Digital decision support for structural improvement of melanoma tumor boards: using standard cases to optimize workflow.

PURPOSE: Choosing optimal cancer treatment is challenging, and certified cancer centers must present all patients in multidisciplinary tumor boards (MDT). Our aim was to develop a decision support system (DSS) to provide treatment recommendations for apparently simple cases already at conference registration and to classify these as "standard cases". According to certification requirements, discussion of standard cases is optional and would thus allow more time for complex cases. METHODS: We created a smartphone query that simulated a tumor conference registration and requested all information needed to provide a recommendation. In total, 111 out of 705 malignant melanoma cases discussed at a skin cancer center from 2017 to 2020 were identified as potential standard cases, for which a digital twin recommendation was then generated by DSS. RESULTS: The system provided reliable advice in all 111 cases and showed 97% concordance of MDT and DSS for therapeutic recommendations, regardless of tumor stage. Discrepancies included two cases (2%) where DSS advised discussions at MDT and one case (1%) with deviating recommendation due to advanced patient age. CONCLUSIONS: Our work aimed not to replace clinical expertise but to alleviate MDT workload and enhance focus on complex cases. Overall, our DSS proved to be a suitable tool for identifying standard cases as such, providing correct treatment recommendations, and thus reducing the time burden of tumor conferences in favor for the comprehensive discussion of complex cases. The aim is to implement the DSS in routine tumor board software for further qualitative assessment of its impact on oncological care.

Manifestation of subacute cutaneous lupus erythematosus during treatment with anti-PD-1 antibody cemiplimab - a case report.

Introduction: The anti-programmed cell death protein 1 (PD-1) antibody cemiplimab has shown promising results in the treatment of unresectable or metastatic squamous cell carcinoma, however, frequently leads to immune-related adverse events limiting therapy efficacy. Although cutaneous side effects are common, only very few cases of cutaneous lupus erythematosus have been reported under anti-PD-1 immunotherapy. So far, no case of cutaneous lupus has been described under treatment with cemiplimab. Case report: For the first time, we report the case of a patient with advanced squamous cell carcinoma, who developed clinical and histological findings in sun-exposed skin that were consistent with anti-SS-A/Ro antibody-positive subacute cutaneous lupus erythematosus (SCLE) under treatment with cemiplimab. Additionally, laboratory chemical analyses revealed a severe immune-related hepatitis without clinical symptoms. Both, the SCLE and the hepatitis, resolved after the administration of topical and systemic steroids and the discontinuation of anti-PD-1 therapy. Conclusion: Treatment with cemiplimab can be associated with the appearance of cutaneous lupus erythematosus in sun-exposed areas. Application of topical and systemic glucocorticoids can lead to a rapid resolution of the skin eruptions. Moreover, our case illustrates the possibility of simultaneously occurring severe immune-related adverse events. This highlights the importance of additional diagnostics to avoid overlooking additional immune-related adverse events.

Mmp14 is required for matrisome homeostasis and circadian rhythm in fibroblasts.

The circadian clock in tendon regulates the daily rhythmic synthesis of collagen-I and the appearance and disappearance of small-diameter collagen fibrils in the extracellular matrix. How the fibrils are assembled and removed is not fully understood. Here, we first showed that the collagenase, membrane type I-matrix metalloproteinase (MT1-MMP, encoded by Mmp14), is regulated by the circadian clock in postnatal mouse tendon. Next, we generated tamoxifen-induced Col1a2-Cre-ERT2::Mmp14 KO mice (Mmp14 conditional knockout (CKO)). The CKO mice developed hind limb dorsiflexion and thickened tendons, which accumulated narrow-diameter collagen fibrils causing ultrastructural disorganization. Mass spectrometry of control tendons identified 1195 proteins of which 212 showed time-dependent abundance. In Mmp14 CKO mice 19 proteins had reversed temporal abundance and 176 proteins lost time dependency. Among these, the collagen crosslinking enzymes lysyl oxidase-like 1 (LOXL1) and lysyl hydroxylase 1 (LH1; encoded by Plod2) were elevated and had lost time-dependent regulation. High-pressure chromatography confirmed elevated levels of hydroxylysine aldehyde (pyridinoline) crosslinking of collagen in CKO tendons. As a result, collagen-I was refractory to extraction. We also showed that CRISPR-Cas9 deletion of Mmp14 from cultured fibroblasts resulted in loss of circadian clock rhythmicity of period 2 (PER2), and recombinant MT1-MMP was highly effective at cleaving soluble collagen-I but less effective at cleaving collagen pre-assembled into fibrils. In conclusion, our study shows that circadian clock-regulated Mmp14 controls the rhythmic synthesis of small diameter collagen fibrils, regulates collagen crosslinking, and its absence disrupts the circadian clock and matrisome in tendon fibroblasts.

TIGIT+ NK cells in combination with specific gut microbiota features predict response to checkpoint inhibitor therapy in melanoma patients.

BACKGROUND: Composition of the intestinal microbiota has been correlated to therapeutic efficacy of immune checkpoint inhibitors (ICI) in various cancer entities including melanoma. Prediction of the outcome of such therapy, however, is still unavailable. This prospective, non-interventional study was conducted in order to achieve an integrated assessment of the connection between a specific intestinal microbiota profile and antitumor immune response to immune checkpoint inhibitor therapy (anti-PD-1 and/or anti-CTLA-4) in melanoma patients. METHODS: We assessed blood and stool samples of 29 cutaneous melanoma patients who received immune checkpoint inhibitor therapy. For functional and phenotypical immune analysis, 12-color flow cytometry and FluoroSpot assays were conducted. Gut microbiome was analyzed with shotgun metagenomics sequencing. To combine clinical, microbiome and immune variables, we applied the Random Forest algorithm. RESULTS: A total of 29 patients was analyzed in this study, among whom 51.7% (n = 15) reached a durable clinical benefit. The Immune receptor TIGIT is significantly upregulated in T cells (p = 0.0139) and CD56high NK cells (p = 0.0037) of responders. Several bacterial taxa were associated with response (e.g. Ruminococcus torques) or failure (e.g. Barnesiella intestinihominis) to immune therapy. A combination of two microbiome features (Barnesiella intestinihominis and the Enterobacteriaceae family) and one immune feature (TIGIT+ CD56high NK cells) was able to predict response to ICI already at baseline (AUC = 0.85; 95% CI: 0.841-0.853). CONCLUSIONS: Our results reconfirm a link between intestinal microbiota and response to ICI therapy in melanoma patients and furthermore point to TIGIT as a promising target for future immunotherapies.

Tebentafusp in Patients with Metastatic Uveal Melanoma: A Real-Life Retrospective Multicenter Study.

BACKGROUND: Tebentafusp has recently been approved for the treatment of metastatic uveal melanoma (mUM) after proving to have survival benefits in a first-line setting. PATIENTS AND METHODS: This retrospective, multicenter study analyzed the outcomes and safety of tebentafusp therapy in 78 patients with mUM. RESULTS: Patients treated with tebentafusp had a median PFS of 3 months (95% CI 2.7 to 3.3) and a median OS of 22 months (95% CI 10.6 to 33.4). In contrast to a published Phase 3 study, our cohort had a higher rate of patients with elevated LDH (65.4% vs. 35.7%) and included patients with prior systemic and local ablative therapies. In patients treated with tebentafusp following ICI, there was a trend for a longer median OS (28 months, 95% CI 26.9 to 29.1) compared to the inverse treatment sequence (24 months, 95% CI 13.0 to 35.0, p = 0.257). The most common treatment-related adverse events were cytokine release syndrome in 71.2% and skin toxicity in 53.8% of patients. Tumor lysis syndrome occurred in one patient. CONCLUSIONS: Data from this real-life cohort showed a median PFS/OS similar to published Phase 3 trial data. Treatment with ICI followed by tebentafusp may result in longer PFS/OS compared to the inverse treatment sequence.

Tebentafusp in combination with durvalumab and/or tremelimumab in patients with metastatic cutaneous melanoma: a phase 1 study.

BACKGROUND: Immune checkpoint inhibitors have significantly improved outcomes in first line cutaneous melanoma. However, there is a high unmet need for patients who progress on these therapies and combination therapies are being explored to improve outcomes. Tebentafusp is a first-in-class gp100×CD3 ImmTAC bispecific that demonstrated overall survival (OS) benefit (HR 0.51) in metastatic uveal melanoma despite a modest overall response rate of 9%. This phase 1b trial evaluated the safety and initial efficacy of tebentafusp in combination with durvalumab (anti-programmed death ligand 1 (PDL1)) and/or tremelimumab (anti-cytotoxic T lymphocyte-associated antigen 4) in patients with metastatic cutaneous melanoma (mCM), the majority of whom progressed on prior checkpoint inhibitors. METHODS: In this open-label, multicenter, phase 1b, dose-escalation trial, HLA-A*02:01-positive patients with mCM received weekly intravenous tebentafusp with increasing monthly doses of durvalumab and/or tremelimumab starting day 15 of each cycle. The primary objective was to identify the maximum tolerated dose (MTD) or recommended phase 2 dose for each combination. Efficacy analyses were performed in all tebentafusp with durvalumab±tremelimumab treated patients with a sensitivity analysis in those who progressed on prior anti-PD(L)1 therapy. RESULTS: 85 patients were assigned to receive tebentafusp in combination with durvalumab (n=43), tremelimumab (n=13), or durvalumab and tremelimumab (n=29). Patients were heavily pretreated with a median of 3 prior lines of therapy, including 76 (89%) who received prior anti-PD(L)1. Maximum target doses of tebentafusp (68 mcg) alone or in combination with durvalumab (20 mg/kg) and tremelimumab (1 mg/kg) were tolerated; MTD was not formally identified for any arm. Adverse event profile was consistent with each individual therapy and there were no new safety signals nor treatment-related deaths. In the efficacy subset (n=72), the response rate was 14%, tumor shrinkage rate was 41% and 1-year OS rate was 76% (95% CI: 70% to 81%). The 1-year OS for triplet combination (79%; 95% CI: 71% to 86%) was similar to tebentafusp plus durvalumab (74%; 95% CI: 67% to 80%). CONCLUSION: At maximum target doses, the safety of tebentafusp with checkpoint inhibitors was consistent with safety of each individual therapy. Tebentafusp with durvalumab demonstrated promising efficacy in heavily pretreated patients with mCM, including those who progressed on prior anti-PD(L)1. TRIAL REGISTRATION NUMBER: NCT02535078.

C-Reactive Protein and Lymphocyte-to-Monocyte Ratio Predict Recurrence in Stage III Melanoma Patients with Microscopic Sentinel Lymph Node Metastasis.

Although adjuvant therapies with immune checkpoint inhibitors (ICI) and BRAF/MEK inhibitors improve recurrence-free survival (RFS) in stage III melanoma patients significantly, prognostic factors are needed to identify patients with a high risk of disease recurrence. Therefore, the aim of our study was to investigate the prognostic potential of routinely collected blood parameters for stage III melanoma patients with microscopic sentinel lymph node (SLN) metastasis. Altogether, we retrospectively analyzed 138 stage III melanoma patients who were diagnosed with microscopic SLN metastasis at the skin cancer center of the University Hospital Cologne between 2011 and 2020 and who did not receive prior adjuvant therapy with ICI or BRAF/MEK-inhibitors. Univariate and multivariate Cox regression analyses, Kaplan-Meier survival analyses and receiver operating characteristic (ROC) curves were performed to assess the impact of preoperatively collected blood parameters and blood ratios on recurrence-free survival (RFS; primary endpoint) and overall survival (OS). A high neutrophil-to-lymphocyte ratio (NLR), low lymphocyte-to-monocyte ratio (LMR) and high C-reactive protein (CRP) value were significantly associated with shorter RFS in multivariate analysis. For LMR (cut-off 3.5) and for CRP (cut-off 3.0) this effect remained after dichotomization. CRP showed a stronger association with RFS than NLR or LMR, with the highest association being detected for the combination of low LMR and high CRP. Additionally, derived NLR ≥ 2.0 was significantly associated with shorter OS in multivariate analysis. In summary, our data suggest that CRP in combination with LMR should be considered as a marker for melanoma recurrence in stage III melanoma patients with microscopic SLN metastasis.

Oligometastatic disease and visceral resections in advanced malignant melanoma: a propensity-matched analysis.

PURPOSE: Malignant melanoma is among the tumours with the highest increase in incidence of solid tumours in Germany. While most patients are diagnosed at an early stage and show a good prognosis, advanced stages of malignant melanoma are accompanied with a poor prognosis and limited treatment options. Comparable to other tumour entities, the resection of visceral metastases could lead to a better prognosis. Supplementary, the subgroup of oligometastatic patients might benefit from surgical therapy to a greater extent. METHODS: This retrospective study analysed 351 patients treated between 2006 and 2017 at the University Hospital of Cologne. A total of 121 patients showed visceral metastases, with which we compared patients with a diffuse tumour spread to patients in an oligometastatic state. Furthermore, we evaluated the effect of visceral resection of oligometastatic, malignant melanoma. RESULTS: Our analysis showed that patients with an oligometastatic malignant melanoma had a significantly better prognosis than patients with a diffuse pattern of metastases, if they showed visceral metastases. Furthermore, the resection of visceral metastases leads to a significant gain in median overall survival time (13.6 vs. 34.2 months) and in progression-free survival (9.6 vs. 3.8 months). CONCLUSION: The resection of visceral metastases is a rational treatment option in advanced malignant melanoma. Although our study is limited by a small cohort of patients (n = 18), we believe that the resection of visceral metastases will be fundamental in the treatment of malignant melanoma. In particular, patients in an oligometastatic stage could be an eligible group for surgical treatment.

Real-world outcomes using PD-1 antibodies and BRAF + MEK inhibitors for adjuvant melanoma treatment from 39 skin cancer centers in Germany, Austria and Switzerland.

BACKGROUND: Programmed death-1 (PD-1) antibodies and BRAF + MEK inhibitors are widely used for adjuvant therapy of fully resected high-risk melanoma. Little is known about treatment efficacy outside of phase III trials. This real-world study reports on clinical outcomes of modern adjuvant melanoma treatment in specialized skin cancer centers in Germany, Austria and Switzerland. METHODS: Multicenter, retrospective study investigating stage III-IV melanoma patients receiving adjuvant nivolumab (NIV), pembrolizumab (PEM) or dabrafenib + trametinib (D + T) between 1/2017 and 10/2021. The primary endpoint was 12-month recurrence-free survival (RFS). Further analyses included descriptive and correlative statistics, and a multivariate linear-regression machine learning model to assess the risk of early melanoma recurrence. RESULTS: In total, 1198 patients from 39 skin cancer centers from Germany, Austria and Switzerland were analysed. The vast majority received anti PD-1 therapies (n = 1003). Twelve-month RFS for anti PD-1 and BRAF + MEK inhibitor-treated patients were 78.1% and 86.5%, respectively (hazard ratio [HR] 1.998 [95% CI 1.335-2.991]; p = 0.001). There was no statistically significant difference in overall survival (OS) in anti PD-1 (95.8%) and BRAF + MEK inhibitor (96.9%) treated patients (p > 0.05) during the median follow-up of 17 months. Data indicates that anti PD-1 treated patients who develop immune-related adverse events (irAEs) have lower recurrence rates compared to patients with no irAEs (HR 0.578 [95% CI 0.443-0.754], p = 0.001). BRAF mutation status did not affect overall efficacy of anti PD-1 treatment (p > 0.05). In both, anti PD-1 and BRAF + MEK inhibitor treated cohorts, data did not show any difference in 12-month RFS and 12-month OS comparing patients receiving total lymph node dissection (TLND) versus sentinel lymph node biopsy only (p > 0.05). The recurrence prediction model reached high specificity but only low sensitivity with an AUC = 0.65. No new safety signals were detected. Overall, recorded numbers and severity of adverse events were lower than reported in pivotal phase III trials. CONCLUSIONS: Despite recent advances in adjuvant melanoma treatment, early recurrence remains a significant clinical challenge. This study shows that TLND does not reduce the risk of early melanoma recurrence and should only be considered in selected patients. Data further highlight that variables collected during clinical routine are unlikely to allow for a clinically relevant prediction of individual recurrence risk.

[Melanoma microenvironment-impact of modern therapies]. / Tumormikromilieu des Melanoms ­ Einfluss moderner Therapien.

BACKGROUND: A considerable proportion of patients with advanced melanoma succumb to metastatic disease despite the initial success of modern therapies. OBJECTIVES: An overview of the melanoma tumor microenvironment with special focus on approved therapies and new innovative strategies is given. METHODS: Current clinical trials and scientific insights concerning the impact of the tumor microenvironment on progression and therapy of advanced melanoma are reviewed and discussed. RESULTS: The tumor microenvironment with its manifold components and interactions plays a major role in the treatment of malignant melanoma. CONCLUSION: Innovative new strategies that target an immunosuppressive microenvironment may improve the therapeutic efficacy of current treatment of advanced melanoma.

Role of MMP3 and fibroblast-MMP14 in skin homeostasis and repair.

Early lethality of mice with complete deletion of the matrix metalloproteinase MMP14 emphasized the proteases' pleiotropic functions. MMP14 deletion in adult dermal fibroblasts (MMP14Sf-/-) caused collagen type I accumulation and upregulation of MMP3 expression. To identify the compensatory role of MMP3, mice were generated with MMP3 deletion in addition to MMP14 loss in fibroblasts. These double deficient mice displayed a fibrotic phenotype in skin and tendons as detected in MMP14Sf-/- mice, but no additional obvious defects were detected. However, challenging the mice with full thickness excision wounds resulted in delayed closure of early wounds in the double deficient mice compared to wildtype and MMP14 single knockout controls. Over time wounds closed and epidermal integrity was restored. Interestingly, on day seven, post-wounding myofibroblast density was lower in the wounds of all knockout than in controls, they were higher on day 14. The delayed resolution of myofibroblasts from the granulation tissue is paralleled by reduced apoptosis of these cells, although proliferation of myofibroblasts is induced in the double deficient mice. Further analysis showed comparable TGFß1 and TGFßR1 expression among all genotypes. In addition, in vitro, fibroblasts lacking MMP3 and MMP14 retained their ability to differentiate into myofibroblasts in response to TGFß1 treatment and mechanical stress. However, in vivo, p-Smad2 was reduced in myofibroblasts at day 5 post-wounding, in double, but most significant in single knockout, indicating their involvement in TGFß1 activation. Thus, although MMP3 does not compensate for the lack of fibroblast-MMP14 in tissue homeostasis, simultaneous deletion of both proteases in fibroblasts delays wound closure during skin repair. Notably, single and double deficiency of these proteases modulates myofibroblast formation and resolution in wounds.

Integrated, cross-sectoral psycho-oncology (isPO): a new form of care for newly diagnosed cancer patients in Germany.

BACKGROUND: The annual incidence of new cancer cases has been increasing worldwide for many years, and is likely to continue to rise. In Germany, the number of new cancer cases is expected to increase by 20% until 2030. Half of all cancer patients experience significant emotional and psychosocial distress along the continuum of their disease, treatment, and aftercare, and also as long-term survivors. Consequently, in many countries, psycho-oncological programs have been developed to address this added burden at both the individual and population level. These programs promote the active engagement of patients in their cancer therapy, aftercare and survivorship planning and aim to improve the patients' quality of life. In Germany, the "new form of care isPO" ("nFC-isPO"; integrated, cross-sectoral psycho-oncology/integrierte, sektorenübergreifende Psycho-Onkologie) is currently being developed, implemented and evaluated. This approach strives to accomplish the goals devised in the National Cancer Plan by providing psycho-oncological care to all cancer patients according to their individual healthcare needs. The term "new form of care" is defined by the Innovation Fund (IF) of Germany's Federal Joint Committee as "a structured and legally binding cooperation between different professional groups and/or institutions in medical and non-medical care". The nFC-isPO is part of the isPO project funded by the IF. It is implemented in four local cancer centres and is currently undergoing a continuous quality improvement process. As part of the isPO project the nFC-isPO is being evaluated by an independent institution: the Institute for Medical Sociology, Health Services Research, and Rehabilitation Science (IMVR), University of Cologne, Germany. The four-year isPO project was selected by the IF to be eligible for funding because it meets the requirements of the federal government's National Cancer Plan (NCP), in particular, the "further development of the oncological care structures and quality assurance" in the psycho-oncological domain. An independent evaluation is required by the IF to verify if the new form of care leads to an improvement in cross-sectoral care and to explore its potential for permanent integration into the German health care system. METHODS: The nFC-isPO consists of six components: a concept of care (C1), care pathways (C2), a psycho-oncological care network (C3), a care process organization plan (C4), an IT-supported documentation and assistance system (C5) and a quality management system (C6). The two components concept of care (C1) and care pathways (C2) represent the isPO clinical care program, according to which the individual cancer patients are offered psycho-oncological services within a period of 12 months after program enrolment following the diagnosis of cancer. The remaining components (C3-C6) represent the formal-administrative aspects of the nFC-isPO that are intended to meet the legally binding requirements of patient care in the German health care system. With the aim of systematic development of the nFC-isPO while at the same time enabling the external evaluators to examine its quality, effectiveness and efficiency under conditions of routine care, the project partners took into consideration approaches from translational psycho-oncology, practice-based health care research and program theory. In order to develop a structured, population-based isPO care program, reference was made to a specific program theory, to the stepped-care approach, and also to evidence-based guideline recommendations. RESULTS: The basic version, nFC-isPO, was created over the first year after the start of the isPO project in October 2017, and has since been subject to a continuous quality improvement process. In 2019, the nFC-isPO was implemented at four local psycho-oncological care networks in the federal state North Rhine-Westphalia, in Germany. The legal basis of the implementation is a contract for "special care" with the German statutory health insurance funds according to state law (§ 140a SCB V; Social Code Book V for the statutory health insurance funds). Besides the accompanying external evaluation by the IMVR, the nFC-isPO is subjected to quarterly internal and cross-network quality assurance and improvement measures (internal evaluation) in order to ensure continuous quality improvement process. These quality management measures are developed and tested in the isPO project and are to be retained in order to ensure the sustainability of the quality of nFC-isPO for later dissemination into the German health care system. DISCUSSION: Demands on quality, effectiveness and cost-effectiveness of in the German health care system are increasing, whereas financial resources are declining, especially for psychosocial services. At the same time, knowledge about evidence-based screening, assessment and intervention in cancer patients and about the provision of psychosocial oncological services is growing continuously. Due to the legal framework of the statutory health insurance in Germany, it has taken years to put sound psycho-oncological findings from research into practice. Ensuring the adequate and sustainable financing of a needs-oriented, psycho-oncological care approach for all newly diagnosed cancer patients, as required by the NCP, may still require many additional years. The aim of the isPO project is to develop a new form of psycho-oncological care for the individual and the population suffering from cancer, and to provide those responsible for German health policy with a sound basis for decision-making on the timely dissemination of psycho-oncological services in the German health care system. TRIAL REGISTRATION: The study was pre-registered at the German Clinical Trials Register (https://www.drks.de/DRKS00015326) under the following trial registration number: DRKS00015326 ; Date of registration: October 30, 2018.

XIAP promotes melanoma growth by inducing tumour neutrophil infiltration.

Elevated expression of the X-linked inhibitor of apoptosis protein (XIAP) has been frequently reported in malignant melanoma suggesting that XIAP renders apoptosis resistance and thereby supports melanoma progression. Independent of its anti-apoptotic function, XIAP mediates cellular inflammatory signalling and promotes immunity against bacterial infection. The pro-inflammatory function of XIAP has not yet been considered in cancer. By providing detailed in vitro analyses, utilising two independent mouse melanoma models and including human melanoma samples, we show here that XIAP is an important mediator of melanoma neutrophil infiltration. Neutrophils represent a major driver of melanoma progression and are increasingly considered as a valuable therapeutic target in solid cancer. Our data reveal that XIAP ubiquitylates RIPK2, involve TAB1/RIPK2 complex and induce the transcriptional up-regulation and secretion of chemokines such as IL8, that are responsible for intra-tumour neutrophil accumulation. Alteration of the XIAP-RIPK2-TAB1 inflammatory axis or the depletion of neutrophils in mice reduced melanoma growth. Our data shed new light on how XIAP contributes to tumour growth and provides important insights for novel XIAP targeting strategies in cancer.

Oncologic Outcome and Immune Responses of Radiotherapy with Anti-PD-1 Treatment for Brain Metastases Regarding Timing and Benefiting Subgroups.

While immune checkpoint inhibitors (ICIs) in combination with radiotherapy (RT) are widely used for patients with brain metastasis (BM), markers that predict treatment response for combined RT and ICI (RT-ICI) and their optimal dosing and sequence for the best immunogenic effects are still under investigation. The aim of this study was to evaluate prognostic factors for therapeutic outcome and to compare effects of concurrent and non-concurrent RT-ICI. We retrospectively analyzed data of 93 patients with 319 BMs of different cancer types who received PD-1 inhibitors and RT at the University Hospital Cologne between September/2014 and November/2020. Primary study endpoints were overall survival (OS), progression-free survival (PFS), and local control (LC). We included 66.7% melanoma, 22.8% lung, and 5.5% other cancer types with a mean follow-up time of 23.8 months. Median OS time was 12.19 months. LC at 6 months was 95.3% (concurrent) vs. 69.2% (non-concurrent; p = 0.008). Univariate Cox regression analysis detected following prognostic factors for OS: neutrophil-to-lymphocyte ratio NLR favoring <3 (low; HR 2.037 (1.184−3.506), p = 0.010), lactate dehydrogenase (LDH) favoring ≤ULN (HR 1.853 (1.059−3.241), p = 0.031), absence of neurological symptoms (HR 2.114 (1.285−3.478), p = 0.003), RT concept favoring SRS (HR 1.985 (1.112−3.543), p = 0.019), RT dose favoring ≥60 Gy (HR 0.519 (0.309−0.871), p = 0.013), and prior anti-CTLA4 treatment (HR 0.498 (0.271−0.914), p = 0.024). Independent prognostic factors for OS were concurrent RT-ICI application (HR 0.539 (0.299−0.971), p = 0.024) with a median OS of 17.61 vs. 6.83 months (non-concurrent), ECOG performance status favoring 0 (HR 7.756 (1.253−6.061), p = 0.012), cancer type favoring melanoma (HR 0.516 (0.288−0.926), p = 0.026), BM volume (PTV) favoring ≤3 cm3 (HR 1.947 (1.007−3.763), p = 0.048). Subgroups with the following factors showed significantly longer OS when being treated concurrently: RT dose <60 Gy (p = 0.014), PTV > 3 cm3 (p = 0.007), other cancer types than melanoma (p = 0.006), anti-CTLA4-naïve patients (p < 0.001), low NLR (p = 0.039), steroid intake ≤4 mg (p = 0.042). Specific immune responses, such as abscopal effects (AbEs), pseudoprogression (PsP), or immune-related adverse events (IrAEs), occurred more frequently with concurrent RT-ICI and resulted in better OS. Other toxicities, including radionecrosis, were not statistically different in both groups. The concurrent application of RT and ICI, the ECOG-PS, cancer type, and PTV had an independently prognostic impact on OS. In concurrently treated patients, treatment response (LC) was delayed and specific immune responses (AbE, PsP, IrAE) occurred more frequently with longer OS rates. Our results suggest that concurrent RT-ICI application is more beneficial than sequential treatment in patients with low pretreatment inflammatory status, more and larger BMs, and with other cancer types than melanoma.

Post-transplant Malignancies Show Reduced T-cell Abundance and Tertiary Lymphoid Structures as Correlates of Impaired Cancer Immunosurveillance.

PURPOSE: An increased risk to develop cancer is one of the most challenging negative side effects of long-term immunosuppression in organ transplant recipients and impaired cancer immunosurveillance is assumed as underlying mechanism. This study aims to elucidate transplant-related changes in the tumor immune microenvironment (TME) of cancer. EXPERIMENTAL DESIGN: Data from 123 organ transplant recipients (kidney, heart, lung, and liver) were compared with historic data from non-immunosuppressed patients. Digital image analysis of whole-section slides was used to assess abundance and spatial distribution of T cells and tertiary lymphoid structures (TLS) in the TME of 117 tumor samples. Expression of programmed cell death 1 ligand 1 (PD-L1) and human-leucocyte-antigen class I (HLA-I) was assessed on tissue microarrays. RESULTS: We found a remarkably reduced immune infiltrate in the center tumor (CT) regions as well as the invasive margins (IM) of post-transplant cancers. These differences were more pronounced in the IM than in the CT and larger for CD8+ T cells than for CD3+ T cells. The Immune-score integrating results from CT and IM was also lower in transplant recipients. Density of TLS was lower in cancer samples of transplant recipients. The fraction of samples with PD-L1 expression was higher in controls whereas decreased expression of HLA-I was more common in transplant recipients. CONCLUSIONS: Our study demonstrates the impact of immunosuppression on the TME and supports impaired cancer immunosurveillance as important cause of post-transplant cancer. Modern immunosuppressive protocols and cancer therapies should consider the distinct immune microenvironment of post-transplant malignancies.

Loss of Endothelial Cell Matrix Metalloproteinase 14 Reduces Melanoma Growth and Metastasis by Increasing Tumor Vessel Stability.

Matrix metalloproteinase (MMP) 14 belongs to a large family of zinc-dependent endopeptidases and plays a critical role in skin physiological and pathological processes. Complete loss of the protease resulted in severe developmental defects leading to early death. However, because of the premature death of the mice, the functional significance for endothelial cell (EC) expression of MMP14 in skin physiology and pathology in vivo after birth is yet unknown. Using a mouse model with constitutive EC-specific deletion of Mmp14 (Mmp14EC‒/‒), we showed that mice developed and bred normal, but melanoma growth and metastasis were reduced. Although vascularity was unaltered, vessel permeability was decreased. Deletion of MMP14 in ECs led to increased vessel coverage by pericytes and vascular endothelial-cadherin expression in mice in vivo and in vitro but not in human ECs. Endothelial nitric oxide synthase expression and nitric oxide production were significantly reduced in Mmp14EC‒/‒ ECs and MMP14-silenced human umbilical vein ECs. A direct correlation between endothelial nitric oxide synthase and MMP14 expression was detected in intratumoral vessels of human malignant melanomas. Altogether, we show that endothelial MMP14 controls tumor vessel function during melanoma growth. These data suggest that EC-derived MMP14 direct targeting alone or with vascular stabilizing agents may be therapeutically crucial in inhibiting melanoma growth and metastasis.