Field cancerization: Definition, epidemiology, risk factors, and outcomes.

Field cancerization was first described in 1953 when pathologic atypia was identified in clinically normal tissue surrounding oropharyngeal carcinomas. The discovery of mutated fields surrounding primary tumors raised the question of whether the development of subsequent tumors within the field represented recurrences or additional primary tumors. Since this initial study, field cancerization has been applied to numerous other epithelial tissues, including the skin. Cutaneous field cancerization occurs in areas exposed to chronic ultraviolet radiation, which leads to clonal proliferations of p53-mutated fields and is characterized by multifocal actinic keratoses, squamous cell carcinomas in situ, and cutaneous squamous cell carcinomas. In the first article in this continuing medical education series, we define field cancerization, review the available grading systems, and discuss the epidemiology, risk factors, and outcomes associated with this disease.

Predictors of Beagley-Gibson skin cast grade in older adults.

BACKGROUND AND PURPOSE: The Beagley-Gibson (BG) grading system utilizes microtopographical skin changes to generate an individualized, objective estimate of cumulative, lifetime ultraviolet radiation (UVR) exposure. However, predictors of BG grade are ill-defined, particularly in older populations. The aim of this cross-sectional study was to describe the factors associated with skin damage as measured by the BG method in 835 community-dwelling older adults. METHODS: Study participants aged 53-83 years had silicone casts taken from the dorsum of both hands and graded by the BG method. Lifetime sun exposure, skin phenotypic traits and smoking status were assessed by questionnaire. 25-hydroxyvitamin D and melanin density were measured using radioimmunoassay and spectrophotometry, respectively. Ordered logistic regression was used to compute a single odds ratio (OR) by taking BG grade as the outcome variable. RESULTS: Higher 25-hydroxyvitamin D was associated with increasing BG grade (OR = 1.39, P = 0.02) in adjusted analysis. Age (OR = 1.14, P < 0.001), occupational sun exposure (OR = 1.62, P < 0.001), ability to tan (OR = 1.40, P < 0.001), melanin density (OR=0.79, P = 0.001), lifetime leisure time sun exposure (OR = 1.21, P = 0.004), current smoking (OR = 1.82, P = 0.007), propensity to sunburn (OR = 1.18, P = 0.016), and waist-hip ratio (OR = 1.10, P = 0.02) were independent predictors of BG grade. Hair colour, number of sunburns, body mass index and gender were not independent predictors of BG grade. CONCLUSIONS: Beagley-Gibson skin cast grade is a biologically relevant marker of UVR exposure in older adults influenced by both intrinsic and extrinsic factors.

Clinical and dermoscopic characteristics of melanomas on nonfacial chronically sun-damaged skin.

BACKGROUND: Melanomas on chronically sun-damaged skin (CSDS) can be difficult to identify and often manifest morphologic features that overlap with benign lesions. OBJECTIVE: We describe and analyze the clinical and dermoscopic characteristics of melanomas on nonfacial CSDS. METHODS: Melanoma cases on nonfacial CSDS were retrospectively identified from the biopsy specimen logs of 6 melanoma clinics. Clinical and dermoscopic images were combined into 1 database. Demographics, clinical, dermoscopic, and histopathologic information were analyzed. Descriptive frequencies were calculated. RESULTS: One hundred eighty-six cases met the inclusion criteria: 142 melanomas in situ (76%) and 39 invasive (21%; mean thickness, 0.49 mm). Lentigo maligna was the most common histopathologic subtype (n = 76; 40.9%). The most frequent dermoscopic structures were granularity (n = 126; 67.7%) and angulated lines (n = 82; 44%). Vascular structures were more frequent in invasive melanomas (56% vs 12% of in situ melanomas). Most manifested 1 of 3 dermoscopic patterns: patchy peripheral pigmented islands, angulated lines, and tan structureless with granularity pattern. LIMITATIONS: This was a retrospective study, and evaluators were not blinded to the diagnosis. In addition, interobserver concordance and sensitivity and specificity for dermoscopic structures were not evaluated. CONCLUSION: Outlier lesions manifesting dermoscopic structures, such as granularity, angulated lines, or vessels and any of the 3 described dermoscopic patterns should raise suspicion for melanoma.

Successful treatment of early cutaneous squamous cell carcinoma with hypofractionated radiation therapy in an African lion (Panthera leo).

Cutaneous squamous cell carcinoma (SCC) is a slow growing but locally invasive neoplasm, most commonly caused by prolonged exposure to ultraviolet (UV) radiation. Whilst SCC accounts for 15% of skin tumours in domesticated cats, cutaneous SCC in non-domesticated felids (apart from captive snow leopards) appears to be uncommon, with only three reports in the literature to date. In this report, a captive African lion (Panthera leo) presented with two ulcerative lesions on the nasal planum. Histopathology of the lesions revealed epidermal keratinocyte dysplasia and neoplastic basal- and supra-basal epithelial cells with dyskeratosis and evidence of basement membrane breaching and dermal invasion, consistent with a diagnosis of SCC. There was also evidence of laminar fibrosis and inflammation of the subjacent dermis suggesting that the SCC most likely resulted from UV-induced neoplastic transformation of the epidermal squamous epithelium following actinic keratosis. The lion was treated with hypofractionated radiation therapy and remained in remission until his death (euthanised 17 months later because of age-related chronic renal failure). This is the first report of cutaneous SCC in a lion with evidence of actinic damage and resolution after radiation therapy.

Caracterización clínico-epidemiológica de pacientes con daño actínico crónico. Cochabamba, Bolivia / Clinical-epidemiological characterization of patients with chronic actinic damage. Cochabamba, Bolivia

RESUMEN Introducción: el daño actínico crónico es un grupo de alteraciones en la estructura, función y apariencia de la piel como resultado de la exposición no controlada a las radiaciones ultravioletas. Puede provocar el cáncer de piel. Objetivo: caracterizar a los pacientes con daño actínico crónico, atendidos en la consulta de Dermatología del Hospital Comunitario Valle Hermoso, en el departamento de Cochabamba, Bolivia. Materiales y métodos: se realizó un estudio clínico descriptivo, prospectivo, en un universo de 1 833 pacientes diagnosticados con daño actínico crónico, atendidos en la consulta de Dermatología del Hospital Comunitario Valle Hermoso, en Cochabamba, entre septiembre de 2017 y septiembre de 2018. Se evaluaron las variables edad, sexo, color y fototipo de piel, ocupación, uso de medios de protección solar, exposición a otro tipo de radiaciones, manifestaciones clínicas de fotodaño y altitud del lugar de residencia. Resultados: predominaron el grupo de edad de 25 a 59 años, el sexo femenino, el color de piel mestizo (77,08 %), el fototipo de piel IV (76,98 %) y la ocupación comerciante (72,56 %). La mayoría de los pacientes (82,7 %) no utilizaron medios de protección solar, y el 99,8 % no tuvieron exposición a otro tipo de radiaciones. Las lesiones por fotodaño que prevalecieron fueron melasma (83,03 %) y lentigos (12,22 %). El 99,29 % vivían en zonas de gran altitud. Conclusiones: se caracterizaron los pacientes con daño actínico crónico, obteniendo en algunas variables estudiadas resultados similares a los mencionados por otros investigadores (AU).

ABSTRACT Introduction: chronic actinic damage is a group of alterations in the structure, function, and appearance of the skin as a result of uncontrolled exposure to ultraviolet radiation. It can cause skin cancer. Objective: to characterize the patients with chronic actinic damage, treated at the Dermatology consultation of Valle Hermoso Community Hospital, in the department of Cochabamba, Bolivia. Materials and methods: a descriptive, prospective clinical study was conducted in a universe of 1,833 patients diagnosed with chronic actinic damage, treated at the Dermatology clinic of the Valle Hermoso Community Hospital, Cochabamba, between September 2017 and September 2018. The variables age, sex, skin color, skin phototype, occupation, use of sun protectors, exposure to other types of radiation, clinical manifestations of photodamage and altitude of the place of residence were evaluated. Results: the age group from 25 to 59 years, the female sex, mestizo skin color (77.08 %), the IV skin phototype (76.98 %) and merchant occupation (72.56 %) predominated. Most patients (82.7 %) did not use sun protection means, and 99.8 % had no other radiation exposure. The prevailing photodamage lesions were melasma (83.03 %) and lentigo (12.22 %). 99.29 % lived in high altitude areas. Conclusions: the patients with chronic actinic damage were characterized, obtaining in some variables studied results similar to those mentioned by other researchers (AU).

Solitary Keratoacanthoma Developing on the Abnormally Sun - exposed Labial Mucosa / 대한피부과학회지

The case of a 56-year-old woman with a keratoacarithoma(KA) of the labial mucosa is herein reported, The tumor was excised and the pathological features were characteristic of a KA, This case is reported because the oral mucosa is such an unexpected location for solitary KA and the labial mucosa of this patient received chronic actinic damage, which suggested an etiological relationship. Follow-up examination of the patient after four months showed no recurrence.