Gaze cueing improves pattern recognition of histology learners.

Experts perceive and evaluate domain-specific visual information with high accuracy. In doing so, they exhibit eye movements referred to as "expert gaze" to rapidly focus on task-relevant areas. Using eye tracking, it is possible to record these implicit gaze patterns and present them to histology novice learners during training. This article presents a comprehensive evaluation of such expert gaze cueing on pattern recognition of medical students in histology. For this purpose, 53 students were randomized into two groups over eight histology sessions. The control group was presented with an instructional histology video featuring voice commentary. The gaze cueing group was presented the same video, but with an additional overlay of a live recording of the expert's eye movements. Afterward, students' pattern recognition was assessed through 20 image-based tasks (5 retention, 15 transfer) and their cognitive load with the Paas scale. Results showed that gaze cueing significantly outperformed the control group (p = 0.007; d = 0.40). This effect was evident for both, retention (p = 0.003) and transfer tasks (p = 0.046), and generalized across different histological contexts. The cognitive load was similar in both groups. In conclusion, gaze cueing helps histology novice learners to develop their pattern recognition skills, offering a promising method for histology education. Histology educators could benefit from this instructional strategy to provide new forms of attentional guidance to learners in visually complex learning environments.

Impact of an E-Learning Histology Course on the Satisfaction and Performance of Medical, Nursing and Midwifery Students / Impacto de un Curso E-Learning de Histología en la Satisfacción y Desempeño de Estudiantes de Medicina, Enfermería y Obstetricia

SUMMARY: The importance and relevance of e-learning courses in medicine and health sciences has increased significantly in the last decade. Despite this, there are few published teaching experiences of e-learning histology courses in the literature worldwide. The histology course we designed was structured on the Moodle platform as a learning management system, and the content was proposed in a synchronous (zoom) and asynchronous (recordings) format. We also included the use of free virtual microscopy tools. This study aimed to investigate the impact of an e-learning histology course on the satisfaction and performance of medical, nursing and midwifery students. The sample included 424 Chilean medical, nursing, and midwifery students from two cohorts. A Likert-type survey was administered at the end of the course. We performed exploratory analysis and ordinary least squares regression. In this study, we present a positive experience of an e-learning histology course. Exploratory factor analysis revealed three main factors related to "e- learning satisfaction", "in-person class activities", and "course design and teaching quality". We also found that there was a positive and significant relationship between students' perceptions of the adaptation of the traditional (face-to-face) histology course into an e-learning format and their academic performance. Our study shows that e-learning histology courses that integrate lectures and practical sessions can be a valuable teaching method for learning histology. Curriculum developers and teachers need to consider the limitations and advantages of this type of teaching and incorporate these three factors into the design and assessment of e-learning histology courses.

La importancia y relevancia de los cursos e-learning en medicina y ciencias de la salud ha aumentado significativamente en la última década. A pesar de ello, existen pocas experiencias docentes publicadas de cursos de histología e-learning en la literatura a nivel mundial. El curso de histología que diseñamos se estructuró en la plataforma Moodle, y los contenidos se propusieron en formato síncrono (zoom) y asíncrono (grabaciones). También incluimos el uso de herramientas gratuitas de microscopía virtual. Este estudio tuvo como objetivo investigar el impacto de un curso de histología e-learning en la satisfacción y el rendimiento de los estudiantes de medicina, enfermería y obstetricia. La muestra incluyó 424 estudiantes chilenos de medicina, enfermería y obstetricia de dos cohortes. Se aplicó una encuesta tipo Likert al final del curso. Se realizó un análisis exploratorio y una regresión por mínimos cuadrados ordinarios. En este estudio, presentamos una experiencia positiva de un curso de e-learning de histología. El análisis factorial exploratorio reveló tres factores principales relacionados con la "satisfacción sobre el aprendizaje e-learning", "clases presenciales versus clases virtuales" y el "diseño del curso y la calidad de la enseñanza". También encontramos que existía una relación positiva y significativa entre las percepciones de los estudiantes sobre la adaptación del curso de histología tradicional (presencial) a un formato e-learning y su rendimiento académico. Nuestro estudio muestra que los cursos de histología e-learning que integran clases teóricas y sesiones prácticas pueden ser una valiosa herramienta de enseñanza. Los responsables de la elaboración de planes de estudios y los profesores de histología deben tener en cuenta las limitaciones y ventajas de este tipo de enseñanza y sugerimos incorporar estos tres factores al diseño y la evaluación de los cursos de histología en línea.

Tumor de colision uterino: Reporte de un caso / Uterine collision tumor: Case report

La presencia de dos o más tipos de tumores en la misma zona del cuerpo es poco frecuente. El tumor compuesto o tumor de colisión presenta distintos subtipos histológicos en la misma región, con características clínicas, evolución y pronóstico diferente, diagnosticándose de forma incidental durante el estudio del otro. Se presenta un caso de una paciente quién fue diagnosticada con carcinoma epidermoide de cuello uterino estadio clínico IB1, tratada con cirugía (histerectomía radical Tipo III) que en el análisis histopatológico arroja dos subtipos histológicos, seguimiento con 4 años libres de enfermedad(AU)

The presence of two or more types of tumors in the same anatomic area is very strange. The compound tumor or coalition tumor presents different histological subtypes in the same region, with distinct clinical characteristics, evolution, and prognosis, being diagnosed incidentally during the study of the other. A case is presented of a patient who was diagnosed with squamous cell carcinoma of the cervix clinical stage IB1, treatedwith surgery (Type III radical hysterectomy) that in the histopathological analysis showed two histological subtypes, follow-up with 4 years free of disease(AU)

Bridging the gap in medical education: comparing analysis of light microscopy and virtual microscopy in histology.

This study aims to investigate the impact of virtual microscopy (VM) and light microscopy (LM) on the satisfaction of second-year medical students and how they affect student performance in different educational settings. The research involved 94 second-year students from Izmir Democracy University's School of Medicine, with criteria requiring enrollment in the 2021-2022 academic year and attendance of at least 80% in histology practical course. A paired two-tailed t-test was used for comparison, with a researcher-designed questionnaire for data collection. Cronbach's alpha was 0.894 for the LM questionnaire, and 0.918 for the VM questionnaire, indicating high level of reliability. LM scored higher in the questionnaire (p = 0.010), but VM showed higher exam averages (p = 0.013). The study found VM more effective in exams, with students showing high satisfaction with LM. VM's accessibility to histological preparations and its impact on learning levels and board exam success rates were noted. The study concludes that while VM is becoming essential in histology education due to its positive impact on exam performance and accessibility, LM remains highly valued by students for its hands-on experience and satisfaction levels.

Early practice makes histology masters: The use of a formative assessment quiz to prepare histology learners for a high-stakes final examination.

Assessment of learners in the anatomical sciences is a complex task as it not only tests students' fact knowledge, but also the analysis of visual information. Sometimes, novice histology learners must acquire image recognition skills of microscopic structures in a short time frame. This paper describes a strategy of offering first year dental students at the University of Michigan a short, non-grade contributing, formative assessment quiz in order to better prepare them for a high-stakes, final summative histology examination. Data collected over 7 years indicate that students, who made use of this formative assessment opportunity, performed significantly better in their summative examination than students, who did not. Especially early practice quiz users profited most. Students, who used the practice quiz until they achieved a perfect score, also had statistically higher final examination scores. Students, who did not use the practice quiz, had a significantly lower cumulative D1-year Grade Point Average (D1-GPA) than students, who did, indicating that academically weaker students often underuse supporting learning resources. In general, scores from the Dental Admission Test (DAT) were weak predictors of learning success in the DENT 510 histology course. In contrast, the D1-GPA values had a medium strength positive correlation with final histology examination scores. The major problem that was encountered with this practice quiz strategy was that many students waited until close to the day of the final examination before taking advantage of this feedback opportunity, thereby reducing its potential benefit for improving their overall learning strategy for histology.

Digital morphology network for effective teaching of cytology, histology and histopathology for medical and biology curriculum. VM3.0 Erasmus+ project.

INTRODUCTION: Digital microscopy transformation, the basis for the virtual microscopy applications, is a challenge but also a requirement in modern Medical Education. This paper presents the scope, background, methods, and results of the project "Digital Transformation of Histology and Histopathology by Virtual Microscopy (VM) for an Innovative Medical School Curriculum", VM3.0, funded by the European Union under the Erasmus+ framework (ref.no.2022-1- RO01-KA220-HED-000089017). The project was initiated at Grigore T. Popa University of Medicine and Pharmacy, Iași, Romania, with the support of Euroed Foundation, Iași, and cooperation of University partners from Gdansk (Poland), Plovdiv (Bulgaria), Alicante (Spain), and Patras (Greece) aimed to implement digital histology and histopathology teaching in a common network. MATERIALS AND METHODS: The backbone of the project was the development of a Digital Slide Platform based on the scans of histological slides collected from all the partners of the participating universities and the creation of a simple and fast digital/internet communication tool that could be used to improve histology and histopathology teaching of medical and natural sciences students. The construction of a Virtual Microscopy Library (VML) has been based on the acquisition of whole scans of high-quality histological slides stained by hematoxylin and eosin (H&E) and other classical staining methods and description of various organs' details in English as well as respective languages of the project's partners. The VML can be used for different approches, both for students' instruction in classes as well as for individual students' work and self-testing. Universities from other countries could use the modal structure of the developed VML system on the condition that more slides are provided and the implementation of national language(s) is implemented. CONCLUSIONS: The combined efforts of all university partners allowed to establish the dynamic low-cost virtual microscopy educational system. The VM system could help unify the standards of cytology, histology, and histopathology teaching in a quest for the digital transformation of the European educational system.

The Impact of Various Factors on the Difficulties in Learning and Teaching Strategies for Histology / El Impacto de Diversos Factores en las Dificultades en el Aprendizaje y las Estrategias de Enseñanza de Histología

SUMMARY: Histology is considered one of the most important but challenging topics in health sciences. Deficiencies in teaching and general histology directly affect the student's understanding, performance and promote dynamism and integration while covering the primary curriculum. The goal of the current study was to assess and provide a better experience of difficulties in learning histology, examine some standard teaching strategies, and determine how to implement suitable changes to improve the curriculum from students' perspectives. The study comprised of a self-administered questionnaire that included descriptive questions. Data was collected based on the survey conducted via 100 students studying histology. Data was analyzed further qualitatively and quantitatively to elaborate on the difficulties in this area. Many of them strongly agreed that the lack of essential comprehension regarding using light and electron microscopes resulted in challenges with comprehending and identifying tissue samples for image identification due to inadequate anatomical knowledge. Moreover, according to students, some difficulties understood the topic, perception of new terminologies, and insufficient teaching strategies to grasp students' interests. They also agreed that improvement was needed in terms of the modes of teaching employed by histology teachers; they felt that modern education techniques based on practical tasks should be incorporated to stimulate student interest and make understanding histological concepts easier. The Institution should modify the teaching system to allocate more time to relevant subjects to make this subject matter more interesting. This survey-based study evaluated that students faced some challenges while studying the current curriculum of histology. From the student's perspective, it is identified that some changes are needed to improve the course curriculum and way of teaching to make it more understandable.

La histología se considera uno de los temas más importantes pero desafiantes de las ciencias de la salud. Las deficiencias en la enseñanza y en la histología general afectan directamente la comprensión, el desempeño del estudiante y promueven el dinamismo y la integración al abarcar el currículo primario. El objetivo del estudio actual fue evaluar y proporcionar una mejor experiencia de las dificultades en el aprendizaje de histología, examinar algunas estrategias de enseñanza estándar y determinar cómo implementar cambios adecuados para mejorar el plan de estudios desde la perspectiva de los estudiantes. El estudio constaba de un cuestionario auto administrado que incluía preguntas descriptivas. Los datos se recopilaron a partir de una encuesta realizada a 100 estudiantes de histología. Los datos se analizaron más a fondo de forma cualitativa y cuantitativa para profundizar en las dificultades en esta área. Muchos de ellos estuvieron totalmente de acuerdo en que la falta de comprensión esencial sobre el uso de microscopios ópticos y electrónicos resultó en desafíos para comprender e identificar muestras de tejido para la identificación de imágenes debido a un conocimiento anatómico inadecuado. Además, según los estudiantes, algunas dificultades en la comprensión del tema, percepción de nuevas terminologías y estrategias de enseñanza insuficientes para captar los intereses de los estudiantes. También coincidieron en que era necesario mejorar los métodos de enseñanza empleados por los profesores de histología; sintieron que deberían incorporarse técnicas educativas modernas basadas en tareas prácticas para estimular el interés de los estudiantes y facilitar la comprensión de los conceptos histológicos. La Institución debería modificar el sistema de enseñanza para asignar más tiempo a materias relevantes para hacer esta materia más interesante. Este estudio basado en encuestas evaluó que los estudiantes enfrentaron algunos desafíos mientras estudiaban el plan de estudios actual de histología. Desde la perspectiva del estudiante, se identifica que se necesitan algunos cambios para mejorar el plan de estudios del curso y la forma de enseñar para hacerlo más comprensible.

Escape Room como Herramienta Didáctica en la Enseñanza de la Histología / Escape Room as a Didactic Tool in Histology Teaching

En el marco de un proceso de aprendizaje activo, se investigó el rendimiento académico a corto y a largo plazo de los estudiantes en dos sesiones prácticas de la asignatura de Histología a las que se incorporó un escape room. También se evaluó su impacto en la motivación y la retención del conocimiento. Los estudiantes fueron clasificados en un grupo control, que siguió una metodología de enseñanza tradicional, y un grupo experimental, que participó en la actividad del escape room. Los resultados revelaron mejoras significativas en las calificaciones posteriores a la intervención en el grupo experimental. El estudio también evaluó la percepción estudiantil de la experiencia del escape room que demostró valoraciones muy satisfactorias.

SUMMARY: In the context of an active learning process, this study investigated the short-term and long-term academic performance of students in two practical sessions of the Histology course, which included an escape room activity. The impact of this approach on motivation and knowledge retention was also assessed. Students were divided into a control group, which followed a traditional teaching methodology, and an experimental group, which participated in the escape room activity. The results revealed significant improvements in post-intervention grades in the experimental group. Additionally, the study assessed students' perceptions of the escape room experience, which showed highly satisfactory evaluations.

The impact of the integration of digital platforms and active teaching strategies (Kahoot!) on the performance of Brazilian medical course students in the discipline of histology.

Teaching human histology is part of understanding the tissues of the human body and, therefore, it is part of the training curriculum of all health courses. The increase in technologies and active teaching methodologies has a positive impact on student learning, as it reduces the challenges present in the subject. Therefore, this work aimed to compare the performance of students in the histology discipline, when compared to traditional teaching methodology and its association with game-based learning and a basic histology teaching platform. Three classes of the medical course were selected between the years 2022 and 2023, each of which was separated into a group. One group did not have access to any platform, being called the Traditional Group (TG), a group that used Kahoot!, being called the Kahoot Group (KG), and a group that used the teaching platform, being called the Histoatlas Group (HG). Both KG and HG groups showed greater effectiveness in learning and improved performance, when compared to TG. These improvements in KG and HG were also highlighted as learning aids and easy to use. KG students performed better in the practical test when comparing groups. However, this difference was not observed in the students' averages. However, students pointed out the relevance of trying to improve the traditional teaching methodology. Therefore, this study points out that, even though the traditional teaching methodology is efficient in the student's teaching and learning process, there is a need on the part of students to make the subject more dynamic.

Transforming histology students from passive lecture listeners into active lecture learners.

Traditional academic lectures have long been criticized as providing a passive learning environment to students. Often, they do not capture the audience's attention, resulting in learners being distracted or bored and thereby reducing their learning efficacy. Consequently, they are being abandoned by many schools and universities as an educational modus or modified into more learner-centered experiences. This descriptive article outlines a strategy of inserting active learning PowerPoint slides into traditional histology lectures. Suggestions and advice for adding or improving existing active learning slides are being offered to readers, who are planning to modify their own lecture presentations. The author's experience of using this formative assessment strategy with different types of histology learners is also discussed.

The increasing inclusion of technologies in histology teaching: A systematic review.

Histology is part of the curricular base of all health courses, being the basis for understanding the composition of all tissues in the human body. Over the years, more and more technologies have entered the academic environment, with the aim of improving the teaching and learning process. Thus, the objective of this work was to conduct a systematic review on the use of digital technologies in teaching histology. The PICo strategy was used to develop the guiding question and the results were presented in a Prisma Flow. The following platforms were used to search for articles: PubMed, Embase. Web of Science, Science Direct, Medline, Scielo, Periódicos CAPES and LILACS, Open Gray and Google Scholar, with a time limit between 2012 and 2022. The results showed that this area is still little explored, with there not being a wide range of technologies being used and applied in teaching, with gamification and virtual microscopy being the most applied. However, it was realized that the use of these technologies can improve student performance and increase their interest in the subject. Therefore, these tools are great methods to reduce difficulties and encourage the development of a more receptive environment for the histology teaching and learning process.

Registered multi-device/staining histology image dataset for domain-agnostic machine learning models.

Variations in color and texture of histopathology images are caused by differences in staining conditions and imaging devices between hospitals. These biases decrease the robustness of machine learning models exposed to out-of-domain data. To address this issue, we introduce a comprehensive histopathology image dataset named PathoLogy Images of Scanners and Mobile phones (PLISM). The dataset consisted of 46 human tissue types stained using 13 hematoxylin and eosin conditions and captured using 13 imaging devices. Precisely aligned image patches from different domains allowed for an accurate evaluation of color and texture properties in each domain. Variation in PLISM was assessed and found to be significantly diverse across various domains, particularly between whole-slide images and smartphones. Furthermore, we assessed the improvement in domain shift using a convolutional neural network pre-trained on PLISM. PLISM is a valuable resource that facilitates the precise evaluation of domain shifts in digital pathology and makes significant contributions towards the development of robust machine learning models that can effectively address challenges of domain shift in histological image analysis.

A pilot study on gamified and conventional e-quizzes reinforcing human histology among first-year medical and physiotherapy students.

The present retrospective, descriptive, and quasi-experimental study aimed to explore students' perceptions of traditional teaching combined with gamified and nongamified e-tests for postlecture reinforcement. Midterm knowledge retention and academic performance were also analyzed. The study was conducted from February 2021 to May 2022, involving a single group of first-year medical and physiotherapy students enrolled in equivalent core subjects on human histology at the University of Las Palmas de Gran Canaria (ULPGC). Lectures were supplemented with gamified Quizizz (QQ) or nongamified Moodle questionnaires (MQ) after lecture (t0) and 30 days later (t30). From 171 attendees, 162 volunteers were surveyed on their perceptions on the experience. Furthermore, 97 volunteers participated in the DOCENTIA-ULPGC survey on the students' satisfaction, and 123 participants individually answered 20 QQ and 20 MQ. Data were analyzed using the program Jamovi 2.3.24. The survey on volunteers' perception comprised 11 Likert items and 3 numerical scale items. The former showed acceptable internal consistency (ω-McDonald, 0.70) and validity (KMO, 0.58). Both types of e-questionnaires facilitated learning and motivated pre-reading contents but QQs were preferred. Reinforced lectures were rated higher than those unreinforced. Volunteers expressed higher overall satisfaction though DOCENTIA-ULPGC survey than the prepandemic control group. Average scores peaked at t0 with higher MQ rates. At t30, MQ and QQ scores were acceptable and similar. Participants' outcomes in the final exam tended to improve compared to the prepandemic control group, but without statistical significance. In summary, gamified and nongamified e-quizzes enhanced the student satisfaction and motivation and facilitated midterm knowledge retention.

Comparing the performance of artificial intelligence learning models to medical students in solving histology and embryology multiple choice questions.

INTRODUCTION: The appearance of artificial intelligence language models (AI LMs) in the form of chatbots has gained a lot of popularity worldwide, potentially interfering with different aspects of education, including medical education as well. The present study aims to assess the accuracy and consistency of different AI LMs regarding the histology and embryology knowledge obtained during the 1st year of medical studies. METHODS: Five different chatbots (ChatGPT, Bing AI, Bard AI, Perplexity AI, and ChatSonic) were given two sets of multiple-choice questions (MCQs). AI LMs test results were compared to the same test results obtained from 1st year medical students. Chatbots were instructed to use revised Bloom's taxonomy when classifying questions depending on hierarchical cognitive domains. Simultaneously, two histology teachers independently rated the questions applying the same criteria, followed by the comparison between chatbots' and teachers' question classification. The consistency of chatbots' answers was explored by giving the chatbots the same tests two months apart. RESULTS: AI LMs successfully and correctly solved MCQs regarding histology and embryology material. All five chatbots showed better results than the 1st year medical students on both histology and embryology tests. Chatbots showed poor results when asked to classify the questions according to revised Bloom's cognitive taxonomy compared to teachers. There was an inverse correlation between the difficulty of questions and their correct classification by the chatbots. Retesting the chatbots after two months showed a lack of consistency concerning both MCQs answers and question classification according to revised Bloom's taxonomy learning stage. CONCLUSION: Despite the ability of certain chatbots to provide correct answers to the majority of diverse and heterogeneous questions, a lack of consistency in answers over time warrants their careful use as a medical education tool.

Neuron parvum fluorescens, un Término con Influencia Anglo-Greco-Latina. Propuesta a Terminologia Neuroanatomica y Terminologia Histologica / Neuron Parvum Fluorescens, a Term with Anglo-Greco-Latin Influence. A Proposal to Terminologia Neuroanatomica and Terminologia Histologica

Las terminologías son utilizadas como instrumento lingüístico que permite la transmisión de conocimiento de manera precisa y sin ambigüedades en el ámbito de las ciencias. Los lineamientos de la Federative International Programme for Anatomical Terminology (FIPAT) refieren que la denominación de nombres estructurales debe ser descriptivos e informativos. Este estudio analiza las raíces lingüísticas que componen el término Neuron parvum valde fluorescens vigente en Terminologia Histologica y el término Neuron parvum fluorescens vigente en Terminologia Neuroanatomica. Las células pequeñas intensamente fluorescentes son neuronas que se encuentran en el sistema nervioso autónomo, distribuidas en los ganglios simpáticos. Estas células presentan sinapsis aferentes con terminales nerviosas simpáticas preganglionares y sinapsis eferentes con las dendritas de las neuronas posganglionares. Su función es regular la transmisión ganglionar, actuando como interneuronas con señalización paracrina y endocrina. Además, se caracterizan por ser células fluorescentes, que expresan catecolaminas; serotonina, noradrenalina y dopamina. Se realizó una búsqueda en Terminologia Histologica y Terminologia Neuroanatomica, con una traducción de los términos al español. Además, la búsqueda se complementó en un diccionario etimológico en inglés para los términos correspondientes. Esta investigación encontró diferencia entre la traducción del latín al español del término fluorescens, quien posee un origen etimológico muy diferente a su significado en español. El término Neuron parvum valde fluorescens en Terminologia Histologica y el término Neuron parvum fluorescens en Terminologia Neuroanatomica, identifican a la misma estructura. Se sugiere reemplazar ambos términos por Cateconeuron ganglionare, entregando así una correcta descripción de este tipo de neurona, considerando su ubicación y función. Además, de esta manera ser un término concordante en latín para su incorporación en Terminologia Neuroanatomica y Terminologia Histologica.

SUMMARY: Terminologies are used as a linguistic tool to convey knowledge in a precise and unambiguous manner in science. The guidelines of the Federative International Programme for Anatomical Terminology (FIPAT) state that the names given to structures should be both descriptive and informative. This study analyses the linguistic roots of the term Neuron parvum valde fluorescens in Terminologia Histologica and the term Neuron parvum fluorescens in Terminologia Neuroanatomica. Small intensely fluorescent cells are neurons found in the autonomic nervous system, distributed in the sympathetic ganglia, they have afferent synapses with preganglionic sympathetic nerve terminals and efferent synapses with the dendrites of postganglionic neurons, whose function is to regulate ganglionic transmission, acting as interneurons with paracrine and endocrine signalling. They are also characterized as fluorescent cells, producing the catecholamines: serotonin, noradrenaline and dopamine. A search was carried out in Terminologia Histologica and Terminologia Neuroanatomica, with a translation of the terms into Spanish. This was complemented by a search in an English etymological dictionary for the corresponding terms. This research found a difference between the Latin to English translation of the term fluorescens, which has a very different etymological origin to its English meaning. The term Neuron parvum valde fluorescens in Terminologia Histologica and the term Neuron parvum fluorescens in Terminologia Neuroanatomica identify the same structure. The proposal is to replace both terms with Cateconeuron ganglionare, thus affording an accurate description of this type of neuron, considering its location and function. Moreover, it would also be a concordant term in Latin for its incorporation into the Terminologia Neuroanatomica and Terminologia Histologica.

Caracterización histológica del melanoma cutáneo en reportes de patología en la ciudad de Cali, 2016-2021 / Histological characterization of cutaneous melanoma in pathology reports in the city of Cali, 2016-2021

Introducción. El melanoma es la proliferación maligna de melanocitos asociado a un comportamiento agresivo. El objetivo de este estudio fue determinar las variables histológicas del melanoma cutáneo. Métodos. Estudio observacional retrospectivo, transversal descriptivo, realizado con reportes de patologías de pacientes con diagnóstico de melanoma cutáneo en un laboratorio de patología en Cali, Colombia, entre 2016-2021. Se incluyeron las variables edad, sexo, localización, subtipo, espesor de Breslow, ulceración, márgenes, mitosis, invasión linfovascular, neurotrofismo, regresión tumoral, nivel de Clark e infiltración tumoral por linfocitos. Resultados. Se obtuvieron 106 reportes y fueron excluidos 54 por duplicación. Se incluyeron 52 registros, la media de edad fue de 61 años, con una mayor frecuencia de mujeres (55,8 %). De los 33 casos donde se especificó el subtipo histológico, el más frecuente fue el de extensión superficial (66,6 %), seguido del acral lentiginoso (18,1 %) y nodular con (15,2 %). La localización más frecuente fue en extremidades (61,5 %). El espesor de Breslow más común fue IV (34,6 %) y el nivel de Clark más frecuente fue IV (34,6 %). La ulceración estuvo en el 40,4 %. El subtipo nodular fue el de presentación más agresiva, donde el 100 % presentaron espesor de Breslow IV. Conclusiones. El subtipo de melanoma más común en nuestra población fue el de extensión superficial; el segundo en frecuencia fue el subtipo acral lentiginoso, que se localizó siempre en extremidades. Más del 50 % de los melanomas tenían espesor de Breslow mayor o igual a III, lo que impacta en el pronóstico.

Background. Melanoma is the malignant proliferation of melanocytes associated with aggressive behavior. The objective of this study was to determine the histological variables of cutaneous melanoma. Methods. Observational, cross-sectional, descriptive, retrospective study carried out with reports of pathologies with a diagnosis of cutaneous melanoma in a pathology laboratory in Cali between 2016-2021. The variables were age, sex, location, subtype, Breslow thickness, ulceration, margins, mitosis, lymphovascular invasion, neurotropism, tumoral regression, Clark level and tumor infiltration by lymphocytes. Results. One hundred and six reports were obtained and 54 were excluded due to duplication. A descriptive analysis was made on the 52 records that were included, the mean age was 61 years, with a higher frequency in women with 55.8%. Of the 33 cases where the histological subtype was specified, the most frequent was superficial extension with 66.6%, followed by acral lentiginous with 18.1% and nodular with 15.2%. The most frequent location was in the extremities (61.5%); the most common Breslow was IV (34.6%), and the most frequent Clark was IV (34.6%). Ulceration was in 40.4%. The nodular subtype was the most aggressive presentation where 100% presented Breslow IV. Conclusions. The most common subtype of melanoma was that of superficial extension. In our population, the second most frequent was the acral lentiginous subtype, which was always located on the extremities. More than 50% of the melanomas had Breslow greater than or equal to III, which affects the prognosis.

Histomorphometric comparison of two different preclinical models to evaluate the bone repair in grafted areas

Aim: This study was performed to compare two different rat defect models (critical calvaria defects versus guided bone regeneration in the mandibular ramus) used to evaluate bone repair in grafted areas. Methods: A total of 12 rats were allocated in two groups according the experimental model used to evaluate the bone repair in grafted areas: a critical sized-calvaria defect of 5 mm filled with bone graft (n=6) and a mandibular ramus filled with the bone graft associated with a Teflon dome-shaped membrane (n=6). Both groups were grafted with deproteinized bovine bone graft. After 60 days, the animals were euthanized and the samples obtained were submitted to histomorphometry analysis to evaluate the relative amount of bone, remaining bone substitute, and soft tissue within the grafted areas. Results: No differences were observed between the preclinical models evaluated in relation to the amount of bone tissue formation (19.93 ± 4.55% in calvaria vs. 21.00 ± 8.20% in mandible). However, there was a smaller amount of soft tissue (43.20 ± 10.97% vs. 57.79 ± 7.61 %; p<0.01) and a greater amount of bone substitute remaining (35.80 ± 5.52% vs. 22.28 ± 4.36 %; p<0.05) in the grafted areas in the mandible compared to calvaria defect. Conclusion: Preclinical models for the analysis of bone repair in grafted areas in the mandible and critical sized-calvaria defects showed different responses in relation to the amount of soft tissue and bone substitute remnants