Lower limb cutaneous melanoma surgery: location matters.

The anatomical location of cutaneous melanoma is a relevant independent prognostic factor in melanoma. The aim of the study is to know the prognosis of lower limb cutaneous melanoma related to their location within the limb, regardless of the histological type, and if there are any other influencing variables. A real-world data observational study was developed. The lesions were divided depending on the location of the melanoma (thigh, leg and foot). Bivariate and multivariate analysis were performed, and melanoma-specific survival and disease-free survival rates were calculated. When these analysis were done, the results showed that, in melanomas of the lower limb, location on the foot presented a lower melanoma-specific survival rate compared to more proximal locations, and only the anatomical location presents statistical significance to discriminate cases with a higher mortality risk and a lower disease-free survival rate among distal melanomas (mainly on the foot). In conclusion, this study confirms that a more distal location of lower limb cutaneous melanoma is a relevant prognostic factor.Trial registration number NCT04625491 retrospectively registered.

Polarimetric calibration of a spectropolarimeter instrument with high precision: Sunrise chromospheric infrared spectropolarimeter (SCIP) for the sunrise iii balloon telescope.

The Sunrise chromospheric infrared spectropolarimeter (SCIP) installed in the international balloon experiment sunrise iii will perform spectropolarimetric observations in the near-infrared band to measure solar photospheric and chromospheric magnetic fields simultaneously. The main components of SCIP for polarization measurements are a rotating wave plate, polarization beam splitters, and CMOS imaging sensors. In each of the sensors, SCIP records the orthogonal linearly polarized components of light. The polarization is later demodulated on-board. Each sensor covers one of the two distinct wavelength regions centered at 770 and 850 nm. To retrieve the proper circular polarization, the new parameter R, defined as the 45° phase shifted component of Stokes V in the modulation curve, is introduced. SCIP is aimed at achieving high polarization precision (1σ<3×10-4 of continuum intensity) to capture weak polarization signals in the chromosphere. The objectives of the polarization calibration test presented in this paper are to determine a response matrix of SCIP and to measure its repeatability and temperature dependence to achieve the required polarization precision. Tolerances of the response matrix elements were set after considering typical photospheric and chromospheric polarization signal levels. We constructed a feed optical system such that a telecentric beam can enter SCIP with the same f-number as the light distribution instrument of the sunrise iii telescope. A wire-grid linear polarizer and achromatic wave plate were placed before SCIP to produce the known polarization. The obtained response matrix was close to the values expected from the design. The wavelength and spatial variations, repeatability, and temperature dependence of the response matrix were confirmed to be smaller than tolerances.

Probing Upflowing Regions in the Quiet Sun and Coronal Holes.

Recent observations from Parker Solar Probe have revealed that the solar wind has a highly variable structure. How this complex behaviour is formed in the solar corona is not yet known, since it requires omnipresent fluctuations, which constantly emit material to feed the wind. In this article we analyse 14 upflow regions in the solar corona to find potential sources for plasma flow. The upflow regions are derived from spectroscopic data from the EUV Imaging Spectrometer (EIS) on board Hinode determining their Doppler velocity and defining regions which have blueshifts stronger than - 6 km s - 1 . To identify the sources of these blueshift data from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI), on board the Solar Dynamics Observatory (SDO), and the X-ray Telescope (XRT), on board Hinode, are used. The analysis reveals that only 5 out of 14 upflows are associated with frequent transients, like obvious jets or bright points. In contrast to that, seven events are associated with small-scale features, which show a large variety of dynamics. Some resemble small bright points, while others show an eruptive nature, all of which are faint and only live for a few minutes; we cannot rule out that several of these sources may be fainter and, hence, less obvious jets. Since the complex structure of the solar wind is known, this suggests that new sources have to be considered or better methods used to analyse the known sources. This work shows that small and frequent features, which were previously neglected, can cause strong upflows in the solar corona. These results emphasise the importance of the first observations from the Extreme-Ultraviolet Imager (EUI) on board Solar Orbiter, which revealed complex small-scale coronal structures.

EDA, EDAR, EDARADD and WNT10A allelic variants in patients with ectodermal derivative impairment in the Spanish population.

BACKGROUND: Ectodermal dysplasias (ED) are a group of genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives. An attenuated phenotype is considered a non-syndromic trait when the patient is affected by only one impaired ectodermal structure, such as in non-syndromic tooth agenesis (NSTA) disorder. Hypohidrotic ectodermal dysplasia (HED) is the most highly represented ED. X-linked hypohidrotic ectodermal dysplasia (XLHED) is the most common subtype, with an incidence of 1/50,000-100,000 males, and is associated with the EDA gene (Xq12-q13.1); the dominant and recessive subtypes involve the EDAR (2q13) and EDARADD (1q42.3) genes, respectively. The WNT10A gene (2q35) is associated more frequently with NSTA. Our goal was to determine the mutational spectrum in a cohort of 72 Spanish patients affected by one or more ectodermal derivative impairments referred to as HED (63/72) or NSTA (9 /72) to establish the prevalence of the allelic variants of the four most frequently associated genes. Sanger sequencing of the EDA, EDAR, EDARADD and WNT10A genes and multiplex ligation-dependent probe amplification (MLPA) were performed. RESULTS: A total of 61 children and 11 adults, comprising 50 males and 22 females, were included. The average ages were 5.4 and 40.2 years for children and adults, respectively. A molecular basis was identified in 51/72 patients, including 47/63 HED patients, for whom EDA was the most frequently involved gene, and 4/9 NSTA patients, most of whom had variants of WNT10A. Among all the patients, 37/51 had variants of EDA, 8/51 had variants of the WNT10A gene, 4/51 had variants of EDAR and 5/51 had variants of EDARADD. In 42/51 of cases, the variants were inherited according to an X-linked pattern (27/42), with the remaining showing an autosomal dominant (10/42) or autosomal recessive (5/42) pattern. Among the NSTA patients, 3/9 carried pathogenic variants of WNT10A and 1/9 carried EDA variants. A total of 60 variants were detected in 51 patients, 46 of which were different, and out of these 46 variants, 12 were novel. CONCLUSIONS: This is the only molecular study conducted to date in the Spanish population affected by ED. The EDA, EDAR, EDARADD and WNT10A genes constitute the molecular basis in 70.8% of patients with a 74.6% yield in HED and 44.4% in NSTA. Twelve novel variants were identified. The WNT10A gene has been confirmed as the second molecular candidate that has been identified and accounts for one-half of non-EDA patients and one-third of NSTA patients. Further studies using next generation sequencing (NGS) will help to identify other contributory genes in the remaining uncharacterized Spanish patients.

NKG2D Polymorphism in Melanoma Patients from Southeastern Spain.

BACKGROUND: Natural killer (NK) and CD8+ T cells are involved in the immune response against melanoma. C-Type lectin-like NK cell receptors are located in the Natural Killer Complex (NKC) region 12p13.2-p12.3 and play a critical role in regulating the activity of NK and CD8+ T cells. An association between polymorphisms in the NKC region, including the NKG2D gene and NKG2A promoter, and the risk of cancer has been previously described. The aim of this study was to analyze the association of polymorphisms in the NKC region with cutaneous melanoma in patients from southeastern Spain. METHODS: Seven single-nucleotide polymorphisms (SNPs) in the NKG2D gene (NKC3,4,7,9,10,11,12), and one SNP in the NKG2A promoter (NKC17) were genotyped by a TaqMan 5' Nuclease Assay in 233 melanoma patients and 200 matched healthy controls. RESULTS: A linkage disequilibrium analysis of the SNPs performed in the NKC region revealed two blocks of haplotypes (Hb-1 and Hb-2) with 14 and seven different haplotype subtypes, respectively. The third most frequent haplotype from the block Hb-2-NK3 (CAT haplotype)-was significantly more frequent on melanoma patients than on healthy controls (p = 0.00009, Pc = 0.0006). No further associations were found when NKC SNPs were considered independently. CONCLUSIONS: Our results suggest an association between NKG2D polymorphisms and the risk of cutaneous malignant melanoma.

Web Support for Weight-Loss Interventions: PREDIRCAM2 Clinical Trial Baseline Characteristics and Preliminary Results.

An ongoing clinical trial is testing the efficacy of web telematic support in a structured program for obesity treatment and diabetes prevention. Participants were recruited from two tertiary-care hospitals and randomized to receive either a telematic intervention (TI) supported by PREDIRCAM2 web platform or a non-telematic intervention (NTI). All receive 1-year follow-up. Both interventions consist of tailored dietary and exercise prescriptions, based on a Mediterranean dietary pattern and general WHO exercise recommendations for adults. At 6 months, both groups have received 7 contacts, 3 exclusively telematic for the TI group. This is a preliminary result intention-to-treat analysis. One hundred eighty-three participants were recruited, with a mean body mass index of 34.75 ± 2.75 kg/m2. General dropout rate at 6 months was 26.8%. Weight changes were statistically significant at months 3 and 6 compared to baseline, -2.915 ± 0.24 kg, -3.29 ± 0.36 kg, respectively (P < 0.001), but not statistically significant between the 3- and 6-month time points -0.37 ± 0.21 kg (P = 0.24). Mean group differences showed that the TI group lost 1.61 ± 1.88 kg more than the NTI group (P = 0.39). Waist, waist/hip ratio, resting heart rate, blood pressure, HbA1c, and low-density lipoprotein cholesterol also showed statistically significant changes at 6 months, with no significant differences between groups. Weight loss in the TI group shows similar results as the usual care NTI group for weight loss and control of obesity comorbidities. At completion of the clinical trial, these results will be reevaluated to assess the potential role of web support in weight-loss maintenance and its cost-effectiveness.

Design and Technical Validation of a Telemedicine Service for Rural Healthcare in Ecuador.

BACKGROUND: Telemedicine is becoming increasingly important in Ecuador, especially in areas such as rural primary healthcare and medical education. Rural telemedicine programs in the country need to be strengthened by means of a technological platform adapted to local surroundings and offering advantages such as access to specialized care, continuing education, and so on, combined with modest investment requirements. INTRODUCTION: This present article presents the design of a Telemedicine Platform (TMP) for rural healthcare services in Ecuador and a preliminary technical validation with medical students and teachers. MATERIALS AND METHODS: An initial field study was designed to capture the requirements of the TMP. In a second phase, the TMP was validated in an academic environment along three consecutive academic courses. Assessment was by means of user polls and analyzing user interactions as registered automatically by the platform. The TMP was developed using Web-based technology and open code software. RESULTS: One hundred twenty-four students and 6 specialized faculty members participated in the study, conducting a total of 262 teleconsultations of clinical cases and 226 responses, respectively. CONCLUSION: The validation results show that the TMP is a useful communication tool for the documentation and discussion of clinical cases. Moreover, its usage may be recommended as a teaching methodology, to strengthen the skills of medical undergraduates. The results indicate that implementing the system in rural healthcare services in Ecuador would be feasible.

MHC class I chain-related gene a diversity in patients with cutaneous malignant melanoma from southeastern Spain.

A limited number of studies have been performed so far on the polymorphism in the transmembrane region (exon 5) of the major histocompatibility complex class I chain-related gene A (MICA) in patients with melanoma. However, the influence of MICA polymorphism in extracellular domains (exons 2, 3, and 4) has not been investigated on melanoma disease. This study aims to characterize the influence of extracellular MICA polymorphism, and its previously described linkage disequilibrium with HLA-B locus, on patients with cutaneous melanoma from southeastern Spain. For this purpose, MICA and HLA-B genotyping was performed in 233 patients and 200 ethnically matched controls by luminex technology. Patients were classified according to the presence of methionine or valine at codon 129 of MICA gene. We found a high frequency of MICA(*)009 in melanoma patients compared with controls (P = 0.002, Pc = 0.03). Our results also showed an association between MICA(*)009 and HLA-B(*)51 alleles in both patients and controls. This association was stronger in patients than controls (P = 0.015). However, a multivariate logistic regression model showed that neither MICA(*)009 nor the combination MICA(*)009/HLA-B(*)51 was associated with melanoma susceptibility. No relationship was observed between MICA-129 dimorphism and melanoma nor when MICA polymorphism was evaluated according to clinical findings at diagnosis.

PREDIRCAM eHealth platform for individualized telemedical assistance for lifestyle modification in the treatment of obesity, diabetes, and cardiometabolic risk prevention: a pilot study (PREDIRCAM 1).

BACKGROUND: Healthy diet and regular physical activity are powerful tools in reducing diabetes and cardiometabolic risk. Various international scientific and health organizations have advocated the use of new technologies to solve these problems. The PREDIRCAM project explores the contribution that a technological system could offer for the continuous monitoring of lifestyle habits and individualized treatment of obesity as well as cardiometabolic risk prevention. METHODS: PREDIRCAM is a technological platform for patients and professionals designed to improve the effectiveness of lifestyle behavior modifications through the intensive use of the latest information and communication technologies. The platform consists of a web-based application providing communication interface with monitoring devices of physiological variables, application for monitoring dietary intake, ad hoc electronic medical records, different communication channels, and an intelligent notification system. A 2-week feasibility study was conducted in 15 volunteers to assess the viability of the platform. RESULTS: The website received 244 visits (average time/session: 17 min 45 s). A total of 435 dietary intakes were recorded (average time for each intake registration, 4 min 42 s ± 2 min 30 s), 59 exercises were recorded in 20 heart rate monitor downloads, 43 topics were discussed through a forum, and 11 of the 15 volunteers expressed a favorable opinion toward the platform. Food intake recording was reported as the most laborious task. Ten of the volunteers considered long-term use of the platform to be feasible. CONCLUSIONS: The PREDIRCAM platform is technically ready for clinical evaluation. Training is required to use the platform and, in particular, for registration of dietary food intake.

Cutaneous leishmaniasis in a patient receiving infliximab.

Leishmaniasis is endemic in the Mediterranean region, and the prevalence of latent infection in this area is high. Treatment with tumour necrosis factor (TNF) antagonists represents a major breakthrough in the treatment of several inflammatory diseases, including psoriasis. Reports describing opportunistic leishmaniasis in European patients treated with TNF-α antagonist drugs are rapidly accumulating. We describe a case of cutaneous leishmaniasis in a patient treated with infliximab and corticosteroids.

Empyema and lung abscess as complication of a perforated appendicitis in a pregnant woman.

INTRODUCTION: The development of empyema as a result of an intra-abdominal pathology is a rare condition. PRESENTATION OF CASE: We present a 31-year-old woman at 28 weeks' gestation who was referred to our hospital with diagnosis of pneumonia with pleural effusion. She presented with signs of septicemia and fetal distress. A thoracic-abdominal-pelvic CT-scan showed a right pleural effusion with a retroperitoneal collection in contact with the pleural space. Due to her critical condition, immediate surgical exploration and pregnancy interruption was decided. The fetus was delivered by cesarean with satisfactory vitality. After abdominal exploration, a retrocecal appendicular abscess was evidenced and appendectomy was performed. Subsequently, the right chest was accessed through a posterolateral thoracotomy. An empyema with lung abscess and purulent fluid accessing from the retroperitoneum at the posterior pleural space was found. Due to parenchymal compromise, a right inferior lobectomy was performed. The patient had an uneventful recovery and was discharged at postoperative day 10. DISCUSSION: A septic condition in a pregnant patient with significant thoraco-abdominal infection requires an aggressive approach, with interruption of pregnancy and urgent exploration of the chest and abdomen. CONCLUSION: When an empyema is developed in absence of lung disease or other intrathoracic cause, intra-abdominal origin should be considered.

Nuevo Metodo de Regeneracion hepatica / New Method of Hepatic Regeneration

La insuficiencia hepática postoperatoria (IHP) es la complicación más temida y severa tras de una resección hepática extensa. Presentamos una técnica quirúrgica innovadora para el tratamiento de una paciente con cáncer colorrectal y secundarismo hepático inicialmente irresecable. Tras de completar quimioterapia neoadyuvante se decide cirugía simultánea. Se realizó hemicolectomía izquierda y limpieza de las metástasis del hígado izquierdo. Debido a que el remanente hepático futuro (RHF) era insuficiente, se realizó partición hepática in situ y ligadura portal derecha. Al 6.° día postoperatorio una TC volumétrica evidenció aumento mayor al 40% del RHF. Se le completó la hepatectomía derecha y fue externada al 11.° día postoperatorio. La técnica permitió un rápido crecimiento del RHF, superando lo reportado mediante oclusión portal. De corroborarse estos hallazgos en futuros estudios, esta revolucionaria técnica permitiría el tratamiento quirúrgico en dos etapas de pacientes con enfermedad hepática inicialmente irresecable durante una misma internación y sin IHP (AU)

Postoperative liver failure (PLF) is the most feared and serious complication after extensive liver resections. We present an innovative surgical technique for the treatment of a patient with colorectal cancer and initially unresectable liver metastases. After completing neoadjuvant chemotherapy, it was decided to perform simultaneous surgery. A left hemicolectomy and cleaning of the metastases in the left liver were performed. As the future liver remnant (FLR) was insufficient, it was decided to perform an in situ liver split and a right portal vein ligation. On the 6th day after the surgery a volumetric CT showed an increase greater than 40% of the FLR. The right hepatectomy was completed and the patient was discharged on the 11th day after surgery. The technique induced a rapid growth of the FLR, exceeding that reported using portal occlusion. If these findings are corroborated in future studies, this revolutionary technique could enable surgery to be performed in two stages on patients with initially unresectable liver disease during the same hospital admission and without PLF (AU)

[New method of hepatic regeneration]. / Nuevo Metodo de Regeneracion hepatica.

Postoperative liver failure (PLF) is the most feared and serious complication after extensive liver resections. We present an innovative surgical technique for the treatment of a patient with colorectal cancer and initially unresectable liver metastases. After completing neoadjuvant chemotherapy, it was decided to perform simultaneous surgery. A left hemicolectomy and cleaning of the metastases in the left liver was performed. As the future liver remnant (FLR) was insufficient, it was decided to perform an in situ liver split and a right portal vein ligation. On the 6(th) day after the surgery a volumetric CT showed an increase greater than 40% of the FLR. The right hepatectomy was completed and the patient was discharged on the 11(th) day after surgery. The technique induced a rapid growth of the FLR, exceeding that reported using portal occlusion. If these findings are corroborated in future studies, this revolutionary technique could enable surgery to be performed in two stages on patients with initially unresectable liver disease during the same hospital admission and without PLF.

Localización anatómica del tumor primario como variable a considerar en la biopsia selectiva del ganglio centinela del melanoma cutáneo / Anatomical location of the primary tumor as a variable to be considered in sentinel node biopsy of cutaneous melanoma

Introducción. La localización anatómica del melanoma cutáneo se ha considerado como un factor pronóstico independiente. En este trabajo se trata de comprobar si la localización del tumor primario influye en la detección del ganglio centinela en el melanoma cutáneo. Pacientes y método. Se ha estudiado a 212 pacientes con melanoma cutáneo primario (96 en los miembros, 89 en el tronco y 27 en la cabeza o el cuello) en los que se realizó la biopsia del ganglio centinela. Se estudió la adecuada localización gammagráfica y quirúrgica y se compararon las variables epidemiológicas e histopatológicas, el número de drenajes por lesión y de ganglios centinela por drenaje y la positividad del estudio de los ganglios. Para los drenajes procedentes de los tumores de la cabeza y el cuello se estudió el drenaje hacia territorio de la glándula salival como variable relacionada con la localización del ganglio centinela. Resultados. La localización fue peor para los tumores de cabeza y cuello (88,8%), tanto gammagráfica (p <0,001) como quirúrgica (p <0,0005), especialmente para los ganglios adyacentes a las glándulas salivales (p <0,0005). Los melanomas del tronco presentan un mayor número y variabilidad en sus drenajes (p <0,0005), aunque sin diferencias en el número de ganglios centinela por drenaje linfático (p = 0,455). Conclusiones. Los melanomas cutáneos localizados en la cabeza y el cuello presentaron más fallos en la identificación del ganglio centinela. La localización del ganglio centinela adyacente a una glándula salival es un factor que influye en su adecuada detección. Los melanomas cutáneos del tronco presentan un mayor número de drenajes por lesión que los localizados en las extremidades o en la cabeza y el cuello (AU)

Introduction. The anatomical location of cutaneous melanoma has been suggested to be an independent prognostic factor. The aim of the present study was to determine whether the location of the primary tumor influences sentinel node detection in cutaneous melanoma. Patients and method. Two hundred twelve patients with primary cutaneous melanoma (96 of the limbs, 89 of the trunk and 27 of the head or neck) who underwent sentinel lymph node biopsy were studied. Adequate lymphoscintigraphic and surgical localization was evaluated and epidemiological and histopathological variables, the number of lymph nodes draining the site of the primary lesion, sentinel nodes per drainage basin, and tumor-positive nodes were compared. Results. Localization was less successful for tumors of the head and neck (88.8%), both with lymphoscintigraphy (P<.001) and surgery (P<.0005), especially for lymph nodes adjacent to salivary glands (P<.0005). Melanomas of the trunk showed a greater number of nodes per lesion and wider variability in drainage pathways (P<.0005), although there were no differences in the number of sentinel nodes per drainage basin (P=0455). Conclusions. Sentinel node detection with less successful in cutaneous melanomas located in the head and neck. Location of the sentinel node adjacent to a salivary gland is a factor that influences its detection. Cutaneous melanomas of the trunk showed a higher number of draining nodes per lesion than those located in the limbs or head and neck (AU)

[Anatomical location of the primary tumor as a variable to be considered in sentinel node biopsy of cutaneous melanoma]. / Localización anatómica del tumor primario como variable a considerar en la biopsia selectiva del ganglio centinela del melanoma cutáneo.

INTRODUCTION: The anatomical location of cutaneous melanoma has been suggested to be an independent prognostic factor. The aim of the present study was to determine whether the location of the primary tumor influences sentinel node detection in cutaneous melanoma. PATIENTS AND METHOD: Two hundred twelve patients with primary cutaneous melanoma (96 of the limbs, 89 of the trunk and 27 of the head or neck) who underwent sentinel lymph node biopsy were studied. Adequate lymphoscintigraphic and surgical localization was evaluated and epidemiological and histopathological variables, the number of lymph nodes draining the site of the primary lesion, sentinel nodes per drainage basin, and tumor-positive nodes were compared. RESULTS: Localization was less successful for tumors of the head and neck (88.8%), both with lymphoscintigraphy (P<.001) and surgery (P<.0005), especially for lymph nodes adjacent to salivary glands (P<.0005). Melanomas of the trunk showed a greater number of nodes per lesion and wider variability in drainage pathways (P<.0005), although there were no differences in the number of sentinel nodes per drainage basin (P=.455). CONCLUSIONS: Sentinel node detection with less successful in cutaneous melanomas located in the head and neck. Location of the sentinel node adjacent to a salivary gland is a factor that influences its detection. Cutaneous melanomas of the trunk showed a higher number of draining nodes per lesion than those located in the limbs or head and neck.

Carcinoma de mama en varón / Male breast cancer

Se presentan 2 pacientes en los que, tras la biopsia de sus lesiones cutáneas mamarias, se diagnosticaron sendos carcinomas, en uno trabecular y en el otro ductal infiltrante. En ambos casos el motivo de consulta original fue totalmente distinto, y las lesiones mamarias fueron hallazgos casuales tras la adecuada exploración física. Los factores de riesgo relacionados eran un traumatismo mamario en el primero y la existencia de enfermedad prostática previa, obesidad y edad avanzada en el segundo. El cáncer de mama en el varón es poco frecuente. Aunque en el 25% de los casos la primera manifestación suele ser cutánea, ésta no suele ser el motivo de consulta. El diagnóstico precoz mejora el pronóstico, al igual que en la mujer, por lo que es necesario conocer las manifestaciones cutáneas, pues éstas pueden constituir el signo fundamental para establecer un rápido diagnóstico e instaurar un tratamiento adecuado (AU)

Biopsia selectiva del ganglio centinela en el melanoma mediante localización con linfogammagrafía preoperatoria y sonda de detección gamma intraoperatoria / Sentinel node biopsy in melanoma using preoperative lymphoscintigraphy and intraoperative handheld gamma probe

FUNDAMENTOS: Se refiere la experiencia para la detección del ganglio centinela en el melanoma utilizando únicamente la linfogammagrafía preoperatoria y trazador radiactivo con sonda de detección de radiación gamma intraoperatoria. PACIENTES Y MÉTODO: Se estudió a 60 pacientes con melanoma en estadios I-II, a quienes se realizó biopsia selectiva del ganglio centinela mediante su localización con sulfuro coloidal marcado con Tc-99m. A todos se les efectuó una gammagrafía preoperatoria y se trató de localizar el ganglio centinela con una sonda de detección de radiación gamma. Se han estudiado los resultados de la gammagrafía preoperatoria, la eficacia técnica en la localización intraoperatoria, así como los resultados anatomopatológicos y del seguimiento de los pacientes. RESULTADOS: La tasa de detección preoperatoria fue del 98,3 por ciento, con una media de 1,17 drenajes por lesión, siendo múltiples especialmente en los melanomas de tronco. La localización intraoperatoria (eficacia técnica) fue del 98,48 por ciento, con dificultades para su localización en la región parotídea. En el estudio histopatológico fueron fundamentales las técnicas de inmunohistoquímica con HMB45, resultando positivos un 10 por ciento, por lo que se evitó la linfadenectomía en el 90 por ciento de los casos. No se observaron recidivas y las metástasis se dieron en casos inabordables. La morbilidad de la técnica fue significativamente menor que la de la linfadenectomía. CONCLUSIONES: La linfogammagrafía preoperatoria y el uso de sonda de detección de radiación gamma, como técnica de localización del ganglio centinela en el melanoma, tienen una elevada eficacia técnica, permiten detectar drenajes múltiples y posibilitan un abordaje muy selectivo y con disección mínima (AU)