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Background: The long-term effectiveness of immune checkpoint inhibitor (ICI) rechallenge for progressive or recurrent advanced melanoma following previous disease control induced by ICI has not been thoroughly described in the literature. Patients and methods: In this retrospective multicenter national real-life study, we enrolled patients who had been rechallenged with an ICI after achieving disease control with a first course of ICI, which was subsequently interrupted. The primary objective was to evaluate tumor response, while the secondary objectives included assessing the safety profile, identifying factors associated with tumor response, and evaluating survival outcomes. Results: A total of 85 patients from 12 centers were included in the study. These patients had advanced (unresectable stage III or stage IV) melanoma that had been previously treated and controlled with a first course of ICI before undergoing rechallenge with ICI. The rechallenge treatments consisted of pembrolizumab (n = 44, 52%), nivolumab (n = 35, 41%), ipilimumab (n = 2, 2%), or ipilimumab plus nivolumab (n = 4, 5%). The best overall response rate was 54%. The best response was a complete response in 30 patients (35%), a partial response in 16 patients (19%), stable disease in 18 patients (21%) and progressive disease in 21 patients (25%). Twenty-eight adverse events (AEs) were reported in 23 patients (27%), including 18 grade 1–2 AEs in 14 patients (16%) and 10 grade 3–4 AEs in nine patients (11%). The median progression-free survival (PFS) was 21 months, and the median overall survival (OS) was not reached at the time of analysis. Patients who received another systemic treatment (chemotherapy, targeted therapy or clinical trial) between the two courses of ICI had a lower response to rechallenge (p = 0.035) and shorter PFS (p = 0.016). Conclusion: Rechallenging advanced melanoma patients with ICI after previous disease control induced by these inhibitors resulted in high response rates (54%) and disease control (75%). Therefore, ICI rechallenge should be considered as a relevant therapeutic option.

BackgroundPathogenic variants (PV) ofCTNNA1are found in families fulfilling criteria for hereditary diffuse gastric cancer (HDGC) but no risk estimates were available until now. The aim of this study is to evaluate diffuse gastric cancer (DGC) risks for carriers of germlineCTNNA1PV.MethodsData from published CTNNA1 families were updated and new families were identified through international collaborations. The cumulative risk of DGC by age for PV carriers was estimated with the genotype restricted likelihood (GRL) method, taking into account non-genotyped individuals and conditioning on all observed phenotypes and genotypes of the index case to obtain unbiased estimates. A non-parametric (NP) and the Weibull functions were used to model the shape of penetrance function with the GRL. Kaplan-Meier incidence curve and standardised incidence ratios were also computed. A ‘leave-one-out’ strategy was used to evaluate estimate uncertainty.ResultsThirteen families with 46 carriers of PV were included. The cumulative risks of DGC at 80 years for carriers ofCTNNA1PV are 49% and 57%, respectively with the Weibull GRL and NP GRL methods. Risk ratios to population incidence reach particularly high values at early ages and decrease with age. At 40 years, they are equal to 65 and 833, respectively with the Weibull GRL and NP GRL.ConclusionThis is the largest series ofCTNNA1families that provides the first risk estimates of GC. These data will help to improve management and surveillance for these patients and support inclusion ofCTNNA1in germline testing panels.

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Purpose: The emergence of skin tumors in patients treated with sorafenib or with more recent BRAF inhibitors is an intriguing and potentially serious event. We carried out a clinical, pathologic, and molecular study of skin lesions occurring in patients receiving sorafenib.Experimental Design: Thirty-one skin lesions from patients receiving sorafenib were characterized clinically and pathologically. DNA extracted from the lesions was screened for mutation hot spots of HRAS, NRAS, KiRAS, TP53, EGFR, BRAF, AKT1, PI3KCA, TGFBR1, and PTEN. Biological effect of sorafenib was studied in vivo in normal skin specimen and in vitro on cultured keratinocytes.Results: We observed a continuous spectrum of lesions: from benign to more inflammatory and proliferative lesions, all seemingly initiated in the hair follicles. Eight oncogenic HRAS, TGFBR1, and TP53 mutations were found in 2 benign lesions, 3 keratoacanthomas (KA) and 3 KA-like squamous cell carcinoma (SCC). Six of them correspond to the typical UV signature. Treatment with sorafenib led to an increased keratinocyte proliferation and a tendency toward increased mitogen-activated protein kinase (MAPK) pathway activation in normal skin.Sorafenib induced BRAF–CRAF dimerization in cultured keratinocytes and activated CRAF with a dose-dependent effect on MAP-kinase pathway activation and on keratinocyte proliferation.Conclusion: Sorafenib induces keratinocyte proliferation in vivo and a time- and dose-dependent activation of the MAP kinase pathway in vitro. It is associated with a spectrum of lesions ranging from benign follicular cystic lesions to KA-like SCC. Additional and potentially preexisting somatic genetic events, like UV-induced mutations, might influence the evolution of benign lesions to more proliferative and malignant tumors. Clin Cancer Res; 18(1); 263–72. ©2011 AACR.

Vemurafenib-induced BRAF-CRAF dimerization (2 µM, 24h) detected by in situ PLA in SK-MEL2 cell line is not decreased by the adjunction of MEK inhibitor PD0325901 (1µM, 24h): each red dot represents a BRAF-CRAF heterodimer. The cells were counterstained with DAPI (blue).

BRAF inhibitors (BRAFi) elicit therapeutic responses in metastatic melanoma, but alarmingly, also induce the formation of secondary benign and malignant skin tumors. Here, we report the emergence and molecular characterization of 73 skin and extracutaneous tumors in 31 patients who underwent BRAFi therapy. The majority of patients presented with classic epidermal tumors such as verrucous papillomas, keratoacanthomas, and squamous cell carcinomas (SCC). However, 15 patients exhibited new or rapidly progressing tumors distinct from these classic subtypes, such as lymph node metastasis, new melanomas, and genital and oral mucosal SCCs. Genotyping of the tumors revealed that oncogenic RAS mutations were found in 58% of the evaluable tumor samples (38/66) and 49% of the control tumors from patients not treated with BRAFi (30/62). Notably, proximity ligation assays demonstrated that BRAF–CRAF heterodimerization was increased in fixed tumor samples from BRAFi-treated patients compared with untreated patients. Our findings reveal that BRAF–CRAF complex formation is significantly associated with BRAFi treatment, and may therefore serve as a useful biomarker of BRAFi-induced cutaneous and extracutaneous tumor formation. Cancer Res; 76(6); 1476–84. ©2016 AACR.

Supplementary figure legends

Tumoral and non tumoral biospies from patients treated with or without BRAF inhibitors: Mutational status, pERK level and BRAF-CRAF PLA score.

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Proximity Ligation Assay principle. Two primary antibodies recognize the two antigens BRAF and CRAF. Specific secondary antibodies (Probes) bind to the primary antibodies and are bound to a unique short DNA. When the PLA probes are in close proximity, the DNA strands can interact. After joining they are amplified via rolling circle amplification (RCA) using a polymerase. The signal is easily made visible as a distinct brown or fluorescent dot after enzymatic conversion of a substrate.

PDF file - 507K, Koilocyte-like cells observed in an HPV negative verrucous papilloma (S1); H&E and pERK staining of gastric epithelium from mice treated for 60 days with 60 mg/kg Vemurafenib (S2); pERK staining of Vemurafenib and vehicle treated cSCC (S3); Reduced hyperkeratosis and improved grooming of K14-HPV16 mice treated with PD0325901 (S4); cSCC tumor response after treatment with 3 mg/kg PD0325901 (S5).

PDF file - 50K, RAS mutation and HPV status of cutaneous lesions by histological type.

Treatment with RAF inhibitors such as vemurafenib causes the development of cutaneous squamous cell carcinomas (cSCC) or keratoacanthomas as a side effect in 18% to 30% of patients. It is known that RAF inhibitors activate the mitogen—activated protein kinase (MAPK) pathway and stimulate growth of RAS-mutated cells, possibly accounting for up to 60% of cSCC or keratoacanthoma lesions with RAS mutations, but other contributing events are obscure. To identify such events, we evaluated tumors from patients treated with vemurafenib for the presence of human papilloma virus (HPV) DNA and identified 13% to be positive. Using a transgenic murine model of HPV-driven cSCC (K14-HPV16 mice), we conducted a functional test to determine whether administration of RAF inhibitors could promote cSCC in HPV-infected tissues. Vemurafenib treatment elevated MAPK markers and increased cSCC incidence from 22% to 70% in this model. Furthermore, 55% of the cSCCs arising in vemurafenib-treated mice exhibited a wild-type Ras genotype, consistent with the frequency observed in human patients. Our results argue that HPV cooperates with vemurafenib to promote tumorigenesis, in either the presence or absence of RAS mutations. Cancer Res; 74(8); 2238–45. ©2014 AACR.

This study aimed to assess the prognostic value of thyroid dysfunctions in metastatic melanoma patients on anti-programmed death-1 (anti-PD-1). A total of 110 stage IV or inoperable stage III melanoma patients treated with anti-PD-1 alone or in association with anti-CTLA-4 (T-lymphocyte antigen-4) antibody from January 2015 to December 2017 at our institution were enrolled in this retrospective study. Median follow-up was 32.8 months. Transitory thyroid dysfunctions and permanent thyroid dysfunctions were distinguished. The main criterion was progression-free survival. Secondary criteria were best response and overall survival. Survival curves were compared with log-rank tests and a cox proportional hazard ratio model was used to adjust patients and melanoma characteristics. Thirty-eight (35%) thyroid dysfunctions were observed during the follow-up, including 25 transitory thyroid dysfunctions (23%) and 13 permanent thyroid dysfunctions (12%). Progression-free survival was longer in patients with thyroid dysfunction (18.1 months) than in patients without thyroid dysfunction (3.9 months, P = 0.0085). In multivariate analysis, thyroid dysfunctions were not an independent predictive factor for progression-free survival. Patients with thyroid dysfunction had a longer overall survival (P = 0.0021), and thyroid dysfunctions were associated with a lower mortality risk (hazard ratio = 0.40; P = 0.005). Best response was positively associated with thyroid dysfunctions (P = 0.048). Thyroid dysfunctions induced by anti-PD-1 were not an independent predictive factor for progression-free survival in metastatic melanoma patients but seemed associated with a better response and increased overall survival.

International audience; Background With the development of precision oncology, Molecular Tumor Boards (MTB) are developing in many institutions. However, the implementation of MTB in routine clinical practice has still not been thoroughly studied. Material and methods Since the first drugs approved for targeted therapies, patient tumor samples were centralized to genomic testing platforms. In our institution, all tumor samples have been analyzed since 2014 by Next Generation Sequencing (NGS). In 2015, we established a regional MTB to discuss patient cases with 1 or more alterations identified by NGS, in genes different from those related to drug approval. We conducted a retrospective comparative analysis to study whether our MTB increased the prescriptions of Molecular Targeted Therapies (MTT) and the inclusions of patients in clinical trials with MTT, in comparison with patients with available NGS data but no MTB discussion. Results In 2014, 86 patients had UGA, but the results were not available to clinicians and not discussed in MTB. During the years 2015 and 2016, 113 patients with an UGA (unreferenced genomic alteration) were discussed in MTB. No patients with an UGA were included in 2014 in a clinical trial, versus 2 (2%) in 2015-2016. 13 patients with an UGA (12%) were treated in 2015-2016 with a MTT whereas in 2014, no patient (p = 0.001). Conclusions In this retrospective analysis, we showed that the association of large-scale genomic testing and MTB was feasible, and could increase the prescription of MTT. However, in routine clinical practice, the majority of patients with UGA still do not have access to MTT.

PURPOSE Emerging evidence suggests a correlation between the tumor mutational burden (TMB) and the response to programmed cell death-1 protein (PD-1) monotherapy across multiple cancer types. In skin cancers, as high TMB is mostly because of ultraviolet (UV) exposure, we hypothesized a correlation between the primary melanoma cutaneous location according to sun exposure and response to anti–PD-1 monotherapy. METHODS The aim of this study was to analyze, in advanced melanoma, the relationship between TMB, locations according to sun exposure, and response to PD-1 inhibitors. We conducted a prospective multicentric analysis, by sequencing the most recent metastatic sample before PD-1 inhibitors using FoundationOne assay. RESULTS One hundred two patients were included, with TMB available for 94 cases. In univariate and multivariate linear regression, TMB was significantly associated with sun-exposed areas of the primary melanoma location and with age (coefficients of the association with log-TMB: non-UV location, –1.05; chronic sun-exposed area, 1.12; P value for the location, < 10–5; age, 0.021 per year, P value for age, .002). Molecular UV signature present on the metastatic site was associated with higher TMB (P = .003). Melanomas bearing a high TMB had a higher probability of response to PD-1 inhibitors compared with melanomas with a low TMB, with a dose-dependent effect following an exponential curve and a negative odds ratio of 0.40 (95% CI, 0.20 to 0.72, P = .004) between log-TMB and 6-month progression. CONCLUSION Cumulative sun exposure related to skin location and molecular UV signature present on the metastatic site appear to be relevant biomarkers directly linked to TMB. Because TMB is not yet available to all for routine clinical use, the location of the primary melanoma in a sun-exposed area may play an important role in clinical decisions regarding therapeutic choice., The location of the primary melanoma in a sun-exposed area can help choosing first-line advanced melanoma treatment.

International audience; Actinic keratosis (AK) is a chronic skin condition that can be a precursor to cutaneous squamous cell carcinoma. AK can recur and patients are likely to undergo multiple treatments. It is important that AK lesions are managed appropriately, and that patients are involved in treatment decisions. Materials and methods The Supporting Professional Expertise in AK (SPEAK) program aims to facilitate this patient-centered care by identifying patient needs and aiding healthcare practitioners (HCPs) in selecting optimal treatment and communication strategies for different types of patients. Twenty-two dermato-oncologists with established expertise in the treatment of AK collaborated to describe commonly encountered psychosocial patient profiles, and to develop respective communication and treatment strategies. Results and conclusion Six patient profiles were defined based on different psychosocial characteristics and were used to develop appropriate management approaches. We provide a systematic way of identifying these patient profiles in clinical practice and we outline communication strategies tailored to the primary needs of each type of patient. In addition, we provide recommendations for potential field-treatments that may be best suited for each profile. The recommendations provided here may help improve the communication and relationship between patients and HCPs, resulting in higher treatment adherence and improved patient outcomes.

e21592 Background: While 10% of melanomas occur in a context suggesting hereditary predisposition, a clear molecular explanation has only been established for approximately 20% of families. In the course of clinical care, we identified a new CTNNA1 truncating germline mutation in a family affected by multiple early-onset melanomas. Methods: NGS and CGH-array were performed on the index case’s melanoma, followed by Sanger sequencing of the germline DNA of relatives. Immunochemistry (IHC) was employed to evaluate the level of αE-catenin (encoded by CTNNA1) in the family's samples. Stable CTNNA1 knockout human melanoma cell lines were generated to investigate the functional effects of CTNNA1 loss. Functional assays, including colony formation, 3-D tumor spheroid formation, wound healing, and transwell invasion were performed, as well as electron microscopy and RNAsequencing (RNAseq). CTNNA1 mutational status was determined in several databases and further sequencing of CTNNA1 in a DNA bank of families with multiple melanomas was done. Results: While the allele frequency in the index patient’s tumoral DNA was compatible with a germline mutation, the CTNNA1 F611fs*10 mutation was subsequently found cosegregating with individuals affected by melanoma in the family. CGH array on tumor DNA identified a segmental loss on chromosome 5, leading to a loss of heterozygosity of CTNNA1, resulting in a loss of αE-catenin observed by IHC. Clinically, the mean age of first melanoma diagnosis was 29,7 years (range: 18-56), 2 were metastatic, and the others were SSM (superficial spreading melanoma) in situ (n = 3) or Breslow index 0,56 mm (n = 1). Functional assays performed on CTNNA1 KO melanoma cell lines showed a loss of cell-to-cell adhesion phenotype, in accordance with the altered adherens junctions observed by electron microscopy, and the specific pathway enrichments observed by RNAseq. This specific phenotype could be rescued by transfection with a plasmid containing wild-type CTNNA1, as opposed to the CTNNA1 F611fs* plasmid. Germline CTNNA1 mutations are rare as none could be further identified in a DNA bank of 27 multiple melanoma families. In a database of 4743 melanomas somatically sequenced for CTNNA1, 131 of them had a CTNNA1 alteration (2,76%), with a median tumor mutational burden of 44 mut/MB of DNA (range from 0 to 451). Among them, 15 alterations were predicted to be inactivating, including 7 associated with a BRAF or NRAS activating mutation. Conclusions: Altogether, our results strongly support that CTNNA1 loss of function predisposes to melanoma formation characterized by a decreased cell adhesion. Since germline CTNNA1 alterations have already been implicated in lobular breast cancers and hereditary diffuse gastric cancers, CTNNA1 likely constitutes a tumor suppressor gene involved in familial melanoma, thus broadening the spectrum of syndromes associated with this gene.

Hereditary Diffuse Gastric Cancer (HDGC) is a cancer predisposing syndrome mainly caused by germline inactivating variants in CDH1, encoding E-cadherin. Early-onset diffuse gastric cancer (DGC) and/or invasive lobular breast cancer (LBC) are the main phenotypes in CDH1-associated HDGC. CTNNA1, encoding for α-E-catenin, and E-cadherin-partner in the adherens junction complex, has been recently classified as a HDGC predisposing gene. Nevertheless, little is known about CTNNA1 tumor spectrum in variant carriers and variant-type associated causality. Herein, we systematically reviewed the literature searching for CTNNA1 germline variants carriers, further categorized them according to HDGC clinical criteria (HDGC vs non-HDGC), collected phenotypes, classified variants molecularly and according to CDH1 ACMG/AMP guidelines and performed genotype-phenotype analysis. We found 41 families carrying CTNNA1 germline variants encompassing in total 105 probands and relatives. All probands from 13 HDGC families presented DGC and their average age of onset was 40 ± 17 years; 10/13 (77%) HDGC families carried a pathogenic (P) variant. Most probands from 28 non-HDGC families developed unspecified-BC, as well as most of their relatives; 4/28 (14%) carried a P variant, 16/28 (57%) carried a likely pathogenic (LP) variant, 7/28 (25%) carried variants of unknown significance (VUS) and 1/28 (4%) carried a likely benign variant. Regardless of clinical criteria, 97% (32/33) of probands and relatives from P variant-carrier families had DGC/unspecified-GC. In LP variant-carrier families, 82% (28/34) of probands and relatives had unspecified-BC. Only 2/105 individuals had LBC. A cluster of frameshift and nonsense variants was found in CTNNA1 last exon of non-HDGC families and classified as VUS. In conclusion, current available data confirms an association of CTNNA1 P variants with early-onset DGC, but not with LBC. We demonstrate that in ascertained cohorts, CTNNA1 P variants explain2% of HDGC families and support the use of ACMG/AMP CDH1 specific variant curation guidelines, while no specific guidelines are developed for CTNNA1 variant classification. Moreover, we demonstrated that truncating variants at the CTNNA1 NMD-incompetent last exon have limited deleteriousness, and that CTNNA1 LP variants have lower actionability than CDH1 LP variants. Current knowledge supports considering only CTNNA1 P variants as clinically actionable in HDGC carrying families.

Introduction En raison de l’oncogenese induite par les rayons ultraviolets, la charge mutationnelle tumorale est classiquement elevee dans les melanomes cutanes. Elevee, elle est un biomarqueur predictif de reponse aux anti-PD-1, mais une telle richesse mutationnelle peut au contraire faciliter l’emergence precoce de clones resistants sous therapies ciblees. Nous avons emis l’hypothese que la survie post immunotherapie vs therapies ciblees en 1e intention dans le melanome avance peut varier selon du profil de photo exposition du site de survenue du melanome primitif. Materiel et methodes Dans le cadre de Melbase, biobanque multicentrique francaise dediee au suivi prospectif des melanomes non resecables de stade III/IV, tous les patients atteints d’un melanome cutane primitif connu, ayant recu un traitement systemique de 1e intention par immunotherapie ou therapie ciblee entre 2013 et 2019 ont ete inclus. Les criteres de jugement etaient la survie sans progression (SSP) et la survie globale (SG). Resultats Neuf cent soixante treize patients ont recu une monotherapie anti-PD-1 (n = 466), anti-CTLA-4 (n = 143), l’association des deux (n = 118), dabrafenib + trametinib (n = 187) ou vemurafenib + cobimetinib (n = 59). Les caracteristiques des patients au debut du traitement etaient : sexe masculin (62 %), âge median 62 ans, BRAFwt (58 %), stade AJCC IV (84 %), metastases cerebrales (18 %), ECOG 0-1 (84 %) et LDH normaux (52 %). Le suivi median etait de 15,5 mois. Le melanome primitif etait localise en peau chroniquement photo-exposee (G1 : tete cou, n = 175), en peau exposee par intermittence (G2 : tronc, bras, jambes, n = 615), ou en zone non photo-exposee (G3 : paumes, plantes, n = 65). La mediane de SSP etait significativement meilleure pour le groupe G1 sous anti-PD-1 (8,7 mois vs 3,3 et 3,4 mois pour G2 et G3, respectivement) (p = 0,011), tandis que la SSP semblait meilleure pour le groupe G3 sous therapies ciblees (19,2 mois vs 8,1 et 6 mois pour G2 et G1) (p = 0,31), non significativite possiblement liee au faible effectif G3 traite par therapie ciblee (n = 8). La SSP ne differait pas significativement entre groupes sous ipilimumab. De meme, la mediane de SG etait significativement plus elevee pour le groupe G1 post anti PD-1 en 1e ligne (45,6 mois vs 31,6 et 21,4 mois pour G2 et G3) (p = 0,04), par opposition a la mediane de SG observee post therapies ciblees (19,5 mois vs 16,3 et 21,1 mois pour G1, G2 et G3 respectivement). Discussion Notre etude suggere que les anti-PD-1 en premiere intention sont particulierement recommandes en contexte de melanome primitif survenu en zone chroniquement exposee au soleil. En revanche, les patients dont le melanome provient d’une zone non-photo-exposee pourraient beneficier davantage d’une therapie ciblee de 1e intention lorsque cela est possible (presence de mutation BRAF), mais ce resultat reste a confirmer par des recherches ulterieures.

Introduction La crise sanitaire COVID-19 a bouleverse l’organisation du systeme de sante francais et international, par la soudainete de cette epidemie et des mesures ayant ete mises en place pour y faire face. L’objectif de cette etude est d’explorer l’influence de la crise sanitaire COVID-19 et particulierement de la reorganisation medicale qui en a resulte durant le 1er confinement sur un eventuel retard au diagnostic dans le melanome cutaneo-muqueux primitif, sur un bassin de population. Materiel et methodes Etude retrospective multicentrique, a partir des donnees de toutes les reunions de concertation pluridisciplinaire (RCP) d’oncodermatologie du departement de Loire-Atlantique. Comparaison, dans un bassin de population, des melanomes nouvellement diagnostiques durant une periode de 6 mois en 2020 (mars a aout) correspondant au 1er confinement en 2020 et les mois qui ont suivi (P20), aux melanomes diagnostiques sur les memes mois de l’annee precedente (mars a aout 2019), avant la crise sanitaire COVID-19: P19. Les donnees recueillies pour chaque cas etaient les suivantes : – pour le patient: âge et sexe ; –pour le melanome: sous-type histologique, indices de Breslow et de Clark, ulceration, stade AJCC, delai de prise en charge defini par le delai entre l’exerese initiale du melanome et le moment ou le patient est recu en RCP pour organisation d’une reprise chirurgicale ou prise en charge complementaire. Resultats Le nombre de melanomes nouvellement diagnostiques etait de 247 en P19 et 209 en P20. Le sex-ratio homme/femme etait de 1,1 en P19 et 1,2 en P20. La figure 1 illustre le nombre de cas par mois pour chacun des 6 mois en 2019 et 2020. Pendant la periode de confinement de 2020 (du 17 mars au 11 mai), 54 cas ont ete diagnostiques et 73 l’annee precedente sur la meme periode. L’indice de Breslow moyen en P19 etait de 1,83 mm et de 1,65 mm en P20 (p = 0,429). Le delai de prise en charge etait statistiquement significativement plus important en 2020 qu’en 2019 (delais de 33,36 jours versus 28,90 jours, p = 0,023). Discussion Sur ce bassin de population etudie, le nombre de melanomes diagnostiques a ete inferieur a celui observe l’annee precedente sur la meme periode et ce en particulier en avril-mai. Par contre, il ne semble pas y avoir de retard au diagnostic, en se basant sur le critere principal a savoir l’epaisseur au diagnostic. Il a ete montre de facon similaire dans une etude italienne une diminution franche du nombre de diagnostics de melanome en per confinement italien, avec decouverte d’un indice de Breslow moyen durant le confinement abaisse. Toutefois, une autre etude menee a Londres a montre des resultats differents avec notamment un taux de detection plus eleve durant le confinement. Il n’y a actuellement pas d’autre etude dans la litterature etudiant l’impact de la crise sanitaire COVID-19 sur le retard au diagnostic des melanomes en France.

Resume Introduction L’objectif de notre etude etait d’evaluer la diversite, ou l’homogeneite, des recommandations des RCP (Reunions de Concertation Pluridisciplinaire) dans la prise en charge des cancers cutanes de la face en France, et d’en analyser les determinants. Methodes Nous avons sollicite un panel de RCP d’onco-dermatologie et d’ORL et recueilli leurs recommandations pour trois cas cliniques : un carcinome epidermoide avec marge d’exerese incomplete chez un patient transplante renal (cas no 1), un carcinome basocellulaire localement avance (cas no 2) et un melanome de Dubreuilh in situ (cas no 3). Les reponses ont ete analysees de facon globale, puis selon deux sous-groupes definis par la presence ou non d’un dermatologue au sein de la RCP. L’impact de la composition de la RCP (selon la presence d’un dermatologue, d’un plasticien, d’un oncologue et d’un ORL) a ete evalue pour les principales propositions therapeutiques. Resultats Les avis des 45 RCP ayant repondu a l’enquete etaient contrastes pour les trois cas, sur des elements importants tels que l’indication de la reprise chirurgicale pour le cas no 1, la realisation d’un traitement alternatif a la chirurgie pour le cas no 2 ou les modalites de surveillance pour le cas no 3. Certaines propositions etaient associees a la presence d’un dermatologue au sein de la RCP, telles que la discussion de l’adaptation du traitement immunosuppresseur et le detail des marges chirurgicales a realiser pour le cas no 1, ou la surveillance simple et le detail des modalites de surveillance dans le cas no 3. Conclusion L’implication des dermatologues dans les RCP est importante a maintenir, de par leur expertise dans l’ensemble des domaines therapeutiques des cancers cutanes.

International audience; Purpose To determine performances of 2-deoxy-2-(18F)fluoro-d-glucose (18F-FDG) positron emission tomography (PET) to detect the development of permanent thyroid dysfunction (PTD), and to evaluate the prognostic value of early increased thyroid uptake in stage IV melanoma patients treated with anti-programmed death 1 (anti-PD-1) antibodies. Methods Twenty-nine patients were retrospectively enrolled. PTD was defined as symptomatic thyroid disorder requiring long-term specific treatment. On the first PET performed during follow-up, maximal standardized uptake value of the thyroid (SUVmax-Th) and SUVmax-Th/SUVmax-blood-pool ratio (Th/B) were measured. Areas under ROC curves (AUC) of these parameters for the diagnostic of PTD were compared. Cutoff values were defined to maximize the Youden's index. Survival analyses were performed according to the Kaplan-Meier method and compared using the log-rank method between patients with and without enhanced thyroid uptake according to cutoff values defined with the Hothorn and Lausen method. Results Four patients presented PTD. Median SUVmax-Th and Th/B were, respectively, 2.11 and 1.00. The median followup period was 21.7 months. AUC were 1.0 (CI 95% 0.88-1.0) for both parameters. Optimal cutoff values were, respectively, SUVmax-Th > 4.1 and Th/B > 2.0, both conferring sensitivities of 100% (CI 95% 40-100%) and specificities of 100% (CI 95% 86-100%). The median progression-free survival and overall survival were 11.3 months and 33.5 months, respectively. Using optimized cutoffs, there was no statistically significant difference of survival. Conclusion SUVmax-Th > 4.1 and Th/B > 2.0 provided perfect diagnostic performances to detect patients that developed PTD. No significant survival difference was found between patients with and without increased thyroid uptake.

Desmoplastic melanoma (DM) represents an infrequently occurring and distinct histologic pattern of melanomas, often lacking mutations in genes typically altered in conventional melanomas including BRAF , NRAS , and KIT . We aimed at better characterizing the genetic profile of this subgroup of melanomas to match patients with available therapies. Pathology reports were reviewed for 1,240 consecutive melanoma cases sequenced by comprehensive genomic profiling (CGP) using a hybrid-capture based next generation sequencing during the course of clinical care. The mutational profile of the 12 DM identified was compared with the remaining 1,228 melanomas examined. We report a median tumor mutational burden (TMB) of 77 mutations per megabase (mut/Mb) in DM, which was significantly greater than a median of 35 mut/Mb in non-DM. A UV DNA damage signature was detected in 10/12 (83%) DM. For a subset of patients with available clinical course, we report that 100% (5/5) had clinical benefit from treatment with PD-1 inhibitors as monotherapy. TMB and UV signature show significant promise as an approach to identify patients who are likely to benefit from PD-1 targeted immunotherapy.

Introduction L’avenement des therapies ciblees a considerablement ameliore le pronostic des patients atteints de melanome avance. Cependant la mise en route d’une therapie personnalisee est parfois retardee par la necessite de detecter une mutation ciblable dans la tumeur, telle que des mutations de BRAF. Ce delai peut s’allonger par des imperatifs incompressibles de demande de desarchivage, envoi, reception d’une biopsie anterieure, ou d’organisation d’une nouvelle biopsie avec temps de fixation, inclusion, extraction d’ADN. L’ADN tumoral circulant est une alternative connue et plus rapide, specifique mais peu sensible en cas de faible charge tumorale. Cependant il n’est pas rare d’observer des tumeurs ulcero-hemorragiques, dont l’ADN pourrait etre excrete en plus grande quantite en surface que dans la circulation generale. Nous rapportons les premiers cas d’identification de mutations somatiques a partir de simple solute de rincage d’exsudat tumoral. Materiel et methodes Trois patients (58–87 ans) atteints de melanomes stade IV, ont accepte la recherche de mutations somatiques dans le liquide de rincage de leur tumeur hemorragique, en parallele du sequencage tumoral classique. Du serum physiologique etait verse sur les tumeurs (10 mL) puis collecte en tube streck*, stabilisateur d’ADN libre circulant. L’ADN isole a ete analyse par sequencage nouvelle generation : panel de 20KB ciblant par technique d’amplification des oncogenes a visee theranostique. Resultats Dans les 3 solutes de rincage, des mutations identiques a celles identifiees par les biopsies classiques ont ete retrouvees : 2 mutations de BRAF et 1 mutation de KIT (frequences alleliques de 3 a 14 %). L’avantage de ce nouveau type de biopsie liquide de rincage est son confort pour le patient (rincage indolore et sans risque infectieux), son cout (pas d’anesthesie, pas de sutures), et sa rapidite de resultat et donc d’initiation de traitement adapte (1 semaine vs 3 semaines). Discussion Chez ces patients, la recherche d’ADN tumoral circulant dans le liquide de rincage s’est revelee concordante avec le resultat des biopsies. A notre connaissance, ce nouveau mode de biopsie liquide par rincage de tumeur ulceree n’a jamais ete decrit. En cas d’urgence therapeutique, il s’agit d’une option non invasive et abordable permettant l’introduction precoce d’un traitement adequat. Il est important de souligner le caractere localement avance et ulcere des melanomes etudies, potentialisant la presence d’ADN tumoral dans les echantillons preleves. Des etudes complementaires sur une plus grande cohorte permettraient de comparer la sensibilite de ce type de biopsie liquide de rincage par rapport aux biopsies liquides classiques par prise de sang. En cas de meilleure sensibilite, l’interet de cette nouvelle methode pourrait etre etendu a d’autres types de cancers avec metastases cutanees ulcerees.

International audience; BACKGROUND: BRAF and MEK inhibitors are approved for BRAF V600-mutated advanced melanoma, with response rates of up to 70%. Responses to targeted therapies have also been observed for diverse non-V600 BRAF alterations. Thus, sensitive, accurate, and broad detection of BRAF alterations is critical to match patients with available targeted therapies.MATERIALS AND METHODS: Pathology reports were reviewed for 385 consecutive melanoma cases with BRAF mutations or rearrangements identified using a hybrid capture-based next-generation sequencing comprehensive genomic profiling (CGP) assay during the course of clinical care.RESULTS: Records of prior BRAF molecular testing were available for 79 (21%) cases. Of cases with BRAF V600 mutations, 11/57 (19%) with available data were negative by prior BRAF testing. Prior negative BRAF results were also identified in 16/20 (80%) cases with non-V600 mutations, 2 of which harbored multiple BRAF alterations, and in 2/2 (100%) cases with activating BRAF fusions. Clinical outcomes for a subset of patients are presented.CONCLUSION: CGP identifies diverse activating BRAF alterations in a significant fraction of cases with prior negative testing. Given the proven clinical benefit of BRAF/MEK inhibitors in BRAF-mutated melanoma, CGP should be considered for patients with metastatic melanoma, particularly if other testing is negative.IMPLICATIONS FOR PRACTICE: Published guidelines for melanoma treatment recommend BRAF mutational analysis, but little guidance is provided as to selection criteria for testing methodologies, or as to clinical implications for non-V600 alterations. This study found that hybrid capture-based next-generation sequencing can detect BRAF alterations in samples from a significant fraction of patients with advanced melanoma with prior negative BRAF results. This study highlights the need for oncologists and pathologists to be critically aware of coverage and sensitivity limitations of various assays, particularly regarding non-V600E alterations, of which many are potentially targetable.

e21545 Background: The tumor mutational burden (TMB) is usually high in Cutaneous melanomas owing to ultraviolet radiation-induced oncogenesis. While a high TMB is a predictive biomarker of response to PD-1 inhibitors, it may be associated with the rise of resistant clones to targeted therapy over time. We hypothesized that the response pattern to immunotherapy and targeted therapy in advanced melanoma may vary depending on the sun-exposure profile of the site of primary melanoma. Methods: Patients were screened from MelBase, a French multicenter biobank dedicated to the prospective follow-up of unresectable stage III/IV melanoma. Within Melbase, all patients with a known cutaneous primary melanoma who received a first-line systemic treatment by immunotherapy or combined targeted therapy between January 2013 and November 2019 were included. Outcomes were progression-free survival (PFS ) and overall survival (OS). Results: 973 patients received either anti PD-1 monotherapy (n=466), anti CTLA-4 monotherapy (n=143), a combination of both (n=118), dabrafenib plus trametinib (n=187) or vemurafenib plus cobimetinib (n=59). Patients’ characteristics at treatment initiation were: male gender (62%), median age of 62 years old, BRAF WT (58%), AJCC stage IV (84%), brain metastases (18%), ECOG 0-1 (84%) and normal LDH (52%). Median follow-up was 15.5 months. The primary melanoma was located on chronically sun-exposed skin in 175 patients (G1: head neck), on intermittently sun-exposed skin in 615 patients (G2: trunk, arms, legs), and on sun-protected areas in 65 patients (G3: palms, soles, nails). Median PFS was significantly higher in G1 under anti PD-1 treatment (8,7 months vs 3,3 and 3,4 months for G2 and G3, respectively) (p=0.011), (19,2 months vs 8,1 and 6 months for G2 and G1) (p=0. although it is worthwhile to note that the number of G3 patients treated with targeted therapy was relatively low (n=8). PFS did not significantly differ between all groups under ipilimumab. Similarly, median OS was significantly higher in G1 receiving first-line anti PD-1 treatment (45,6 months vs 31,6 and 21,4 months for G2 and G3) (p=0.04), while OS was higher in G3 under targeted therapy (21,1 months vs 16,3 and 19,5 months for G2 and G1) (p=0.97). Conclusions: Our study suggests that first-line immunotherapy with anti PD-1 is particularly recommended for melanomas originating from chronically sun-exposed areas. On the other hand, melanomas originating from sun-protected areas may benefit more from first-line targeted therapy when possible (presence of BRAF mutation), but this finding needs to be confirmed by further research.

Immune checkpoint inhibitors and targeted therapies have profoundly altered the management of several cancers over the past decade. Metastatic melanoma has been at the forefront of these changes. We provide here a nationwide overview and an assessment of changes in survival in France. We included 10,936 patients receiving a systemic treatment for metastatic cutaneous melanoma between 2010 and 2017 using the French National Health Insurance database (Système National des Données de Santé). Over the study period, there was a doubling of the number of new patients receiving a systemic treatment. Cytotoxic chemotherapy was progressively replaced by targeted therapy and immune checkpoint inhibitors. Patients having initiated a first-line treatment since June 2015 gained 46% overall survival compared with those initiating treatment before 2012. Overall survival at 24 months rose from 21% to 44%. We provide real-world evidence for the improvement of overall survival in the past decade among patients with metastatic melanoma. Although the characteristics of the patients treated can vary across periods, this type of exhaustive real-world data provides evidence from broader populations than those included in clinical trials.

Introduction Le pronostic du melanome metastatique a ete considerablement ameliore par la mise a disposition de l’immunotherapie, ciblant notamment programmed cell death 1 (PD-1) depuis juin 2015. Cependant, plusieurs etudes recentes suggerent une perte d’efficacite de l’immunotherapie quand son initiation est immediatement precedee d’une antibiotherapie. Une dysbiose intestinale induite par l’antibiotherapie limiterait l’effet de l’immunotherapie sur les cellules tumorales. Notre objectif etait d’estimer l’effet de l’antibiotherapie dans le mois qui precede l’initiation d’un anti-PD-1, sur l’efficacite de l’immunotherapie, chez des patients atteints de melanome metastatique. Materiel et methodes Nous avons reconstruit a partir de la base de donnees de l’Assurance-Maladie (Systeme National des Donnees de Sante) une cohorte comprenant tous les patients ayant recu un anti-PD-1 en traitement de premiere ligne d’un melanome metastatique en France entre 2015 et 2017. Nous avons estime l’effet de l’antibiotherapie sur la survie globale et la duree de l’immunotherapie par un modele de Cox. Les potentiels facteurs de confusion concernant les caracteristiques des patients (âge, sexe, comorbidites), du melanome (sites de metastases, radiotherapie ou metastasectomie recentes), ont ensuite ete pris en compte par une analyse multivariee. La survie globale et la duree de traitement par anti-PD-1 ont ete representes en fonction de la prise ou non d’antibiotique par une courbe de Kaplan–Meier. Des analyses de sensibilite ont fait varier la fenetre d’exposition a l’antibiotherapie, et le type d’antibiotherapie recue. Resultats Parmi les 2605 patients ayant ete traites par anti-PD-1 en premiere ligne, 336 (12,9 %) ont recu un antibiotique dans le mois qui precedait. La survie etait similaire chez les patients ayant recu ou non un antibiotique dans le mois qui precedait, en analyse univariee (hazard ratio [HR], 0,97, intervalle de confiance a 95 % [IC95 %], [0,81–1,18]), ou multivariee (HR = 0,91 [0,75–1,10]). La duree de traitement par anti-PD-1 etait egalement similaire dans les 2 groupes, en analyse univariee (HR = 1,01 [0,87–1,16]), ou multivariee (HR = 0,99 [0,86–1,15]). Lorsque l’antibiotherapie etait recue entre 2 mois avant et 1 mois apres l’initiation de l’anti-PD-1, ou lorsque seule la prise d’amoxicilline-acide clavulanique etait consideree, la survie et la duree de traitement n’etaient pas non plus modifiees. Discussion Ces resultats, obtenus a partir de donnees exhaustives nationales et sans perdu de vue, contredisent les etudes precedentes, d’effectif plus faible. Ils doivent inciter a la prudence avant de remettre en question la prescription d’antibiotique precedant l’initiation d’un anti-PD-1 quand ils sont necessaires, voire de retarder l’initiation de l’immunotherapie.

Introduction Cette etude avait pour objectif principal d’evaluer la valeur pronostique des dysthyroidies chez les patients traites par anti-PD-1 pour un melanome metastatique. L’objectif secondaire etait d’evaluer l’impact pronostique des effets secondaires auto-immuns, et en particulier du vitiligo. Materiel et methodes Au total 110 patients avec un melanome de stade IV ou de stade III inoperable, traites par anticorps anti-PD-1 seuls ou en association aux anticorps anti-CTLA-4 au centre Eugene Marquis entre janvier 2015 et decembre 2017, ont ete inclus dans cette etude retrospective. Le suivi median etait de 32,8 mois. Les dysthyroidies permanentes (DP) ont ete distinguees des dysthyroidies transitoires (DT). Le critere principal etait la survie sans progression (SSP). Les criteres secondaires etaient la meilleure reponse observee et la survie globale (SG). Les courbes de survie ont ete comparees par un test du log rank et un modele de Cox a permis d’ajuster les caracteristiques des patients et des melanomes. Resultats Trente-huit (35 %) dysthyroidies ete observees au cours du suivi dont 25 DT (23 %) et 13 DP (12 %). La SSP etait plus longue chez les patients avec une dysthyroidies (18,1 mois versus 3,9 mois ; p = 0,0085). En analyse multivariee, les dysthyroidies n’etaient pas un facteur pronostique independant pour une meilleure SSP. Les patients avec une dysthyroidie avaient une survie globale plus longue (p = 0,0021), un risque de mortalite plus faible (hazard ratio [HR] = 0,40 ; p = 0,005) et une meilleure reponse observee (p = 0,048). Les toxicites auto-immunes n’etaient pas independamment associees avec une meilleure SSP ou SG. Seul le vitiligo avait un impact pronostique independant sur la SSP (HR = 0,42) et la SG (HR = 0,22). Discussion Les dysthyroidies sous anti-PD-1 chez les patients avec un melanome metastatique n’etaient pas un facteur pronostique independant d’une meilleure SSP mais semblaient associes a une meilleure reponse et a un risque plus faible de deces. Il n’y avait pas d’impact pronostique independant des toxicites auto-immunes sur la SSP et la SG. Seul le vitiligo, comme cela a deja ete demontre dans la litterature, etait independamment associe a une meilleure SSP et SG.

International audience; Tumour angiogenesis is defined by an anarchic vasculature and irregularities in alignment of endothelial cells. These structural abnormalities could explain the variability in distribution of nanomedicines in various tumour models. Then, the main goal of this study was to compare and to characterize the tumour vascular structure in different mouse models of melanoma tumours (B16F10 and SK-Mel-28) and in human melanomas from different patients. Tumours were obtained by subcutaneous injection of 10 B16F10 and 3.10 SK-Mel-28 melanoma cells in C57BL/6 and nude mice, respectively. Tumour growth was evaluated weekly, while vasculature was analysed through fluorescent labelling via CD31 and desmin. Significant differences in tumour growth and mice survival were evidenced between the two melanoma models. A fast evolution of tumours was observed for B16F10 melanoma, reaching a tumour size of 100 mm in 7 days compared to SK-Mel-28 which needed 21 days to reach the same volumes. Important differences in vascularization were exposed between the melanoma models, characterized by a significant enhancement of vascular density and a significant lumen size for mice melanoma models compared to human. Immunostaining revealed irregularities in endothelium structure for both melanoma models, but structural differences of vasculature were observed, characterized by a stronger expression of desmin in SK-Mel-28 tumours. While human melanoma mainly develops capillaries, structural irregularities are also observed on the samples of this tumour model. Our study revealed an impact of cell type and tumour progression on the structural vasculature of melanoma, which could impact the distribution of drugs in the tumour environment.

Introduction Environ 7 % des melanomes surviennent dans un contexte evocateur d’une predisposition hereditaire, or seuls 20 % d’entre eux ont une cause moleculaire clairement identifiee a ce jour. Au decours de l’analyse somatique d’un melanome, il arrive de detecter des mutations constitutionnelles. Materiel et methodes Le test NGS FoundationOne® permettant le sequencage de 315 genes a ete propose a un patient de 23 ans atteint de melanome stade III dans un contexte de multiples antecedents familiaux de melanomes (mere et 2 sœurs, l’une decedee de son melanome a 33 ans). Une CGH-array a ete realisee a partir d’ADN tumoral. L’immunohistochimie (IHC) des proteines impliquees dans la voie Wnt/β-catenine a ete realisee sur le melanome du patient et une serie de melanomes controles. Les caracteristiques cliniques de la famille ont ete recueillies. Resultats Le test FoundationOne® sur ADN tumoral a mis en evidence une mutation BRAFV600E avec une frequence allelique (FA) de 3 % associee a une mutation CTNNA1 F611fs*10 (gene suppresseur de tumeur codant pour l’α-catenine). Cette mutation, responsable d’un decalage du cadre de lecture induisant un codon stop, est trouvee avec une FA de 41 %. Cette discordance de FA pouvait faire evoquer une mutation constitutionnelle de CTNNA1, confirmee dans le sang de sa mere et sa sœur. La CGH sur l’ADN tumoral a identifie une perte segmentaire du chromosome 5 en 5q31.2. Cette perte bi-allelique de CTNNA1 se traduit par une perte d’expression de CTNNA1 en IHC dans le melanome du patient. Sur le plan clinique, les 7 melanomes familiaux ont ete operes a un âge moyen de 29 ans (18–56), 2 etaient avances (Breslow 6,7 mm/metastatique d’emblee), et les autres etaient des SSM in situ (n = 4) ou de Breslow 0,56 mm (n = 1). Le patient index presente une agenesie dentaire, une fente labiopalatine et un goitre multinodulaire. Enfin, le sequencage haut debit FoundationOne® sur une serie de 4889 melanomes successifs a retrouve CTNNA1 mute dans 145 cas (3 %). Les mutations perte de fonction sont frequemment associees a des mutations activatrices de BRAF ou NRAS. Discussion CTNNA1 est un frein de la voie Wnt/β-catenine. In vitro, sa perte de fonction favorise l’evolution metastatique par hyperproliferation et perte d’adhesion cellulaire. Des mutations germinales CTNNA1 ont ete mises en cause dans les cancers du sein lobulaires et les cancers gastriques diffus familiaux. Nous decrivons ici la 1ere mutation CTNNA1 dans un contexte de melanomes familiaux. Conclusion CTNNA1 est un bon candidat pour expliquer les multiples melanomes de cette famille, avec selon le modele des 2 hits de Knudson, une mutation constitutionnelle tronquante de CTNNA1 et une perte somatique d’un segment du chromosome 5. Outre des perspectives de prevention/depistage precoce du melanome chez les porteurs de mutation CTNNA1, une meilleure connaissance de cette voie oncogenique pourrait aider a concevoir de nouvelles strategies de combinaison de therapies ciblees dans le traitement du melanome.

Introduction L’ipilimumab (ipi) a ete le premier inhibiteur de points de controle immunologiques developpe dans le traitement du melanome metastatique. Aujourd’hui derembourse en France en monotherapie, la question de sa place dans l’arsenal therapeutique du melanome stade IV se pose, notamment apres echec des anti-PD1. Materiel et methodes Nous presentons le cas d’un patient traite pour un melanome dependant a l’ipi. Observations Un patient de 50 ans etait suivi pour un melanome du dos de type « Deep Penetrating Naevus », NRAS mute. En 2017, l’evolution multi-metastatique faisait debuter une 1ere ligne de traitement systemique par pembrolizumab. Devant une progression tumorale et une alteration de l’etat general apres 7 cures, un sequencage NGS de 315 genes a ete realise, mettant en evidence une charge mutationelle intermediaire et une perte d’APC. En relais du pembrolizumab, le patient a recu 4 cures d’ipi, permettant une reponse quasi complete de toutes les cibles. Trois mois apres l’arret du traitement etait constatee une rechute avec metastases multiples. Quatre cures d’ipi ont alors ete reprises, cette fois en association avec le nivolumab, permettant a 3 mois une reponse viscerale quasi complete, sauf pour les metastases cerebrales traitees par radiotherapie. La tolerance du traitement etait bonne. Malgre un relais par nivolumab, 3 mois apres la derniere cure d’ipi on constatait pour la 2e fois une rechute multi-metastatique, et cette fois encore la reprise de l’ipi, associe au Nivolumab permettait une reponse quasi complete (a l’exception des metastases cerebrales). Le patient etait alors traite par ipi seul a partir de janvier 2019. Le patient est decede subitement a son domicile en avril 2019, alors qu’il se portait bien, probablement sur hemorragie cerebrale. Discussion Nous presentons le 1er cas de patient dependant a l’ipi. Sous anti-PD1 seul (en 1re intention et par la suite en relais de l’ipi) on observait irremediablement une progression metastatique, cela pouvant etre explique en partie par la charge mutationnelle intermediaire. Mais surtout, la perte APC explique aussi probablement la dependance du patient a l’anti-CTLA4 : la perte d’APC, frequemment retrouvee dans les melanomes de type DPN, active la voie Wnt/beta-catenine. Or, il a ete montre sur des cellules de melanome que l’activation de cette voie entraine une sur-expression de CTLA-4 a la surface cellulaire. Effectivement, le marquage CTLA-4 en IHC sur les cellules tumorales de notre patient est revenu particulierement positif en comparaison avec une serie de 10 melanomes controles. Conclusion Cela suggere une action potentiellement directe de l’immunotherapie sur la tumeur quand celle-ci exprime CTLA4 a sa surface. Des marquages sur de plus grandes series pourraient permettre d’evaluer cette expression proteique comme marqueur de reponse a l’ipi.

Introduction Le pronostic du melanome metastatique a beaucoup evolue ces dernieres annees avec le developpement des therapies ciblees et des inhibiteurs de check-points. Nous rapportons une reponse clinique remarquable aux anti-MEK chez une patiente presentant une fusion RAF1. Observations Il s’agit d’une patiente de 65 ans presentant un melanome metastatique avec des localisations secondaires ganglionnaires, sous-cutanees et ileales. Les mutations BRAF, NRAS et KIT etaient negatives et un essai therapeutique ouvert de phase 3 associant un anti-PD-L1 (atezoluzimab 840 mg j1–j15) et un anti-MEK (cobimetinib, 60 mg par jour j1–j21) chez les patients non mutes BRAF etait propose en premiere ligne. A j10 du debut du traitement, une regression quasi complete des nodules sous-cutanes etait constatee. A j15, la patiente etait hospitalisee pour une pneumopathie interstitielle de grade 4 attribuee a l’atezoluzimab d’evolution favorable mais entrainant la sortie de l’essai therapeutique. Elle etait ensuite traitee en 2e et 3e ligne par anti-PD1 et par chimiotherapie avec une progression clinique notable. Devant l’absence d’alternative therapeutique, un screening moleculaire large FoundationOne etait realise. Une fusion de RAF1 etait mise en evidence. Un traitement par anti-MEK (trametinib) a demi-dose etait debute sous surveillance stricte notamment sur le plan pulmonaire. La reponse clinique et scanographique apres deux mois de traitement etait spectaculaire avec une remission partielle (−35 % selon les criteres RECIST) de sa maladie avec un recul de 3 mois. La tolerance du traitement etait excellente sans recidive de la pneumopathie interstitielle. Discussion La reponse clinique rapide des cibles sous-cutanees sous l’association anti-PD-L1 et anti-MEK nous faisait deja suspecter une sensibilite aux anti-MEK. Le programme Experience FoundationOne® (partenariat CHU-Roche®) propose une analyse par sequencage nouvelle generation (NGS) grâce a un panel de 315 genes et de 28 introns, ceci afin d’etablir un profil genomique de la tumeur. Ce large panel peut etre d’un grand interet pour la recherche de nouvelles cibles therapeutiques notamment en cas d’echec des traitements standards. La fusion du gene RAF1 (ou CRAF) est un evenement rare aboutissant a une hyperactivite de la proteine kinase Raf1. Il en resulte une activation constitutionnelle de la voie des MAP-kinases. Sur le plan moleculaire, les fusions impliquant le gene BRAF comme celles impliquant le gene CRAF aboutissent a une activation de la voie des MAP-kinases et constituent donc des cibles therapeutiques. Conclusion Nous decrivons le troisieme cas de fusion du gene RAF1 permettant une efficacite surprenante des anti-MEK sur le melanome metastatique. La voie des MAP-kinases est une cible therapeutique de predilection dans le traitement des melanomes. Le developpement de panels larges de screening moleculaire permet d’augmenter l’arsenal therapeutique et la survie des patients atteints de melanome metastatique.

Background BRAF genomic alterations (GA) occur in multiple tumor types and BRAF/MEK targeted therapies are approved in melanoma and NSCLC. Diverse mechanisms of AR to these therapies have been proposed but have not been comprehensively assessed. Methods Hybrid-capture based comprehensive genomic profiling (CGP) was performed on FFPE (n = 228,629) or blood-based cell free DNA (cfDNA, n = 15,069) samples for 222,952 patients (pts). Tumor mutational burden (TMB) was determined on 0.8-1.1 Mbp of sequenced DNA. Samples without evidence of tumor DNA or known to have not received RAF/MEK inhibitors were excluded. Paired samples were collected >60 days apart (median 523, range 71-5571). Results Paired samples with BRAF V600E (64%) or other activating BRAF GA (36%) were available for 154 pts with NSCLC (20%), melanoma (19%), CRC (15%) myeloma (8.4%) glioma (7.1%) or other (30%) cancers. Acquired GA previously described preclinically or clinically including in BRAF, KRAS, NRAS, MEK1, PIK3CA, PTEN, MET, and CCND1 occurred in 34 cases (Table). 56 additional cases had reportable acquired GA in other genes (eg. STK11, NF1). Median TMB was 4.0 vs 5.2 mut/Mb in the first vs second sample (p = 0.23). In 12% of cases (9 tissue, 9 cfDNA) a BRAF GA was not detected in the second sample. Most AR mechanisms (MET amp, KRAS mut, secondary BRAF GA) were tumor agnostic, but PIK3CA and PTEN GA were enriched in brain samples and absent in CRC, and NRAS mut were exclusive to melanoma (Table). Treatment status was available for a subset of cases. Notably V600E CRC, NSCLC and melanoma each had acquired MET amp post-dabrafenib + trametinib, and a V600E myeloma had acquired MEK C121S post-trametinib + vemurafenib. Additional clinical data will be presented. Table: 1878PD . Potential AR mechanism No. cases# AR subtypes Disease Histologies Associated Primary BRAF GA Biopsy location * KRAS mut 7 G12D (2), G12R, G12V, G13D, Q61H, K117N CRC (2), NSCLC (2), cholangiocarcinoma, multiple myeloma, CLL V600E (6), G466A omentum (2), liver NRAS mut 4 G12C, G13R, G13R/Q61H, Q61H/K melanoma (4) V600E (2), V600R, G469A brain (1), lymph node (1), soft tissue (1) NRAS amp 1 amp estimated copies: 41 NSCLC V600E pericardial fluid Secondary BRAF GA 10 N-terminal deletion exons 2-8 (6), duplications exons 10-18, L505H, N581I/D594G, amp estimated copies: 6 NSCLC (4), CRC (2), melanoma (2), multiple myeloma, pancreatic V600E (9), G466A liver (3), lymph node (2), lung, abdominal wall, brain MEK1 mut 1 C121S multiple myeloma V600E NA PIK3CA mut 5 H1047R (2), G1049R, R88Q, S405F glioma (3), NSCLC, thyroid V600E (3), N486_T491>K, R506_K507insVLR brain (4), lung PTEN GA 5 E7fs * , R130 * , G129R, splice site 165-1G>A, loss melanoma (2), glioma, NSCLC, UP neuroendocrine V600E, V600K, R506_K507insVLR, KHDRBS2-BRAF fusion brain (2), abdomen, soft tissue CCND1 amp 2 amp estimated copies: 9, 10 NSCLC, thyroid V600E, G464V brain, pleural fluid MET amp 4 amp estimated copies: 12, 14, 15, 56 NSCLC, CRC, melanoma, UP adenocarcinoma V600E (4) lymph node, colon, brain, liver * Indicated for tissue samples only (NA= not applicable); #5 cases had AR alterations in multiple genes included here; NSCLC: non-small cell lung cancer, CRC: colorectal carcinoma; CLL: chronic lymphocytic leukemia; UP: unknown primary; AR: acquired resistance; mut: mutation; amp: amplification. Conclusions Novel and previously observed potential AR alterations in paired BRAF altered clinical samples were detected using CGP. Most AR mechanisms appeared independent of tumor type and biopsy site. Additional clinical studies to explore effective treatments for these AR subsets are needed. Legal entity responsible for the study The authors. Funding Foundation Medicine. Disclosure F. Pietrantonio: Advisory / Consultancy: Roche; Advisory / Consultancy: Amgen; Advisory / Consultancy: Eli-Lily; Advisory / Consultancy: Bayer; Advisory / Consultancy: Sanofi; Advisory / Consultancy: Servier; Advisory / Consultancy: Merck Serono. J. Lee: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine; Shareholder / Stockholder / Stock options: Roche. L. Boussemart: Advisory / Consultancy: Novartis; Advisory / Consultancy: Pierre Fabre. G. Srkalovic: Speaker Bureau / Expert testimony: Foundation Medicine. R. Madison: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine; Shareholder / Stockholder / Stock options: Roche. J.S. Ross: Leadership role, Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine; Shareholder / Stockholder / Stock options: Roche. V.A. Miller: Leadership role, Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine; Shareholder / Stockholder / Stock options: Roche; Advisory / Consultancy: Revolution Medicines. B.M. Alexander: Leadership role, Full / Part-time employment: Foundation Medicine; Shareholder / Stockholder / Stock options: Roche. S.M. Ali: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine; Shareholder / Stockholder / Stock options: Roche. A.B. Schrock: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine; Shareholder / Stockholder / Stock options: Roche. All other authors have declared no conflicts of interest.

International audience; Recent advances in targeted anticancer therapies have substantially improved the prognosis of several cancers. Such targeted therapies are not, however, free of side effects, and these side effects are clearly distinct from those induced by classical cytotoxic chemotherapies. This is likely so because targeted therapies are designed to interfere with specific oncogenic signaling pathways rather than to inhibit cell proliferation in general. In fact, interference with specific signaling pathways may lead to effects that mimic those associated with genetic disorders due to alterations in the corresponding signaling pathways. Here, we compare the clinical effects of treatment with BRAF inhibitors with those of genetic RASopathies and find a striking overlap between the inhibitor-induced, iatrogenic dermatoses with the genodermatoses seen in patients with corresponding congenital RASopathies. We hope that such comparisons lead to a better understanding of the side effects of targeted therapies.

Introduction L’objectif de notre etude etait d’evaluer la diversite, ou l’homogeneite des recommandations des RCP dans la prise en charge des cancers cutanes de la face en France, et d’en analyser les determinants. Materiel et methodes Nous avons sollicite un panel de RCP d’onco-dermatologie et d’ORL et recueilli leurs recommandations pour 3 cas cliniques : un carcinome epidermoide chez un patient transplante renal en marge d’exerese incomplete (cas n°1), un carcinome basocellulaire localement avance (cas n°2), et un melanome de Dubreuilh in situ (cas n°3). Les reponses ont ete analysees de facon globale, puis selon 2 sous-groupes definis par la presence ou non d’un dermatologue au sein de la RCP. L’impact de la composition de la RCP (selon la presence d’un dermatologue, d’un plasticien, d’un oncologue et d’un ORL) a ete evalue pour les principales propositions therapeutiques. Resultats Les avis des 45 RCP ayant repondu a l’enquete etaient contrastes pour les trois cas, sur des elements importants tels que l’indication de la reprise chirurgicale pour le cas n°1, la realisation d’un traitement alternatif a la chirurgie pour le cas n°2 ou les modalites de surveillance pour le cas n°3. Certaines propositions etaient associees a la presence d’un dermatologue au sein de la RCP, telles que la discussion de l’adaptation du traitement immunosuppresseur et le detail des marges chirurgicales a realiser pour le cas n°1, ou la surveillance simple et le detail des modalites de surveillance dans le cas n°3. Conclusion L’implication des dermatologues dans les RCP est importante a maintenir, de par son expertise dans l’ensemble des domaines therapeutiques des cancers cutanes.

Introduction Le xeroderma pigmentosum (XP) est une maladie genetique autosomique recessive rare touchant 1 cas/1 million de naissances en Europe. Elle est liee a un defaut du systeme de reparation de l’ADN « nucleotide excision repair », post-exposition UV, responsable d’une photosensibilite precoce avec survenue de cancers cutanes multiples des l’enfance. Plusieurs groupes de complementation existent avec des phenotypes variables. Le XP de type A (XPA) est a l’origine de la forme la plus severe avec anomalies neurologiques et deces dans l’enfance. Les cas de XPA ont ete decrits surtout au Japon et chez des patients originaires d’Afrique du Nord a ce jour, avec des mutations tronquantes ou perte de fonction essentiellement. Nous rapportons le 1er cas de XPA francais sur phenotype relativement peu severe et examen neurologique normal. Materiel et methodes Un exome medical (5500 genes OMIM) a ete realise par sequencage nouvelle generation (NGS) sur l’ADN constitutionnel (extrait des globules blancs sanguins) d’une patiente au phenotype evocateur de XP mais pour laquelle les genes de XP classiquement en cause en France (XPC, XPV) etaient non mutes. Observation Une patiente de 49 ans, d’origine francaise et de phototype III, a ete multi-operee depuis l’adolescence pour exerese de plus de 30 carcinomes cutanes (basocellulaires ou epidermoides). Parmi ses antecedents, on notait une photosensibilite des l’enfance, avec survenue de bulles des mains et des pieds post-exposition solaire et un erytheme actinique intense et facile. Cliniquement, il etait retrouve en plus des carcinomes, de nombreuses lentigines et une poikilodermie. L’enquete genetique a mis en evidence une consanguinite entre les 2 grand-meres de la patiente. Le sequencage de l’exome a permis de mettre en evidence une mutation homozygote de XPA c.731G > A, p.H244R, dans l’exon 6. Discussion XPA est un groupe de complementation dont les alterations sont peu frequentes en Europe. Les phenotypes observes chez les patients atteints sont severes avec deces avant l’âge de 10 ans et anomalies neurologiques notables. La mutation homozygote XPA H244R est la premiere mutation d’XPA identifiee en France a l’origine d’un phenotype peu severe. Cette mutation a deja ete retrouvee a l’etat heterozygote en association avec une autre mutation chez une patiente japonaise de 2 ans, « XP8LO » (De Weerd Kastelein et al., Mut Res 1976, Satokata et al., Mut Res 1992). Cette mutation n’a jamais ete rapportee a l’etat homozygote dans la litterature jusqu’a present. La presence d’une dizaine de carcinomes epidermoides et d’une photosensibilite chez le pere de la patiente, porteur heterozygote de la mutation p.H244R souleve, la question de la prevalence a l’etat heterozygote de cette mutation au sein de la population francaise.

Purpose: The emergence of skin tumors in patients treated with sorafenib or with more recent BRAF inhibitors is an intriguing and potentially serious event. We carried out a clinical, pathologic, and molecular study of skin lesions occurring in patients receiving sorafenib. Experimental Design: Thirty-one skin lesions from patients receiving sorafenib were characterized clinically and pathologically. DNA extracted from the lesions was screened for mutation hot spots of HRAS, NRAS, KiRAS, TP53, EGFR, BRAF, AKT1, PI3KCA, TGFBR1, and PTEN. Biological effect of sorafenib was studied in vivo in normal skin specimen and in vitro on cultured keratinocytes. Results: We observed a continuous spectrum of lesions: from benign to more inflammatory and proliferative lesions, all seemingly initiated in the hair follicles. Eight oncogenic HRAS, TGFBR1, and TP53 mutations were found in 2 benign lesions, 3 keratoacanthomas (KA) and 3 KA-like squamous cell carcinoma (SCC). Six of them correspond to the typical UV signature. Treatment with sorafenib led to an increased keratinocyte proliferation and a tendency toward increased mitogen-activated protein kinase (MAPK) pathway activation in normal skin. Sorafenib induced BRAF–CRAF dimerization in cultured keratinocytes and activated CRAF with a dose-dependent effect on MAP-kinase pathway activation and on keratinocyte proliferation. Conclusion: Sorafenib induces keratinocyte proliferation in vivo and a time- and dose-dependent activation of the MAP kinase pathway in vitro. It is associated with a spectrum of lesions ranging from benign follicular cystic lesions to KA-like SCC. Additional and potentially preexisting somatic genetic events, like UV-induced mutations, might influence the evolution of benign lesions to more proliferative and malignant tumors. Clin Cancer Res; 18(1); 263–72. ©2011 AACR.