A prediction model for response to immune checkpoint inhibition in advanced melanoma

Predicting who will benefit from treatment with immune checkpoint inhibition (ICI) in patients with advanced melanoma is challenging. We developed a multivariable prediction model for response to ICI, using routinely available clinical data including primary melanoma characteristics. We used a population-based cohort of 3525 patients with advanced cutaneous melanoma treated with anti-PD-1-based therapy. Our prediction model for predicting response within 6 months after ICI initiation was internally validated with bootstrap resampling. Performance evaluation included calibration, discrimination and internal-external cross-validation. Included patients received anti-PD-1 monotherapy (n = 2366) or ipilimumab plus nivolumab (n = 1159) in any treatment line. The model included serum lactate dehydrogenase, World Health Organization performance score, type and line of ICI, disease stage and time to first distant recurrence-all at start of ICI-, and location and type of primary melanoma, the presence of satellites and/or in-transit metastases at primary diagnosis and sex. The over-optimism adjusted area under the receiver operating characteristic was 0.66 (95% CI: 0.64-0.66). The range of predicted response probabilities was 7%-81%. Based on these probabilities, patients were categorized into quartiles. Compared to the lowest response quartile, patients in the highest quartile had a significantly longer median progression-free survival (20.0 vs 2.8 months; P < .001) and median overall survival (62.0 vs 8.0 months; P < .001). Our prediction model, based on routinely available clinical variables and primary melanoma characteristics, predicts response to ICI in patients with advanced melanoma and discriminates well between treated patients with a very good and very poor prognosis.

BRAF/MEK inhibitor rechallenge in advanced melanoma patients

BACKGROUND

Effectivity of BRAF(/MEK) inhibitor rechallenge has been described in prior studies. However, structured data are largely lacking.

METHODS

Data from all advanced melanoma patients treated with BRAFi(/MEKi) rechallenge were retrieved from the Dutch Melanoma Treatment Registry. The authors analyzed objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) for both first treatment and rechallenge. They performed a multivariable logistic regression and a multivariable Cox proportional hazards model to assess factors associated with response and survival.

RESULTS

The authors included 468 patients in the largest cohort to date who underwent at least two treatment episodes of BRAFi(/MEKi). Following rechallenge, ORR was 43%, median PFS was 4.6 months (95% confidence interval [CI], 4.1-5.2), and median OS was 8.2 months (95% CI, 7.2-9.4). Median PFS after rechallenge for patients who discontinued first BRAFi(/MEKi) treatment due to progression was 3.1 months (95% CI, 2.7-4.0) versus 5.2 months (95% CI, 4.5-5.9) for patients who discontinued treatment for other reasons. Discontinuing first treatment due to progression and lactate dehydrogenase (LDH) levels greater than two times the upper limit of normal were associated with lower odds of response and worse PFS and OS. Symptomatic brain metastases were associated with worse survival, whereas a longer treatment interval between first treatment and rechallenge was associated with better survival. Responding to the first BRAFi(/MEKi) treatment was not associated with response or survival.

CONCLUSIONS

This study confirms that patients benefit from rechallenge. Elevated LDH levels, symptomatic brain metastases, and discontinuing first BRAFi(/MEKi) treatment due to progression are associated with less benefit from rechallenge. A prolonged treatment interval is associated with more benefit from rechallenge.

BRAF Mutated and Morphologically Spitzoid Tumors, a Subgroup of Melanocytic Neoplasms Difficult to Distinguish From True Spitz Neoplasms

Drivers of Spitz neoplasms include activating point mutations in HRAS and Spitz-associated genomic fusions. It has become evident that some BRAF -mutated melanocytic neoplasms can morphologically mimic Spitz tumors (STs). These have been termed BRAF mutated and morphologically spitzoid (BAMS). In this study, 17 experts from the International Melanoma Pathology Study Group assessed 54 cases which included 40 BAMS and 14 true STs. The participants reviewed the cases blinded to the genomic data and selected among several diagnostic options, including BAMS, ST, melanoma, and other. A total of 38% of all diagnostic selections in the BAMS cases were for BAMS, whereas 32% were for ST. In 22 of the BAMS cases, the favored diagnosis was BAMS, whereas in 17 of the BAMS cases, the favored diagnosis was ST. Among the 20 cases in the total group of 54 with the highest number of votes for ST, half were BAMS. Of BAMS, 75% had a number of votes for ST that was within the SD of votes for ST seen among true ST cases. There was poor interobserver agreement for the precise diagnosis of the BAMS (kappa = 0.16) but good agreement that these cases were not melanoma (kappa = 0.7). BAMS nevi/tumors can closely mimic Spitz neoplasms. Expert melanoma pathologists in this study favored a diagnosis of ST in nearly half of the BAMS cases. There are BAMS cases that even experts cannot morphologically distinguish from true Spitz neoplasms.

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.

The Impact of Next-generation Sequencing on Interobserver Agreement and Diagnostic Accuracy of Desmoplastic Melanocytic Neoplasms

Next-generation sequencing (NGS) is increasingly being utilized as an ancillary tool for diagnostically challenging melanocytic neoplasms. It is incumbent upon the pathology community to perform studies assessing the benefits and limitations of these tools in specific diagnostic scenarios. One of the most challenging diagnostic scenarios faced by skin pathologists involves accurate diagnosis of desmoplastic melanocytic neoplasms (DMNs). In this study, 20 expert melanoma pathologists rendered a diagnosis on 47 DMNs based on hematoxylin and eosin sections with demographic information. After submitting their diagnosis, the experts were given the same cases, but this time with comprehensive genomic sequencing results, and asked to render a diagnosis again. Identification of desmoplastic melanoma (DM) improved by 7%, and this difference was statistically significant (P<0.05). In addition, among the 15 melanoma cases, in the pregenomic assessment, only 12 were favored to be DM by the experts, while after genomics, this improved to 14 of the cases being favored to be DM. In fact, some cases resulting in metastatic disease had a substantial increase in the number of experts recognizing them as DM after genomics. The impact of the genomic findings was less dramatic among benign and intermediate-grade desmoplastic tumors (BIDTs). Interobserver agreement also improved, with the Fleiss multirater Kappa being 0.36 before genomics to 0.4 after genomics. NGS has the potential to improve diagnostic accuracy in the assessment of desmoplastic melanocytic tumors. The degree of improvement will be most substantial among pathologists with some background and experience in bioinformatics and melanoma genetics.

Response to checkpoint inhibition and targeted therapy in melanoma patients with concurrent haematological malignancies

BACKGROUND

Patients diagnosed with haematologic malignancies (HMs) have a higher risk of developing subsequent solid tumours, such as melanoma. Patients with HM were mostly excluded from clinical trials but potentially derive less benefit from immune checkpoint inhibitors (ICIs) due to disease- or treatment-related T- or B-cell dysfunction.

METHODS

All advanced melanoma patients treated with anti-PD-1-based treatment or targeted therapy between 2015 and 2021 were included from the prospective nationwide Dutch Melanoma Treatment Registry. Progression-free survival (PFS) and melanoma-specific survival (MSS) were analysed for patients with HM (HM+) and without HM (HM-). A cox model was used to account for confounders associated with PFS and MSS.

RESULTS

In total, 4638 advanced melanoma patients received first-line anti-PD-1 monotherapy (n = 1763), ipilimumab-nivolumab (n = 800), or BRAF(/MEK) inhibitors (n = 2075). Concurrent HMs were present for 46 anti-PD1-treated patients, 11 ipilimumab-nivolumab-treated patients and 43 BRAF(/MEK)-inhibitor-treated patients. In anti-PD-1-treated patients, the median PFS was 2.8 months for HM+ and 9.9 months for HM- (p = 0.01). MSS was 41.2 months for HM+ and 58.1 months for HM- (p = 0.00086). In multivariable analysis, the presence of an HM was significantly associated with higher risk of melanoma progression (HRadj 1.62; 95% confidence interval [95% CI] 1.15-2.29; p = 0.006) and melanoma-related death (HRadj 1.74; 95% CI 1.09-2.78; p = 0.020). Median PFS and MSS for first-line BRAF(/MEK-) inhibitor-treated HM+ and HM- patients were not significantly different.

CONCLUSIONS

Patients with HM and advanced melanoma show significantly worse melanoma-related outcomes when treated with ICI, but not targeted therapy, compared to patients without HM. Clinicians should be aware of potentially altered effectiveness of ICI in patients with active HM.

PRAME Staining in Sinonasal Mucosal Melanoma: A Single-Center Experience

BACKGROUND

Sinonasal mucosal melanoma (MM) is a rare, aggressive melanoma subtype. Complete surgical excision, with or without adjuvant radiotherapy, remains the cornerstone of treatment and yields adequate locoregional control. Metastatic MM is managed similarly to metastatic cutaneous melanoma but with poorer survival. PReferentially expressed Antigen in MElanoma (PRAME) has been identified as a potential diagnostic marker and therapeutic target in the treatment of cutaneous melanoma.

METHODS

Retrospective analysis of the clinical characteristics and immunohistochemical features of all sinonasal MM patients referred to the department of Head and Neck Surgical Oncology, UMC Utrecht Cancer Center, between 2011 and 2021 was performed. Single nucleotide polymorphism (SNP) array and next-generation sequencing (NGS) were performed in selected cases.

RESULTS

A total of 26 patients with an MM were included. The median follow-up duration was 15 months. At the end of follow-up, 13 patients had died due to progression of their disease, and one patient died of intercurrent disease. PRAME immunohistochemistry was performed in 23 out of 26 cases, all displaying PRAME expression. In two cases PRAME expression was present both within the melanoma cells and in melanocytes in adjacent mucosa. SNP array showed ≥ 5 copy number variants (CNV) in all tested cases, with a median of 29.5 CNVs (IQR 23.25-40). The three most common mutations identified by NGS were NRAS (7 cases) and NF1 (2 cases).

CONCLUSION

We show that expression of PRAME is common in sinonasal MM, making PRAME a useful ancillary diagnostic tool and a potential therapeutic target in sinonasal MM. The demonstrated occurrence of extensive presence of PRAME-positive melanocytes in the surrounding mucosa of sinonasal MM might explain the multifocal nature of melanoma in the (sinonasal) mucosa, and would be an extra argument for a PRAME targeting treatment in preventing local disease recurrence.

A Survival Tree of Advanced Melanoma Patients with Brain Metastases Treated with Immune Checkpoint Inhibitors

The efficacy of immune checkpoint inhibitors (ICIs) in patients with advanced melanoma that develop brain metastases (BM) remains unpredictable. In this study, we aimed to identify prognostic factors in patients with melanoma BM who are treated with ICIs. Data from advanced melanoma patients with BM treated with ICIs in any line between 2013 and 2020 were obtained from the Dutch Melanoma Treatment Registry. Patients were included from the time of the treatment of BM with ICIs. Survival tree analysis was performed with clinicopathological parameters as potential classifiers and overall survival (OS) as the response variable. In total, 1278 patients were included. Most patients were treated with ipilimumab-nivolumab combination therapy (45%). The survival tree analysis resulted in 31 subgroups. The median OS ranged from 2.7 months to 35.7 months. The strongest clinical parameter associated with survival in advanced melanoma patients with BM was the serum lactate dehydrogenase (LDH) level. Patients with elevated LDH levels and symptomatic BM had the worst prognosis. The clinicopathological classifiers identified in this study can contribute to optimizing clinical studies and can aid doctors in giving an indication of the patients' survival based on their baseline and disease characteristics.

[Melanocytoma, an intermediate entity between nevus and melanoma: implications of the WHO classification of melanocytic skin tumours]

The WHO classification of melanocytic skin tumours published in 2018 describes a new classification with nine different pathways based on molecular driver mutations, localization, clinical context and solar damage. The dichotomous concept of benign (nevus) versus malignant (melanoma) is replaced by a gradual concept starting with a benign nevus with progression into low to high grade intermediate melanocytic lesions, called melanocytoma, and ending at melanoma. The current European recommendation is (re-)excision with 2-5mm margin of low grade melanocytoma and with 5-10mm margin of high grade melanocytoma. Low grade melanocytoma needs no follow-up. For high grade melanocytoma a follow-up for at least 5 years every 6 months is recommended. Routine sentinel node procedure is not indicated. If diagnosis melanoma cannot be ruled out the lesions have to be treated as melanoma. Correct classification of a melanocytoma is a diagnostic challenge, but of high importance for therapeutic choices and prognosis.

Ambiguous melanocytic lesions: A retrospective cohort study of incidence and outcome of melanocytic tumor of uncertain malignant potential (MELTUMP) and superficial atypical melanocytic proliferation of uncertain significance (SAMPUS) in the Netherlands

BACKGROUND

Melanocytic tumor of uncertain malignant potential (MELTUMP) and superficial atypical melanocytic proliferation of uncertain significance (SAMPUS) are descriptive and provisional terms for melanocytic tumors with ambiguous histopathological features that are not easily classified as either benign or malignant.

OBJECTIVE

To investigate the incidence and clinical outcome of MELTUMP and SAMPUS in the Netherlands.

METHODS

In this retrospective cohort study, we reviewed all diagnoses of MELTUMP and SAMPUS from the Dutch Nationwide Pathology Databank from 1991 to October 1, 2021. Clinical outcome was studied for cases diagnosed until October 1, 2018.

RESULTS

A total of 1685 MELTUMP and 1957 SAMPUS were identified with an annual incidence of 150 to 300 cases. Metastatic behavior was seen in 0.7% of all initially diagnosed MELTUMP. All SAMPUS remained free of metastases.

LIMITATIONS

Reassessment of pathology slides and confirmation of clonality between primary and metastatic lesions remained outside the scope of this study.

CONCLUSION

Despite the 'uncertainty' in the nomenclature, our results demonstrate a low malignant potential for MELTUMP and no malignant potential for SAMPUS. We emphasize the importance of consultation for ambiguous melanocytic lesions and to limit the MELTUMP/SAMPUS terminology to legitimately uncertain or unclassifiable cases.

Time interval from primary melanoma to first distant recurrence in relation to patient outcomes in advanced melanoma

Since the introduction of BRAF(/MEK) inhibition and immune checkpoint inhibition (ICI), the prognosis of advanced melanoma has greatly improved. Melanoma is known for its remarkably long time to first distant recurrence (TFDR), which can be decades in some patients and is partly attributed to immune-surveillance. We investigated the relationship between TFDR and patient outcomes after systemic treatment for advanced melanoma. We selected patients undergoing first-line systemic therapy for advanced melanoma from the nationwide Dutch Melanoma Treatment Registry. The association between TFDR and progression-free survival (PFS) and overall survival (OS) was assessed by Cox proportional hazard regression models. The TFDR was modeled categorically, linearly, and flexibly using restricted cubic splines. Patients received anti-PD-1-based treatment (n = 1844) or BRAF(/MEK) inhibition (n = 1618). For ICI-treated patients with a TFDR <2 years, median OS was 25.0 months, compared to 37.3 months for a TFDR >5 years (P = .014). Patients treated with BRAF(/MEK) inhibition with a longer TFDR also had a significantly longer median OS (8.6 months for TFDR <2 years compared to 11.1 months for >5 years, P = .004). The hazard of dying rapidly decreased with increasing TFDR until approximately 5 years (HR 0.87), after which the hazard of dying further decreased with increasing TFDR, but less strongly (HR 0.82 for a TFDR of 10 years and HR 0.79 for a TFDR of 15 years). Results were similar when stratifying for type of treatment. Advanced melanoma patients with longer TFDR have a prolonged PFS and OS, irrespective of being treated with first-line ICI or targeted therapy.

Adjuvant treatment of in-transit melanoma: Narrowing the knowledge gap left by clinical trials

Few clinical trials address efficacy of adjuvant systemic treatment in patients with in-transit melanoma (ITM). This study describes adjuvant systemic therapy of ITM patients beyond clinical trials. In this study, we included stage III adjuvant-treated melanoma patients registered in the nationwide Dutch Melanoma Treatment Registry between July 2018 and December 2020. Patients were divided into three groups: nodal disease only, ITM only and ITM and nodal disease. Recurrence patterns, recurrence-free survival (RFS) and overall survival (OS) at 12-months were analyzed. In our study population of 1037 patients, 66.8% had nodal disease only, 16.7% had ITM only and 16.2% had ITM with nodal disease. RFS at 12-months was comparable in the nodal only and ITM only group (72.2% vs70.1%, P = .97) but lower in ITM and nodal disease patients (57.8%; P = .01, P < .01). Locoregional metastases occurred as first recurrence in 38.9% nodal disease only, 71.9% of ITM-only and 44.0% of ITM and nodal disease patients. Distant recurrences occurred in 42.3%, 18.8% and 36.0%, respectively (P = .02). 12-months OS was not significantly different for nodal disease only patients compared with ITM-only (94.4% vs 97.6%, P = .06) but was significantly higher for ITM-only compared with ITM and nodal disease patients (97.6% vs 91.0%, P < .01). In conclusion, we showed that in the adjuvant setting, RFS rates in ITM-only patients are similar to non-ITM, though better than in ITM and nodal disease patients. Adjuvant-treated ITM-only patients less often experience distant recurrences and have a superior OS compared with ITM and nodal disease patients.

Adjuvant BRAF-MEK Inhibitors versus Anti PD-1 Therapy in Stage III Melanoma: A Propensity-Matched Outcome Analysis

Adjuvant BRAF/MEK- and anti-PD-1 inhibition have significantly improved recurrence-free survival (RFS) compared to placebo in resected stage III BRAF-mutant melanoma. However, data beyond the clinical trial setting are limited. This study describes the toxicity and survival of patients treated with adjuvant BRAF/MEK inhibitors and compares outcomes to adjuvant anti-PD-1. For this study, stage III BRAF V600 mutant cutaneous melanoma patients treated with adjuvant BRAF/MEK-inhibition or anti-PD-1 were identified from the Dutch Melanoma Treatment Registry. BRAF/MEK- and anti-PD-1-treated patients were matched based on propensity scores, and RFS at 12 and 18 months were estimated. Between 1 July 2018 and 31 December 2021, 717 patients were identified. Of these, 114 patients with complete records were treated with BRAF/MEK therapy and 532 with anti-PD-1. Comorbidities (p = 0.04) and geographical region (p < 0.01) were associated with treatment choice. In 45.6% of BRAF/MEK-treated patients, treatment was prematurely discontinued. Grade ≥ 3 toxicity occurred in 11.5% of patients and was the most common cause of early discontinuation (71.1%). At 12 and 18 months, RFS in BRAF/MEK-treated patients was 85% and 70%, compared to 68% and 68% in matched anti-PD-1-treated patients (p = 0.03). In conclusion, comorbidities and geographical region determine the choice of adjuvant treatment in patients with resected stage III BRAF-mutant melanoma. With the currently limited follow-up, BRAF/MEK-treated patients have better RFS at 12 months than matched anti-PD-1-treated patients, but this difference is no longer observed at 18 months. Therefore, longer follow-up data are necessary to estimate long-term effectiveness.

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.

Association of Immune-Related Adverse Event Management With Survival in Patients With Advanced Melanoma

Importance

Management of checkpoint inhibitor-induced immune-related adverse events (irAEs) is primarily based on expert opinion. Recent studies have suggested detrimental effects of anti-tumor necrosis factor on checkpoint-inhibitor efficacy.

Objective

To determine the association of toxic effect management with progression-free survival (PFS), overall survival (OS), and melanoma-specific survival (MSS) in patients with advanced melanoma treated with first-line ipilimumab-nivolumab combination therapy.

Design, Setting, and Participants

This population-based, multicenter cohort study included patients with advanced melanoma experiencing grade 3 and higher irAEs after treatment with first-line ipilimumab and nivolumab between 2015 and 2021. Data were collected from the Dutch Melanoma Treatment Registry. Median follow-up was 23.6 months.

Main Outcomes and Measures

The PFS, OS, and MSS were analyzed according to toxic effect management regimen. Cox proportional hazard regression was used to assess factors associated with PFS and OS.

Results

Of 771 patients treated with ipilimumab and nivolumab, 350 patients (median [IQR] age, 60.0 [51.0-68.0] years; 206 [58.9%] male) were treated with immunosuppression for severe irAEs. Of these patients, 235 received steroids alone, and 115 received steroids with second-line immunosuppressants. Colitis and hepatitis were the most frequently reported types of toxic effects. Except for type of toxic effect, no statistically significant differences existed at baseline. Median PFS was statistically significantly longer for patients treated with steroids alone compared with patients treated with steroids plus second-line immunosuppressants (11.3 [95% CI, 9.6-19.6] months vs 5.4 [95% CI, 4.5-12.4] months; P = .01). Median OS was also statistically significantly longer for the group receiving steroids alone compared with those receiving steroids plus second-line immunosuppressants (46.1 months [95% CI, 39.0 months-not reached (NR)] vs 22.5 months [95% CI, 36.5 months-NR]; P = .04). Median MSS was also better in the group receiving steroids alone compared with the group receiving steroids plus second-line immunosuppressants (NR [95% CI, 46.1 months-NR] vs 28.8 months [95% CI, 20.5 months-NR]; P = .006). After adjustment for potential confounders, patients treated with steroids plus second-line immunosuppressants showed a trend toward a higher risk of progression (adjusted hazard ratio, 1.40 [95% CI, 1.00-1.97]; P = .05) and had a higher risk of death (adjusted hazard ratio, 1.54 [95% CI, 1.03-2.30]; P = .04) compared with those receiving steroids alone.

Conclusions and Relevance

In this cohort study, second-line immunosuppression for irAEs was associated with impaired PFS, OS, and MSS in patients with advanced melanoma treated with first-line ipilimumab and nivolumab. These findings stress the importance of assessing the effects of differential irAE management strategies, not only in patients with melanoma but also other tumor types.

BRAF and NRAS Mutation Status and Response to Checkpoint Inhibition in Advanced Melanoma

PURPOSE

Little is known about the effect of specific gene mutations on efficacy of immune checkpoint inhibitors in patients with advanced melanoma.

MATERIALS AND METHODS

All patients with advanced melanoma treated with first-line anti-PD-1 or ipilimumab-nivolumab between 2012 and 2021 in the nationwide Dutch Melanoma Treatment Registry were included in this cohort study. Objective response rate, progression-free survival (PFS), and overall survival (OS) were analyzed according to BRAF and NRAS status. A multivariable Cox model was used to analyze prognostic factors associated with PFS and OS.

RESULTS

In total, 1764 patients received anti-PD-1 and 759 received ipilimumab-nivolumab. No significant differences in PFS were found in the anti-PD-1 cohort. In the ipilimumab-nivolumab cohort, median PFS was significantly higher for BRAF-mutant melanoma (9.9 months; 95% CI, 6.8 to 17.2) compared with NRAS-mutant (4.8 months; 95% CI, 3.0 to 7.5) and double wild-type (5.3 months; 95% CI, 3.6 to 7.1). In multivariable analysis, BRAF-mutant melanoma was significantly associated with a lower risk of progression or death in the ipilimumab-nivolumab cohort. Median OS was significantly higher for BRAF-mutant melanoma compared with NRAS-mutant and double wild-type melanoma for both immune checkpoint inhibitor regimens.

CONCLUSION

Ipilimumab-nivolumab-treated patients with BRAF-mutant melanoma display improved PFS and OS compared with patients with NRAS-mutant and double wild-type melanoma. BRAF mutation status is a factor to consider while choosing between mono and dual checkpoint inhibition in advanced melanoma.

Response to immune checkpoint inhibitors in acral melanoma: A nationwide cohort study

BACKGROUND

Recent reports suggest the limited efficacy of immune checkpoints inhibitors in advanced acral melanoma (AM). This study aims to investigate the clinical outcomes of immune checkpoint inhibitors in patients with stage III and IV AM and compare them to cutaneous melanoma (CM).

METHODS

We included patients with advanced AM and CM treated with first-line anti-programmed cell death (PD)-1 monotherapy or ipilimumab-nivolumab registered in the prospective nationwide Dutch Melanoma Treatment Registry. Objective response rates, progression-free survival (PFS) and overall survival (OS) were calculated. A Cox proportional hazard model was used to assess the prognostic factors with PFS and OS.

RESULTS

In total, 2058 patients (88 AM and 1970 CM) with advanced melanoma were included. First-line objective response rates were 34% for AM versus 54% for CM in the advanced anti-PD-1 cohort and 33% for AM versus 53% for CM in the advanced ipilimumab-nivolumab cohort. The Median PFS was significantly shorter for anti-PD-1 treated AM patients (3.1 months; 95%CI: 2.8-5.6) than patients with CM (10.1 months; 95%CI: 8.5-12.2) (P < 0.001). In patients with advanced melanoma, AM was significantly associated with a higher risk of progression (HRadj 1.63; 95%CI: 1.26-2.11; P < 0.001) and death (HRadj 1.54; 95%CI: 1.15-2.06; P = 0.004) than CM.

CONCLUSIONS

This study shows lower effectiveness of anti-PD -1 monotherapy and ipilimumab-nivolumab in AM, with lower response rates, PFS and OS than CM. This group of patients should be prioritised in the development of alternative treatment strategies.

Computer-Aided Assessment of Melanocytic Lesions by Means of a Mitosis Algorithm

An increasing number of pathology laboratories are now fully digitised, using whole slide imaging (WSI) for routine diagnostics. WSI paves the road to use artificial intelligence (AI) that will play an increasing role in computer-aided diagnosis (CAD). In melanocytic skin lesions, the presence of a dermal mitosis may be an important clue for an intermediate or a malignant lesion and may indicate worse prognosis. In this study a mitosis algorithm primarily developed for breast carcinoma is applied to melanocytic skin lesions. This study aimed to assess whether the algorithm could be used in diagnosing melanocytic lesions, and to study the added value in diagnosing melanocytic lesions in a practical setting. WSI’s of a set of hematoxylin and eosin (H&E) stained slides of 99 melanocytic lesions (35 nevi, 4 intermediate melanocytic lesions, and 60 malignant melanomas, including 10 nevoid melanomas), for which a consensus diagnosis was reached by three academic pathologists, were subjected to a mitosis algorithm based on AI. Two academic and six general pathologists specialized in dermatopathology examined the WSI cases two times, first without mitosis annotations and after a washout period of at least 2 months with mitosis annotations based on the algorithm. The algorithm indicated true mitosis in lesional cells, i.e., melanocytes, and non-lesional cells, i.e., mainly keratinocytes and inflammatory cells. A high number of false positive mitosis was indicated as well, comprising melanin pigment, sebaceous glands nuclei, and spindle cell nuclei such as stromal cells and neuroid differentiated melanocytes. All but one pathologist reported more often a dermal mitosis with the mitosis algorithm, which on a regular basis, was incorrectly attributed to mitoses from mainly inflammatory cells. The overall concordance of the pathologists with the consensus diagnosis for all cases excluding nevoid melanoma (n = 89) appeared to be comparable with and without the use of AI (89% vs. 90%). However, the concordance increased by using AI in nevoid melanoma cases (n = 10) (75% vs. 68%). This study showed that in general cases, pathologists perform similarly with the aid of a mitosis algorithm developed primarily for breast cancer. In nevoid melanoma cases, pathologists perform better with the algorithm. From this study, it can be learned that pathologists need to be aware of potential pitfalls using CAD on H&E slides, e.g., misinterpreting dermal mitoses in non-melanotic cells.

Adjuvant treatment for melanoma in clinical practice - Trial versus reality

BACKGROUND

Little is known about outcomes of adjuvant-treated melanoma patients beyond the clinical trial setting. Since 2019, adjuvant-treated melanoma patients have been registered in the DMTR, a population-based registry to monitor the quality and safety of melanoma care in the Netherlands. This study aims to describe treatment patterns, relapse, and toxicity rates of adjuvant-treated melanoma patients beyond the clinical trial setting.

METHODS

Analyses were performed on adjuvant-treated melanoma patients included in the DMTR. Descriptive statistics were used to analyse patient-, and treatment characteristics. A baseline registration completeness analysis was performed, and an analysis on trial eligibility in clinical practice patients. Recurrence-free survival (RFS) at 12-months was estimated with the Kaplan-Meier method.

RESULTS

A total of 641 patients were treated with adjuvant anti-PD-1 therapy. RFS at 12-months was 70.6% (95% CI, 66.9-74.6) with a median follow-up of 12.8 months. Sex, stage of disease and Breslow thickness were associated with a higher hazard for RFS. Eighteen per cent of the anti-PD-1-treated patients developed grade ≥3 toxicity. Sixty-one per cent of patients prematurely discontinued anti-PD-1 therapy.

CONCLUSION

Adjuvant anti-PD-1 treatment of resected stage III/IV melanoma in daily practice showed slightly higher toxicity rates and more frequent premature discontinuation but similar RFS rates compared to trials.

The unfavorable effects of COVID-19 on Dutch advanced melanoma care

The COVID‐19 pandemic had a severe impact on medical care. Our study aims to investigate the impact of COVID‐19 on advanced melanoma care in the Netherlands. We selected patients diagnosed with irresectable stage IIIc and IV melanoma during the first and second COVID‐19 wave and compared them with patients diagnosed within the same time frame in 2018 and 2019. Patients were divided into three geographical regions. We investigated baseline characteristics, time from diagnosis until start of systemic therapy and postponement of anti‐PD‐1 courses. During both waves, fewer patients were diagnosed compared to the control groups. During the first wave, time between diagnosis and start of treatment was significantly longer in the southern region compared to other regions (33 vs 9 and 15 days, P‐value <.05). Anti‐PD‐1 courses were postponed in 20.0% vs 3.0% of patients in the first wave compared to the control period. Significantly more patients had courses postponed in the south during the first wave compared to other regions (34.8% vs 11.5% vs 22.3%, P‐value <.001). Significantly more patients diagnosed during the second wave had brain metastases and worse performance status compared to the control period. In conclusion, advanced melanoma care in the Netherlands was severely affected by the COVID‐19 pandemic. In the south, the start of systemic treatment for advanced melanoma was more often delayed, and treatment courses were more frequently postponed. During the second wave, patients were diagnosed with poorer patient and tumor characteristics. Longer follow‐up is needed to establish the impact on patient outcomes.

What's new?

Little is known about the effects of COVID‐19 on advanced melanoma care. In this study, the authors examined several quality indicators of care. They observed a worsening in baseline characteristics, longer time between diagnosis and start of treatment and more postponed anti‐PD‐1 antibody courses with differences between the northern, middle and southern regions. Future studies are necessary to assess the long‐term consequences of our observed changes in advanced melanoma care.

Genome-wide copy number variations as molecular diagnostic tool for cutaneous intermediate melanocytic lesions: a systematic review and individual patient data meta-analysis

Cutaneous intermediate melanocytic neoplasms with ambiguous histopathological features are diagnostically challenging. Ancillary cytogenetic techniques to detect genome-wide copy number variations (CNVs) might provide a valuable tool to allow accurate classification as benign (nevus) or malignant (melanoma). However, the CNV cut-off value to distinguish intermediate lesions from melanoma is not well defined. We performed a systematic review and individual patient data meta-analysis to evaluate the use of CNVs to classify intermediate melanocytic lesions. A total of 31 studies and 431 individual lesions were included. The CNV number in intermediate lesions (median 1, interquartile range [IQR] 0-2) was significantly higher (p<0.001) compared to that in benign lesions (median 0, IQR 0-1) and lower (p<0.001) compared to that in malignant lesions (median 6, IQR 4-11). The CNV number displayed excellent ability to differentiate between intermediate and malignant lesions (0.90, 95% CI 0.86-0.94, p<0.001). Two CNV cut-off points demonstrated a sensitivity and specificity higher than 80%. A cut-off of ≥3 CNVs corresponded to 85% sensitivity and 84% specificity, and a cut-off of ≥4 CNVs corresponded to 81% sensitivity and 91% specificity, respectively. This individual patient data meta-analysis provides a comprehensive overview of CNVs in cutaneous intermediate melanocytic lesions, based on the largest pooled cohort of ambiguous melanocytic neoplasms to date. Our meta-analysis suggests that a cut-off of ≥3 CNVs might represent the optimal trade-off between sensitivity and specificity in clinical practice to differentiate intermediate lesions from melanoma.

Development and Validation of Nomograms to Predict Local, Regional, and Distant Recurrence in Patients With Thin (T1) Melanomas

PURPOSE

Although the prognosis of patients with thin primary cutaneous melanomas (T1, ≤ 1.0 mm) is generally excellent, some develop recurrence. We sought to develop and validate a model predicting recurrences in patients with thin melanomas.

METHODS

A Dutch population-based cohort (n = 25,930, development set) and a cohort from an Australian melanoma treatment center (n = 2,968, validation set) were analyzed (median follow-up 6.7 and 12.0 years, respectively). Multivariable Cox models were generated for local, regional, and distant recurrence-free survival (RFS). Discrimination was assessed using Harrell's C-statistic for each outcome. Each nomogram performance was evaluated using calibration plots defining low-risk and high-risk groups as the lowest and top 5% of the nomogram risk score, respectively. The nomograms' C-statistics were compared with those of a model including the current American Joint Committee on Cancer staging parameters (T-stage and sentinel node status).

RESULTS

Local, regional, and distant recurrences were found in 209 (0.8%), 503 (1.9%), and 203 (0.8%) Dutch patients, respectively, and 23 (0.8%), 61 (2.1%), and 75 (2.5%) Australian patients, respectively. C-statistics of 0.79 (95% CI, 0.75 to 0.82) for local RFS, 0.77 (95% CI, 0.75 to 0.78) for regional RFS, and 0.80 (95% CI, 0.77 to 0.83) for distant RFS were obtained for the development model. External validation showed C-statistics of 0.80 (95% CI, 0.69 to 0.90), 0.76 (95% CI, 0.70 to 0.82), and 0.74 (95% CI, 0.69 to 0.80), respectively. Calibration plots showed a good match between predicted and observed rates. Using the nomogram, the C-statistic was increased by 9%-12% for the development cohort and by 11%-15% for the validation cohort, compared with a model including only T-stage and sentinel node status.

CONCLUSION

Most patients with thin melanomas have an excellent prognosis, but some develop recurrence. The presented nomograms can accurately identify a subgroup at high risk. An online calculator is available at www.melanomarisk.org.au.

Nationwide Outcomes of Advanced Melanoma According to BRAFV600 Status

OBJECTIVE

The aim of this study was to evaluate treatment patterns and overall survival (OS) of patients with BRAFV600 wild-type and BRAFV600-mutant advanced melanoma in the Netherlands.

METHODS

We selected patients of 18 years and over, diagnosed between 2016 and 2017 with unresectable stage IIIC or IV melanoma, registered in the Dutch Melanoma Treatment Registry. To assess the association of BRAFV600-mutation status with OS we used the Cox proportional-hazards model.

RESULTS

A total of 642 BRAFV600 wild-type and 853 mutant patients were included in the analysis. Median OS did not differ significantly between both groups, 15.2 months (95% confidence interval [CI]: 13.2-19.2) versus 20.6 months (95% CI: 18.3-25.0). Survival rates at 6 and 12 months were significantly lower for BRAFV600 wild-type patients compared with BRAFV600-mutant patients, 72.0% (95% CI: 68.6-75.6) and 56.0% (95% CI: 52.2-60.0) versus 83.4% (95% CI: 80.9-85.9) and 65.7% (95% CI: 62.6-69.0). Two-year survival was not significantly different between both groups, 41.1% (95% CI: 37.2-45.3) versus 47.0% (95% CI: 43.6-60.6). Between 0 and 10 months, BRAFV600 wild-type patients had a decreased survival with a hazard ratio for OS of 2.00 (95% CI: 1.62-2.46) but this effect disappeared after 10 months. At 12 months, BRAFV600-mutant patients had started with second-line systemic treatment more often compared with BRAFV600 wild-type patients (50% vs. 19%).

CONCLUSION

These results suggest that advanced BRAFV600 wild-type melanoma patients have worse survival than BRAFV600-mutated patients during the first 10 months after diagnosis because of less available treatment options.

First-line BRAF/MEK inhibitors versus anti-PD-1 monotherapy in BRAFV600-mutant advanced melanoma patients: a propensity-matched survival analysis

BACKGROUND

Anti-PD-1 antibodies and BRAF/MEK inhibitors are the two main groups of systemic therapy in the treatment of BRAF^V600-mutant advanced melanoma. Until now, data are inconclusive on which therapy to use as first-line treatment. The aim of this study was to use propensity score matching to compare first-line anti-PD-1 monotherapy vs. BRAF/MEK inhibitors in advanced BRAF^V600-mutant melanoma patients.

METHODS

We selected patients diagnosed between 2014 and 2017 with advanced melanoma and a known BRAF^V600-mutation treated with first-line BRAF/MEK inhibitors or anti-PD-1 antibodies, registered in the Dutch Melanoma Treatment Registry. Patients were matched based on their propensity scores using the nearest neighbour and the optimal matching method.

RESULTS

Between 2014 and 2017, a total of 330 and 254 advanced melanoma patients received BRAF/MEK inhibitors and anti-PD-1 monotherapy as first-line systemic therapy. In the matched cohort, patients receiving anti-PD-1 antibodies as a first-line treatment had a higher median and 2-year overall survival compared to patients treated with first-line BRAF/MEK inhibitors, 42.3 months (95% CI: 37.3-NE) vs. 19.8 months (95% CI: 16.7-24.3) and 65.4% (95% CI: 58.1-73.6) vs. 41.7% (95% CI: 34.2-51.0).

CONCLUSIONS

Our data suggest that in the matched BRAF^V600-mutant advanced melanoma patients, anti-PD-1 monotherapy is the preferred first-line treatment in patients with relatively favourable patient and tumour characteristics.

Expanding spectrum of "spitzoid" lesions: a small series of 4 cases with MAP2K1 mutations

The molecular background of a significant proportion of spitzoid neoplasms is still unknown. Recently, activating mutations in MAP2K1 have been described in a few spitzoid lesions, but not in benign Spitz nevi. We report four cases of melanocytic tumors with spitzoid features in which a MAP2K1 mutation was detected. The lesions did not show a single distinct phenotype and ranged from benign to malignant. Two cases resembled desmoplastic Spitz nevi. Based on the combination of morphological, immunohistochemical, and molecular findings, one case was classified as benign, one as probably benign, possibly intermediate low-grade (MELTUMP—melanocytic tumor of unknown malignant potential), one case was classified as intermediate (MELTUMP), and one case was considered a superficial spreading melanoma with spitzoid features. Based on this, we conclude that MAP2K1 mutations can indicate a spitzoid genetic signature and can be found in both benign and malignant spitzoid neoplasms.

Validation of Whole-slide Digitally Imaged Melanocytic Lesions: Does Z-Stack Scanning Improve Diagnostic Accuracy?

Background

Accurate diagnosis of melanocytic lesions is challenging, even for expert pathologists. Nowadays, whole-slide imaging (WSI) is used for routine clinical pathology diagnosis in several laboratories. One of the limitations of WSI, as it is most often used, is the lack of a multiplanar focusing option. In this study, we aim to establish the diagnostic accuracy of WSI for melanocytic lesions and investigate the potential accuracy increase of z-stack scanning. Z-stack enables pathologists to use a software focus adjustment, comparable to the fine-focus knob of a conventional light microscope.

Materials and Methods

Melanocytic lesions (n = 102) were selected from our pathology archives: 35 nevi, 5 spitzoid tumors of unknown malignant potential, and 62 malignant melanomas, including 10 nevoid melanomas. All slides were scanned at a magnification comparable to use of a ×40 objective, in z-stack mode. A ground truth diagnosis was established on the glass slides by four academic dermatopathologists with a special interest in the diagnosis of melanoma. Six nonacademic surgical pathologists subspecialized in dermatopathology examined the cases by WSI.

Results

An expert consensus diagnosis was achieved in 99 (97%) of cases. Concordance rates between surgical pathologists and the ground truth varied between 75% and 90%, excluding nevoid melanoma cases. Concordance rates of nevoid melanoma varied between 10% and 80%. Pathologists used the software focusing option in 7%-28% of cases, which in 1 case of nevoid melanoma resulted in correcting a misdiagnosis after finding a dermal mitosis.

Conclusion

Diagnostic accuracy of melanocytic lesions based on glass slides and WSI is comparable with previous publications. A large variability in diagnostic accuracy of nevoid melanoma does exist. Our results show that z-stack scanning, in general, does not increase the diagnostic accuracy of melanocytic.

Is a single day patient friendly methyl aminolevulinate photodynamic therapy illumination scheme for superficial basal cell carcinoma feasible? A randomized multicenter pilot trial

BACKGROUND

Topical methyl aminolevulinate photodynamic therapy (MAL-PDT) is highly effective for the treatment of superficial basal cell carcinoma (sBCC). Current European treatment protocol requires two hospital visits, which is costly and unpractical. The aim of this study was to evaluate the efficacy of fractionated MAL-PDT, using two light fractions at 3 and 4 h compared to illumination at 3 and 5 h after MAL-application.

METHODS

Thirty patients were randomized into two groups. The first group received illumination at 3 and 4 h (20 + 55 J/cm²) after MAL-application (3/4 group). In the other group, two light fractions were performed at 3 and 5 h (20 + 55 J/cm²) after MAL-application (3/5 group). The lesion response was evaluated at 3 and 12 months posttreatment.

RESULTS

In the 3/5 group, 70.0% showed a complete response (CR) at 3 months compared to 63.6% in the other group. At 12 months, 100% showed a CR in the 3/5 group compared to 80.0% in the other group. However, most failures/recurrences were eventually due to the presence of a more aggressive BCC subtype, mostly caused by sampling error of the primary punch biopsy.

CONCLUSION

Single day protocol for MAL-PDT for sBCC is feasible and this study shows promising results.

New insights into naevoid melanomas: a clinicopathological reassessment

AIMS

Because the term 'naevoid melanoma' has variable clinical and pathological interpretations, we aimed to clarify the features of melanomas referred to as naevoid.

METHODS AND RESULTS

A review was undertaken of 102 melanomas diagnosed histopathologically as naevoid melanomas and ascertained by European Organization for Research and Treatment of Cancer Melanoma Group Subcommittee pathologists from their records. We found these could be classified morphologically into three groups. Thirteen melanomas were overlying genuine naevi and were therefore excluded. Of the 89 melanomas considered to be naevoid, 11 presented clinically as exophytic papillomatous nodules with little junctional component and composed of small atypical cells showing numerous mitoses and no change with depth; we termed these 'papillomatous naevoid' melanomas. The other 78 were flat or only slightly raised, and had a superficial spreading melanoma-like component with maturation to a small cell, but still an atypical, dermal component; we termed these 'maturing naevoid' melanomas. We showed that papillomatous and maturing naevoid melanomas also have differing immunochemical profiles. Preliminary clinical follow-up suggested different outcomes for these two naevoid melanoma types.

CONCLUSIONS

Melanomas that have been classified as naevoid melanomas comprise two types with distinct clinical, histopathological and immunohistochemical features that may also be prognostically significant.

Exploring the Role of IL-32 in HIV-Related Kaposi Sarcoma

The intracellular proinflammatory mediator IL-32 is associated with tumor progression; however, the mechanisms remain unknown. We studied IL-32 mRNA expression as well as expression of other proinflammatory cytokines and mediators, including IL-1α, IL-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, the proangiogenic and antiapoptotic enzyme cyclooxygenase-2, the IL-8 receptor C-X-C chemokine receptor (CXCR) 1, and the intracellular kinase focal adhesion kinase-1. The interaction of IL-32 expression with expression of IL-6, TNF-α, IL-8, and cyclooxygenase-2 was also investigated. Biopsy specimens of 11 HIV-related, 7 non-HIV-related Kaposi sarcoma (KS), and 7 normal skin tissues (NSTs) of Dutch origin were analyzed. RNA was isolated from the paraffin material, and gene expression levels of IL-32 α, β, and γ isoforms, IL1a, IL1b, IL6, IL8, TNFA, PTGS2, CXCR1, and PTK2 were determined using real-time quantitative PCR. Significantly higher expression of IL-32β and IL-32γ isoforms was observed in HIV-related KS biopsy specimens compared with non-HIV-related KS and NST. The splicing ratio of the IL-32 isoforms showed IL-32γ as the highest expressed isoform, followed by IL-32β, in HIV-related KS cases compared with non-HIV-related KS and NST. Our data suggest a possible survival mechanism by the splicing of IL-32γ to IL-32β and also IL-6, IL-8, and CXCR1 signaling pathways to reverse the proapoptotic effect of the IL-32γ isoform, leading to tumor cell survival and thus favoring tumor progression.

Dutch Melanoma Treatment Registry: Quality assurance in the care of patients with metastatic melanoma in the Netherlands

BACKGROUND

In recent years, the treatment of metastatic melanoma has changed dramatically due to the development of immune checkpoint and mitogen-activated protein (MAP) kinase inhibitors. A population-based registry, the Dutch Melanoma Treatment Registry (DMTR), was set up in July 2013 to assure the safety and quality of melanoma care in the Netherlands. This article describes the design and objectives of the DMTR and presents some results of the first 2 years of registration.

METHODS

The DMTR documents detailed information on all Dutch patients with unresectable stage IIIc or IV melanoma. This includes tumour and patient characteristics, treatment patterns, clinical outcomes, quality of life, healthcare utilisation, informal care and productivity losses. These data are used for clinical auditing, increasing the transparency of melanoma care, providing insights into real-world cost-effectiveness and creating a platform for research.

RESULTS

Within 1 year, all melanoma centres were participating in the DMTR. The quality performance indicators demonstrated that the BRAF inhibitors and ipilimumab have been safely introduced in the Netherlands with toxicity rates that were consistent with the phase III trials conducted. The median overall survival of patients treated with systemic therapy was 10.1 months (95% confidence interval [CI] 9.1-11.1) in the first registration year and 12.7 months (95% CI 11.6-13.7) in the second year.

CONCLUSION

The DMTR is the first comprehensive multipurpose nationwide registry and its collaboration with all stakeholders involved in melanoma care reflects an integrative view of cancer management. In future, the DMTR will provide insights into challenging questions regarding the definition of possible subsets of patients who benefit most from the new drugs.

Copy number variation analysis and methylome profiling of a GNAQ-mutant primary meningeal melanocytic tumor and its liver metastasis

Primary meningeal melanocytic tumors have genetic similarities with uveal melanomas, including GNAQ or GNA11 mutations. While BAP1 mutations and loss of chromosome 3 have adverse prognostic meaning in uveal melanoma, genetic alterations associated with metastasis have not been investigated in primary meningeal melanocytic tumors. We describe a 43-year-old female with a GNAQ-mutated, BAP1-wt melanocytic tumor originating in the parietal brain region and liver metastases 4years after initial diagnosis. After repeated surgery and chemotherapy she was treated with the immunomodulatory agent ipilimumab. Tissue from the primary and recurrent intracranial tumor (histologically originally diagnosed as intermediate-grade melanocytoma resp. melanoma) and from the liver metastasis was investigated for genome-wide copy number variations and DNA methylation profile. Complete loss of 10p and 19p, partial loss of 16p and a small deletion on 10q were only present in the liver metastasis and not in the intracranial tumors. The DNA methylation profiles of the intracranial tumors and the liver metastasis resembled those of meningeal melanocytomas. In conclusion, in this report we show that a distant metastasis of a meningeal melanocytic tumor has a similar methylation profile as the primary tumor and suggest that particular copy number variations may be associated with metastatic behavior.

Multispectral imaging for highly accurate analysis of tumour-infiltrating lymphocytes in primary melanoma

AIMS

The quality and quantity of the infiltration of immune cells into tumour tissues have substantial impacts on patients' clinical outcomes, and are associated with response to immunotherapy. Therefore, the precise analysis of tumour-infiltrating lymphocytes (TILs) is becoming an important additional pathological biomarker. Analysis of TILs is usually performed semiquantitatively by pathologists on haematoxylin and eosin-stained or immunostained tissue sections. However, automated quantification outperforms semiquantitative approaches, and is becoming the standard. Owing to the presence of melanin pigment, this approach is seriously hampered in melanoma, because the spectrum of melanin lies close to that of commonly used immunohistochemical stains. Aim of this study is to overcome the technical issues due to the presence of melanin for an automated and accurate quantification of TILs in melanoma.

METHODS AND RESULTS

Here, we successfully applied a novel multispectral imaging (MSI) technique to enumerate T cells in human primary melanomas. This microscopy technique combines imaging with spectroscopy to obtain both quantitative expression data and the tissue distributions of different cellular markers. We demonstrate that MSI allows complete and accurate analysis of TILs, successfully avoiding the blurring of images by melanin pigments, in whole tissue slide primary melanoma lesions, which could otherwise not be accurately detected by conventional digital image methodologies.

CONCLUSIONS

Our study highlights the potential of MSI for accurate assessment of immune cell infiltrates, including those in notoriously difficult tissues, such as pigmented melanomas. Quantification of tumour infiltration by different immune cell types is crucial in the search for new biomarkers to predict patient responses to immunotherapies. Our findings show that this innovative microscopy technique is an important extension of the armamentarium of pathologists.

Effective Clinical Responses in Metastatic Melanoma Patients after Vaccination with Primary Myeloid Dendritic Cells

PURPOSE

Thus far, dendritic cell (DC)-based immunotherapy of cancer was primarily based on in vitro-generated monocyte-derived DCs, which require extensive in vitro manipulation. Here, we report on a clinical study exploiting primary CD1c(+) myeloid DCs, naturally circulating in the blood.

EXPERIMENTAL DESIGN

Fourteen stage IV melanoma patients, without previous systemic treatment for metastatic disease, received autologous CD1c(+) myeloid DCs, activated by only brief (16 hours) ex vivo culture and loaded with tumor-associated antigens of tyrosinase and gp100.

RESULTS

Our results show that therapeutic vaccination against melanoma with small amounts (3-10 × 10(6)) of myeloid DCs is feasible and without substantial toxicity. Four of 14 patients showed long-term progression-free survival (12-35 months), which directly correlated with the development of multifunctional CD8(+) T-cell responses in three of these patients. In particular, high CD107a expression, indicative for cytolytic activity, and IFNγ as well as TNFα and CCL4 production was observed. Apparently, these T-cell responses are essential to induce tumor regression and promote long-term survival by stalling tumor growth.

CONCLUSIONS

We show that vaccination of metastatic melanoma patients with primary myeloid DCs is feasible and safe and results in induction of effective antitumor immune responses that coincide with improved progression-free survival. Clin Cancer Res; 22(9); 2155-66. ©2015 AACR.

T-cell Landscape in a Primary Melanoma Predicts the Survival of Patients with Metastatic Disease after Their Treatment with Dendritic Cell Vaccines

Tumor-infiltrating lymphocytes appear to be a predictor of survival in many cancers, including cutaneous melanoma. We applied automated multispectral imaging to determine whether density and distribution of T cells within primary cutaneous melanoma tissue correlate with survival of metastatic melanoma patients after dendritic cell (DC) vaccination. CD3(+) T cell infiltration in primary tumors from 77 metastatic melanoma patients was quantified using the ratio of intratumoral versus peritumoral T-cell densities (I/P ratio). Patients with longer survival after DC vaccination had stronger T-cell infiltration than patients with shorter survival in a discovery cohort of 19 patients (P = 0.000026) and a validation cohort of 39 patients (P = 0.000016). I/P ratio was the strongest predictor of survival in a multivariate analysis including M substage and serum lactate dehydrogenase level. To evaluate I/P ratio as a predictive biomarker, we analyzed 19 chemotherapy-treated patients. Longer survival times of DC-vaccinated compared with chemotherapy-treated patients was observed for high (P = 0.000566), but not low (P = 0.154) I/P ratios. In conclusion, T-cell infiltration into primary melanoma is a strong predictor of survival after DC vaccination in metastatic melanoma patients who, on average, started this therapy several years after primary tumor resection. The infiltration remains predictive even after adjustment for late-stage prognostic markers. Our findings suggest that the I/P ratio is a potential predictive biomarker for treatment selection. Cancer Res; 76(12); 3496-506. ©2016 AACR.

Prophylactic vaccines are potent activators of monocyte-derived dendritic cells and drive effective anti-tumor responses in melanoma patients at the cost of toxicity

Dendritic cell (DC)-based immunotherapy is explored worldwide in cancer patients, predominantly with DC matured with pro-inflammatory cytokines and prostaglandin E₂. We studied the safety and efficacy of vaccination with monocyte-derived DC matured with a cocktail of prophylactic vaccines that contain clinical-grade Toll-like receptor ligands (BCG, Typhim, Act-HIB) and prostaglandin E₂ (VAC-DC). Stage III and IV melanoma patients were vaccinated via intranodal injection (12 patients) or combined intradermal/intravenous injection (16 patients) with VAC-DC loaded with keyhole limpet hemocyanin (KLH) and mRNA encoding tumor antigens gp100 and tyrosinase. Tumor antigen-specific T cell responses were monitored in blood and skin-test infiltrating-lymphocyte cultures. Almost all patients mounted prophylactic vaccine- or KLH-specific immune responses. Both after intranodal injection and after intradermal/intravenous injection, tumor antigen-specific immune responses were detected, which coincide with longer overall survival in stage IV melanoma patients. VAC-DC induce local and systemic CTC grade 2 and 3 toxicity, which is most likely caused by BCG in the maturation cocktail. The side effects were self-limiting or resolved upon a short period of systemic steroid therapy. We conclude that VAC-DC can induce functional tumor-specific responses. Unfortunately, toxicity observed after vaccination precludes the general application of VAC-DC, since in DC maturated with prophylactic vaccines BCG appears to be essential in the maturation cocktail.

SF3B1 and EIF1AX mutations occur in primary leptomeningeal melanocytic neoplasms; yet another similarity to uveal melanomas

Introduction

Like uveal melanomas, primary leptomeningeal melanocytic neoplasms (LMNs) frequently carry GNAQ and GNA11 mutations. However, it is currently unknown whether these LMNs harbor mutations in BAP1, SF3B1 and/or EIF1AX like uveal melanomas as well. In this study, we used Sanger sequencing for the detection of mutations in SF3B1 (hotspots in exon 14 and 15) and EIF1AX (exon 1 and 2 and flanking intronic regions) in a series of 24 primary LMNs. Additionally, BAP1 immunohistochemistry was used as a surrogate marker for the detection of inactivating mutations in the BAP1 gene.

Results

Mutations in either SF3B1 or EIF1AX were identified in 8 out of 24 primary LMNs (33 %). The presence of these mutations was mutually exclusive and occurred in primary LMNs of different malignancy grades (melanocytomas, intermediate-grade melanocytic tumors, melanomas). Complete absence of nuclear BAP1 staining as is typically seen in BAP1-mutated tumors was not observed.

Conclusions

Our finding that an SF3B1 or EIF1AX mutation is present in a substantial subset of primary LMNs underscores that these tumors genetically resemble uveal melanoma and are different from cutaneous melanoma at the genetic level. This information may not only aid in the differential diagnosis of primary versus metastatic melanocytic tumor in/around the central nervous system, but also in the identification of more promising therapeutic approaches targeting the molecular pathways involved in the oncogenesis of LMNs. As none of the primary LMNs in our series showed complete loss of nuclear BAP1 protein, it is unlikely that BAP1 mutations are frequent in these tumors but the role of this gene warrants further investigation.

Primary melanocytic tumors of the central nervous system: a review with focus on molecular aspects

Primary melanocytic tumors of the central nervous system (CNS) represent a spectrum of rare tumors. They can be benign or malignant and occur in adults as well as in children, the latter often in the context of neurocutaneous melanosis. Until recently, the genetic alterations in these tumors were largely unknown. This is in contrast with cutaneous and uveal melanomas, which are known to harbor distinct oncogenic mutations that can be used as targets for treatment with small-molecule inhibitors in the advanced setting. Recently, novel insights in the molecular alterations underlying primary melanocytic tumors of the CNS were obtained, including different oncogenic mutations in tumors in adult patients (especially GNAQ, GNA11) vs. children (especially NRAS). In this review, the focus is on molecular characteristics of primary melanocytic tumors of the CNS. We summarize what is known about their genetic alterations and discuss implications for pathogenesis and differential diagnosis with other pigmented tumors in or around the CNS. Finally, new therapeutic options with targeted therapy are discussed.

Update on Molecular Pathology of Cutaneous Melanocytic Lesions: What is New in Diagnosis and Molecular Testing for Treatment?

In this article, we give an update on recent findings regarding molecular pathology in cutaneous melanocytic tumors. The focus lies on use of genetics in the diagnosis of distinct subtypes of spitzoid tumors that are often characterized by specific phenotypic–genotypic alterations that can frequently be recognized by adequate histological examination. Typical illustrating cases are given in order to increase recognition of these lesions in daily dermatopathology practice. New molecular findings in the pathogenesis of congenital melanocytic tumors and neurocutaneous melanosis are reviewed. In addition, use of mutation analysis in the differential diagnosis of melanoma metastasis is discussed. Finally, application of mutation analysis in targeted therapy in advanced melanoma with advantages of new techniques such as next generation sequencing is described.

Prospective differentiation of clinically difficult to distinguish nodular basal cell carcinomas and intradermal nevi by non-invasive Reflectance Confocal Microscopy: a case series study

BACKGROUND

Clinical differentiation between a nodular basal cell carcinoma (nBCC) and a benign intradermal nevus can be difficult. Even with additional dermoscopic evaluation, a correct diagnosis may be difficult. Currently, histopathological examination of a biopsy is the gold standard to differentiate between these lesions. However, this is an invasive technique and sampling errors can occur. In vivo Reflectance Confocal Microscopy (RCM) is a non-invasive technique to evaluate a skin lesion at a microscopic level. RCM features of nBCCs and intradermal nevi have been described in research setting. However, the use of RCM for prospective differentiation between difficult to diagnose nodules into nBCCs and intradermal nevi in clinical practice has not been demonstrated yet.

OBJECTIVE

In this study, we aim to address a common clinical scenario; to differentiate clinically and dermoscopically difficult to distinguish nodules, into nBCCs and intradermal nevi by RCM.

MATERIAL AND METHODS

Six patients with clinically and dermoscopically difficult to distinguish nodular skin lesions were evaluated by RCM to differentiate prospectively between nBCCs and intradermal nevi. In five out of six cases, a 3 mm punch biopsy was obtained to confirm the RCM diagnosis.

RESULTS

Observed RCM features that allowed differentiation between nBCCs and intradermal nevi were the dermal-epidermal junction patterns, the appearance of the nests and the degree of vascularization.

CONCLUSIONS

This case series study demonstrates the value of non-invasive in vivo RCM imaging in routine patient care, with respect to the prospective diagnosis of clinically difficult to distinguish nBCCs and intradermal nevi. Subsequently, biopsies of benign lesions in cosmetic areas could be avoided.