Operational classification of cutaneous squamous cell carcinomas based on unsupervised clustering of real cases by experts.

BACKGROUND: There is currently no staging system for cutaneous squamous cell carcinoma (cSCC) that is adapted to decision-making and universally used. Experts have unconscious ability to simplify the heterogeneity of clinical situations into a few relevant groups to drive their therapeutic decisions. Therefore, we have used unsupervised clustering of real cases by experts to generate an operational classification of cSCCs, an approach that was successful for basal cell carcinomas. OBJECTIVE: To generate a consensual and operational classification of cSCCs. METHOD: Unsupervised independent clustering of 248 cases of cSCCs considered difficult-to-treat. Eighteen international experts from different specialties classified these cases into what they considered homogeneous clusters useful for management, each with freedom regarding clustering criteria. Convergences and divergences between clustering were analysed using a similarity matrix, the K-mean approach and the average silhouette method. Mathematical modelling was used to look for the best consensual clustering. The operability of the derived classification was validated on 23 new practitioners. RESULTS: Despite the high heterogeneity of the clinical cases, a mathematical consensus was observed. It was best represented by a partition into five clusters, which appeared a posteriori to describe different clinical scenarios. Applicability of this classification was shown by a good concordance (94%) in the allocation of cases between the new practitioners and the 18 experts. An additional group of easy-to-treat cSCC was included, resulting in a six-group final classification: easy-to-treat/complex to treat due to tumour and/or patient characteristics/multiple/locally advanced/regional disease/visceral metastases. CONCLUSION: Given the methodology based on the convergence of unguided intuitive clustering of cases by experts, this new classification is relevant for clinical practice. It does not compete with staging systems, but they may complement each other, whether the objective is to select the best therapeutic approach in tumour boards or to design homogeneous groups for trials.

Efficacy of sonic hedgehog inhibitors rechallenge, after initial complete response in recurrent advanced basal cell carcinoma: a retrospective study from the CARADERM database.

BACKGROUND: Smoothened (SMO) inhibitors, blocking the sonic hedgehog pathway, have been approved for advanced basal cell carcinoma (aBCC). Safety analyses reveal a high rate of adverse events (AEs) and, most of the time, vismodegib is most commonly stopped when the best overall response is reached. The long-term evolution of aBCC after vismodegib discontinuation is poorly described. The aim of this study is to evaluate the efficacy and safety of the SMO inhibitors (SMOis) available (vismodegib and sonidegib) following rechallenge after complete response (CR) following an initial treatment by vismodegib. MATERIALS AND METHODS: This real-life, retrospective, multicenter and descriptive study is based on an extraction from the CARADERM accredited database, including 40 French regional hospitals, of patients requiring BCC systemic treatment. RESULTS: Of 303 patients treated with vismodegib, 110 achieved an initial CR. The vast majority of these patients (98.2%) stopped vismodegib, notably due to poorly tolerated AEs. The CARADERM database provided a median follow-up of 21 months (13.5-36.0 months) after CR. Of the 110 patients, 48.1% relapsed after a median relapse-free survival of 24 months (13.0-38.0 months). Among them, 35 patients were retreated by an SMOi and the overall response rate was 65.7% (34.3% of CR and 31.4% of partial response). The median duration of retreatment was 6.0 months (4.0-9.5 months). CONCLUSION: Our real-life study, carried out on patients with complex clinical pictures, shows that after treatment discontinuation, 48.1% of patients achieved CR relapse within an average of 24 months (13.0-38.0 months). It emphasized that even though rechallenge can be considered as a therapeutic option, efficacy seems to decrease, suggesting the development of resistance mechanisms.

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.

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.

Penoscrotal Paget's disease.

Paget's disease (PD) denotes an initially intra-epidermal adenocarcinoma that can later invade the dermis and metastasise. Among the extramammary forms of PD (EMPD), penoscrotal presentations are rarer than the vulvar and perianal forms. Once diagnosis has been confirmed by histopathological examination, a search for associated neoplasia must be conducted, although penoscrotal EMPD is less frequently associated with underlying neoplasia than mammary PD (MPD). The associated cancer most often involves a neighbouring organ, with prostate cancer being the most common, or in some cases consists of underlying cutaneous adnexal tumours. First-line therapy consists of surgical excision. Alternatives to surgery (imiquimod, CO2 laser vaporisation, dynamic phototherapy) may be considered in certain cases.

Actinic cheilitis: a systematic review of treatment options.

Actinic cheilitis is a premalignant condition that can progress to squamous cell carcinoma with a higher propensity for metastasis than cutaneous squamous cell carcinoma. Optimal treatment for actinic cheilitis has not been established, and evidence-based estimates of clinical cure in the dermatology literature are limited. Here, we review and synthesize outcome data published for patients with actinic cheilitis after treatment with various modalities. A systematic review was conducted in MEDLINE, Embase and the Cochrane library for English, French and German-language studies and references of included articles from inception to 20 January 2020. Studies were included if they reported on at least six patients with biopsy-proven actinic cheilitis. After quality appraisal, results of studies with the strongest methodology criteria were synthesized. 18 studies of 411 patients (published 1985 to 2016) were included. The majority of the studies were case series. Carbon dioxide laser ablation and vermilionectomy were associated with the most favourable outcomes with fewest recurrences. Chemical peel and photodynamic therapy were associated with higher recurrence. Adverse effects generally resolved in the weeks following treatment and cosmetic outcomes were favourable overall. In conclusion, there is a lack of high-quality comparative studies evaluating different treatment options for actinic cheilitis. The included publications used various outcome measures; however, the majority reported on the recently defined core outcome sets. These results suggest that both carbon dioxide laser ablation and vermilionectomy are effective treatments for actinic cheilitis. Prospective head-to-head studies are needed to compare these treatment modalities and to assess patient preferences.

Sonidegib and vismodegib in the treatment of patients with locally advanced basal cell carcinoma: a joint expert opinion.

Sonidegib and vismodegib are hedgehog pathway inhibitors (HhIs) approved for the treatment of advanced basal cell carcinoma (BCC). Until recently, vismodegib was the only targeted treatment available for patients with locally advanced BCC (laBCC) in cases where surgery and radiotherapy are inappropriate. Sonidegib has recently been approved and now presents an alternative treatment option. The clinical differences between the two HhIs in patients with laBCC are unclear, as no head-to-head randomized controlled trials are or will be initiated. Moreover, there were important differences in the designs of their pivotal studies, BOLT (sonidegib) and ERIVANCE (vismodegib), and these differences complicate evidence-based analysis of their relative efficacy and safety profiles. In this paper, a group of clinical experts in the management of laBCC summarizes the clinical and pharmacological profiles of sonidegib and vismodegib based on published data and their own clinical experience. One key difference between the two pivotal studies was the criteria used to assess BCC severity. ERIVANCE (a single-arm phase II trial) used the conventional Response Evaluation Criteria in Solid Tumors (RECIST), while the more recent double-blind randomized BOLT trial used the stringent modified RECIST. A preplanned analysis adjusted the outcomes from BOLT with RECIST-like criteria, and this enabled the experts to discuss relative efficacy outcomes for the two treatments. Centrally reviewed objective response rate (ORR) for vismodegib was 47.6% (95% CI: 35.5-60.6) at 21-month follow-up using RECIST. After adjusting with RECIST-like criteria, the ORR for sonidegib according to central review at 18-month follow-up was 60.6% (95% CI: 47.8-72.4). Both treatments were associated with similar patterns of adverse events. Sonidegib and vismodegib share the same efficacy and tolerability profiles, but their pharmacokinetic profiles show several differences, such as volume of distribution and half-life. Further studies are needed to understand how these differences may impact clinical practice.

Stage IV cutaneous squamous cell carcinoma: treatment outcomes in a series of 42 patients.

BACKGROUND: The prevalence and incidence of cutaneous squamous cell carcinoma (cSCC) are increasing due to the ageing of the population and sun exposure. Advanced cSCC forms (locally advanced and/or locoregional metastatic and/or distant metastatic) account for approximately 3% of cSCC and can result in death. OBJECTIVE: Analysis of the clinical characteristics and treatment outcomes in stage IV cSCC with unresectable locoregional extension and/or the presence of metastases. METHODS: A retrospective study was conducted at a single-centre university hospital for stage IV cSCC patients followed between 1 January 2008 and 31 December 2015. Descriptive analyses (demographic, anatomo-clinical characteristics, treatment sequences, response to treatment and survival analysis) were performed. RESULTS: The study included 42 patients (median age = 75.5 years) with a diagnosis of stage IV cSCC who were treated with at least one line of chemotherapy and/or cetuximab. At the time of diagnosis, 85.7% of the patients had locoregional extension (19% of locally advanced and 67% of locoregional metastatic) and 14.3% had distant metastatic disease. Regarding treatment, 40% and 36% of patients received no more than 1 and 2 systemic treatment lines, respectively. The 4-year overall survival was 6%, and the median follow-up was 18.6 months. The objective response rate was 55% after the first line of treatment with a median progression-free survival (PFS) of 6.18 months and 12% after the second line with a median PFS of 6.51 months. Grade 3 and 4 adverse events were observed for 33% of patients. CONCLUSION: Our study confirms a very poor prognosis of stage IV cSCC and a poor response to conventional therapies, indicating that the stage IV cSCC patient population remains with unmet medical needs.

European Dermatology Forum guidelines on topical photodynamic therapy 2019 Part 2: emerging indications - field cancerization, photorejuvenation and inflammatory/infective dermatoses.

In addition to approved indications in non-melanoma skin cancer in immunocompetent patients, topical photodynamic therapy (PDT) has also been studied for its place in the treatment of, as well as its potential to prevent, superficial skin cancers in immune-suppressed patients, although sustained clearance rates are lower than for immune-competent individuals. PDT using a nanoemulsion of ALA in a daylight or conventional PDT protocol has been approved for use in field cancerization, although evidence of the potential of the treatment to prevent new SCC remained limited. High-quality evidence supports a strong recommendation for the use of topical PDT in photorejuvenation as well as for acne, refractory warts, cutaneous leishmaniasis and in onychomycosis, although these indications currently lack approvals for use and protocols remain to be optimized, with more comparative evidence with established therapies required to establish its place in practice. Adverse events across all indications for PDT can be minimized through the use of modified and low-irradiance regimens, with a low risk of contact allergy to photosensitizer prodrugs, and no other significant documented longer-term risks with no current evidence of cumulative toxicity or photocarcinogenic risk. The literature on the pharmacoeconomics for using PDT is also reviewed, although accurate comparisons are difficult to establish in different healthcare settings, comparing hospital/office-based therapies of PDT and surgery with topical ointments, requiring inclusion of number of visits, real-world efficacy as well as considering the value to be placed on cosmetic outcome and patient preference. This guideline, published over two parts, considers all current approved and emerging indications for the use of topical photodynamic therapy in Dermatology prepared by the PDT subgroup of the European Dermatology Forum guidelines committee. It presents consensual expert recommendations reflecting current published evidence.

European Dermatology Forum guidelines on topical photodynamic therapy 2019 Part 1: treatment delivery and established indications - actinic keratoses, Bowen's disease and basal cell carcinomas.

Topical photodynamic therapy (PDT) is a widely approved therapy for actinic keratoses, Bowen's disease (squamous cell carcinoma in situ), superficial and certain thin basal cell carcinomas. Recurrence rates when standard treatment protocols are used are typically equivalent to existing therapies, although inferior to surgery for nodular basal cell carcinoma. PDT can be used both as lesional and field therapies and has the potential to delay/reduce the development of new lesions. A protocol using daylight to treat actinic keratoses is widely practised, with conventional PDT using a red light after typically a 3-h period of occlusion employed for other superficial skin cancer indications as well as for actinic keratoses when daylight therapy is not feasible. PDT is a well-tolerated therapy although discomfort associated with conventional protocol may require pain-reduction measures. PDT using daylight is associated with no or minimal pain and preferred by patient. There is an emerging literature on enhancing conventional PDT protocols or combined PDT with another treatment to increase response rates. This guideline, published over two parts, considers all current approved and emerging indications for the use of topical PDT in dermatology, prepared by the PDT subgroup of the European Dermatology Forum guidelines committee. It presents consensual expert recommendations reflecting current published evidence.

Traitement médical des carcinomes basocellulaires avancés: Medical treatment of advanced basal cell carcinoma.

Until recently, advanced BCC were only accessible to a highly morbid surgery not necessarily proving to be carcinologic, and leaving terrible dysmorphic sequelae hard to accept by the patient. Another possibility, the only one in case of metastatic BCC, was chemotherapy which efficacy has never been proven in a clinical trial. Radiotherapy is most often not accessible because of previous radiotherapy or because of the localization or the extension of the lesion. The discovery of the importance of the sonic hedgehog pathway in the physiopathology of BCC has opened a new strategy with the development of targeted anti SMO drugs inactivating the pathway. Two molecules have become available following Phase I and II studies: vismodegib (Erivedge®) the first in class indicated for locally advanced and metastatic BCC and sonidegib (Odomzo®) indicated only for locally advanced BCC. The pharmacokinetic profiles of sonidegib and vismodegib showed several differences. No head to head comparative studies are available between these two drugs. Their pivotal phase II studies had similar study designs and endpoints. The objective response rate (ORR) by central review for vismodegib was 47.6% (95% CI 35.5-60.6) at 21 months follow-up. The ORR for sonidegib according to central review at 18 months follow-up is 56.1% (95% CI 43.3-68.3). Although both treatments share a similar adverse event profile with possible numerically differences in incidence, most patients will discontinue hedgehog inhibitors treatment in the long term because of side effects. Some resistant cases to these drugs have been described but are rather rare. In case of resistance or bad tolerability to the drug future hopes rely on immunotherapy currently under investigation. © 2018. Published by Elsevier Masson SAS. All rights reserved. Cet article fait partie du numéro supplément Prise en charge des carcinomes basocellulaires difficiles à traiter réalisé avec le soutien institutionnel de Sun Pharma.

Management of actinic keratosis at specific body sites in patients at high risk of carcinoma lesions: expert consensus from the AKTeam™ of expert clinicians.

Actinic keratoses (AK) arise on sun-exposed regions of the skin. If left untreated, AK may progress to invasive squamous cell carcinoma (SCC), although the rate of progression is low. A practical treatment algorithm for the treatment of AK in standard situations has been published by the AKTeam™ expert panel. However, management of particular situations of AK with increasing/higher carcinoma risk or AK progressing into carcinomas with increased aggressiveness due to their anatomical location (risky areas), or in patients with an increased risk of SCC requires further discussion. These include AK on the dorsal hands, forearms, legs, periorbital region, eyelids, ears, or lips, and organ transplant recipients, patients undergoing treatment with carcinogenic agents and patients with chronic lymphocytic leukaemia. The main objective was to propose therapeutic strategies for the treatment of AK located in risky areas and in patients with more invasive/aggressive lesions and a higher risk of progression to SCC. A systematic review of the literature was initially performed, and results were discussed by the experts to propose best management practices in specific situations. Finally, adapted management strategies for AK occurring in risky areas and in high-risk patients are presented, taking into account the experts' own clinical experience and current guidelines. In most of these 'at-risk' situations, patients can be treated according to the AKTeam™ treatment algorithm. Difficult-to-treat lesions should be treated more aggressively due to their higher risk of transformation. For patients with skin that is highly susceptible to actinic damage, monitoring and sun protection strategies are mandatory, and patients should undergo more regular follow-up. Further assessment of newer therapies in clinical trials is necessary to determine optimal treatment conditions. This expert consensus provides guidance for the management of AK in risky body sites and in patients with an increasing/higher risk for SCCs.

Vismodegib in patients with advanced basal cell carcinoma: Primary analysis of STEVIE, an international, open-label trial.

BACKGROUND: The SafeTy Events in VIsmodEgib study (STEVIE, ClinicalTrials.gov, NCT01367665), assessed safety and efficacy of vismodegib-a first-in-class Hedgehog pathway inhibitor demonstrating clinical benefit in advanced basal cell carcinoma (BCC)-in a patient population representative of clinical practice. Primary analysis data are presented. PATIENTS AND METHODS: Patients with locally advanced or metastatic BCC received oral vismodegib 150 mg/d until progressive disease, unacceptable toxicity, or withdrawal. Primary objective was safety. Efficacy variables were assessed as secondary end-points. RESULTS: Evaluable adult patients (N = 1215, 1119 locally advanced; 96 metastatic BCC) from 36 countries were treated; 147 patients (12%) remained on study at time of reporting. Median (range) treatment duration was 8.6 (0-44) months. Most patients (98%) had ≥1 treatment-emergent adverse event (TEAE). The incidence of the most common TEAEs was consistent with reports in previous analyses. No association between creatine phosphokinase (CPK) abnormalities and muscle spasm was observed. Serious TEAEs occurred in 289 patients (23.8%). Exposure ≥12 months did not lead to increased incidence or severity of new TEAEs. The majority of the most common TEAEs ongoing at time of treatment discontinuation resolved by 12 months afterwards, regardless of Gorlin syndrome status. Response rates (investigator-assessed) in patients with histologically confirmed measurable baseline disease were 68.5% (95% confidence interval (CI) 65.7-71.3) in patients with locally advanced BCC and 36.9% (95% CI 26.6-48.1) in patients with metastatic BCC. CONCLUSIONS: The primary analysis of STEVIE demonstrates that vismodegib is tolerable in typical patients in clinical practice; safety profile is consistent with that in previous reports. Long-term exposure was not associated with worsening severity/frequency of TEAEs. Investigator-assessed response rates showed high rate of tumour control. CLINICALTRIALS.GOV: NCT01367665.