indicating that more work is required to identify additional predictors of sentinel node positivity.

Neoadjuvant Systemic Therapy (NAST) in Patients with Melanoma: Surgical Considerations by the International Neoadjuvant Melanoma Consortium (INMC)

Exciting advances in melanoma systemic therapies have presented the opportunity for surgical oncologists and their multidisciplinary colleagues to test the neoadjuvant systemic treatment approach in high-risk, resectable metastatic melanomas. Here we describe the state of the science of neoadjuvant systemic therapy (NAST) for melanoma, focusing on the surgical aspects and the key role of the surgical oncologist in this treatment paradigm. This paper summarizes the past decade of developments in melanoma treatment and the current evidence for NAST in stage III melanoma specifically. Issues of surgical relevance are discussed, including the risk of progression on NAST prior to surgery. Technical aspects, such as the definition of resectability for melanoma and the extent and scope of routine surgery are presented. Other important issues, such as the utility of radiographic response evaluation and method of pathologic response evaluation, are addressed. Surgical complications and perioperative management of NAST related adverse events are considered. The International Neoadjuvant Melanoma Consortium has the goal of harmonizing NAST trials in melanoma to facilitate rapid advances with new approaches, and facilitating the comparison of results across trials evaluating different treatment regimens. Our ultimate goals are to provide definitive proof of the safety and efficacy of NAST in melanoma, sufficient for NAST to become an acceptable standard of care, and to leverage this platform to allow more personalized, biomarker-driven, tailored approaches to subsequent treatment and surveillance.

Personalized response-directed surgery and adjuvant therapy after neoadjuvant ipilimumab and nivolumab in high-risk stage III melanoma: the PRADO trial

Neoadjuvant ipilimumab and nivolumab induces high pathologic response rates (pRRs) in clinical stage III nodal melanoma, and pathologic response is strongly associated with prolonged relapse-free survival (RFS). The PRADO extension cohort of the OpACIN-neo trial ( NCT02977052 ) addressed the feasibility and effect on clinical outcome of using pathologic response after neoadjuvant ipilimumab and nivolumab as a criterion for further treatment personalization. In total, 99 patients with clinical stage IIIb-d nodal melanoma were included and treated with 6 weeks of neoadjuvant ipilimumab 1 mg kg-1 and nivolumab 3 mg kg-1. In patients achieving major pathologic response (MPR, ≤10% viable tumor) in their index lymph node (ILN, the largest lymph node metastasis at baseline), therapeutic lymph node dissection (TLND) and adjuvant therapy were omitted. Patients with pathologic partial response (pPR; >10 to ≤50% viable tumor) underwent TLND only, whereas patients with pathologic non-response (pNR; >50% viable tumor) underwent TLND and adjuvant systemic therapy ± synchronous radiotherapy. Primary objectives were confirmation of pRR (ILN, at week 6) of the winner neoadjuvant combination scheme identified in OpACIN-neo; to investigate whether TLND can be safely omitted in patients achieving MPR; and to investigate whether RFS at 24 months can be improved for patients achieving pNR. ILN resection and ILN-response-tailored treatment were feasible. The pRR was 72%, including 61% MPR. Grade 3-4 toxicity within the first 12 weeks was observed in 22 (22%) patients. TLND was omitted in 59 of 60 patients with MPR, resulting in significantly lower surgical morbidity and better quality of life. The 24-month relapse-free survival and distant metastasis-free survival rates were 93% and 98% in patients with MPR, 64% and 64% in patients with pPR, and 71% and 76% in patients with pNR, respectively. These findings provide a strong rationale for randomized clinical trials testing response-directed treatment personalization after neoadjuvant ipilimumab and nivolumab.

Neoadjuvant Immune Checkpoint Inhibitor Therapy in Melanoma: Efficacy, Safety and Timing

The introduction of effective systemic therapies has significantly changed the treatment of stage III and IV melanoma. Both immune checkpoint inhibitors and targeted therapies have improved recurrence-free survival in the adjuvant setting. Recent interest has sparked for neoadjuvant systemic therapy with immune checkpoint inhibitors. The intended benefit of pre-operative treatment with immunotherapy is amongst others to enable tailoring of the surgery and adjuvant systemic therapy according to the treatment response. Most importantly, recurrence-free survival might be improved by neoadjuvant systemic therapy over the current standard of care of surgery followed by adjuvant systemic therapy. The first phase I and II trials investigating anti-PD1 inhibitors, both as a single agent and in combination with anti-CTLA-4 inhibitors or other therapeutic agents, have shown promising results. Pathological complete response on neoadjuvant systemic therapy seems a valid surrogate endpoint for relapse-free and overall survival. Pathological complete response rates in these trials vary between 30 and 70%. The optimal dose with respect to efficacy and toxicity and the interval between systemic and surgical treatment remain important issues to address. Accumulating follow-up data and ongoing phase III studies must prove if neoadjuvant systemic therapy is superior to surgery followed by standard-of-care adjuvant therapy.

Merkel Cell Carcinoma, the Impact of Clinical Excision Margins and Mohs Micrographic Surgery on Recurrence and Survival: A Systematic Review

BACKGROUND

When treating Merkel cell carcinoma (MCC), the relation between wide local excision (WLE) margin and recurrence or survival is unclear. Mohs micrographic surgery (MMS) is an alternative surgical option for MCC, but it is unknown whether the local recurrence rate differs between MMS and WLE.

OBJECTIVE

To systematically assess the available literature to determine the recurrence and survival rates when treating MCC with MMS and different clinical excision margins.

MATERIALS AND METHODS

The MEDLINE, EMBASE, and CENTRAL databases were searched. Two independent reviewers selected studies that defined clear excision margins and either recurrence or survival. When possible, individual cases were extracted from case series and included in the analyses. Other studies were reviewed narratively.

RESULTS

Overall, 1108 studies were identified; of which, 19 case series (168 cases) and 12 cohort studies were eligible. None of the cohort studies showed significant differences in recurrence or survival for either excision margins or MMS. Equally, logistic and Cox regression analyses of the case series revealed no significant differences in recurrence or survival between different excision margins and MMS.

CONCLUSION

Synthesis of the available data does not indicate differences in recurrence and/or survival rates for MCC between different clinical excision margins and MMS.

Representativeness of the Index Lymph Node for Total Nodal Basin in Pathologic Response Assessment After Neoadjuvant Checkpoint Inhibitor Therapy in Patients With Stage III Melanoma

IMPORTANCE

Neoadjuvant checkpoint inhibition in patients with high-risk stage III melanoma shows high pathologic response rates associated with a durable relapse-free survival. Whether a therapeutic lymph node dissection (TLND) can be safely omitted when a major pathologic response in the largest lymph node metastasis at baseline (index lymph node; ILN) is obtained is currently being investigated. A previous small pilot study (n = 12) showed that the response in the ILN may be representative of the pathologic response in the entire TLND specimen.

OBJECTIVE

To assess the concordance of response between the ILN and the total lymph node bed in a larger clinical trial population.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective pathologic response analysis of a multicenter clinical trial population of patients from the randomized Study to Identify the Optimal Adjuvant Combination Scheme of Ipilimumab and Nivolumab in Melanoma Patients (OpACIN) and Optimal Neo-Adjuvant Combination Scheme of Ipilimumab and Nivolumab (OpACIN-neo) trials. Included patients were treated with 6 weeks neoadjuvant ipilimumab plus nivolumab. Patient inclusion into the trials was conducted from August 12, 2015, to October 24, 2016 (OpACIN), and November 24, 2016, and June 28, 2018 (OpACIN-neo). Data were analyzed from April 1, 2020, to August 31, 2021.

MAIN OUTCOMES AND MEASURES

Concordance of the pathologic response between the ILN and the TLND tumor bed. The pathologic response of the ILN was retrospectively assessed according to the International Neoadjuvant Melanoma Consortium criteria and compared with the pathologic response of the entire TLND specimen.

RESULTS

A total of 82 patients treated with neoadjuvant ipilimumab and nivolumab followed by TLND (48 [59%] were male; median age, 58.5 [range, 18-80] years) were included. The pathologic response in the ILN was concordant with the entire TLND specimen response in 81 of 82 patients (99%) and in 79 of 82 patients (96%) concordant when comparing the ILN response with the response in every individual lymph node. In the single patient with a discordant response, the ILN response (20% viable tumor, partial pathologic response) underestimated the entire TLND specimen response (5% viable, near-complete pathologic response). Two other patients each had 1 small nonindex node that contained 80% viable tumor (pathologic nonresponse) whereas all other lymph nodes (including the ILN) showed a partial pathologic response. In these 2 patients, the risk of regional relapse might potentially have been increased if TLND had been omitted.

CONCLUSIONS AND RELEVANCE

The results of this study suggest that the pathologic response of the ILN may be considered a reliable indicator of the entire TLND specimen response and may support the ILN response-directed omission of TLND in a prospective trial.

Prognostic and predictive value of β-blockers in the EORTC 1325/KEYNOTE-054 phase III trial of pembrolizumab versus placebo in resected high-risk stage III melanoma

BACKGROUND

β-adrenergic receptors are upregulated in melanoma cells and contribute to an immunosuppressive, pro-tumorigenic microenvironment. This study investigated the prognostic and predictive value of β-adrenoreceptor blockade by β-blockers in the EORTC1325/KEYNOTE-054 randomised controlled trial.

METHODS

Patients with resected stage IIIA, IIIB or IIIC melanoma and regional lymphadenectomy received 200 mg of adjuvant pembrolizumab (n = 514) or placebo (n = 505) every three weeks for one year or until recurrence or unacceptable toxicity. At a median follow-up of 3 years, pembrolizumab prolonged recurrence-free survival (RFS) compared to placebo (hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.47-0.68). β-blocker use was defined as oral administration of any β-blocker within 30 days of randomisation. A multivariable Cox proportional hazard model was used to estimate the HR for the association between the use of β-blockers and RFS.

RESULTS

Ninety-nine (10%) of 1019 randomised patients used β-blockers at baseline. β-blockers had no independent prognostic effect on RFS: HR 0.96 (95% CI 0.70-1.31). The HRs of RFS associated with β-blocker use were 0.67 (95% CI 0.38-1.19) in the pembrolizumab arm and 1.15 (95% CI 0.80-1.66) in the placebo arm. The HR of RFS associated with pembrolizumab compared to placebo was 0.34 (95% CI 0.18-0.65) among β-blocker users and 0.59 (95% CI 0.48-0.71) among those not using β-blockers.

CONCLUSIONS

This study suggests no prognostic effect of β-blockers in resected high-risk stage III melanoma. However, β-blockers may predict improved efficacy of adjuvant pembrolizumab treatment. The combination of immunotherapy with β-blockers merits further investigation. This study is registered with ClinicalTrials.gov, NCT02362594, and EudraCT, 2014-004944-37.

False positive FDG uptake in melanoma patients treated with talimogene laherparepvec (T-VEC)

Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex virus-1-based oncolytic immunotherapy and has been approved for the local treatment of unresectable (stage IIIB/C and IVM1a) cutaneous melanoma. During T-VEC treatment, tumor response is often evaluated using [18F]2-fluoro-2-deoxy- d-glucose(FDG) positron emission tomography/computed tomography (PET/CT). In a Dutch cohort (n = 173), almost one-third of patients developed new-onset FDG uptake in uninjected locoregional lymph nodes during T-VEC. In 36 out of 53 (68%) patients with new nodal FDG uptake, nuclear medicine physicians classified this FDG uptake as "suspected metastases" without clinical or pathological confirmation in the majority of patients. These false positive results indicate that new-onset FDG uptake in locoregional lymph nodes during T-VEC treatment does not necessarily reflect progressive disease, but may be associated with immune infiltration. In current clinical practice, physicians should be aware of the high false positive rate of FDG uptake during treatment with T-VEC in patients with melanoma. Therefore, pathological examination of lymph node lesions with new FDG uptake is recommended to differentiate between progressive disease and immune infiltration after treatment with T-VEC.

Postoperative Radiotherapy in Stage I-III Merkel Cell Carcinoma

BACKGROUND

Postoperative radiotherapy (PORT) is currently recommended for the treatment of Merkel cell carcinoma. Nevertheless, deviations occur frequently due to the generally elderly and frail patient population. We aimed to evaluate the influence of PORT on survival in stage I-III MCC patients treated in the Netherlands.

METHODS

Patients were included retrospectively between 2013 and 2018. Fine-Gray method was used for cumulative incidence of recurrence and MCC-related survival, cox regression was performed for overall survival (OS). Analyses were performed in patients with clinical (sentinel node biopsy [SN] not performed) stage I/II (c-I/II-MCC), pathologic (SN negative) stage I/II (p-I/II-MCC) and stage III MCC (III-MCC), separately. Propensity score matching (PSM) was performed to assess confounding by indication.

RESULTS

In total 182 patients were included, 35 had p-I/II-MCC, 69 had c-I/II-MCC and 78 had III-MCC. Median follow up time was 53.5 (IQR 33.4-67.4), 30.5 (13.0-43.6) and 29.3 (19.3-51.0) months, respectively. Multivariable analysis showed PORT to be associated with less recurrences and improved OS, but not with MCC-related survival. In stage III-MCC, extracapsular extension (sub-distribution hazard [SDH] 4.09, p=0.012) and PORT (SDH 0.45, p=0.044) were associated with recurrence, and ≥4 positive lymph nodes (SDH 3.24, p=0.024) were associated with MCC-related survival.

CONCLUSIONS

PORT was associated with less recurrences and improved OS in patients with stage I-III MCC, but not with improved MCC-related survival. Trends in OS benefit are likely to be caused by selection bias suggesting further refinement of criteria for PORT is warranted, for instance by taking life expectancy into account.

External Validation of a Dutch Predictive Nomogram for Complete Response to T-VEC in an Independent American Patient Cohort

PURPOSE

Talimogene Laherparepvec (T-VEC) is a modified herpes simplex virus type-1 used as intralesional immunotherapy in stage IIIB-IVM1a melanoma patients. Recently, Stahlie et al. published a predictive model for complete response (CR) to T-VEC. This study was designed to validate this model externally in an independent, American patient cohort.

METHODS

In total, 71 stage IIIB-IVM1a melanoma patients treated with T-VEC at Moffitt Cancer Center were included. A second nomogram was built incorporating the same predictive factors: tumor size (diameter of largest metastasis), type of metastases (cutaneous, subcutaneous and nodal), and number of metastases (cutoff: < 20 and > 20). Predictive accuracy was assessed through calculation of overall performance, discriminative ability, and calibration.

RESULTS

The two cohorts were similar in many clinicopathologic factors and only differing in tumor mutational status and use of systemic therapy prior to T-VEC. In the validation cohort, 37 (52%) patients showed CR, 22 (31%) partial response (PR), 2 (5.6%) stable disease (SD), and 10 (15%) progressive disease (PD). Of those who demonstrated a CR, 16 (43%) recurred. Overall performance was good (0.164), and discriminative power resulted in fair discriminative ability (0.827). The calibration curve showed slight underestimation for predicted probabilities > 0.15 and slight overestimation <0.15.

CONCLUSIONS

The original model as well as the validation model show comparable and good predictive accuracy. The validation model reinforces the conclusion that for the best response to T-VEC, it should be used early on in the course of the disease, when the tumor burden is cutaneous with smaller diameter and fewer of metastases.

Talimogene Laherparepvec (T-VEC) for the Treatment of Advanced Locoregional Melanoma After Failure of Immunotherapy: An International Multi-Institutional Experience

BACKGROUND

Talimogene laherparepvec (T-VEC) is an oncolytic virus approved for the treatment of unresectable, recurrent melanoma. The role of T-VEC after progression on systemic immunotherapy (IO) remains undefined. The goal of this study was to characterize the efficacy of T-VEC after failure of IO in patients with unresectable metastatic melanoma.

METHODS

An international, multi-institutional review of AJCC version 8 stage IIIB-IV melanoma patients treated with T-VEC after failure of IO was performed at six centers from October 2015-December 2020. Primary outcome was in-field response; secondary outcomes included analyses of in-field and overall progression-free survival (PFS) and in-field and overall disease-free survival (DFS) after a complete response. Subset analysis of T-VEC initiation sequentially after or concurrently with IO was performed.

RESULTS

Of 112 patients, median age at T-VEC initiation was 69 years (range 21-93); 65 (58%) were male. Before T-VEC, 57% patients received one IO regimen, 42% received two or more, with most patients (n = 74, 66%) receiving T-VEC sequential to IO. Most were stage 3C (n = 51, 46%) at T-VEC initiation, 29 (26%) received injections to nodal disease. Over median follow-up of 14 months, in-field response at final T-VEC injection was 37% complete (CR), 14% partial (PR). T-VEC initiation sequentially or concurrently did not significantly affect in-field response (p = 0.26). Median in-field PFS was 15 months (95% confidence interval 4.6-NE). Median overall DFS after CR was 32 months (95% confidence interval 17-NE).

CONCLUSIONS

T-VEC after failure of IO is effective in unresectable, metastatic stage IIIB-IV melanoma. T-VEC initiation sequentially or concurrently did not significantly affect in-field response.