Browsing by Author "Uribe, Pablo"

Now showing 1 - 11 of 11
  • Thumbnail Image
    Item
    A systematic review and meta-analysis of artificial intelligence versus clinicians for skin cancer diagnosis
    (2024) Salinas, María Paz; Sepúlveda, Javiera; Hidalgo, Leonel; Peirano, Dominga; Morel, Macarena; Uribe, Pablo; Rotemberg, Verónica; Briones, Juan; Mery, Domingo; Navarrete-Dechent, Cristian
    Scientific research of artificial intelligence (AI) in dermatology has increased exponentially. The objective of this study was to perform a systematic review and meta-analysis to evaluate the performance of AI algorithms for skin cancer classification in comparison to clinicians with different levels of expertise. Based on PRISMA guidelines, 3 electronic databases (PubMed, Embase, and Cochrane Library) were screened for relevant articles up to August 2022. The quality of the studies was assessed using QUADAS-2. A meta-analysis of sensitivity and specificity was performed for the accuracy of AI and clinicians. Fifty-three studies were included in the systematic review, and 19 met the inclusion criteria for the meta-analysis. Considering all studies and all subgroups of clinicians, we found a sensitivity (Sn) and specificity (Sp) of 87.0% and 77.1% for AI algorithms, respectively, and a Sn of 79.78% and Sp of 73.6% for all clinicians (overall); differences were statistically significant for both Sn and Sp. The difference between AI performance (Sn 92.5%, Sp 66.5%) vs. generalists (Sn 64.6%, Sp 72.8%), was greater, when compared with expert clinicians. Performance between AI algorithms (Sn 86.3%, Sp 78.4%) vs expert dermatologists (Sn 84.2%, Sp 74.4%) was clinically comparable. Limitations of AI algorithms in clinical practice should be considered, and future studies should focus on real-world settings, and towards AI-assistance.
  • No Thumbnail Available
    Item
    Accuracy in anatomical location on dermatological surgery: a multi‐centre retrospective study
    (2023) Donoso, Francisca; Hidalgo, Leonel; Cowen, Emily A.; Villagran, Sofía; Villablanca, Paula; Puerto, Constanza del; Silva‐Valenzuela, Sergio; Galimany, Lucas; Majerson, Daniela; Andino, Romina; Uribe, Pablo; Droppelmann, Katherine; Cárdenas, Consuelo; Abarzúa‐Araya, Álvaro; Castro‐Ayala, Juan C.; Kurtansky, Nicholas R.; Halpern, Allan C.; Molenda, Matthew A.; Rotemberg, Veronica; Navarrete-Dechent, Cristian
  • Thumbnail Image
    Item
    Allelotyping, Microsatellite Instability, and BRAF Mutation Analyses in Common and Atypical Melanocytic Nevi and Primary Cutaneous Melanomas
    (LIPPINCOTT WILLIAMS & WILKINS, 2009) Uribe, Pablo; Wistuba, Ignacio I.; Gonzalez, Sergio
    Loss of heterozygosity (LOH) in several chromosomal regions is found in melanoma, and it has been partially studied in nevi. BRAF mutations are found in melanoma and nevi and in colorectal cancer are linked to mismatch repair deficiency. We studied early genetic events involved in melanomagenesis through analysis of allelic loss, microsatellite instability (MSI), and BRAF mutations.
  • Thumbnail Image
    Item
    Author Correction: A systematic review and meta-analysis of artificial intelligence versus clinicians for skin cancer diagnosis
    (2024) Salinas Espinoza, María Paz; Sepúlveda, Javiera; Hidalgo, Leonel; Peirano, Dominga; Morel, Macarena; Uribe, Pablo; Rotemberg, Verónica; Briones, Juan; Mery, Domingo; Navarrete Dechent, Cristian Patricio
  • Thumbnail Image
    Item
    Clinical and dermoscopic evaluation of melanocytic nevi changesduring diode laser hair removal: A prospective study
    (2022) Acle, Renata; Zambrano‐Mericq, María José; Navarrete‐Dechent, Cristián; Uribe, Pablo; Abarzúa‐Araya, Álvaro
    Abstract Background: Laser hair removal (LHR) is a common practice with increasing useworldwide. Clinical and dermoscopic changes in melanocytic nevi after LHR havebeen reported but prospective studies are lacking. Objective: To describe dermoscopic changes of melanocytic nevi at different timepoints after LHR. Methods: Prospective study in a cohort of female patients undergoing diode LHR. Dermoscopic follow‐up of at least three nevi on the legs that underwent hairremoval. We included three nonexposed nevi on the arms as controls. Twoblinded investigators analyzed dermoscopic images, according to variablesselected based on the available literature. Results: Thirty‐four patients were included with a total of 148 nevi on the legs and112 nevi on the arms (controls). 47.9% (71/148) of the nevi on the legs had evidenceof dermoscopic changes at the sixth hair removal session, compared to 9.8% (11/112)on controls (p< 0.001). The most frequent change was“bleaching”(41.9%, 62/148).Also, we observed “irregular hyperpigmented areas,”and “regression structures” in5.4% (8/148) and 4.7% (7/148) of the cases at the sixth session, respectively. Neitherof these structures were observed in the controls (p<0.05). Limitations: Only females were included; we did not perform histopathologicalevaluation nor reflectance confocal microscopy of changing nevi. Conclusion: Melanocytic nevi frequently change after diode LHR. The changescannot always distinguish between LHR induced and melanoma, so we adviseavoiding nevi during laser therapies with melanin targets.
  • No Thumbnail Available
    Item
    Differential expression of programmed cell death ligand 1 (PD-L1) and inflammatory cells in basal cell carcinoma subtypes
    (2022) Gompertz-Mattar, Matias; Perales, Juan; Sahu, Aditi; Mondaca, Sebastian; Gonzalez, Sergio; Uribe, Pablo; Navarrete-Dechent, Cristian
    Few studies have evaluated programmed cell death ligand (PD-L1) expression and lymphocytic infiltrates in Basal Cell Carcinoma (BCC). The objectives of this study are to assess PD-L1 expression and markers of local immune response in nodular, superficial, and morpheaform BCC, and compare it to normal, sun-exposed skin from the periphery of intradermal nevi. This was a retrospective study that included three histological subtypes of BCCs, and sun-exposed skin from the periphery of dermal nevi as quality controls. Tissue microarrays (TMA) were constructed with subsequent staining of H&E and immunohistochemistry (IHC) for CD4, CD8, FOXP3 and PD-L1. Non-automated quantification of the infiltrate in the intratumoral and stromal compartments on TMAs was performed. A total of 115 BCC (39 nodular, 39 morpheaform, and 37 superficial) and 41 sun-exposed skin samples were included (mean age 65.4 years; 52.6% females). BCC showed higher expression of PD-L1 (5.4 vs 0.7%, p < 0.001), CD8 (29.8 vs 19.7%, p = 0.002), and FOXP3 (0.3 vs 0.06%, p = 0.022) compared to sun-exposed skin. There was a higher PD-L1 expression in nodular BCC compared with other subtypes. Low-risk BCC subtypes (superficial and nodular) exhibited more PD-L1 expression in intratumoral and stromal immune infiltrates as compared to high-risk BCC subtypes. As a limitation, no immune cells function was evaluated in this study, only the presence/absence of T-lymphocyte sub-populations was recorded. Substantial differences in both PD-L1 expression and lymphocytic infiltrates were found amongst the histological subtypes of BCC and sun-exposed skin. Highest PD-L1 expression was found in nodular BCCs which suggests a potentially targetable strategy in the treatment of this most common BCC subtype.
  • No Thumbnail Available
    Item
    Einfache Hamostase an der Kopfhaut bei dermatologischen Operationen durch Kochsalzlosung
    (2023) Hidalgo, Leonel; Carrasco, Karina; Navarrete-Dechent, Cristian; Chen, Curtis; Uribe, Pablo; Carreno, Nestor
  • Thumbnail Image
    Item
    Lack of association between BRAF mutation and MAPK ERK activation in melanocytic nevi
    (NATURE PUBLISHING GROUP, 2006) Uribe, Pablo; Andrade, Leonardo; Gonzalez, Sergio
    The mitogen-activated protein kinase (MAPK) extracellular signal-regulated kinase signaling pathway can be activated through mutations of V-RAF murine sarcoma viral oncogene homolog B1 (BRAF) oncogene, frequently found in melanoma (60%), common nevi (CN) (73-82%), and atypical nevi (AN) (52-80%). MAPK activation has been reported between 0 and 22% in nevi, and 86% of primary melanoma, without any knowledge of BRAF mutational status. We studied the correlation of MAPK activation status, BRAF mutation, and B-Raf expression in CN, AN, and melanoma. Using immunohistochemistry, phosphorylated (active) MAPK and B-Raf expression was studied in 24 CN, 21 AN, and 26 primary cutaneous melanomas (PM). BRAF mutations at codon 600 were assessed by PCR-RFLP. Active MAPK was detected in 29% of CN, 48% of AN, and 85% of PM. BRAF mutation was found in 67% of CN, 62% of AN, and 58% of PM. In all, 23% of CN, 54% of AN, and 93% of PM with BRAF mutation have activated MAPK. All lesions expressed B-Raf. BRAF mutation does not seem to be sufficient to produce MAPK activation in melanocytic nevi, and it is suggested that other events are needed to induce MAPK activation, that is, B-Raf overexpression, inhibition of MAPK phosphatases, or suppression of RAF kinase inhibitors.
  • Thumbnail Image
    Item
    Melanocytes and Keratinocytes Transfer Using Sandpaper Technique Combined with Dermabrasion for Stable Vitiligo
    (LIPPINCOTT WILLIAMS & WILKINS, 2011) Quezada, Natacha; Machado Filho, Carlos App; De La Sotta, Pilar; Uribe, Pablo
    BACKGROUND Surgery is currently the most successful approach for difficult cases of vitiligo. The efficacy of epidermal surface removal (dermabrasion) is near 50%, and the efficacy of grafts is 70%.
  • Thumbnail Image
    Item
    Multiple aggregated yellow‐white globules, a dermoscopic sign to be considered in the presurgical evaluation in Mohs surgery
    (2022) Hidalgo, Leonel; Donoso, Francisca; Guzmán, Mariana; Millán, Rocío; Curi, Maximiliano; Misad‐Saide, Carlos; Cárdenas, Consuelo; Droppelmann, Katherine; Abarzúa, Álvaro; Uribe, Pablo; Navarrete-Dechent, Cristian
  • No Thumbnail Available
    Item
    Understanding current therapies in metastatic melanoma
    (SOC MEDICA SANTIAGO, 2016) Rodriguez, Rocio; Para, Angela; Gonzalez, Sergio; Molgo, Montserrat; Droppelmann, Nicolas; Acevedo, Francisco; Pena, Jose; Uribe, Pablo
    Cutaneous melanoma is a highly aggressive tumor developing from melanocytes, its incidence is increasing, and prognosis in advanced stages is daunting. New therapies have been approved during the recent years with unprecedented results, including inhibitors of MAPK/ERK pathway and immune checkpoint blockade (anti-cytotoxic T lymphocyte antigen- 4 (CTLA-4) as ipilimumab, anti-programmed cell death protein 1 (PD-L1) as pembrolizumab and anti-programmed cell death protein 1 ligand (PD-L1), among many others). The aim of this paper is to review currently available metastatic melanoma therapies focusing mainly on new therapies that have demonstrated effectiveness, after several decades of little progress in the treatment of this disease.