Combined Nivolumab and Ipilimumab in Octogenarian and Nonagenarian Melanoma Patients

Data regarding elderly melanoma patients treated with anti-PD-1 or anti-CTLA-4 antibodies are in favor of tolerability outcomes that are similar to those of younger counterparts. However, there are very few studies focusing on elderly patients receiving nivolumab combined with ipilimumab (NIVO + IPI). Here, we ask what are the current prescribing patterns of NIVO + IPI in the very elderly population and analyze the tolerance profile. This French multicenter retrospective study was conducted on 60 melanoma patients aged 80 years and older treated with NIVO + IPI between January 2011 and June 2022. The mean age at first NIVO + IPI administration was 83.7 years (range: 79.3-93.3 years). Fifty-five patients (92%) were in good general condition and lived at home. Two dosing regimens were used: NIVO 1 mg/kg + IPI 3 mg/kg Q3W (NIVO1 + IPI3) in 27 patients (45%) and NIVO 3 mg/kg + IPI 1 mg/kg Q3W (NIVO3 + IPI1) in 33 patients (55%). NIVO + IPI was a first-line treatment in 39 patients (65%). The global prevalence of immune-related adverse events was 63% (38/60), with 27% (16/60) being of grade 3 or higher. Grade ≥ 3 adverse events were less frequent in patients treated with NIVO3 + IPI1 compared with those treated with NIVO1 + IPI3 (12% versus 44%, p = 0.04). In conclusion, the prescribing patterns of NIVO + IPI in very elderly patients are heterogeneous in terms of the dosing regimen and line of treatment. The safety profile of NIVO + IPI is reassuring; whether or not the low-dose regimen NIVO3 + IPI1 should be preferred over NIVO1 + IPI3 in patients aged 80 years or older remains an open question.

Intratumoral dendritic cell-CD4+ T helper cell niches enable CD8+ T cell differentiation following PD-1 blockade in hepatocellular carcinoma

Despite no apparent defects in T cell priming and recruitment to tumors, a large subset of T cell rich tumors fail to respond to immune checkpoint blockade (ICB). We leveraged a neoadjuvant anti-PD-1 trial in patients with hepatocellular carcinoma (HCC), as well as additional samples collected from patients treated off-label, to explore correlates of response to ICB within T cell-rich tumors. We show that ICB response correlated with the clonal expansion of intratumoral CXCL13+CH25H+IL-21+PD-1+CD4+ T helper cells ("CXCL13+ TH") and Granzyme K+ PD-1+ effector-like CD8+ T cells, whereas terminally exhausted CD39hiTOXhiPD-1hiCD8+ T cells dominated in nonresponders. CD4+ and CD8+ T cell clones that expanded post-treatment were found in pretreatment biopsies. Notably, PD-1+TCF-1+ (Progenitor-exhausted) CD8+ T cells shared clones mainly with effector-like cells in responders or terminally exhausted cells in nonresponders, suggesting that local CD8+ T cell differentiation occurs upon ICB. We found that these Progenitor CD8+ T cells interact with CXCL13+ TH within cellular triads around dendritic cells enriched in maturation and regulatory molecules, or "mregDC". These results suggest that discrete intratumoral niches that include mregDC and CXCL13+ TH control the differentiation of tumor-specific Progenitor exhasuted CD8+ T cells following ICB.

Treatment of Recurrent Melanoma Following Adjuvant Therapy

In the era of effective therapies in melanoma, notably the widespread use of two types of adjuvant treatments: anti-PD-1 immunotherapies and therapies targeting the mitogen-activated protein kinase pathway, for BRAF-mutant patients, an important question arises about how to treat these patients in case of recurrent melanoma following adjuvant therapy. Prospective data are lacking in this area and might be difficult to obtain due to the constant progress being made in the field. Therefore, we reviewed available data suggesting that the initial adjuvant treatment received and the following events provide information about the biology of the disease and the probability of response to following systemic treatments. Thus, in case of relapse during or just after adjuvant anti-PD-1, immune resistance is probable, an anti-PD-1 monotherapy rechallenge has a low likelihood of clinical benefit, and escalation with a combination of immunotherapies should be given priority. In case of relapse during treatment with BRAF plus MEK inhibitors, there may be a risk of lower efficacy of immunotherapy than in naïve patients since this relapse attests not only to a resistance to BRAF-MEK inhibition, but also the introduction of immunotherapy to rescue a progression on targeted therapy. In case of relapse long after adjuvant treatment cessation, whatever the treatment received, no conclusion can be drawn about the efficacy of these drugs, and these patients can be treated like naïve patients. Thus, a combination of anti-PD-1 and anti-CTLA4 is probably the best solution, and the following line can be BRAF-MEK inhibitors in BRAF-mutated patients. Finally, in case of recurrent melanoma following adjuvant therapy, given the promising upcoming strategies, inclusion in a clinical trial should be offered as frequently as possible.

Single-cell analysis of human non-small cell lung cancer lesions refines tumor classification and patient stratification

Immunotherapy is a mainstay of non-small cell lung cancer (NSCLC) management. While tumor mutational burden (TMB) correlates with response to immunotherapy, little is known about the relationship between the baseline immune response and tumor genotype. Using single-cell RNA sequencing, we profiled 361,929 cells from 35 early-stage NSCLC lesions. We identified a cellular module consisting of PDCD1⁺CXCL13⁺ activated T cells, IgG⁺ plasma cells, and SPP1⁺ macrophages, referred to as the lung cancer activation module (LCAM^hi). We confirmed LCAM^hi enrichment in multiple NSCLC cohorts, and paired CITE-seq established an antibody panel to identify LCAM^hi lesions. LCAM presence was found to be independent of overall immune cell content and correlated with TMB, cancer testis antigens, and TP53 mutations. High baseline LCAM scores correlated with enhanced NSCLC response to immunotherapy even in patients with above median TMB, suggesting that immune cell composition, while correlated with TMB, may be a nonredundant biomarker of response to immunotherapy.

685 Characterization of molecular and spatial diversity of macrophages in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) has a dismal prognosis, and though checkpoint blocking antibodies have significantly improved patient outcome, many patients remain left out, highlighting the need to identify additional immune target to enhance therapeutic immunity. Macrophages (MF) are an abundant and heterogeneous population in the tumor microenvironment (TME), and are associated with a poor prognosis in multiple tumor types, including HCC, however, their molecular and functional diversity is still poorly understood.

Methods

We analyzed the molecular and spatial organization patterns of immune cells within the TME and adjacent tissue of 26 resected HCC lesions using single-cell RNA sequencing and multiplex immunohistochemistry (IHC).

Results

We found that Kupffer cells, the self-renewing tissue-resident macrophages in liver tissue, are lacking from the TME, which is dominated by monocyte-derived macrophages. ScRNAseq followed by high-resolution clustering identified distinct MF molecular programs within the monocyte-derived macrophage compartment. One MF subset expressed a shared signature with monocytes including FCN1, S100A8 and T cell activation genes like CXCL9 and IL32. Conversely, one subset of MF expressed FOLR2, SEPP1 and genes of the complement (C1Qs), a program shared with KC in the adjacent tissue, and include another intratumoral subset enriched for the expression of TREM2 and GPNMB. Guided by these results, we are developing an IHC antibody panel that allows to visualize distinct MF localization in the TME. Intratumoral MF interface with, and potentially regulate, the T cell compartment within the TME. We are analyzing HCC tumor lesions in our treatment-naïve cohort and in patients treated with neoadjuvant anti-PD-1 therapy (NCT03916627) to study co-localization and direct interaction of MF and T cells using physically-interacting cell sequencing (PICseq). This analysis enables us to identify MF with direct cell-cell contact with T cells, and our preliminary analysis demonstrates an enrichment in MF with an immunosuppressive phenotype. We are also using spatial transcriptomic to map molecular programs of MF in the TME, that we will corroborated with additional patients.

Conclusions

Taken together, our data provide a new understanding of intratumoral MF diversity and highlight the presence of specific immunoregulatory MF programs unique to tumor lesions, with subsets of these MF found to be directly interacting with T cells, potentially modulating anti-tumor responsiveness. Our analysis of resected tumor from anti-PD-1 treated patients, will allow us to correlate MF programs, and direct T cell interaction, with clinical response, and will inform therapeutic trials targeting specific MF populations so as to improve clinical efficacy of cancer immunotherapy.

Trial Registration

NCT03916627

Ethics Approval

Samples of tumor and non-involved liver were obtained from surgical specimens of patients undergoing resection at Mount Sinai Hospital (New York, NY) after obtaining informed consent in accordance with a protocol reviewed and approved by the Institutional Review Board at the Icahn School of Medicine at Mount Sinai (RUTH Human Subjects Electronic Submission System 18–00407 and 20–04150) and in collaboration with the Biorepository and Department of Pathology.

[Minimal change nephropathy and IgA deposits associated with a Sezary syndrome]

INTRODUCTION

The Sézary syndrome (SS) is an aggressive form of cutaneous T-cell lymphoma (CTCL) requiring a rapid diagnosis due to its poor prognosis.

CASE REPORT

We report the first case of an eighty-nine-year-old woman who presented with concomitant Sezary syndrome and anasarca, revealing a nephrotic syndrome caused by a minimal change nephropathy associated with immunoglobulin A (IgA) deposits. Scarce literature described rare cases associating these two entities (nephrotic syndrome and nephropathy). However, the nephrotic syndrome was delayed from disease onset, secondary to immunosuppressive treatment of SS, or due to the weaning of SS therapy. Thus, the direct link between the glomerular lesion and the cutaneous lymphoma was difficult to establish. However, the synchronous occurrence of both SS and glomerulopathy in our patient, along with Sezary cells in both urines (urinary cytology) and biopsy, and resolution of nephropathy after treatment of SS, support the likely attributability of SS in glomerulopathy.

CONCLUSION

Practitioners must acknowledge the possible occurrence of glomerular involvement in SS.

Surgery of small bowel melanoma metastases in the era of efficient medical therapies: a retrospective cohort study

Surgery of small bowel melanoma metastases has to be reconsidered in the era of targeted treatments and immunotherapy. To retrospectively assess context and outcomes of small bowel melanoma metastases resections. All consecutive melanoma patients who underwent resection of small bowel metastases between 2011 and 2017, in a single referral center, were retrospectively analyzed through melanoma-specific survival (MSS). A total of 20 patients were included with a 47.8 months median follow-up. Before small bowel surgery, eight patients (40%) were asymptomatic while seven had anemia and five patients had abdominal pain. All resections were decided on tumor boards except for three surgeries performed in the emergency setting. In the whole cohort, MSS was 89.5 months with 50% of patients alive at the study endpoint. We classified surgical indications in three groups: (1) surgery as a pivotal treatment for mono- or oligo-metastases limited to the small bowel (n = 6); (2) salvage surgery for symptomatic patients in order to preserve their chances to switch to an active line of medical treatment (n = 8); and (3) surgery of small bowel dissociated metastatic progression for patients otherwise controlled (n = 6), aiming at keeping patients with the same treatment or active follow-up. In these three situations, the objective of surgery was usually met, and most patients had a long median MSS after surgery: 70.3 months, 89.5 months and 72.4 months, respectively. Although medical treatments have dramatically improved survival in metastatic melanoma, surgical control of life-threatening localization like small bowel metastases is often a condition for long survival.

Abstract 64: Characterization of molecular and spatial diversity of macrophages in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has a dismal prognosis, and though checkpoint blocking antibodies have significantly improved patient outcome, many patients remain left out highlighting the need to identify additional immune target to enhance therapeutic immunity. Macrophages (MΦ) are an abundant and heterogeneous population in the tumor microenvironment (TME), and are associated with a poor prognosis in multiple tumor types, including HCC, however, their molecular and functional diversity is still poorly understood. We analyzed the molecular and spatial organization patterns of immune cells within the TME and adjacent tissue of 23 resected HCC lesions using single-cell RNA sequencing and multiplex immunohistochemistry (IHC). Strikingly, we found that Kupffer cells (KC), the self-renewing tissue-resident macrophages in liver tissue, are lacking from the TME, which is dominated by monocyte-derived macrophages. ScRNAseq followed by high-resolution clustering identified distinct MΦ molecular programs within the monocyte-derived macrophage compartment. One MΦ subset expressed a shared signature with monocytes including FCN1 and S100A8 in addition to T cell activation genes like CXCL9 and IL32. Conversely, one subset of MΦ expressed FOLR2, SEPP1 and genes of the complement (C1Qs), a program shared with KC in the adjacent uninvolved tissue, and include another intratumoral subset enriched for the expression of TREM2 and GPNMB. Guided by these results, we are developing an IHC antibody panel that allows to visualize distinct MΦ localization in the TME. Intratumoral MΦ interface with, and potentially regulate, the T cell compartment within the TME. We are analyzing HCC tumor lesions in our treatment-naïve cohort and in patients treated with neoadjuvant anti-PD-1 therapy (NCT03916627) to study direct interaction of MΦ and T cells using an innovative technology of physically-interacting cell sequencing (PICseq). This analysis enables us to identify MΦ with direct cell-cell contact with T cells, and our preliminary analysis demonstrates an enrichment in MΦ with a highly immunosuppressive phenotype. We are also using PICseq to map the molecular program of MΦ that are interacting with T cells and that we will corroborated with additional patients. Taken together, our data provide a new understanding of intratumoral MΦ diversity and highlight the presence of specific immunoregulatory MΦ programs unique to tumor lesions, with subsets of these MΦ found to be directly interacting with T cells, potentially modulating anti-tumor responsiveness. Our analysis of resected tumor from anti-PD-1 treated patients, will allow us to correlate MΦ programs, and direct T cell interaction, with clinical response, and will inform therapeutic trials targeting specific MΦ populations so as to improve clinical efficacy of cancer immunotherapy.

Citation Format: Pauline Hamon, Assaf Magen, Merav Cohen, Alexandra Tabachnikova, Christie Chang, Mark Buckup, Leanna Troncoso, Zhen Zhao, Joel Kim, Amir Giladi, Nausicaa Malissen, Fiona Desland, Jessica Le Berichel, Ido Amit, Ephraim Kenigsberg, Myron Schwartz, Thomas Marron, Miriam Merad. Characterization of molecular and spatial diversity of macrophages in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 64.

Identification of an Immature Subset of PMN-MDSC Correlated to Response to Checkpoint Inhibitor Therapy in Patients with Metastatic Melanoma

PMN-MDSCs support tumor progression and resistance to ICI therapy through their suppressive functions but their heterogeneity limits their use as biomarkers in cancer. Our aim was to investigate the phenotypic and functional subsets of PMN-MDSCs to identify biomarkers of response to ICI therapy. We isolated low-density CD15⁺ PMNs from patients with metastatic melanoma and assessed their immune-suppressive capacities. Expression of CD10 and CD16 was used to identify mature and immature subsets and correlate them to inhibition of T cell proliferation or direct cytotoxicity. Frequencies of the PMN-MDSCs subsets were next correlated to the radiological response of 36 patients receiving ICI therapy. Mature activated cells constituted the major population of PMN-MDSCs. They were found in a higher proportion in the pre-treatment blood of patients non responders to ICI. A subset of immature cells characterized by intermediate levels of CD10 and CD16, the absence of expression of SIRPα and a strong direct cytotoxicity to T cells was increased in patients responding to ICI. The paradoxical expansion of such cells during ICI therapy suggests a role of PMNs in the inflammatory events associated to efficient ICI therapy and the usefulness of their monitoring in patients care.

Treatment strategies and safety of rechallenge in the setting of immune checkpoint inhibitors-related myositis: A national multicenter study

OBJECTIVES

The occurrence of immune-related myositis (irM) is increasing, yet there are no therapeutic guidelines. We sought to analyze the current therapeutic strategies of irM and evaluate the outcomes of immune checkpoint inhibitors (ICI) rechallenge.

METHODS

We conducted a nationwide retrospective study between April 2018 and March 2020 including irM without myocardial involvement. Depending on the presence of cutaneous signs or unusual histopathological features, patients were classified into two groups: typical or atypical irM. Therapeutic strategies were analyzed in both groups. The modalities and outcomes of ICI rechallenge were reviewed.

RESULTS

Among the 20 patients, 16 presented typical irM. Regardless of severity, most typical irM were treated with steroid monotherapy (n = 14/16) and all had a complete response within ≤ 3 weeks. The efficacy of oral steroids for non-severe typical irM (n = 10) was the same with low-dose (≤ 0.5 mg/kg/day) or high-dose (1 mg/kg/day). Severe typical irM were successfully treated with intravenous methylprednisolone. Atypical irM (n = 4) had a less favorable evolution, including one irM-related death, and required heavy immunosuppression. ICI were safely reintroduced in 9 patients presenting a moderate (n = 6) or a severe (n = 3) irM.

CONCLUSION

Our data highlight that steroid monotherapy is an effective treatment for typical irM, either with prednisone or with intravenous methylprednisone pulses depending on the severity. The identification of unusual features is important in determining the initial therapeutic strategy. The outcomes of rechallenged patients are in favor of a safe reintroduction of ICI following symptom resolution and CK normalization in moderate and severe forms of irM.

Which adjuvant treatment for patients with BRAFV600-mutant cutaneous melanoma?

Treatment of patients with melanoma has considerably improved over the past decade and more recently with adjuvant therapies for patients with American Joint Committee on Cancer (AJCC) stage III (loco-regional metastases) or IV (distant metastases) totally resected melanoma, in order to prevent recurrence. In the adjuvant setting, two options are available to patients with BRAF^V600-mutant AJCC stage III totally resected melanoma: anti-PD-1 blockers (nivolumab or pembrolizumab) or BRAF plus MEK inhibitors (dabrafenib plus trametinib). In the absence of comparative studies, it is difficult to determine which of these options is best. Our aim was to review published studies focusing on the management of patients with BRAF^V600-mutant melanoma in the adjuvant setting. We also reviewed the main clinical trials of BRAF plus MEK inhibitors and immunotherapy in advanced (i.e. unresectable metastatic) BRAF-mutant melanoma in an attempt to identify results potentially affecting the management of patients on adjuvants. More adverse events are observed with targeted therapy, but all resolve rapidly upon drug discontinuation, whereas with immune checkpoint blockers some adverse events may persist. New therapeutic strategies are emerging, notably neoadjuvant therapies for stage III patients and adjuvant therapies for stage II patients; the place of the adjuvant strategy amidst all these options will soon be re-evaluated. The choice of adjuvant treatment could influence the choice of subsequent treatments in neo-adjuvant or metastatic settings. This review will lead clinicians to a better understanding of the different adjuvant treatments available for patients with totally resected AJCC stage III and IV BRAF^V600-mutant melanoma before considering subsequent treatment strategies.

Cross-cultural adaptation into French and validation of the SCAR-Q questionnaire

PURPOSE

Most questionnaires designed to evaluate patient-reported outcomes regarding scarring are available in English. The objective was to generate a validated French version of the SCAR-Q questionnaire.

METHODS

The SCAR-Q questionnaire (including Appearance, Symptom and Psychological impact scales) was translated into French using a translation-back-translation process in accordance with international guidelines (ISPOR and WHO). For validation, two hundred patients consulting in our tertiary center completed the questionnaire. We tested scale reliability (Cronbach's α), floor/ceiling effects and item redundancy (inter-item correlations). Structural validity was tested using confirmatory factor analysis (CFA) with the robust weighted least squares (WLSMV) estimator and Delta parameterization. Model fit was examined using the root mean square error of approximation (RMSEA), the comparative fit index (CFI) and the Tucker-Lewis index (TLI). Correlations between scales and scale repeatability were tested (Spearman coefficient, Intra-class-coefficient).

RESULTS

Four steps were required to obtain a translation consistent with the original version. Two hundred patients completed the questionnaire for validation. Internal consistency analysis found Cronbach's alphas > 0.7 for all scales (0.90 < α < 0.97). No floor or ceiling effect was found for all items (max = 85%). A ceiling effect was observed for all scales. Appearance and psychosocial impact scale items showed redundancy, with many inter-item correlations above 0.7. The CFA of the original structure displayed a reasonable fit, with RMSEA = 0.065, CFI = 0.974 and TLI = 0.972. Scales were positively correlated (0.45 <  ρ < 0.65; p < 0.001). Test-retest intra-class correlation coefficients ranged from 0.94 to 0.99 for all scales.

CONCLUSION

A French version of the SCAR-Q questionnaire is validated, ready for use.

Early Phase of Primary Melanoma Growth from the Patient Point of view: A Prospective Cross Sectional Study on Melanoma over 1 mm in Thickness

Most melanomas are diagnosed by the patients themselves or by their partners or relatives; they alone can describe its history. We designed a prospective cross-sectional study to describe patients’ perception of morphology, growth pattern and kinetics of their primary melanoma over 1 mm in thickness before resection. Patients were interviewed with a questionnaire, a grid representing 9 possible scenarios of melanoma growth, and a set of 87 photographs of potential aspects of melanomas and precursors. Most patients were able to describe the growth of their melanoma and select pictures representative of its successive aspects before resection. Among 453 patients, 60% reported a preexisting lesion present for years. Growth pattern scenarios concurred with tumor kinetics but with no statistical difference between nodular and superficial spreading subtypes. These subjective patient-reported indicators about melanoma growth over time could dynamically complement its objective pathological analysis otherwise static at a single time point.

HVEM has a broader expression than PD-L1 and constitutes a negative prognostic marker and potential treatment target for melanoma

HVEM (Herpes Virus Entry Mediator) engagement of BTLA (B and T Lymphocyte Attenuator) triggers inhibitory signals in T cells and could play a role in evading antitumor immunity. Here, HVEM expression levels in melanoma metastases were analyzed by immunohistochemistry, correlated with overall survival (OS) in 116 patients, and validated by TCGA transcriptomic data. Coincident expression of HVEM and its ligand BTLA was studied in tumor cells and tumor-infiltrating lymphocytes (TILs) by flow cytometry (n = 21) and immunofluorescence (n = 5). Candidate genes controlling HVEM expression in melanoma were defined by bioinformatics studies and validated by siRNA gene silencing. We found that in patients with AJCC stage III and IV melanoma, OS was poorer in those with high HVEM expression on melanoma cells, than in those with a low expression, by immunohistochemistry (p = .0160) or TCGA transcriptomics (p = .0282). We showed a coincident expression of HVEM at the surface of melanoma cells and of BTLA on TILs. HVEM was more widely expressed than PD-L1 in melanoma cells. From a mechanistic perspective, in contrast to PDL1, HVEM expression did not correlate with an IFNγ signature but with an aggressive gene signature. Interestingly, this signature contained MITF, a key player in melanoma biology, whose expression correlated strongly with HVEM. Finally, siRNA gene silencing validated MITF control of HVEM expression. In conclusion, HVEM expression seems to be a prognosis marker and targeting this axis by checkpoint-inhibitors may be of interest in metastatic melanoma.

Metastatic Melanoma: Recent Therapeutic Progress and Future Perspectives

The prognosis of patients with metastatic melanoma has dramatically improved in recent years with the introduction of two new therapeutic strategies. BRAF and MEK inhibitors are small molecules that are able to block the mitogen-activated protein kinase (MAPK) pathway, which is constitutively activated by recurrent BRAF V600 mutations in 45% of melanoma patients. These agents were shown to provide a rapid and strong response but are often limited by a high rate of secondary resistance. Monoclonal antibodies against the immune checkpoints cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and programmed death 1 (PD-1) can restore an efficient and durable anti-tumor immunity, even following treatment discontinuation. Anti-PD-1 antibodies were shown to prolong survival of metastatic melanoma patients and a real cure seems to be obtainable in some patients. Many more therapies are currently under investigation, given that 50% of patients still do not have long-term benefits from approved treatments. The main goal is to avoid or circumvent primary or secondary immune resistance to anti-PD-1 therapy not only by targeting other players in the tumor microenvironment but also by optimizing treatment sequencing and combining anti-PD-1 with other treatments, especially with BRAF and MEK inhibitors. The unexpected major successes of immunotherapies in melanoma have opened the way for the development of these treatments in other cancers. In this review, we describe the different available treatments, their toxicities, and the key components of our decisional algorithms, and give an overview of what we expect to be the near future of melanoma treatment.

[Chordoma cutis, an unusual clinical presentation of a rare neoplasm: Chordoma]

Chordoma cutis represents an unusual clinical presentation of a rare neoplasm. The involvement of skin or sub-cutaneous soft tissues can be the consequence of local infiltration or metastasis; the latter may occur several years following the initial diagnosis of chordoma and therefore, may pose a diagnosis challenge when the clinical history of the patient is unknown. The clinical forms, morphology, immuno-histochemical profile and the main differential diagnoses of chordoma cutis are presented here through an anatomoclinical case.

A novel anti-CD146 antibody specifically targets cancer cells by internalizing the molecule

CD146 is an adhesion molecule present on many tumors (melanoma, kidney, pancreas, breast, ...). In addition, it has been shown to be expressed on vascular endothelial and smooth muscle cells. Generating an antibody able to specifically recognize CD146 in cancer cells (designated as tumor CD146), but not in normal cells, would thus be of major interest for targeting tumor CD146 without affecting the vascular system.

We thus generated antibodies against the extracellular domain of the molecule produced in cancer cells and selected an antibody that specifically recognizes tumor CD146. This antibody (TsCD146 mAb) was able to detect CD146-positive tumors in human biopsies and in vivo, by PET imaging, in a murine xenograft model. In addition, TsCD146 mAb antibody was able to specifically detect CD146-positive cancer microparticles in the plasma of patients. TsCD146 mAb displayed also therapeutic effects since it was able to reduce the growth of human CD146-positive cancer cells xenografted in nude mice. This effect was due to a decrease in the proliferation and an increase in the apoptosis of CD146-positive cancer cells after TsCD146-mediated internalization of the cell surface CD146.

Thus, TsCD146 mAb could be of major interest for diagnostic and therapeutic strategies against CD146-positive tumors in a context of personalized medicine.

Survival of melanoma patients treated with targeted therapy and immunotherapy after systematic upfront control of brain metastases by radiosurgery

BACKGROUND

Targeted therapy (TT) and immunotherapies (ITs) have dramatically improved survival in metastatic melanoma (MM). However, their efficacy on brain metastasis (BM) remains limited and poorly documented.

PATIENTS AND METHODS

Retrospective cohort of consecutive MM patients (pts) with BMs, all systematically upfront treated by Gamma-Knife (GK) at first BM and retreated in case of new BMs, from 2010 to 2015 at the time when ipilimumab BRAF ± MEK inhibitors and anti-PD1 were introduced in practice. Survival after 1st GK (OS_GK1) according to prognostic factors and treatment.

RESULTS

Among 179 consecutive pts treated by GK, 109 received IT and/or TT after the 1st GK. Median OS_GK1 was 10.95 months and 1- and 2-year survival rates were 49.5% and 27.4%, respectively, versus a median overall survival (OS) of 2.29 months (p < .001) in those who did not receive IT or TT. In pts who initially had a single BM, median OS and 1- and 2-year survival rates were 14.46 months, 66.7% and 43.4%, respectively; in pts with 2-3 BMs: 8.85 months, 46.4% and 31%, respectively; in pts with >3 BMs: 7.25 months, 37.2% and 11.9%, respectively. Multivariate analysis for OS_GK1 confirmed that IT and TT were significantly and highly protective. Best OS_GK1 was observed in BRAF-wild-type pts receiving anti-PD1 or in BRAF-mutated pts receiving BRAF-inhibitors and anti-PD1 (12.26 and 14.82 months, respectively).

CONCLUSION

In real-life MM pts with BMs, a strategy aiming at controlling BM with GK together with TT and/or TT seems to achieve unprecedented survival rates.

Risk factors of fast growing melanomas in a French prospective cohort

e21042

Background: Rate of growth (ROG) of the primary tumor is a known prognostic factor in melanoma (MM). Fast growing melanomas (FGMM) could account for an important part of the thick tumors which still exist despite earlier and earlier detection. Methods: All patients referred for a primary mm to two French Dermatology Department from the period 2012-2016 were prospectively enrolled in an observational case control study. ROG was calculated as the ratio of Breslow thickness to time to mm development according to patient, following a well-established process. FGMM were defined as those with a ROG > 0.5 mm/month and MMs with a ROG ≤05mm/month were used as controls. Differences in epidemiological, clinical and pathological features were evaluated with univariate and multivariate analysis. Results: 464 patients were enrolled. 149 mm (32.1%) were FGMM. Factors associated with FGMM in univariate analysis were age > 70 years (p = 0.006), tumor location (p = 0.032), histological subtype (p = 0.021), median thickness (p < 0.001), ulceration (p < 0.001), high mitotic rate ( > 1/mm2 )(p = 0.002), sentinel node involvement (p = 0.008), hair color at the age of 20 (p = 0.011), lower NSAIDS consumption (p = 0.012) and lower number of sunburns (p = 0.002). Age > 70 years (OR 1.88 95%CI 1.19-2.98, p = 0.007), ulceration (OR 3.70 95%CI 2.05-6.61) p < 0.001), sentinel node involvement (OR 1.93 95%CI 1.01-3.69 p = 0.046), regression (OR 0.37 95%CI 0.15-0.94) p = 0.037) and NSAIDS exposure (OR 0.29 95%CI 0.11-0.78, p = 0.014) remained associated with FGMM in multivariate analysis. OS and PFS were significantly lower in the FGMM group (HR 1.98 (95%CI 1.11-3.54, p = 0.02) and HR 1.79 (95%CI 1.17-2.73, p = 0.007), respectively). Conclusions: Fast growth characterizes a subset of primary mm which are intrinsically more aggressive and have different risk factors than other MM, namely more frequent in the elderly and with no association with skin type, nevus count or sun exposure. Association with ulceration could reflect a specific immune context. Negative association with NSAIDS exposure warrants more investigation, since it may have therapeutic implications.

Glycemic disorders in melanoma patients treated with anti-PD1

9525

Background: Anti-PD1 are now the backbone of immunotherapy (IT) of metastatic melanoma (MM). Although they are overall well- tolerated, a number of severe immune-related adverse events (IRAE) have been described, among which type 1 diabetes. We observed 3 cases of fulminant diabetes (FD) in our center, and also had the impression that diabetics patients became more difficult to manage when receiving anti-PD1. Methods: Retrospective analysis of blood glucose samples collected before, during and after anti-PD1 treatment (trt ) in all mm patients (pts) receiving anti-PD1 in our department over a 36-month period. Study of FD cases observed. Results: A total of 163 pts were treated with 1920 cures of anti-PD1 including 27 treated within clinical trials. Anti-PD1 was the 1st line of IT in 70% of cases. As a whole, 1470 glycaemia were available. There was no significant difference between the median pre and post-trt glycaemia (5.37 +/-1.6 vs 5.6 +/-1.3 mmol/L (p = 0.033)). In the 28 pts with a type I (n = 0) or II (n = 28) diabetes prior to trt, there was very slight drift toward an increase of glycaemia along with the successive trt infusions (+0.05mmol/L/Cure, p = 0.004 with linear regression tendency test) .Three pts (1.84%) developed a FD revealed by a severe episode of ketosis with acute polyuria polydipsia, hyperglycaemia until 50mmol/L and weight loss. Two additional cases of FD were observed in pts treated within clinical trial comparing anti-PD1 with anti-CTLA4 in adjuvant and metastatic situation (imputability of anti-PD1 likely but uncertain until unblinding). None of these pts had any glucose increase in weeks prior to FD diagnosis. Four out of 5 FD cases had an HLA group at risk for type 1 diabetes development (HLA DRB3/4), a rare group in general population (1%). Conclusions: We could not document any systematic tendency to glycemic disorder in mm pts treated by anti-PD1. In diabetic pts prior to trt, a slight drift toward increase of glycaemia may be explained by other interfering factors (diet, metastatic disease itself, corticosteroids, anxiety etc). FD is not exceptional (2% of patients in our series) and does not seem to be announced by any minor preliminary glycemic disorder. Despite apparently stochastic onset, FD may be associated with HLA DRB3/4 subgroup.

HVEM: A novel cosignaling molecule of major interest in melanoma

e14591

Background: Herpes Virus Entry Mediator (HVEM) is a member of the TNF superfamily, its ligation of the immunoglobulin family member B-lymphocyte and T-lymphocyte attenuator (BTLA) activates inhibitory signaling in T-cells and could play a role in evading host anti-tumor immunity. Ectopic overexpression of HVEM is associated with poor survival in some solid tumors. Our objectives were: -to evaluate HVEM expression in melanoma (MM) -to explore potential link of its overexpression with clinical outcomes -to understand the mechanisms by which HVEM was ectopically expressed in MM, and how HVEM-BTLA may play a role in MM. Methods: HVEM expression was analyzed by IHC in formalin-fixed samples of mm metastases and was correlated with OS in 130 patients. To better understand how HVEM could interfere with prognosis, relation of HVEM with its ligand BTLA was studied in the tumor and tumor microenvironment on 15 fresh metastases by flow cytometry after tumor dissociation. Bioinformatic studies based on TCGA and CCLE data combined to targeting of candidate genes by siRNA were used to investigate HVEM regulation on MM. Results: Patients with high HVEM expression on mm cells in their metastases have a significantly (p = 0.0142) poorer overall survival than those with a low expression. TCGA transcriptomic data support these results. From the mechanistic point of view, we could show that 1-HVEM expressed at the tumor cell surface interacts with BTLA expressed by tumor-infiltrated lymphocytes. 2-HVEM expression is neither linked to the mm mutational status nor inducible by IFN 3-Genes co-regulated with HVEM are associated with an aggressive gene signature 4- HVEM strongly correlate with MITF expression, MITF binds HVEM promoter, and its downregulation by siRNA results in a decrease in HVEM expression. Conclusions: A high expression of HVEM by mm metastases seems to be a pejorative prognostic marker. HVEM-BTLA interaction is a co-signaling system similar to the PD1-PDL1 one, but seem to be constitutive rather than inducible. HVEM and its co-regulated genes may constitute a signature of aggressiveness associated to MITF. High HVEM expression on mm cells may dampen anti-tumor immune responses, making HVEM and BTLA potential new targets for “checkpoint blockade” therapy.

Safety and results of anti-PD1 combined with radiosurgery for the treatment of melanoma brain metastases

9552

Background: Anti-PD1 are now pivotal in the treatment of metastatic melanoma (MM). Some concerns have emerged regarding the risk/benefit ratio of their combination with stereotactic radiosurgery. Methods: Retrospective assessment of the interaction between Gamma-Knife radiosurgery (GKRS) and anti-PD1 in terms of toxicity and OS in mm patients (pts) with BM. Patients were included if they were under anti-PD1 (PRE) at time of GKRS, or if they had started anti-PD1 concomitantly with GKRS (CO), or had received anti-PD1 within 3 months after GKRS (POST). Results: Among 47 pts who received GKRS and anti-PD1 during their disease course, 35 fulfilled PRE or CO or POST criteria (anti PD1 1st line therapy in 10 pts and 2d or more in 25 pts). One pt died before radiological evaluation. GKRS targeted a single BM in 10 pts and multiple BMs in 24 (max 19 BMs). Out of the 128 BMs treated, 6 cases of increase of preexisting edema (4.7%) and 8 hemorrhages (6.25%) occurred in 12 pts, but only 5 events (5%) were regarded as Adverse Radiation effects (ARE), being symptomatic in 3 pts (8% of pts). One BM had to be resected because of the occurrence of a symptomatic hemorrhage with hemiparesis 9 month after treatment. Median follow- up from GKRS was 13.7 mths. Median overall survival (OS) from GKRS and 1st BM were 14.8 and 26.5 mths respectively, with 6 and 12 mths 0S rates from GKRS of 65.7% and 57%, respectively. Local failure was observed in 5 pt. Median time to new BM was 12.6 mths. There was no significant difference in outcomes in pts, depending on PRE, CO and POST conditions. Conclusions: In this series, the largest to date of pts with BMs treated by GKRS and anti-PD1,ARE were within the expected range and survival rates appear promising. Given the natural propensity of MM-BMs for bleeding and edema our data do not support an increased risk with the combination of GKRS and anti-PD1. Regarding the timing between anti-PD1 administration and GKRS our data do not support a higher efficacy or higher toxicity among the 3 following potential mechanisms: immuno- sensitization to radiation (PRE), immuno-radio direct synergy (CO) or radiosensitization to immunotherapy (POST).

Long-term treatment of cutaneous manifestations of tuberous sclerosis complex with topical 1% sirolimus cream: A prospective study of 25 patients

BACKGROUND

Data on long-term topical sirolimus treatment of the cutaneous manifestations of tuberous sclerosis complex are rare.

OBJECTIVE

To evaluate the long-term benefit and tolerance of topical 1% sirolimus in tuberous sclerosis complex.

METHODS

In this 18-month prospective single-center study, 1% sirolimus cream was applied daily to facial angiofibromas (FAs), fibrous cephalic plaques (FCPs), shagreen patches, hypomelanotic macules, and ungual fibromas. After complete clearance (CC) of FAs, we evaluated a maintenance protocol of 3 applications weekly.

RESULTS

Twenty-five patients were enrolled. Fifty percent obtained CC of FAs within 9 months. Of 7 patients with CC (58%) who were following the maintenance protocol, 6 relapsed within 7 months and 1 was still responding at 1 year. Of 16 patients with FCPs, 7 (44%) remained stable at 12 months and 9 (56%) improved after 3 to 9 months of treatment. Only 1 of 5 patients treated for shagreen patches showed improvement at 12 months. Treatment was well tolerated with no serious adverse events.

LIMITATIONS

The small number of patients was a limitation.

CONCLUSIONS

Topical 1% sirolimus applied daily produced positive responses in treatment of FAs, FCPs, and facial hypomelanotic macules and was well tolerated. A 3-times-weekly maintenance protocol did not prevent FA relapses.

Study of metastatic kinetics in metastatic melanoma treated with B-RAF inhibitors: Introducing mathematical modelling of kinetics into the therapeutic decision

Background

Evolution of metastatic melanoma (MM) under B-RAF inhibitors (BRAFi) is unpredictable, but anticipation is crucial for therapeutic decision. Kinetics changes in metastatic growth are driven by molecular and immune events, and thus we hypothesized that they convey relevant information for decision making.

Patients and methods

We used a retrospective cohort of 37 MM patients treated by BRAFi only with at least 2 close CT-scans available before BRAFi, as a model to study kinetics of metastatic growth before, under and after BRAFi. All metastases (mets) were individually measured at each CT-scan. From these measurements, different measures of growth kinetics of each met and total tumor volume were computed at different time points. A historical cohort permitted to build a reference model for the expected spontaneous disease kinetics without BRAFi. All variables were included in Cox and multistate regression models for survival, to select best candidates for predicting overall survival.

Results

Before starting BRAFi, fast kinetics and moreover a wide range of kinetics (fast and slow growing mets in a same patient) were pejorative markers. At the first assessment after BRAFi introduction, high heterogeneity of kinetics predicted short survival, and added independent information over RECIST progression in multivariate analysis. Metastatic growth rates after BRAFi discontinuation was usually not faster than before BRAFi introduction, but they were often more heterogeneous than before.

Conclusions

Monitoring kinetics of different mets before and under BRAFi by repeated CT-scan provides information for predictive mathematical modelling. Disease kinetics deserves more interest

The scalp hair collar and tuft signs: A retrospective multicenter study of 78 patients with a systematic review of the literature

BACKGROUND

Hair collar sign (HCS) and hair tuft of the scalp (HTS) are cutaneous signs of an underlying neuroectodermal defect, but most available data are based on case reports.

OBJECTIVE

We sought to define the clinical spectrum of HCS and HTS, clarify the risk for underlying neurovascular anomalies, and provide imaging recommendations.

METHODS

A 10-year multicenter retrospective and prospective analysis of clinical, radiologic, and histopathologic features of HCS and HTS in pediatric patients was performed.

RESULTS

Of the 78 patients included in the study, 56 underwent cranial and brain imaging. Twenty-three of the 56 patients (41%) had abnormal findings, including the following: (1) cranial/bone defect (30.4%), with direct communication with the central nervous system in 28.6%; (2) venous malformations (25%); or (3) central nervous system abnormalities (12.5%). Meningeal heterotopia in 34.6% (9/26) was the most common neuroectodermal association. Sinus pericranii, paraganglioma, and combined nevus were also identified.

LIMITATIONS

The partial retrospective design and predominant recruitment from the dermatology department are limitations of this study.

CONCLUSIONS

Infants with HCS or HTS are at high risk for underlying neurovascular anomalies. Magnetic resonance imaging scans should be performed in order to refer the infant to the appropriate specialist for management.

[Multiple primary cutaneous plasmacytoma]

BACKGROUND

Primary cutaneous plasmacytoma is a rare form of cutaneous B-cell lymphoma.

PATIENTS AND METHODS

A 51 year-old male with an unremarkable history gradually presented erythematous papulonodular lesions that had appeared gradually over the whole body throughout a two-year period and showing histologic and immunohistochemical features of cutaneous plasmacytoma. Staging investigations confirmed the primary character of the disease, and because of this and the absence of functional impairment, we opted for therapeutic abstention. No progression was noted after 4 years of regular monitoring.

DISCUSSION

Primary cutaneous plasmacytoma (PCP) is characterized by clonal proliferation of plasma cells in skin. Multiple PCPs are extremely rare and to date have been treated in most cases by chemotherapy, either with or without radiotherapy. The prognosis is poor, with 2-year survival of only 25%. The present case is original, being the only one to our knowledge in which therapeutic abstention was followed by a lack of progression after 4 years of regular follow-up. Consequently, certain indolent forms of PCP do not warrant automatic institution of chemotherapy.