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BACKGROUND/OBJECTIVES: Little is known about the dermoscopic features of atypical fibroxanthoma. METHODS: This was a case-control study. Atypical fibroxanthoma lesions were compared with a control group with non-melanoma skin cancer. RESULTS: Altogether 40 atypical fibroxanthoma were collected. Most developed in men (93%), appearing mainly as nodular (63%), amelanotic (93%) and ulcerated (78%) lesions. Most lesions were located on the scalp (55%) and the ears (13%). Dermoscopically, most atypical fibroxanthoma displayed red (83%) and white (70%) structureless areas and irregular linear vessels (43%). A series of features achieved statistical significance when comparing atypical fibroxanthoma with non-melanoma skin cancer. The presence of red and white structureless areas and white lines, and the absence of yellowish-white opaque scales, hairpin vessels and arborising vessels were predictive of atypical fibroxanthoma in univariate analysis. However, when squamous cell carcinoma was excluded from the analysis, none of the criteria achieved statistical significance. When basal cell carcinoma was excluded, three variables achieved statistical significance in predicting atypical fibroxanthoma: red, structureless areas, the absence of opaque yellowish-white scales and absence of white circles. CONCLUSIONS: Atypical fibroxanthomas seem to be barely distinguishable from basal cell carcinoma dermoscopically, but they are more easily distinguishable from a well to moderately differentiated squamous cell carcinoma. A histopathological examination is needed for the final diagnosis.
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Carcinoma Basocelular/diagnóstico por imagen , Carcinoma de Células Escamosas/diagnóstico por imagen , Dermoscopía , Fibroma/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Xantomatosis/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Fibroma/patología , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Sociedades Médicas , Xantomatosis/patologíaRESUMEN
We present a unique case of separate and independent adjacent fibroepitheliomas of Pinkus (FeP) arising from the umbilicus in an 83-year-old man. Of further interest, one is pigmented and the other nonpigmented. Clinical, dermatoscopic and histopathological images are provided. A review of the published literature is undertaken to attempt to assess the incidence of pigmented versus nonpigmented FeP. Of 24 published FeP cases, 10 (41.7%) have been pigmented. Thus to date pigmented FeP comprise approaching one-half of all reported cases.
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We present a case report of a microcystic adnexal carcinoma on the cheek of a 67-year-old man. Clinical, dermatoscopic and dermatopathologic images are presented. A search of the literature has not discovered any previously published dermatoscopy images of microcystic adenexal carcinoma.
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We present a case of a clonal nevus arising from a previously banal melanocytic nevus over a 15-month period on the central back of a 30-year-old woman in a primary care skin cancer practice in Melbourne, Australia. Clinical, dermatoscopic and dermatopathologic images are presented. A search of the literature has discovered no previously published dermatoscopy images of an evolving clonal nevus.
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The Canadian population is currently subject to low, chronic lead exposure and an understanding of its effects is of great significance to the population's health. Such low exposure is difficult to measure directly; approximation by physiologically based modeling may provide a preferable approach to population analysis. The O'Flaherty model of lead kinetics is based on an age-dependent approach to human growth and development and devotes special attention to bone turnover rates. Because lead is a bone-seeking element, the model was deemed ideal for such an analysis. Sample from 263 individuals of various ages from the Greater Toronto Area were selected to evaluate the applicability of the current version of the O'Flaherty model to populations with low lead exposure. For each individual, the input value of lead exposure was calibrated to match the output value of cortical bone lead to the individual's measured tibia lead concentration; the outputs for trabecular bone, blood, and plasma lead concentrations obtained from these calibrations were then compared with the subjects' measured calcaneus, blood, and serum lead concentrations, respectively. This indicated a need for revision of the model parameters; those for lead binding in blood and lead clearance from blood to bone were adjusted and new outputs were obtained in the same fashion as before. Model predictions of trabecular lead concentration did not agree with measurements in the calcaneus. The outputs for blood and plasma lead concentrations were highly scattered and, on an individual level, inconsistent with corresponding measurements; however, the general trends of the outputs matched those of the measurements reasonably well, which indicates that the revised blood lead binding and lead clearance parameters may be useful in future studies. Overall, the analysis showed that with the revisions to the model discussed here, the model should be a useful tool in the analysis of human lead kinetics and body burden in populations characterized by low, chronic exposure to lead from the general environment.
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Exposición a Riesgos Ambientales/estadística & datos numéricos , Plomo/metabolismo , Modelos Estadísticos , Tibia/metabolismo , Adulto , Carga Corporal (Radioterapia) , Canadá , Femenino , Humanos , Cinética , Masculino , Persona de Mediana Edad , Proyectos PilotoRESUMEN
We present a case report of an atypical fibroxanthoma on the cheek of a 73-year-old man. Clinical, dermatoscopic and dermatopathologic images are presented.
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A (109)Cd K X-ray fluorescence (KXRF) measurement system consisting of four detectors in clover-leaf geometry is a non-invasive, low-radiation-dose method of measuring bone lead concentration. Its high precision in estimating the bone lead content makes it a promising tool for the determination of the low levels of lead currently found in the general population. After developing the clover-leaf geometry system, the system was used for the first time in a major survey in 2008 to measure the lead levels of 497 smelter employees (an occupationally exposed group with high lead levels). Since the delivered effective dose of the bone lead system in clover-leaf geometry is small (on the order of nSv), the technique can be used to measure the bone lead of sensitive populations such as the elderly and children. This detector system was used from 2009 to 2011, in a pilot study that measured the bone lead concentration of 263 environmentally exposed individuals (termed the EG group) residing in Toronto, Ontario, Canada. In this paper, the factors that influence uncertainties in lead content in tibia (cortical bone) and calcaneus (trabecular bone) are discussed based on gender, age, and body mass index (BMI) by using analysis of variance (ANOVA) and multiple linear regression models. Results from the two study groups (the EG group versus the occupationally exposed smelter employees) are compared where appropriate (i.e. for males older than 20). Results from univariate analyses showed that females have higher tibia uncertainty compared to males. We observed significant differences for both calcaneus and tibia uncertainty measures (p < 0.0005) among different age groups, where the uncertainties were highest in the lowest age group (<11 years). Lastly, and perhaps most significantly, we found that the product of source activity and measurement time influenced the precision of measurements greatly, and that this factor alone could account for the higher uncertainties observed for the male cohort of the EG group versus the smelter employees.
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Huesos/química , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Plomo/análisis , Adolescente , Adulto , Anciano , Análisis de Varianza , Canadá , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Espectrometría por Rayos XRESUMEN
We present a case report of a 3.5 mm diameter superficial spreading melanoma on the upper back of a 27-year-old woman, signed out as Clark level 2, Breslow thickness 0.2 mm with regression to 0.45 mm. The patient, with Fitzpatrick type 1 skin and minimal actinic damage, had presented for a routine skin check with no previous history of skin cancers. At the age of 17 she had received chemotherapy and radiotherapy for Ewing's sarcoma of the right hip with pulmonary metastases. The skin lesion was assessed as dermatoscopically symmetrical and was not predicted as a melanoma by any algorithmic method. The provisional diagnosis of melanoma was made on the basis that this lesion was completely different in dermatoscopic pattern to her other nevi, a dermatoscopic "ugly duckling" lesion. We draw attention to the recently established link between defects in the STAG2 gene and Ewing's sarcoma, glioblastoma and melanoma.
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A case of balloon cell melanoma encountered in a primary care skin cancer practice in Melbourne, Australia is presented. The presenting lesion was 6 mm in diameter, ulcerated, non-pigmented and without any algorithmic clues to melanoma. However the presence of terminal hairs caused the clinician to suspect that it was melanocytic. The lesion was reported as a balloon cell melanoma, Clark level 4, Breslow thickness 2 mm with a mitotic index of 4 per square mm. This is an extremely rare melanoma subtype. Author DW has encountered only two cases in a career involving in excess of one million signed out dermatopathology reports. A search of the literature has not discovered any previously published dermatoscopy images of a balloon cell melanoma.
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Several studies with animals have shown that even low and medium prenatal and postnatal exposure to methylmercury (MeHg) can result in locomotor, motor coordination and learning deficits. However, some behavioural effects of MeHg remain controversial and the methods to model human MeHg exposure in animal still remain to be optimized. We investigated the neurobehavioral effects of two different patterns of MeHg exposure. MeHg was given mixed in palatable food that mice readily ate. For the first pattern (chronic group), C57BL/6 mice dams were given 1.4 microg/g body weight (BW)/day (n=20) throughout gestation mixed in palatable food. For the second pattern (bolus) dams were given 6.0 microg/g BW/day mixed in palatable food on gestation day 12 and 16 together with a lower chronic dose of 0.85 microg/g BW/day mixed in palatable food on all remaining gestation days (n=20). Day 12 and 16 were chosen because neuron proliferation and the start of migration for many brain regions occur during that period. Behavioural testing on weanling animals started at 8 weeks. Both the chronic and bolus groups showed an impairment of working memory and visual spatial ability in the radial arm maze task. Other tests did not provide clear evidence that methylmercury exposure had significant adverse effects on locomotor activity, motor coordination or emotional reactivity. However, the chronic groups had a tendency for lower performance in most tests including activity in Skinner box and open field trials, as well as a higher number of anxiety-like behaviors. Chronic exposure to lower levels of MeHg combined to acute exposure with high levels of a few days during gestation appears to be less damaging than chronic exposure to slightly higher levels without acute MeHg exposure even though, equal amounts were administered during gestation. Possibly, as indicated by preliminary data, the relatively larger impact of chronic administration of a higher daily dose could be the consequence of a higher brain MeHg burden in pups compared to brain MeHg levels in the pups from dams receiving a smaller daily dose with 2 large doses on gestation day 12 and 16. Alternatively, bolus MeHg could have had a larger impact if administered on different gestation days when some neural development processes are more sensitive to MeHg.