Criteria for melanocytic lesions in LC-OCT.

BACKGROUND: Line-field confocal optical coherence tomography (LC-OCT) is an emerging diagnostic tool with imaging depth reaching ~400 µm and a novel three-dimensional (3D) cube providing cellular resolution. As far as we are aware, there are only a limited number of papers that have reported diagnostic criteria for melanocytic lesions using this technique, and none of them have been multicentric. OBJECTIVES: Our aim was to establish the diagnostic criteria for melanocytic lesions using LC-OCT and identify the most significant architectural and cytologic features associated with malignancy. METHODS: A retrospective evaluation of 80 consecutive melanocytic lesions from a prospective multicentric data set spanning three European centres was conducted. We excluded facial, acral and mucosal lesions from the study. Dermoscopic and LC-OCT images were evaluated by a consensus of four observers. Multivariate logistic regression with backward elimination was employed. RESULTS: The main melanoma diagnostic criteria include detecting >10 pagetoid cells in 3D acquisition, irregular 3D epidermal architecture, disrupted dermoepidermal junction (DEJ) and clefting. Significant risk factors were irregular 3D epidermal architecture, >10 pagetoid cells, dendritic cells at DEJ without underlying inflammation. Novel malignancy criteria in vertical view were DEJ disruption and clefting around atypical melanocyte nests. Exclusive melanoma features were epidermal nests, epidermal consumption, dense dermal nests with atypia. Protective features in the absence of any malignancy indicators were DEJ ring pattern, cobblestone, elongated rete ridges (vertical), well-defined DEJ and wave pattern (vertical). CONCLUSIONS: A series of diagnostic criteria for the identification of melanocytic lesions with LC-OCT have been established. Validation of these criteria in clinical practice through future studies is essential to further establish their utility.

Risk Factors and Innovations in Risk Assessment for Melanoma, Basal Cell Carcinoma, and Squamous Cell Carcinoma.

Skin cancer is the most frequently diagnosed cancer globally and is preventable. Various risk factors contribute to different types of skin cancer, including melanoma, basal cell carcinoma, and squamous cell carcinoma. These risk factors encompass both extrinsic, such as UV exposure and behavioral components, and intrinsic factors, especially involving genetic predisposition. However, the specific risk factors vary among the skin cancer types, highlighting the importance of precise knowledge to facilitate appropriate early diagnosis and treatment for at-risk individuals. Better understanding of the individual risk factors has led to the development of risk scores, allowing the identification of individuals at particularly high risk. These advances contribute to improved prevention strategies, emphasizing the commitment to mitigating the impact of skin cancer.

Understanding the anatomy of dermoscopy of melanocytic skin tumours: Correlation in vivo with line-field optical coherence tomography.

BACKGROUND: Early melanoma detection is the main factor affecting prognosis and survival. For that reason, non-invasive technologies have been developed to provide a more accurate diagnosis. Recently, line-field confocal optical coherence tomography (LC-OCT) was developed to provide an in vivo, imaging device, with deep penetration and cellular resolution in three dimensions. Combining the advantages of conventional OCT and reflectance confocal microscopy, this tool seems to be particularly suitable for melanocytic lesions. OBJECTIVES: The objective of this study was to identify and describe the correlation between specific dermoscopic criteria and LC-OCT features in three dimensions associated with melanocytic lesions. METHODS: Dermoscopic and LC-OCT images of 126 melanocytic lesions were acquired in three different centres. The following dermoscopic criteria have been considered: reticular pattern, dots and globules, structureless areas, blue-whitish veil, regression structures, negative network, homogeneous pattern, streaks and blotches. RESULTS: 69 (55%) benign and 57 (45%) malignant lesions were analysed. A regular reticular pattern was found associated in the 75% of the cases with the presence of elongated rete ridges with pigmented cells along the basal layer, while atypical reticular pattern showed an irregular organization of rete ridges with melanocytic hyperplasia, broadened and fused ridges and elongated nests. Both typical and atypical dots and globules were found associated with melanocytic nests in the dermis or at the dermoepidermal junction (DEJ), as well as with keratin cysts/pseudocysts. Grey globules corresponded to the presence of melanin-containing dermal inflammatory cells (melanophages) within the papillae. Structureless brown/black areas correlated with alterations of the DEJ. We observed the same DEJ alterations, but with the presence of dermal melanophages, in 36% of the cases of blue/white/grey structureless areas. A description of each LC-OCT/dermoscopy correlation was made. CONCLUSIONS: LC-OCT permitted for the first time to perform an in vivo, 3D correlation between dermoscopic criteria and pathological-like features of melanocytic lesions.

Cutaneous manifestations induced by check point inhibitors in 120 melanoma patients-The European MelSkinTox study.

BACKGROUND: Checkpoint inhibitors provide an effective approach for the melanoma treatment. They prolong lymphocyte effects, which explains the cytotoxicity underlying immune-related adverse events (IrAEs). Cutaneous IrAEs affect nearly 40% of PD-1i and 50% of CTLA4i-treated patients. Severe cutaneous irAE do not often occur but could be life-threatening and may persist despite treatment discontinuation. METHODS: We aimed to investigate cutaneous IrAEs in a cohort of patients treated with ICI across Europe in an effort to characterize the reactions in a real-world, phase IV, post-marketing study using a follow-up questionnaire. Data since November 2016 until March 2021 were obtained from the Melskintox database, a European multicentric biobank dedicated to the follow-up of melanoma and cutaneous adverse events, supported by EADO. The dermatoses reported were pooled into four categories: inflammatory dermatosis, bullous diseases, drug-related eruptions and pigmentary diseases. RESULTS: Inflammatory benign dermatoses (n = 63) represented the most common group of reactions (52.5%), followed by drug-related eruptions (n = 24, 20%), pigmentary diseases (n = 23, 19.2%) and bullous diseases (n = 10, 8.3%). Grade II (n = 41, 34.2%) are represented by bullous pemphigoid, eczema, hypodermitis, lichenoid eruption, maculopapular rash, pruritus, psoriasis-like rash, urticarial eruption and vitiligo. Grade III (n = 18, 15.0%) are represented by bullous pemphigoid, lichenoid eruption and rashes. Grade IV (n = 2, 1.7%) is only represented by bullous disease. Most cutaneous IrAEs led to immunotherapy continuation (n = 95, 88.0%). CR is associated with more severe the cutaneous irAEs. We report an average time-to-onset of 208 days and some late-onset events. CONCLUSION: Our study has characterized the clinical spectrum of cutaneous irAEs, their timing and severity and their relationship with tumour response. Grade I-II cutaneous IrAE are easily managed allowing ongoing anticancer treatment. Severe late-onset cutaneous irAE are not uncommon. A dermatological follow-up helps mitigate the risk of life-threatening adverse events. These findings highlight the importance of oncodermatological involvement in management of patients with melanoma receiving immunotherapy.

Line-field confocal optical coherence tomography of cutaneous vascular lesions: Morphological assessment and histopathological correlations.

BACKGROUND: Cutaneous vascular lesions (VLs) are benign or malignant processes involving blood and/or lymphatic vessels, usually readily diagnosed with dermoscopy. However, cases showing unclear clinical/dermoscopic findings may require further investigations. Line-field confocal optical coherence tomography (LC-OCT) is a new, non-invasive imaging technique displaying high resolution and deep penetration. The aim of this study was to describe the LC-OCT features of the most common benign and malignant VLs and to correlate them with histopathological substrates. METHODS: Clinical, dermoscopic, LC-OCT and histopathological images of VLs were retrospectively collected. Detailed LC-OCT description and histopathological correlations were produced for different types of VLs. RESULTS: The study included 71 VLs belonging to 50 caucasian patients [31 (62%) females; median age 56.8 (30-83) years] study lesions included 25 cherry haemangiomas, 15 angiokeratomas, 10 thrombosed haemangiomas, six pyogenic granulomas, five venous lakes, four targetoid haemosiderotic haemangiomas, four Kaposi's sarcomas and two extraungual glomus tumours. LC-OCT detected increased dermal vascularity, assuming different size and shape according to the particular type of VLs. LC-OCT criteria correlated well to established histopathologic findings. CONCLUSION: The results of our preliminary observations indicate that in vivo evaluation with LC-OCT may provide practical clues for the identification of the vascular nature of a lesion and its differential diagnosis.

Prevention and screening of melanoma in Europe: 20 years of the Euromelanoma campaign.

Euromelanoma is a Europe-wide, dermatologist-led organization that campaigns to have a public, scientific, and political impact on raising awareness of the prevention, early diagnosis, and treatment of skin cancer. The organization raises public awareness of skin cancer by providing practical support to participating countries for the roll out of yearly screening campaigns, and then builds on these campaigns by providing resources via its website to educate the general public on key skin cancer prevention measures, risk factors, and the importance of recognizing abnormal lesions through self-examination. Euromelanoma also provides a valuable platform for the scientific community, facilitating collaborations between countries and coordinating the collection of standardized data on the epidemiology, demographic and clinical characteristics, and risk factors for all forms of skin cancer. As our scientific understanding of skin cancer advances, Euromelanoma plays a key role in ensuring that the importance of skin cancer prevention, treatment, and diagnosis remains at the forefront of European and national healthcare policies. Since its creation in 1999, Euromelanoma has continued to evolve, adapt, and expand its approach to achieve these public, scientific, and political goals: the organization now has networks of dermatologists working in over 30 countries and has screened and gathered skin cancer data from around 420 000 subjects. This review highlights these achievements by providing an outline of the history of Euromelanoma and the benefits of the first decade of action and by describing the evolving approach over the past 20 years. Future Euromelanoma projects, which aim to evaluate skin cancer risk in specific populations (outdoor workers, organ transplant recipients, etc.) are also introduced, and current challenges for the Euromelanoma campaign are discussed, including the need to improve reporting of non-melanoma skin cancer cases and to raise awareness of melanoma subtypes, particularly the more difficult to diagnose nodular melanoma form.

Clinicopathological features, MCPyV status and outcomes of Merkel cell carcinoma in solid-organ transplant recipients: a retrospective, multicentre cohort study.

BACKGROUND: The proportion of Merkel cell carcinomas (MCCs) in solid-organ transplant recipients (SOTR) harbouring Merkel cell polyomavirus (MCPyV) is unknown, as are factors affecting their outcomes. OBJECTIVE: To describe clinicopathological features of MCC in SOTR, investigate the tumoral MCPyV-status and identify factors associated with tumour outcomes. METHODS: Retrospective, international, cohort-study. MCPyV-status was investigated by immunohistochemistry and polymerase chain reaction. RESULTS: A total of 30 SOTR and 44 consecutive immunocompetent patients with MCC were enrolled. SOTR were younger at diagnosis (69 vs. 78 years, P < 0.001). Thirty-three percent of SOTR MCCs were MCPyV-positive vs. 91% of immunocompetent MCCs (P = 0.001). Solid-organ transplantation was associated with an increased cumulative incidence of progression (SHR: 3.35 [1.57-7.14], P = 0.002), MCC-specific mortality (SHR: 2.55 [1.07-6.06], P = 0.034) and overall mortality (HR: 3.26 [1.54-6.9], P = 0.002). MCPyV-positivity and switching to an mTOR inhibitor (mTORi) after MCC diagnosis were associated with an increased incidence of progression (SHR: 4.3 [1.5-13], P = 0.008 and SHR: 3.6 [1.1-12], P = 0.032 respectively) in SOTR. LIMITATIONS: Retrospective design and heterogeneity of SOTR cohort. CONCLUSIONS: MCPyV appears to play a less prominent role in the aetiopathogenesis of MCC in SOTR. SOTR have a worse prognosis than their immunocompetent counterparts and switching to an mTORi after the diagnosis of MCC does not improve progression.

Line-field confocal optical coherence tomography of basosquamous carcinoma: a case series with histopathological correlation.

BACKGROUND: Basosquamous carcinoma (BSC) is a rare and potentially aggressive cutaneous neoplasm combining histopathological features of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Line-field confocal optical coherence tomography (LC-OCT) is a new, non-invasive imaging technique featuring excellent resolution and penetration. To date, studies about the use of LC-OCT in the BCC and SCC fields are available, but similar investigations are lacking in the BSC field. OBJECTIVE: The goal of the present study was to identify/describe LC-OCT criteria of BSC. METHODS: Consecutively enrolled BSCs were imaged with dermoscopy and LC-OCT prior to surgical excision. Dermoscopic and LC-OCT images were evaluated, and histopathological slides were reviewed. RESULTS: Six BSCs from six patients [four (66.7%) males and two (33.3%) females; mean age 76.5 (62-96) years] were included. Identified LC-OCT criteria for BSC included BCC-associated (dermal lobules with millefeuille pattern, dilated vessels, bright cells within the epidermis, bright cells within lobules, stromal stretching, stromal brightness) and SCC-associated features (acanthosis, hyperkeratosis, disarranged epidermal architecture, broad strands, elastosis and glomerular vessels). Interruption of the dermal-epidermal junction and ulceration represented overlapping criteria. CONCLUSION: Line-field confocal-OCT is a new promising technique that may support the non-invasive recognition of BSC through the simultaneous detection of BCC-associated and SCC-associated features. We hypothesize that the use of LC-OCT might be helpful not only in the diagnostic setting but also in the follow-up surveillance for an early identification of recurrences. Further larger studies are needed to prove this hypothesis.

Cemiplimab for advanced cutaneous squamous cell carcinoma in kidney transplant recipients.

Background: Kidney transplant recipients (KTR) are at increased risk of cancer due to chronic immunosuppression. Non-melanoma skin cancer has an excess risk of approximately 250 times higher than the general population. Moreover, in solid organ transplant recipients (SOTR) these cancers have a more aggressive behavior, with an increased risk of metastasis and death. Cemiplimab, a human monoclonal IgG4 antibody against programmed cell death (PD-1) has shown considerable clinical activity in metastatic and locally advanced cutaneous squamous cell carcinoma (cSCC) in patients for whom no widely accepted standard of care exists. Cemiplimab has therefore been approved since 2018 for the treatment of advanced cSCC. However, data regarding the use of cemiplimab in SOTR and particularly in KTR are scarce and based on published case reports and small case series. In this study, we report on the real-life outcome of cemiplimab use in a Belgian cohort of seven KTR suffering from advanced cSCC. Objective: To report on the overall response rate (ORR) and safety of cemiplimab in KTR in Belgium. Results: Seven patients suffering from advanced cSCC, treated with cemiplimab, between 2018 and 2022, in Belgium were identified. Three patients were on corticosteroid monotherapy, one patient on tacrolimus monotherapy and three patients were on at least 2 immunosuppressants at start of cemiplimab. The ORR was 42.8%, stable disease was seen in 14.3% and progressive disease was found in 42.8% of the patients, respectively. The median administered number of cycles was 12, interquartile range (IQR) 25-75 [3.5 - 13.5]. All patients were treated with surgery before administration of cemiplimab, 71.4% received additional radiotherapy and only 1 patient was treated with chemotherapy prior to receiving cemiplimab. Biopsy-proven acute renal allograft rejection was observed in one patient, who eventually lost his graft function but showed a complete tumor response to treatment. Low grade skin toxicity was seen in one patient of the cohort. Conclusion: The present case series shows that the use of cemiplimab in KTR with advanced cSCC who failed to respond to previous surgery, chemo - and/or radiotherapy treatment is associated with an ORR of 42.8% with minimal risk of graft rejection (14.3%) and good tolerance.

Advanced cutaneous squamous cell carcinoma of the head in two renal transplanted patients treated with cemiplimab.

It is well known that organ transplant recipients are prone to develop non-melanoma skin cancers, particularly cutaneous squamous cell carcinoma (cSCC). This is explained by the long-term use of immunosuppressants and thus the decrease of the immunosurveillance that protects from developing malignant tumours. Solid organ transplant recipients (SOTRs) are 65-250 times more likely to develop cSCC compared to the general population (Am J Transplant 2017; 17: 2509). Moreover, in these patients cSCCs follow a more aggressive course. Close follow-up and regular skin check-ups by a dermatologist are, therefore, crucial in the management of these patients. When detected early, cSCC can be easily and effectively treated by a simple excision. However, when advanced, outcomes are poor. Immune checkpoints inhibitors (ICIs) have been recently added to our arsenal and represent a breakthrough, having proved to be effective in achieving long-term responses. We, hereby, present two cases of difficult-to-treat cSCCs in renal transplanted patients.

Position statement on classification of basal cell carcinomas. Part 1: unsupervised clustering of experts as a way to build an operational classification of advanced basal cell carcinoma based on pattern recognition.

BACKGROUND: No simple classification system has emerged for 'advanced basal cell carcinomas', and more generally for all difficult-to-treat BCCs (DTT-BCCs), due to the heterogeneity of situations, TNM inappropriateness to BCCs, and different approaches of different specialists. OBJECTIVE: To generate an operational classification, using the unconscious ability of experts to simplify the great heterogeneity of the clinical situations into a few relevant groups, which drive their treatment decisions. METHOD: Non-supervised independent and blinded clustering of real clinical cases of DTT-BCCs was used. Fourteen international experts from different specialties independently partitioned 199 patient cases considered 'difficult to treat' into as many clusters they want (≤10), choosing their own criteria for partitioning. Convergences and divergences between the individual partitions were analyzed using the similarity matrix, K-mean approach, and average silhouette method. RESULTS: There was a rather consensual clustering of cases, regardless of the specialty and nationality of the experts. Mathematical analysis showed that consensus between experts was best represented by a partition of DTT-BCCs into five clusters, easily recognized a posteriori as five clear-cut patterns of clinical situations. The concept of 'locally advanced' did not appear consistent between experts. CONCLUSION: Although convergence between experts was not granted, this experiment shows that clinicians dealing with BCCs all tend to work by a similar pattern recognition based on the overall analysis of the situation. This study thus provides the first consensual classification of DTT-BCCs. This experimental approach using mathematical analysis of independent and blinded clustering of cases by experts can probably be applied to many other situations in dermatology and oncology.

Position statement on classification of basal cell carcinomas. Part 2: EADO proposal for new operational staging system adapted to basal cell carcinomas.

BACKGROUND: No simple staging system has emerged for basal cell carcinomas (BCCs), since they do not follow the TNM process, and practitioners failed to agree on simple clinical or pathological criteria as a basis for a classification. Operational classification of BCCs is required for decision-making, trials and guidelines. Unsupervised clustering of real cases of difficult-to-treat BCCs (DTT-BCCs; part 1) has demonstrated that experts could blindly agree on a five groups classification of DTT-BCCs based on five patterns of clinical situations. OBJECTIVE: Using this five patterns to generate an operational and comprehensive classification of BCCs. METHOD: Testing practitioner's agreement, when using the five patterns classification to ensure that it is robust enough to be used in the practice. Generating the first version of a staging system of BCCs based on pattern recognition. RESULTS: Sixty-two physicians, including 48 practitioners and the 14 experts who participated in the generation of the five different patterns of DTT-BCCs, agreed on 90% of cases when classifying 199 DTT-BCCs cases using the five patterns classification (part 1) attesting that this classification is understandable and usable in practice. In order to cover the whole field of BCCs, these five groups of DTT-BCCs were added a group representing the huge number of easy-to-treat BCCs, for which sub-classification has little interest, and a group of very rare metastatic cases, resulting in a four-stage and seven-substage staging system of BCCs. CONCLUSION: A practical classification adapted to the specificities of BCCs is proposed. It is the first tumour classification based on pattern recognition of clinical situations, which proves to be consistent and usable. This EADO staging system version 1 will be improved step by step and tested as a decision tool and a prognostic instrument.

Line-field confocal optical coherence tomography for actinic keratosis and squamous cell carcinoma: a descriptive study.

BACKGROUND: Early and accurate diagnosis of cutaneous squamous cell carcinomas (SCCs) and actinic keratoses (AK) is fundamental to reduce their associated morbidity and to select the correct treatment. Line-field confocal optical coherence tomography (LC-OCT) is a new imaging device that can characterize healthy skin and basal cell carcinoma, but no large studies on keratinocyte cell tumours have yet been published. AIM: To identify and describe LC-OCT criteria associated with SCC and AK, and to compare LC-OCT findings in these tumours. METHODS: A retrospective observational multicentre study was conducted. Lesions were imaged with the LC-OCT device before surgery and examined histologically. LC-OCT criteria for AK/SCC were identified and their presence was evaluated in all study lesions. Univariate and multivariate analyses were performed to compare AK and SCCs, and to investigate differences between in situ and invasive tumours. RESULTS: In total, 158 patients with 50 AK and 108 SCCs (62 in situ and 46 invasive) were included. Cytological and architectural alterations were found in most lesions, and differences were found between AK and SCCs. Although the visualization of the dermoepidermal junction (DEJ) was often hampered by hyperkeratosis and acanthosis, an outlined DEJ without broad strands was observed in almost all AK and almost all in situ SCCs, but in only three invasive SCCs (P < 0.001) when the DEJ was detectable. CONCLUSION: Our results suggest that LC-OCT can help clinicians in the identification of AK and SCC and their differentiation, providing a real-time and noninvasive examination. Further studies are needed to confirm our data.