Renato Marchiori Bakos’s research while affiliated with Hospital de Clínicas de Porto Alegre and other places

Whether dermatoscopy deep features could serve as biomarker for the prediction of melanoma metastasis, remains an underexplored area in medical research. In this cohort of 712 patients from ten centers from 3 different continents, a support vector machine (SVM) classifier, analyzing deep features from dermatoscopic images, demonstrated similar prognostic performance for metastasis, in terms of AUC and true positive rate, to current benchmarks of melanoma staging, namely Breslow thickness and ulceration. Deep features derived from dermatoscopy could predict, at the time of diagnosis, early-stage melanomas with high metastatic potential, tailoring further treatment strategies.

9565 Background: Machine learning algorithms, and especially convolutional neural networks, demonstrated modest accuracy on the prediction of melanoma metastasis, based on histological images and clinicopathological information. Whether dermatoscopy deep features could serve as biomarker for the prediction of melanoma metastasis, remains an underexplored area in medical research. Methods: An international, multicenter, cohort study of cutaneous melanoma patients from 3 different continents was conducted. Patients with cutaneous melanoma, who had available clinical and dermatoscopic images and an adequate follow-up time for the development of metastasis (both locoregional and distant) were included. We utilized a support vector machine (SVM) classifier, to distinguish between melanomas that metastasized and those that did not. We used a pre-trained ResNet 50 network, we separated dataset into training set and testing set, stratified by TNM-stage, and to ensure robustness and guard against biased data selection, the stratified split into training and testing sets was repeated five times, resulting in five different training-test sets. The primary outcome was the comparison of the prognostic performance of deep dermatoscopy features based on SVM (model 1) to the performance of established prognostic factors of melanoma, such as Breslow thickness and ulceration (model 2) and to a combined model using deep features and histopathologic factors (model 3). A secondary aim was to examine the diagnostic performance of model 1 in stage IIB and IIC patients at diagnosis. The prognostic performance was assessed using the Area Under the Curve (AUC) and the True Positive Rate (TPR) at a True Negative Rate at 70%. Results: 712 patients were included, 465 (65.3%) non-metastatic and 247 (34.7%) metastatic, within a median follow-up of 60 months. The SVM model demonstrated mean AUC 0.84 (95% CI 0.80 – 0.87) and TPR 0.81 (95%CI 0.73 – 0.90). Similar results were shown for model 2 and model 3, and no statistically significant differences among models were detected in terms of AUC (De Long’s test, p>0.05 and ANOVA Kruskal-Wallis p>0.05). Regarding IIB/IIC patients and combining data from five test sets, SVM correctly classified as metastatic 21 out of 23 (91.3%) stage IIB and 21 out of 23 (91.3%) stage IIC patients, who eventually developed metastasis during follow-up. Conclusions: Our findings suggest that dermatoscopy deep features could offer an immediate, in vivo prediction of melanoma metastasis prior to excision. This advancement holds significant clinical importance, prioritizing high-risk patients for neoadjuvant treatment or guiding selection of patients who might benefit from adjuvant therapy.

Introduction: Studies focused on dermoscopic aspects of pigmented Bowen disease (pBD) in Latin American population are scarce and limited to only case reports or small series. Objectives: To report dermoscopic findings in a large series of 147 pBD diagnosed in Ibero-Latin American population. Methods: We conducted a multicentric, retrospective study on 147 histologically proven pBD under the auspices of the Dermoscopy Chapter of the Ibero-Latin American College of Dermatology. Results: The study population consisted of 77 females (52%) and 70 males (48%) with a mean age of 68.6 years. 70.1% of patients had skin phototype 3, 15.6% to skin phototype 2, and 14.3% to skin phototype 4. On clinical examination, near 60% of pBD were flat, 70% presented with scales, and 90% were asymmetric. Under dermoscopy, structureless hypopigmented areas, dots brown and pink color were the most frequently observed. Regarding specific dermoscopic clues to pBD, the most prevalent were structureless hypopigmented areas, vessels arranged in linear fashion at the periphery, and pigmented lines or pigmented dots distributed in a linear fashion. Clustered, coiled, and dotted vessels were observed in 55.8%, 45.6%, and 45.6% of the cases, respectively. Conclusions: We report a large series of cases of pBD in Latin American patients, with most patients being skin phototype 3 and 4. Distinctively in our study, the pigmented structures and the clues derived from the presence of melanin were much more frequent than in previous reports in fair skin.

Background The detection of cutaneous metastases (CMs) from various primary tumours represents a diagnostic challenge. Objectives Our aim was to evaluate the general characteristics and dermatoscopic features of CMs from different primary tumours. Methods Retrospective, multicentre, descriptive, cross‐sectional study of biopsy‐proven CMs. Results We included 583 patients (247 females, median age: 64 years, 25%–75% percentiles: 54–74 years) with 632 CMs, of which 52.2% ( n = 330) were local, and 26.7% ( n = 169) were distant. The most common primary tumours were melanomas ( n = 474) and breast cancer ( n = 59). Most non‐melanoma CMs were non‐pigmented ( n = 151, 95.6%). Of 169 distant metastases, 54 (32.0%) appeared on the head and neck region. On dermatoscopy, pigmented melanoma metastases were frequently structureless blue (63.6%, n = 201), while amelanotic metastases were typified by linear serpentine vessels and a white structureless pattern. No significant difference was found between amelanotic melanoma metastases and CMs of other primary tumours. Conclusions The head and neck area is a common site for distant CMs. Our study confirms that most pigmented melanoma metastasis are structureless blue on dermatoscopy and may mimic blue nevi. Amelanotic metastases are typified by linear serpentine vessels and a white structureless pattern, regardless of the primary tumour.

Background: The factors necessitating the need for referrals for in-person evaluations by a dermatologist are not adequately understood and have not been studied using automated text mining so far. The objective of this study was to compare the prevalence of required in-person dermatologist care in the presence or absence of certain clinical features. Methods: Observational cross-sectional study of 11,661 teledermatology reports made from February 2017 to March 2020. Results: The need for dermoscopy was associated with a 348% increase in the possibility of referral for in-person dermatologist evaluations (prevalence ratio [PR]: 4.48, 95% confidence interval [CI]: 4.17-4.82). Infectious diseases were associated with a 64% lower possibility of referral (PR: 0.36, 95% CI: 0.30-0.43). Discussion: Some lesions and poorly documented cases are challenging to assess remotely. This study presents a different approach to research more detailed data from teledermatology reports, using text mining, and points out the risk magnitude for demanding dermatologic in-person care of which feature analyzed. As limitations, the variables related to lesion location, size, and extension were not analyzed and the dictionaries used were originally in Brazilian Portuguese. Conclusions: Teledermatology seems sufficient for the management of 75% of clinical cases, especially acute in young patients with inflammatory or infectious lesions. Referrals for in-person dermatologist consultations were not only strongly associated with the need for dermoscopy, but also for therapeutic reasons like surgical procedures, phototherapy, and the use of some systemic medications.

Different nonpigmented skin lesion in head and neck area such as Lymphoma, Pseudo lymphoma, Basal cell carcinoma, Basosquamous carcinoma, Squamous cell carcinoma, Keratoacanthoma, Seborrheic Keratosis, Clear cell acanthoma and Fibrosing alopecia are described. Histopathological clinical considerations are made and its dermaroscopic characteristics are also described.KeywordsLymphomaPseudo lymphomaBasal cell carcinomaBasosquamous carcinomaSquamous cell carcinomaKeratoacanthomaSeborrheic KeratosisClear cell acanthomaFibrosing alopecia

Cutaneous squamous cell carcinoma (cSCC) is the second most common human cancer and is related to metastatic disease and death. Early recognition and appropriated treatment are paramount for the prevention of neoplastic progression. Actinic keratosis (AK) and field cancerization are precursors of cSCC. The therapeutic interventions in patients with AK, severe actinic damage, and low- and high-risk cSCC are reviewed in this chapter as well as new systemic treatments such as targeted therapy and immune-checkpoint inhibitors for locally advanced and metastatic cSCC.KeywordsNeoplasmsSquamous cell carcinomaActinic keratosisSkin neoplasmsBowen’s diseaseField cancerizationStagingTreatment

Introduction: Skin cancer remains a global public health burden. Dermoscopy is a useful technique that aids in early detection and increases diagnostic accuracy with adequate training. However, dermoscopy is not uniformly taught to residents worldwide. Dermoscopy training in Latin American dermatology residency programs has not been explored. Objectives: To assess current dermoscopy training among dermatology residency programs in Latin America (eg training modalities, preferred/most effective modalities per residents, diseases/pathologies taught). Methods: Cross-sectional survey distributed via e-mail between March and May 2021. Chief residents from Argentina, Brazil, Colombia, Costa Rica, Chile, Ecuador, Guatemala, Mexico, Panama, and Uruguay were invited to participate. Results: 81 chief residents completed the questionnaire (81/126, 64.2%). Seventy-two percent of programs had an established dermoscopy curriculum, with dedicated hours of training varying greatly by program. Institutions commonly utilized sessions with "unknown" dermoscopy images and direct teaching by experts in the clinical setting as supplements to lectures, also described by residents as most effective. The most commonly taught methods included pattern analysis (74.1%), the two-step algorithm (61.7%), and the ABCD rule (59.3%). Almost all respondents reported desiring additional training during residency and believe that dermoscopy training should be a requirement to graduate from residency. Conclusions: This study highlights a preliminary look into current landscape in dermoscopy training among selected Latin American dermatology residency programs, demonstrating room for improvement and standardization in dermoscopic education and training. Our results serve as a baseline reference and provide valuable information to guide future educational initiatives incorporating successful teaching strategies (eg. spaced education/repetition, flipped classroom model) used in dermatology and other fields.

People participate in sports for recreational, social, and/or health purposes. Additionally, some may invest in sports as a professional career. Distinct aspects are important with regard to athletes’ health and dermatology. Athletes are particularly prone to develop distinct cutaneous reactions or diseases, most being infectious or traumatic. Patients with preexisting skin diseases may have worsening of the symptoms depending on sports activities. Preventive measures to avoid reactions to the environmental aspects such as weather, UV radiation, or pressure/friction from sports equipment are also significant for professional athletes’ cutaneous homeostasis and to improve performance. Moreover, some infectious diseases when active may eliminate athletes from official competitions. Finally, some prescriptions commonly used in dermatology may be included in the prohibited substance list of some sports. Therefore, it is extremely important for dermatologists to detect and treat the cutaneous reactions associated with sports participation and to be aware of the distinct aspects related to sports and dermatologic prescriptions.KeywordsSportsDermatologyDopingAthletesInfectious diseasesTraumatic diseasesHerpesSkin cancerPhotoprotectionBacterial infectionsUrticariaDermatitis

Introduction: In patients with multiple nevi, sequential imaging using total body skin photography (TBSP) coupled with digital dermoscopy (DD) documentation reduces unnecessary excisions and improves the early detection of melanoma. Correct patient selection is essential for optimizing the efficacy of this diagnostic approach. Objectives: The purpose of the study was to identify, via expert consensus, the best indications for TBSP and DD follow-up. Methods: This study was performed on behalf of the International Dermoscopy Society (IDS). We attained consensus by using an e-Delphi methodology. The panel of participants included international experts in dermoscopy. In each Delphi round, experts were asked to select from a list of indications for TBSP and DD. Results: Expert consensus was attained after 3 rounds of Delphi. Participants considered a total nevus count of 60 or more nevi or the presence of a CDKN2A mutation sufficient to refer the patient for digital monitoring. Patients with more than 40 nevi were only considered an indication in case of personal history of melanoma or red hair and/or a MC1R mutation or history of organ transplantation. Conclusions: Our recommendations support clinicians in choosing appropriate follow-up regimens for patients with multiple nevi and in applying the time-consuming procedure of sequential imaging more efficiently. Further studies and real-life data are needed to confirm the usefulness of this list of indications in clinical practice.