Tolerability and Safety of Miltefosine for the Treatment of Cutaneous Leishmaniasis.

Miltefosine, an orally administered drug, is an important component of the therapeutic arsenal against visceral and mucosal forms of leishmaniasis. However, data regarding the safety and tolerability of miltefosine treatment for cutaneous leishmaniasis (CL) are relatively limited. The aim of this study was to evaluate the tolerability, safety, and adverse events (AEs) of miltefosine treatment in patients with CL. In this cohort study, we reviewed the medical records of all miltefosine-treated patients between 1 January 2016 and 31 December 2022, at Israel Defense Forces military dermatology clinics and the dermatology and Tropical Medicine Clinics at Chaim Sheba Medical Center, Ramat-Gan, Israel. A total of 68 patients (54 males, 79%) with a median age of 30.3 ± 15.6 years (range: 18-88) were included in this study. Leishmania species were identified as L. major (n = 37, 54.4%), L. tropica (n = 12, 17.6%), L. braziliensis (n = 18, 26.5%), and L. infantum (n = 1, 1.5%) using polymerase chain reaction (PCR). Miltefosine tablets were administered orally at a dose of 50 mg, three times daily, for 28 days. Overall, 44 patients (65%) completed the 28-day treatment, and the remaining patients required dose reduction or early discontinuation of treatment. AEs (of any degree) were common, reported in 91% of patients. Both previously reported and previously unreported AEs were documented. Gastrointestinal symptoms (66.1%) and malaise (23.5%) typically occurred during the first two weeks of treatment and tended to subside. Other AEs, including acute renal failure (20.6%), sudden and severe pleuritic chest pain (7.6%), acne exacerbation (11.8%), suppuration of CL lesions (17.8%), and AEs related to the male genitourinary system (39.6% of males), typically occurred towards the end of treatment. The latter included testicular pain, epididymitis, diminution or complete absence of ejaculate, inability to orgasm, and impotence. Severe AEs necessitated treatment discontinuation (29.4%) or hospitalization (10.3%). URTI-like symptoms, arthritis, cutaneous eruption, pruritus, and laboratory abnormalities were also observed. Overall, the cure rate (for all patients combined) evaluated 3 months after the completion of treatment was 60%. The tolerability of miltefosine treatment for CL is low. Close clinical and laboratory monitoring is required during treatment, as severe AEs are not uncommon. As new insights regarding its toxicities emerge, further studies are required to define the role of miltefosine in the treatment of CL.

The role of piperacillin/tazobactam in the treatment of Hidradenitis suppurativa.

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease. Most patients with moderate-to-severe disease require long-term antibiotic treatment, or biologic treatments to control their disease. Despite these interventions, relapses are common. This study evaluated the effectiveness of piperacillin/tazobactam treatment in patients with Hurley stage II and III HS who experienced disease flares and did not respond to conventional antibiotic and biologic treatment. Methods: Patients with HS hospitalized at the Department of Dermatology, Sheba Medical Center between August 2021 and January 2023 were retrospectively analyzed. Results: A cohort of ten such patients were treated with piperacillin/tazobactam for 6-21 days. Eight (80%) and two (20%) patients respectively demonstrated 2- and 1-grade improvements, from their baseline HS-Physician Global Assessment score. During the follow-up period, nine patients were monitored. HS Clinical Response (HiSCR) was achieved in six (66.7%) and five (55.6%) patients at the 3- and 6-month follow-up visits, respectively. Conclusions: In conclusion, Piperacillin/tazobactam emerges as a promising therapeutic option for disease flare-up in patients with Hurley stage II and III HS who do not respond to conventional treatment. Thus, piperacillin/tazobactam should be considered as crisis therapy for this patient subset.

A decision support system for the detection of cutaneous fungal infections using artificial intelligence.

Cutaneous fungal infections are one of the most common skin conditions, hence, the burden of determining fungal elements upon microscopic examination with periodic acid-Schiff (PAS) and Gomori methenamine silver (GMS) stains, is very time consuming. Despite some morphological variability posing challenges to training artificial intelligence (AI)-based solutions, these structures are favored potential targets, enabling the recruitment of promising AI-based technologies. Herein, we present a novel AI solution for identifying skin fungal infections, potentially providing a decision support system for pathologists. Skin biopsies of patients diagnosed with a cutaneous fungal infection at the Sheba Medical Center, Israel between 2014 and 2023, were used. Samples were stained with PAS and GMS and digitized by the Philips IntelliSite scanner. DeePathology® STUDIO fungal elements were annotated and deemed as ground truth data after an overall revision by two specialist pathologists. Subsequently, they were used to create an AI-based solution, which has been further validated in other regions of interests. The study participants were divided into two cohorts. In the first cohort, the overall sensitivity of the algorithm was 0.8, specificity 0.97, F1 score 0.78; in the second, the overall sensitivity of the algorithm was 0.93, specificity 0.99, F1 score 0.95. The results obtained are encouraging as proof of concept for an AI-based fungi detection algorithm. DeePathology® STUDIO can be employed as a decision support system for pathologists when diagnosing a cutaneous fungal infection using PAS and GMS stains, thereby, saving time and money.

Application of a natural language processing artificial intelligence tool in psoriasis: A cross-sectional comparative study on identifying affected areas in patients' data.

Psoriasis is an immune-mediated skin disease affecting approximately 3% of the global population. Proper management of this condition necessitates the assessment of the body surface area and the involvement of nails and joints. The integration of natural language processing with electronic medical records (EMRs) has recently shown promise in advancing disease classification and research. This study evaluates the performance of ChatGPT-4, a commercial artificial intelligence platform, in analyzing unstructured EMR data of psoriasis patients, particularly in identifying affected body areas. The study analyzed EMR data from 94 patients treated at the Dermatology Department and Psoriasis Outpatient Clinic of Sheba Medical Center between 2008 and 2022. The data were processed using the ChatGPT-4 interface to identify and report the body areas affected by psoriasis. These identified areas were then categorized, and the accuracy of ChatGPT-4's analysis was compared with that of a senior dermatologist. The results revealed that the dermatologist identified 477 psoriasis-affected body areas. ChatGPT-4 accurately recognized 443 (92.8%) of these areas, missed 34, and incorrectly identified 30 areas as affected. From 94 cases, nail involvement was detected in 32 cases (34.0%), with ChatGPT-4 correctly identifying 29 cases. Joint involvement was noted in 25 cases (26.6%), with 24 correctly identified using ChatGPT-4. Complete accuracy was achieved in 54 cases (57.4%), although inaccuracies were observed in 40 cases (42.6%). We found that cases with more characters, words, or identified body areas were more prone to errors, suggesting that increased data complexity heightens the likelihood of inaccuracies in artificial intelligence analysis. ChatGPT-4 demonstrated high performance in analyzing detailed and complex unstructured EMR data from patients with psoriasis, effectively identifying involved body areas, including nails and joints. This highlights the potential of NLP algorithms to enhance the analysis of unstructured EMR data for both clinical follow-up and research purposes.

Comparison of Intralesional Sodium Stibogluconate versus Intralesional Meglumine Antimoniate for the Treatment of Leishmania major Cutaneous Leishmaniasis.

Israel is endemic for Old-World cutaneous leishmaniasis. The most common species is Leishmania major. However, the available treatment options are limited. This study's objective was to compare the authors' experience with different antimony intralesional treatments of Leishmania major cutaneous leishmaniasis. A retrospective evaluation was undertaken for cases of Leishmania major cutaneous leishmaniasis treated by pentavalent antimony in a university-affiliated medical centre in Israel. The previous treatment of intralesional sodium stibogluconate (Pentostam®) was compared with the current treatment of meglumine antimoniate (Glucantime®). One hundred cases of cutaneous leishmaniasis were treated during the study period, of whom 33 were treated with intralesional sodium stibogluconate and 67 were treated with intralesional meglumine antimoniate. The patients were 78 males and 22 females, mean age 24 (range 10-67) and there was a total of 354 skin lesions. Within 3 months from treatment, 91% (30/33) of the intralesional sodium stibogluconate group and 88% (59/67) of the intralesional meglumine antimoniate group had complete healing of the cutaneous lesions after an average of 3 treatment cycles (non-statistically significant). In conclusion, the 2 different medications have the same efficacy and safety for treating cutaneous leishmaniasis. Pentavalent antimoniate intralesional infiltration treatment is safe, effective, and well tolerated with minimal side effects for Old-World cutaneous leishmaniasis.

[COMPREHENSIVE GUIDELINES AND INDICATIONS FOR DIGITAL MONITORING OF PATIENTS AT HIGH-RISK FOR MELANOMA: A POSITION PAPER BY THE ISRAELI ASSOCIATION FOR DERMATOLOGY].

INTRODUCTION: Early detection may lead to reduced morbidity and mortality from melanoma. This study aims to establish guidelines for selecting patients suitable for digital monitoring of skin lesions. METHODS: A literature review was conducted, followed by consensus among experts appointed by the Israeli Dermatology Association. RESULTS: Two effective methods for early melanoma diagnosis were identified: Total-body photography (TBP) and digital dermoscopy. TBP involves capturing clinical images of the entire skin area for long-term monitoring (6-12 months). Digital dermoscopy focuses on close-up images of distinct lesions for short-term monitoring (3-4 months). Various risk factors for melanoma were identified, including genetic and familial factors, as well as demographic and phenotypic characteristics. Based on these risk factors and feasibility of clinical follow-up, a comprehensive list of indications for TBP was developed, categorized into three groups based on the expected level of benefit. Digital dermoscopy surveillance is recommended for patients with flat or slightly raised skin lesions showing dermoscopic features that do not definitively indicate melanoma. DISCUSSION: TBP significantly improves early melanoma detection, enhancing sensitivity and specificity while reducing unnecessary biopsies. However, due to its high cost and limited coverage by the Israeli public health care system, prioritizing patients who would benefit most from TBP is crucial. The compiled list of indications aligns with international recommendations and provides further details within the article.

Epidemiological and Clinical Characteristics of Adult and Pediatric Patients with Chronic Spontaneous Urticaria.

Chronic spontaneous urticaria (CSU) is when lesions occur for ≥6 weeks. However, its underlying mechanism remains unclear. CSU prevalence is similar in adult and pediatric patients; nevertheless, few data are available on CSU characteristics in pediatric patients. We aimed to describe the epidemiology, clinical features, and treatment approach of CSU in pediatrics and adults. In this cross-sectional study, 193 patients with CSU were treated at the Sheba Medical Center, Israel, in 2009-2022. The information collected includes age at diagnosis, reported triggers, atopic co-morbidities, autoimmune co-morbidities, treatments and their response, family background, laboratory tests, and follow-up duration. The study group was divided into pediatrics (aged ≤ 18) and adults. Metabolic syndrome was most prevalent in adults as against atopy in pediatrics. Autoimmune co-morbidities were observed in 34.7% and 34.8% of adults and pediatrics, respectively. Inflammatory bowel disease and thyroid disease were the most common in pediatrics and adults, respectively. Systemic treatments other than antihistamines were administered more frequently in adults. Adults with autoimmune disease required second-line treatment with immunomodulators compared to those without it. Co-morbidities were more common in adults than in pediatrics. Patients with autoimmune co-morbidities may be more challenging to manage; thus, escalation to biologics should be considered soon.

Diagnostic delay, comorbid hidradenitis suppurativa and the prognostic value of bacterial culture in folliculitis decalvans: A cohort study.

BACKGROUND: Folliculitis decalvans (FD) is a type of primary neutrophilic cicatricial alopecia often leading to irreversible hair loss. Data on its epidemiology, clinical features, outcomes, and prognostic factors are limited. OBJECTIVE: To evaluate a cohort of patients with FD and identify characteristics of severe disease and prognostic factors which impede remission. PATIENTS AND METHODS: This retrospective cohort study included 192 patients diagnosed with FD and followed for at least six months at a tertiary center between 2010 and 2020. RESULTS: There was a diagnostic delay averaging 22.2 (± 29.7) months. Comorbid follicular occlusion disorders were common. Bacterial cultures were positive in 45.6% of the cases, with Staphylococcus (S.) aureus being the most common pathogen. Severe disease was associated with comorbid hidradenitis suppurativa and a positive bacterial culture, particularly S. aureus. 50.7% of patients experienced complete remission: 32% within the first six months of treatment and 18.7% later during follow-up. Relapses were frequent. Negative prognostic factors for achieving remission included younger age and a positive bacterial culture. CONCLUSIONS: There is a need for the education of dermatologists to reduce the diagnostic delay. Screening FD patients for comorbid hidradenitis suppurativa and obtaining bacterial cultures is important for treatment planning.

The Implications of a Dermatopathologist's Report on Melanoma Diagnosis and Treatment.

An accurate and comprehensive histopathology report is essential for cutaneous melanoma management, providing critical information for accurate staging and risk estimation and determining the optimal surgical approach. In many institutions, a review of melanoma biopsy specimens by expert dermatopathologists is considered a necessary step. This study examined these reviews to determine the critical primary histopathology Breslow score in which a histopathology review would be most beneficial. Histopathology reports of patients referred to our institute between January 2011 and September 2019 were compared with our in-house review conducted by an expert dermatopathologist. The review focused on assessing fundamental histologic and clinical prognostic features. A total of 177 specimens underwent histopathology review. Significant changes in the Breslow index were identified in 103 cases (58.2%). Notably, in many of these cases (73.2%), the revised Breslow was higher than the initially reported score. Consequently, the T-stage was modified in 51 lesions (28.8%). Substantial discordance rates were observed in Tis (57%), T1b (59%), T3a (67%) and T4a (50%) classifications. The revised histopathology reports resulted in alterations to the surgical plan in 15.3% of the cases. These findings emphasize the importance of having all routine pathologies of pigmented lesions referred to a dedicated cancer center and reviewed by an experienced dermatopathologist. This recommendation is particularly crucial in instances where the histopathology review can potentially alter the diagnosis and treatment plan, such as in melanoma in situ and thinner melanomas measuring 0.6-2.2 mm in thickness. Our study highlights the significant impact of histopathology reviews in cutaneous melanoma cases. The observed changes in Breslow scores and subsequent modifications in T-stage classification underline the need for thorough evaluation by an expert dermatopathologist, especially in cases of melanoma in situ and thin melanomas. Incorporating such reviews into routine practice within dedicated cancer centers can improve diagnostic accuracy and guide appropriate treatment decisions, ultimately leading to better patient outcomes.

Mycosis Fungoides in Solid-Organ Transplant Recipients: A Multicenter Retrospective Cohort Study.

BACKGROUND: Mycosis fungoides (MF) in solid-organ transplant recipients (SOTRs) is rare, with limited data on disease characteristics. OBJECTIVE: The aim was to study the characteristics of MF in SOTRs with an emphasis on the immunosuppressive therapy. METHODS: A retrospective cohort of patients diagnosed with MF, who were also SOTRs, were followed at 3 cutaneous lymphoma outpatient clinics, between January 2010 and February 2022. RESULTS: Ten patients were included (7 male; median ages at transplantation and at diagnosis of MF were 33 and 48 years, respectively; 40% were diagnosed before the age of 18 years). Median time from transplantation to diagnosis of MF was 8 years (range 0.5-22). Transplanted organs and immunosuppressive treatments included: liver (n = 5; 4 treated with tacrolimus, 1 with tacrolimus and prednisone), kidney (n = 3), liver and kidney (n = 1), and heart (n = 1), all treated with mycophenolic acid, tacrolimus, and prednisone. Nine had early-stage MF (IA - 4, IB - 5; 40% with early folliculotropic MF), treated with skin-directed therapies, in 2 combined with acitretin, achieving partial/complete response. One patient had advanced-stage MF (IIIA) with folliculotropic erythroderma, treated with ultraviolet A and narrow-band ultraviolet B with acitretin, achieving partial response. Immunosuppression was modified in 3. At last follow-up (median 4 years, range 1-8), no stage progression was observed; 5 had no evidence of disease, 5 had active disease (IA/IB - 4, III - 1). CONCLUSIONS: MF in SOTRs is usually diagnosed at an early stage, with overrepresentation of folliculotropic MF, and of children. Immunosuppressive therapy alterations, not conducted in most patients, should be balanced against the risk of organ compromise/rejection. Disease course was similar to MF in immunocompetent patients, during the limited time of follow-up.

Psori Silk in Mild to Moderate Psoriasis: A Randomized Phase I-II Trial Study.

In patients with mild to moderate psoriasis, topical corticosteroids are usually the first-line of treatment; however, they are not suitable for long-term use. The purpose of this study was to assess the efficacy and safety of a multi-fruit-and-vegetable compound, Psori Silk, in the treatment of patients with psoriasis. This was a randomized double-blind trial comprising 12 weeks of treatment with Psori Silk versus a vehicle, and a 4-week follow-up. The primary endpoint was 50% reduction in the modified Psoriasis Area and Severity Index (MPASI 50) score at week 12, while the secondary endpoint was quality of life assessment using the Dermatology Life Quality Index (DLQI). The Psori Silk group consisted of 23 patients with 34 lesions to be treated versus 22 patients in the vehicle group with 36 lesions. The MPASI 50 score was observed in 59% patients in the active group versus 22.7% patients in the vehicle group (P < 0.001). A mean 33% DLQI improvement was observed in 65.2% patients in the active group versus 27.2% patients in the vehicle group (P < 0.001). Mild and temporary discomfort at the site of application was reported in 39% patients in the active group versus 23% patients in the vehicle group. Psori silk appears to be an effective and safe treatment option for mild to moderate plaque psoriasis.

Bath psoralen plus ultraviolet-A photochemotherapy for chronic graft-versus-host disease: a retrospective cohort study.

BACKGROUND: Chronic graft-versus-host disease is a severe complication of allogeneic stem cell and bone marrow transplantation. First-line immunosuppressive agents, such as steroids, are used to prevent this disease; however, they have multiple side effects. Therefore, bath psoralen plus ultraviolet-A (PUVA) is an alternative second-line treatment. This study aimed to evaluate the clinical efficacy of bath PUVA for managing chronic graft-versus-host disease. METHODS: This retrospective, case-control study included 14 patients with extensive cutaneous chronic graft-versus-host disease, resistant to systemic corticosteroid, treated with bath PUVA. Major and partial responses were defined as clinical improvements of >70% and 50-70%, respectively. We analyzed the graft-versus-host disease clinical presentation and timing after allogeneic stem cell and bone marrow transplantation, bath PUVA doses, background diseases, additional treatments, and adverse effects. RESULTS: We observed eight major (three lichenoid and five sclerodermatoid) and six partial (three lichenoid and three sclerodermatoid) responses after a mean of 28 treatment sessions. After 6 to 25 months, four of the eight patients with sclerodermatoid lesions and all those with lichenoid lesions experienced relapse but responded to additional treatment cycles. CONCLUSIONS: Bath PUVA is well-tolerated and effective for extensive cutaneous chronic graft-versus-host disease. It allows rapid tapering of adjuvant immunosuppressants; however, most patients require prolonged maintenance phototherapy.

Biological treatment for bullous pemphigoid.

Background: Bullous pemphigoid (BP) is the most common autoimmune subepidermal bullous disease. Topical or systemic corticosteroids are often used as the first-line treatment. However, long-term corticosteroid use may lead to significant side effects. Therefore, various adjuvant immunosuppressant therapies are used as steroid-sparing agents, with accumulating reports of biological treatments for severely recalcitrant BP. Objective: To describe the clinical and immunological features of a series of patients with recalcitrant BP treated with immunobiological therapies. To assess the efficacy and safety of their therapies. Methods: Patients receiving biological treatment for BP from two centers were assessed. Here, we described the clinical, immunopathological, and immunofluorescence findings of adult patients with BP and analyzed the clinical response and adverse events associated with various biological therapies. Results: We identified nine eligible patients treated with rituximab (seven), omalizumab (three), or dupilumab (one). The mean age at diagnosis was 60.4 years, the average BP duration before biologic initiation was 1.9 years, and the average previous treatment failure was 2.11 therapies. The mean follow-up period from the first biological treatment to the last visit was 29.3 months. Satisfactory response, defined as clinical improvement, was achieved in 78% (7) of the patients, and total BP clearance was achieved in 55% (5) of the patients at the last follow-up visit. Additional rituximab courses improved the disease outcomes. No adverse events were reported. Conclusions: Efficient and safe novel therapies can be considered in recalcitrant steroid-dependent BP non-responsive to conventional immunosuppressant therapies.

Coexistence of malignancies in pemphigus vulgaris.

Pemphigus vulgaris (PV) is a rare autoimmune intraepidermal bullous disease. PV has a major effect on morbidity as well as quality of life. There is sparse literature regarding the association between pemphigus vulgaris (PV) and comorbid malignancies. In this study we aimed to assess the risk of malignancy in a cohort of patients with PV and characterize PV-associated malignancies. Data were collected from two tertiary referral centers between the years 2008 and 2019 and compared with the national cancer registry. Of 164 patients with PV, 19 were diagnosed with malignancy: seven prior to PV diagnosis and 12 after. All cancers, solid and hematological, displayed higher incidences compared to the general population (p <0.001). In conclusion, we demonstrated higher rates of malignancies among patients with PV than in the general population. These observations suggest the need for careful assessment and follow up of patients with PV, given the possibility of associated malignancies.

White epidermal nevus as an early sign of tuberous sclerosis complex-A case series.

Tuberous sclerosis complex (TSC) is a rare genetic disease with neurocutaneous manifestations, often presenting initially to the dermatology clinic. We report a cohort of neonates who presented with a novel finding of white epidermal nevus and were eventually diagnosed with TSC. White epidermal nevus may be yet another dermatological finding that may aid in the early diagnosis of TSC.

Bullous pemphigoid and dipeptidyl peptidase-4 inhibitors: evaluation of clinical course and treatment response.

BACKGROUND: Dipeptidyl peptidase-4 inhibitors (DPP4is), drugs used to treat type 2 diabetes mellitus (DM2), show a significant association with bullous pemphigoid (BP) development. OBJECTIVES: To evaluate the clinical course and development of BP among patients with DM2 treated with DPP4is. METHODS: This retrospective cohort study included all the patients with BP and comorbid DM2 who visited Sheba Medical Center during 2015-2020. RESULTS: Among 338 patients with BP, 153 were included in our study. In 92 patients, BP diagnosis was attributed to the use of DPP4is. The patients with DPP4i-associated BP had fewer neurological and cardiovascular comorbidities and higher blistered body surface area (BSA) at first presentation, with noticeable upper and lower limb involvement. These patients were younger and more responsive to treatment, with a greater reduction in their BSA score after 2 months of treatment. CONCLUSIONS: The clinical features of patients with BP treated with DPP4is were initially more severe; however, during follow-up, a marked clinical improvement was noticed, especially among patients who had ceased the drug. Therefore, although withdrawal of the drug may not impose disease remission, it can alleviate the disease course and avert the need for treatment escalation.

Cutaneous Leishmaniasis Caused by Leishmania infantum, Israel, 2018-2021.

Cutaneous leishmaniasis (CL) is endemic to Israel. Previously, CL caused by Leishmania infantum had been reported in Israel only once (in 2016). We report 8 L. infantum CL cases; 7 occurred during 2020-2021. None of the patients had systemic disease. L. infantum CL may be an emerging infection in Israel.

Prevalence, Spectrum and Clinical Implications of Malignancies in Patients with Bullous Pemphigoid.

Current research on the malignancy rate and spectrum of malignancies in patients with bullous pemphigoid is contradictory. The aims of this study were to determine the prevalence and spectrum of malignancy in patients with bullous pemphigoid and to compare demographic, clinical, therapeutic and outcome data between bullous pemphigoid patients with and without malignancy. This retrospective cohort study enrolled 335 patients (194 women and 141 men; mean age at diagnosis of bullous pemphigoid 77.5 ± 12 years) followed up at an Israeli tertiary centre between January 2009 and December 2019: 107 (32%) had malignancy and 228 (68%) did not. Malignancy occurred before and after bullous pemphigoid diagnosis in 82 (77%) and 25 (23%) patients, respectively. Bullous pemphigoid patients with cancer were older (p = 0.02) and had a higher mortality rate (p < 0.0001) than those without malignancy. The 2 groups did not differ in terms of sex, comorbidities, or clinical characteristics. Those who developed malignancy before bullous pemphigoid were younger than those who developed malignancy after bullous pemphigoid (mean age 69.3 vs 82.4 years, p < 0.0001). Overall malignancy rates did not differ between patients with bullous pemphigoid and the general population; therefore, comprehensive malignancy workup may be unnecessary. However, patients with bullous pemphigoid had a greater risk of melanoma (10.7% vs 4.3%, p = 0.0005); therefore, routine skin screening may be recommended.

Primary Melanoma miRNA Trafficking Induces Lymphangiogenesis.

Melanoma, the deadliest cutaneous tumor, initiates within the epidermis; during progression, cells invade into the dermis and become metastatic through the lymphatic and blood system. Before melanoma cell invasion into the dermis, an increased density of dermal lymphatic vessels is observed, generated by a mechanism which is not fully understood. In this study, we show that, while at the primary epidermal stage (in situ), melanoma cells secrete extracellular vesicles termed melanosomes, which are uptaken by dermal lymphatic cells, leading to transcriptional and phenotypic pro-lymphangiogenic changes. Mechanistically, melanoma-derived melanosomes traffic mature let-7i to lymphatic endothelial cells, which mediate pro-lymphangiogenic phenotypic changes by the induction of type I IFN signaling. Furthermore, transcriptome analysis upon treatment with melanosomes or let-7i reveals the enhancement of IFI6 expression in lymphatic cells. Because melanoma cells metastasize primarily via lymphatic vessels, our data suggest that blocking lymphangiogenesis by repressing either melanosome release or type I IFN signaling will prevent melanoma progression to the deadly metastatic stage.