Neutrophils activated by membrane attack complexes increase the permeability of melanoma blood vessels.

The microenvironment of malignant melanomas defines the properties of tumor blood vessels and regulates infiltration and vascular dissemination of immune and cancer cells, respectively. Previous research in other cancer entities suggested the complement system as an essential part of the tumor microenvironment. Here, we confirm activation of the complement system in samples of melanoma patients and murine melanomas. We identified the tumor endothelium as the starting point of the complement cascade. Generation of complement-derived C5a promoted the recruitment of neutrophils. Upon contact with the vascular endothelium, neutrophils were further activated by complement membrane attack complexes (MACs). MAC-activated neutrophils release neutrophil extracellular traps (NETs). Close to the blood vessel wall, NETs opened the endothelial barrier as indicated by an enhanced vascular leakage. This facilitated the entrance of melanoma cells into the circulation and their systemic spread. Depletion of neutrophils or lack of MAC formation in complement component 6 (C6)-deficient animals protected the vascular endothelium and prevented vascular intravasation of melanoma cells. Our data suggest that inhibition of MAC-mediated neutrophil activation is a potent strategy to abolish hematogenous dissemination in melanoma.

532-nm potassium titanyl-phosphate laser versus 595-nm pulsed dye laser for port-wine birthmarks: A prospective, randomized, split-side study.

BACKGROUND: Pulsed dye lasers (PDL) are currently the first-line treatment of port-wine birthmarks (PWB). Due to high maintenance costs and instable technology, alternative methods are needed. OBJECTIVES: To compare clinical outcomes of a variable-sequenced, long-pulsed 532-nm potassium titanyl-phosphate (KTP) laser and PDL on treating PWB. METHODS: A prospective, randomized, split-side study. Patients were treated with a KTP laser and PDL with 1 to 5 sessions at intervals of 6-8 weeks. A follow-up visit was scheduled 6 weeks post-treatment. Efficacy was evaluated through colorimetric analysis, area reduction measurements and clinical evaluations by two blinded investigators based on photo documentation. Subjects provided rating of pain intensity during treatment, post-treatment reactions and satisfaction. Safety was measured by adverse events. Maintenance issues of the laser systems were documented. RESULTS: A total of 35 patients (mean age 42.1 years) were enrolled. 63% were female. Patients received 2.4 (SD 1.4; 1-5) treatment sessions. Colorimetric analysis indicated a comparable clearance effect in PWB of both KTP laser and PDL. Independent investigators rated clinical appearance to be significantly improved compared to baseline. No significant difference was observed between both laser systems. Regarding post-treatment reactions, the KTP laser caused less swelling, purpura and crusts. 96% would recommend both treatment modalities. Patients were satisfied with both laser systems. During the study, PDL systems malfunctioned for 6.6 months in total. For the KTP laser, we did not observe any system failures. CONCLUSION: Our data indicate that the KTP laser of the latest generation with large-spot sizes, subpulse technology and cryogen cooling has a comparable efficacy to the PDL in treating PWB. In addition, KTP laser is associated with greater tolerability, fewer technical failures and lower repair costs. Further prospective studies are required to determine the true effectiveness of the KTP laser in PWB treatment. This study was preregistered in Clinicaltrials.gov (NCT05771298).

Differential predictive value of tissue-specific PD-L1 expression scores in adjuvant immunotherapy of melanoma.

BACKGROUND: Adjuvant treatment of stage II-IV melanoma with PD-1-based immune checkpoint inhibitors (ICI) has improved relapse-free survival (RFS) and has therefore become a standard-of-care treatment option. Approximately 25%-30% of patients still recur within 1 year. Predictive biomarkers reflecting real-world data are desired. The predictive relevance of tumour tissue PD-L1 expression in the adjuvant setting remains inconclusive. OBJECTIVES: This retrospective, observational study was conducted to evaluate the value of PD-L1 expression scores in different tumour tissue locations in predicting response towards adjuvant immunotherapeutic treatment. METHODS: Tumour tissue taken prior to anti-PD-1 adjuvant ICI in 243 stage II-IV melanoma patients was collected at University Skin Cancer Center Hamburg. PD-L1 expression was evaluated on immune cells (ICS), tumour cells (TPS) and combined (CPS). Scores were determined by independent pathological physician quantification and correlated with therapy outcome at different cut-off (CO) levels (relapse-free survival, RFS) for different tumour tissue locations (primary tumour, metastases). RESULTS: A total of 104 patients were eligible for analysis. Positivity of ICS, TPS and CPS showed no predictive RFS outcome association at different CO levels when analysed irrespective of tissue origin. In primary tumours, ICS at CO 1% showed a significantly improved RFS upon positivity (HR 0.22). In contrast, positivity to TPS (CO 1%) correlated significantly and independently with improved RFS when evaluated in metastatic tumour tissue specimens (HR 0.37). CONCLUSIONS: PD-L1 tumour tissue expression may serve as a predictive biomarker for adjuvant ICI treatment response stratification in melanoma, but caution should be spent on the origin of tumour tissue analysed. The cell-type relevant for the predictive value of PD-L1 expression is tissue-specific with immune cells being important in primary tumours while tumour cells are key in metastases. The present results should be validated in a multicentre cohort.

C-reactive protein flare predicts response to checkpoint inhibitor treatment in melanoma.

BACKGROUND: The treatment of melanoma has been revolutionized by the use of immune checkpoint inhibition (ICI), but many patients do not benefit. Furthermore, immune-related adverse events may occur during therapy. A predictive biomarker is needed to reliably identify patients benefitting. In lung, renal cell and bladder cancer early C-reactive protein (CRP) kinetics were shown to be a predictive biomarker for ICI. OBJECTIVE: Here, we investigate early CRP kinetics as predictive biomarker for ICI in melanoma patients. METHODS: Two independent prospectively collected cohorts were analysed: Cohort 1 (n = 87) with advanced and Cohort 2 (n = 99) with completely resected melanoma. Patients were stratified by in the dynamics of CRP after ICI initiation: A doubling of baseline CRP within 30 days followed by at least a 30% drop within 3 months was classified as a CRP flare. If no doubling of CRP was reported, but a 30% drop within 3 months, patients were classified as CRP responders and all others as CRP non-responders. Analysed factors included clinical characteristics like S100B and LDH. Median follow-up was 1.5 and 1.7 years for Cohorts 1 and 2. RESULTS: In Cohort 1 CRP flare (n = 12), CRP responders (n = 43) and CRP non-responders (n = 32) with a progression-free survival (PFS) of 0.7, 0.6 and 0.2 years (p = 0.017) and an overall survival (OS) of 2.2, 1.5 and 1.0 years (p = 0.014), respectively. Multivariable Cox analysis showed an independent risk reduction of progression for CRP responders by 62% compared to CRP non-responders (p = 0.001). In Cohort 2 CRP flare (n = 13), CRP responders (n = 70) and CRP non-responders (n = 16) the log-rank analysis showed a significant difference between OS and recurrence-free survival (RFS) curves (p = 0.046 and p = 0.049). CONCLUSION: Early CRP kinetics could indicate a response to ICI with improved OS and RFS/PFS. CRP flare and CRP response indicating significantly improved outcomes compared to CRP non-responders.

Mogamulizumab-associated rash - Case series and review of the literature.

Mogamulizumab, a monoclonal antibody directed against CC chemokine receptor 4, is approved as a second-line treatment of mycosis fungoides and Sézary syndrome. One of the most common side effects is mogamulizumab-associated rash (MAR), which can present in a variety of clinical and histological types. Clinically, it can be difficult to differentiate between MAR and progression of the underlying disease, so histological examination is crucial for clinicopathological correlation. Current data analyses suggest that MAR is more common in patients with Sézary syndrome and is associated with a significantly better response to treatment, making the distinction from disease progression particularly important. The management of MAR depends on its severity, and therapy may need to be paused. This article presents three cases from our clinic and reviews the current literature on MAR. It emphasizes the importance of understanding MAR in the management of patients with cutaneous lymphomas.

Telephone follow-up after outpatient nail surgery - a retrospective analysis.

BACKGROUND: One of the areas of care in dermatosurgery is the surgical treatment of diseases of the nail organ. Side effects and complications after nail surgery were investigated by telephone follow-up (TFU), and its suitability for postoperative monitoring and consultation was assessed. PATIENTS AND METHODS: All patients who underwent nail surgery at the Department of Dermatology at the Ludwigshafen City Hospital from October 2019 to December 2021 in outpatient setting were contacted by telephone on the second to third postoperative day and questioned in a standardized manner about postoperative complaints and counselled if necessary. RESULTS: A total of 100 cases were followed up. The most common procedures performed were phenol matricectomy (41%), nail avulsion (16%), and nail matrix biopsies (9%). 50% and 21% of patients reported pain on the day of the procedure and the day after surgery, respectively. After nail avulsion, pain was statistically significantly more frequently reported on the day following the procedure and pain medication was statistically significantly more frequently required (p  =  0.002). Serious adverse events did not occur after nail surgery. 10% of the respondents raised specific questions and needed counseling by TFU. CONCLUSIONS: All nail surgeries were well tolerated in the outpatient setting. Pain was the most common side effect, although only half of all patients reported pain on the day of surgery and only 21% on the day after the procedure. The TFU proved to be an effective and practical as well as easy to establish method for postoperative follow-up and consultation after outpatient nail surgery.

Local blood coagulation drives cancer cell arrest and brain metastasis in a mouse model.

Clinically relevant brain metastases (BMs) frequently form in cancer patients, with limited options for effective treatment. Circulating cancer cells must first permanently arrest in brain microvessels to colonize the brain, but the critical factors in this process are not well understood. Here, in vivo multiphoton laser-scanning microscopy of the entire brain metastatic cascade allowed unprecedented insights into how blood clot formation and von Willebrand factor (VWF) deposition determine the arrest of circulating cancer cells and subsequent brain colonization in mice. Clot formation in brain microvessels occurred frequently (>95%) and specifically at intravascularly arrested cancer cells, allowing their long-term arrest. An extensive clot embedded ∼20% of brain-arrested cancer cells, and those were more likely to successfully extravasate and form a macrometastasis. Mechanistically, the generation of tissue factor-mediated thrombin by cancer cells accounted for local activation of plasmatic coagulation in the brain. Thrombin inhibition by treatment with low molecular weight heparin or dabigatran and an anti-VWF antibody prevented clot formation, cancer cell arrest, extravasation, and the formation of brain macrometastases. In contrast, tumor cells were not able to directly activate platelets, and antiplatelet treatments did reduce platelet dispositions at intravascular cancer cells but did not reduce overall formation of BMs. In conclusion, our data show that plasmatic coagulation is activated early by intravascular tumor cells in the brain with subsequent clot formation, which led us to discover a novel and specific mechanism that is crucial for brain colonization. Direct or indirect thrombin and VWF inhibitors emerge as promising drug candidates for trials on prevention of BMs.

In vivo characterization of laser-assisted delivery of hyaluronic acid using multiphoton fluorescence lifetime imaging.

Laser-assisted drug delivery (LADD) is a treatment method to enhance the penetration of pharmaceuticals through the skin. The aim of the present study is to track hyaluronic acid (HA) and analyse its effect on human skin in vivo after ablative fractional laser (AFL) treatment. Healthy male and female subjects were recruited. Four areas were marked on their forearms of each volunteer, and each area was assigned to one of the following treatment options: AFL + HA, AFL only, HA only or untreated control. A carbon dioxide laser was used for the AFL treatment. Follow-up measurements were scheduled 30 min and 30 days after treatment using multiphoton tomography equipped with fluorescence lifetime imaging (MPT-FLIM). A total of 11 subjects completed the study. By detecting fluorescence lifetimes, the HA and the anaesthetic ointment were clearly distinguishable from surrounding tissue. After AFL treatment, HA could be visualized in all epidermal and upper dermal layers. In contrast, HA in intact skin was only detected in the superficial layers at distinctly lower levels. The applied HA gel seemed to have beneficial properties for the wound healing process after laser treatment. LADD has proven to be a fast and effective method to increase HA uptake into the skin, allowing for improved hydration and skin rejuvenation over time. Furthermore, LADD could be a beneficial treatment option in laser resurfacing. MPT-FLIM proved to be an appropriate diagnostic tool for drug delivery tracking and monitoring of treatment response for individualized therapy adjustment.

Thermal eye injuries from dermatologic laser treatments-an experimental study.

In recent years, severe ocular complications after dermatological laser therapies have been reported. One hypothesis is thermal damage due to heating of the metal eye shields. The aim of the present study is to evaluate the safety of ocular metal eye shields during laser therapy of the periocular region. For the experimental study, porcine eyelids were exposed to continuously increasing laser energy and multiple pulses using a number of dermatologic laser systems. Temperature differences of the convex and concave surface of metal eye shields were constantly measured using a thermocouple. Maximum increase of the convex surface of shields was + 8.9 °C (± 0.1 °C) provided by the long-pulsed alexandrite laser (20-25-J/cm2 energy, 15-mm spot size, 20-ms pulse duration, 1 Hz). Present data indicate that metal eye shields provide sufficient thermal protection when clinically used laser parameters are applied. Other safety precautions continue to be essential to protect both the patient and the laser operator. These include the use of nonreflective metal eye shields, precise knowledge of laser physics, and a clear understanding of how they interact with ocular and periocular anatomy.

Direct-to-Consumer Teledermatology in Germany: A Retrospective Analysis of 1,999 Teleconsultations Suggests Positive Impact on Patient Care.

Background: There is a high demand for dermatological care in Germany. As use of teledermatology has increased significantly, this study aimed to investigate the impact of teledermatology on patient care. Methods: This retrospective cross-sectional study used data from a direct-to-consumer teledermatology platform using store-and-forward technology available in Germany between July 2021 and April 2022. Additional patient characteristics were collected using a voluntary follow-up questionnaire, 28 days after teleconsultation. Results: Data of 1,999 enrolled patients were evaluated. Patients had a mean age of 36 years, and 61.2% (1,223/1,999) lived in a rural residence. The most common diagnoses included eczema (36.0%, 701/1,946), fungal diseases (15.4%, 299/1,946), and acne (12.5%, 243/1,946). The follow-up questionnaire was answered by 166 patients (8.3%, 166/1,999). In total, 42.8% (71/166) of patients had undergone no previous medical consultation. The most frequent reason for using teledermatology was the waiting time for a dermatology outpatient appointment (62.0%, 103/166). A total of 62.0% (103/166) participants rated the treatment success as good or very good, while 86.1% (143/166) rated the quality of telemedical care as equal or better to that of an outpatient visit. Conclusion: This study showed that patients often use teledermatology because of functional barriers (waiting times). In this cohort, the diagnoses strongly corresponded to reasons for outpatient presentation. Most patients rated the quality of teledermatology service as at least equivalent to that of outpatient physician visits and reported treatment success. Thus, teledermatology can relieve the burden of outpatient care while providing high benefits from the patient's perspective.

A Rejected Hypothesis: Phenomenon of High Treatment Adherence in Direct-to-Consumer Teledermatology Despite Lack of Direct Physician-Patient Interaction.

Background: Adherence to dermatological treatment is described as poor. Empathy and open communication in the physician-patient relationship has been proven to improve adherence. As direct-to-consumer teledermatology enables patients to access dermatological consultations without in-person interactions, we hypothesized treatment adherence in teledermatology to be low. Methods: The objective of the study was to examine treatment adherence in teledermatology. This retrospective cross-sectional study used data from patients treated through a German direct-to-consumer teledermatology platform between July 2021 and April 2022. Additional information was collected through voluntary follow-up questionnaires provided to patients to assess individual treatment success, treatment-related adverse events, and treatment adherence. Results: Data collection included 771 patients; 61.6% (475/771) were women (mean age 35 years). In 46% (355/771), skin disease had been present for <3 months before teleconsultation. Of all patients who answered the follow-up questionnaire (n = 228), 28.5% (65/228) reported treatment-related adverse events, with skin dryness being the most common (56.9%, 37/65). Adverse events resulting in treatment discontinuation were reported in 1.3% (3/228) of all cases. Improvement in skin condition on therapy was described by 75.4% (172/228). In 85.5% (195/228), full treatment adherence was reported. Conclusion: This is the first study worldwide to examine data on treatment adherence in direct-to-consumer-teledermatology. Despite the lack of doctor-patient interaction, the results of our study demonstrate that most patients show high treatment adherence. Possible drivers contributing to high compliance rates could be the high proportion of new-onset skin diseases, the high treatment success of the prescribed therapies, and the low rate of serious adverse events.

The potential of telemedicine for dermatological care of pediatric patients in Germany.

BACKGROUND AND OBJECTIVES: Skin diseases are a common reason for consultations in pediatric practice. The present study aims to characterize the dermatological requests of resident pediatric specialists using teledermatology in Germany. PATIENTS AND METHODS: This analysis of consultation requests, submitted by pediatricians to a designated pediatric dermatologist via a telemedical consultation system (PädExpert) using the store-and-forward technology, was performed between February 2021 and December 2021. RESULTS: The study analysis included 504 telemedical consultation requests. The mean age of the patients was 6.5 ± 5.0 years with 45.5% of the patients being female. Telemedicine was useful in providing a definite diagnosis in 88.3%. The diagnoses were most frequently assigned to the group of infectious skin diseases (28.8%). Referral to a dermatologist was recommended in 11.5%. The requests were answered on the same day in 63.8% of the cases. CONCLUSIONS: The study data shows the great potential of teledermatology to improve access for children with skin diseases to specialized dermatological care. Another advantage is its function as a triage instrument. Since most cases could be managed by teledermatology only, it is possible to reduce the need for an in-person visit to the dermatologist, thus saving resources.

Therapy of necrobiotic xanthogranuloma - case series and review of the literature.

Necrobiotic xanthogranuloma is a rare disease that is part of the non-Langerhans cell histiocytoses. It is characterized by yellowish skin lesions, which are typically periorbitally localized. Extracutaneous manifestations of all organs are possible and can cause potentially life-threatening complications. The disease also belongs to the facultative paraneoplasias and is often associated with paraproteinemia. These aspects should be considered regarding further diagnostics. Due to the rarity of the disease, there are no standardized guidelines for therapy so far. The combination of prednisolone and chlorambucil as well as intravenous immunoglobulins seem to be effective therapeutic options. We present four cases from our clinic as well as the current results of the literature in this mini-review and would like to highlight the therapeutic challenge as well as the need for the development of guidelines.

In vivo visualisation of tattoo particles using multiphoton tomography and fluorescence lifetime imaging.

With increased popularity of decorative tattoos, awareness of tattoo-based dermatological complications has been raised. Health issues include a broad spectrum dominated by allergies and infections. To examine the etiopathology and prognose the outcome of an appropriate therapy, a non-invasive intravital diagnostic approach is indicated. The present pilot study introduces multiphoton tomography equipped with fluorescence lifetime imaging as a diagnostic technique to examine the morphological and metabolic status of tattooed human skin at patient's bedside. The distributing course of tattoo particles can be visualised over time. By providing optical biopsies, inflammation-based alterations in freshly tattooed skin and tattoo complications can be analysed. The study concludes that multiphoton tomography combined with fluorescence lifetime imaging is a suitable technique for in vivo visualisation of tattoo pigments as well as for the assessment of quantitative and qualitative skin changes after injection of tattoo ink into human skin.

Radiofrequency Microneedling for Skin Tightening of the Lower Face, Jawline, and Neck Region.

BACKGROUND: Radiofrequency microneedling (RFMN) treatment is the latest generation of fractional skin rejuvenation methods. OBJECTIVE: To evaluate the efficacy, safety, tolerability and patient satisfaction of RFMN treatment for skin rejuvenation of the lower face and neck area. MATERIALS AND METHODS: A prospective, intraindividual, controlled study. Subjects were treated with a fractional insulated RFMN system with 1 to 3 sessions at intervals of 4 to 12 weeks. Follow-up visits were scheduled on Day 90 and 180 posttreatment. Outcome was assessed by volume analysis of standardized 3-dimensional imaging, and validated clinical scales were rated by the physician, a blinded investigator, and patients. RESULTS: Thirty patients (mean age 55.5 years, Fitzpatrick skin type I-IV) were included. Mean submental volume difference was -4.72 cm3 (±10.07 cm3; range -26.65 cm3 to +16.01 cm3). Physician, blinded investigator, and subjects rated the clinical outcome as highly improved. Mean pain intensity was 5.61/10 on Numeric Rating Scale. Beside slight swelling and redness, no relevant downtime has been observed. CONCLUSION: Fractional RFMN treatment is a safe and effective technique for rejuvenation of the lower face, jawline, and neck region. Sufficient pain management should be provided. Data indicated low to no downtime and high patient satisfaction.

DNA binds to a specific site of the adhesive blood-protein von Willebrand factor guided by electrostatic interactions.

Neutrophils release their intracellular content, DNA included, into the bloodstream to form neutrophil extracellular traps (NETs) that confine and kill circulating pathogens. The mechanosensitive adhesive blood protein, von Willebrand Factor (vWF), interacts with the extracellular DNA of NETs to potentially immobilize them during inflammatory and coagulatory conditions. Here, we elucidate the previously unknown molecular mechanism governing the DNA-vWF interaction by integrating atomistic, coarse-grained, and Brownian dynamics simulations, with thermophoresis, gel electrophoresis, fluorescence correlation spectroscopy (FCS), and microfluidic experiments. We demonstrate that, independently of its nucleotide sequence, double-stranded DNA binds to a specific helix of the vWF A1 domain, via three arginines. This interaction is attenuated by increasing the ionic strength. Our FCS and microfluidic measurements also highlight the key role shear-stress has in enabling this interaction. Our simulations attribute the previously-observed platelet-recruitment reduction and heparin-size modulation, upon establishment of DNA-vWF interactions, to indirect steric hindrance and partial overlap of the binding sites, respectively. Overall, we suggest electrostatics-guiding DNA to a specific protein binding site-as the main driving force defining DNA-vWF recognition. The molecular picture of a key shear-mediated DNA-protein interaction is provided here and it constitutes the basis for understanding NETs-mediated immune and hemostatic responses.

Immunothrombotic Mechanisms Induced by Ingenol Mebutate Lead to Rapid Necrosis and Clearance of Anogenital Warts.

Ingenol mebutate (IM) is highly effective in the treatment of human papillomavirus (HPV)-induced anogenital warts (AGW) leading to fast ablation within hours. However, the exact mode of action is still largely unknown. We performed dermoscopy, in vivo confocal microscopy (CLM), histology, immunohistochemistry, and immunofluorescence to gain insights in mechanisms of IM treatment in AGW. In addition, we used in vitro assays (ELISA, HPV-transfection models) to further investigate in vivo findings. IM treatment leads to a strong recruitment of neutrophils with thrombosis of small skin vessels within 8 h, in a sense of immunothrombosis. In vivo and in vitro analyses showed that IM supports a prothrombotic environment by endothelial cell activation and von Willebrand factor (VWF) secretion, in addition to induction of neutrophil extracellular traps (NETosis). IM superinduces CXCL8/IL-8 expression in HPV-E6/E7 transfected HaCaT cells when compared to non-infected keratinocytes. Rapid ablation of warts after IM treatment can be well explained by the observed immunothrombosis. This new mechanism has so far only been observed in HPV-induced lesions and is completely different from the mechanisms we see in the treatment of transformed keratinocytes in actinic keratosis. Our initial findings indicate an HPV-specific effect, which could be also of interest for the treatment of other HPV-induced lesions. Larger studies are now needed to further investigate the potential of IM in different HPV tumors.

[Early onset of methotrexate-associated lymphoproliferative disorder mimicking Hodgkin's lymphoma]. / Imitation eines Hodgkin-Lymphoms durch Frühmanifestation einer Methotrexat-assoziierten lymphoproliferativen Erkrankung.

Long-term methotrexate (MTX) treatment is known to cause MTX-associated lymphoproliferative disorder (MTX-LPD). A 58-year-old woman with psoriasis vulgaris and pityriasis rubra pilaris was treated with a combination of MTX and ustekinumab for 4 months when she developed generalized lymphadenopathy. The initial histopathological analysis indicated Hodgkin's lymphoma; however, assessing the patient's clinical history revealed the diagnosis of MTX-LPD. To our knowledge, this is the first case of a MTX-LPD after only 4 months of treatment.

Kutane Angiosarkome: molekulare Pathogenese und neue therapeutische Ansätze.

Das kutane Angiosarkom (CAS) ist ein hochaggressiver maligner Tumor mit schlechter Prognose. Das primäre, spontane CAS (pCAS) und das sekundäre, mit einer Bestrahlung oder einem Lymphödem assoziierte CAS (sCAS) unterscheiden sich klinisch sowie molekular. Die Amplifikation/Überexpression von Myc ist ein charakteristisches, wenn auch nicht ausschließliches Merkmal von sCAS, während der Verlust von TP53 selektiv bei pCAS vorkommt. Detaillierte molekulare Analysen mit modernen Multi-Omics-Ansätzen haben gezeigt, dass sowohl pCAS als auch sCAS eine erhebliche molekulare Heterogenität aufweisen. Die betroffenen Gene und ihre molekularen Regulatoren sind mögliche therapeutische Zielstrukturen. Darüber hinaus kann das pCAS in Cluster mit hoher Mutationsrate und/oder ausgeprägten Entzündungssignaturen eingeteilt werden, die als Grundlage für die künftige Stratifizierung von pCAS-Patienten in immuntherapeutischen klinischen Studien dienen können. Während die Aufklärung der der Erkrankung zugrunde liegenden molekularen Veränderungen zügig voranschreitet, verläuft die Entwicklung daraus abgeleiteter neuer Therapien für das CAS jedoch bisher eher langsam. Dennoch wurden einige über die Standardtherapien wie Operation und Radiochemotherapie hinausgehende klinische Studien zu neuen Behandlungsmöglichkeiten initiiert. Dazu gehören zielgerichtete Therapien gegen VEGF und VEGFR1-3 wie Bevacizumab und Pazopanib, sowie ß-Adrenozeptorenblocker wie Propranolol. Derzeit werden auch Immuntherapien entwickelt, unter anderem unter Verwendung der Immuncheckpoint-Inhibitoren Pembrolizumab und Nivolumab sowie des Anti-RANKL-Antikörper Denosumab.

Cutaneous Angiosarcomas: Molecular Pathogenesis Guides Novel Therapeutic Approaches.

Cutaneous angiosarcoma (CAS) is a highly aggressive cancer with a poor prognosis. Primary, spontaneous CAS (pCAS) and secondary, post-irradiation- or lymphedema-associated CAS (sCAS) are clinically, but also molecularly distinct. Myc amplification/overexpression is a characteristic, although not exclusive feature of sCAS, while loss of TP53 selectively occurs in pCAS. Detailed molecular analyses with modern multi-omics approaches have revealed that both pCAS and sCAS exhibit considerable molecular heterogeneity. Affected genes and their molecular regulators including a plethora of microRNAs may serve as future drug targets. Furthermore, pCAS could be subdivided into clusters with high tumor mutational burden and/or high tumor inflammation signatures providing a rationale for the stratification of pCAS patients in future immunotherapeutic clinical studies. Development of novel treatment regimens guided by these molecular alterations, however, cannot fully keep up with the pace of their discovery due to the low incidence of the disease. Nevertheless, beyond conventional surgery and chemoradiotherapy, clinical trials investigating novel treatment options have been initiated including targeted therapies against VEGF and VEGFR1-3 such as bevacizumab and pazopanib, and ß-adrenoreceptor blockers such as propranolol. Finally, immunotherapies are being developed including immune checkpoint inhibitors pembrolizumab and nivolumab as well as anti-RANKL antibody denosumab.