Paget's disease, described by Sir James Paget in 1874, is classified as mammary and extramammary. The mammary type is rare and often associated with intraductal cancer (93-100% of cases). It is more prevalent in postmenopausal women and it appears as an eczematoid, erythematous, moist or crusted lesion, with or without fine scaling, infiltration and inversion of the nipple. It must be distinguished from erosive adenomatosis of the nipple, cutaneous extension of breast carcinoma, psoriasis, atopic dermatitis, contact dermatitis, chronic eczema, lactiferous ducts ectasia, Bowen's disease, basal cell carcinoma, melanoma and intraductal papilloma. Diagnosis is histological and prognosis and treatment depend on the type of underlying breast cancer. Extramammary Paget's disease is considered an adenocarcinoma originating from the skin or skin appendages in areas with apocrine glands. The primary location is the vulvar area, followed by the perianal region, scrotum, penis and axillae. It starts as an erythematous plaque of indolent growth, with well-defined edges, fine scaling, excoriations, exulcerations and lichenification. In most cases it is not associated with cancer, although there are publications linking it to tumors of the vulva, vagina, cervix and corpus uteri, bladder, ovary, gallbladder, liver, breast, colon and rectum. Differential diagnoses are candidiasis, psoriasis and chronic lichen simplex. Histopathology confirms the diagnosis. Before treatment begins, associated malignancies should be investigated. Surgical excision and micrographic surgery are the best treatment options, although recurrences are frequent.

Background Oral isotretinoin (ISO) is the only drug which promotes prolonged remission

Background Dermoscopy has furthered advances in the differential diagnosis of longitudinal melanonychia; however, fewer details observed in the nail, as compared to skin lesions, make interpretation difficult.Methods Ten cases of longitudinal melancholia, from several etiologies, were submitted to direct dermoscopic examination of the nail bed and matrix.Results We observed the presence of globules, streaks, and pigment network in the nail bed and matrix, which are dermoscopic features not seen in the nail plate.Conclusions This procedure enables visualization of dermascopic features not seen in the nail plate, making the diagnosis of melanocytic lesions easier.

Introduction Melanoma origin has always been a debated subject, as well as the role of adjacent melanocytic nevi. Epidemiological and histopathological studies point to melanomas arising either de novo or from a nevus. Methods Sixty-one melanomas found in association with a preexisting nevus were microdissected, after careful selection of cell subpopulations and submitted to Sanger sequencing of the BRAF, NRAS, C-KIT, PPP6C, STK19 and RAC1 genes. Each gene was evaluated twice in all samples by sequencing or by sequencing and another confirmation method, allele-specific fluorescent polymerase chain reaction (PCR) and capillary electrophoresis detection, or by SNaPshot Analysis. Only mutations confirmed via two different molecular methods or twice by sequencing were considered positive. Results The majority of cases presented concordance of mutational status between melanoma and the associated nevus for all 6 genes (40/60; 66.7%). Nine cases presented concomitant BRAF and NRAS mutations, including one case, in which both the melanoma and the adjacent nevus harbored V600E and Q61K double mutations. In two cases, both melanoma and associated nevus, located on acral sites were BRAF mutated, including an acral lentiginous melanoma. Conclusions This is the largest nevus-associated melanoma series molecularly evaluated to our knowledge. The majority of melanomas and adjacent nevi in our sample share the same mutational profile, corroborating the theory that the adjacent nevus and melanoma are clonally related and that melanoma originated within a nevus.

Background Topical tretinoin cream is the gold standard treatment for skin ageing, particularly photoaging. The purpose of tretinoin peel was to obtain similar results, but in a shorter time, however, there have been few controlled trials on its effectiveness. Objective To compare efficacy and safety of tretinoin 0.05% cream and 5% as a peeling agent on photoaging and field cancerization of the forearms. Methods Clinical trial with therapeutic intervention, prospective, randomized (computer‐generated randomization list), parallel, comparative (intrasubject) and evaluator‐blinded (except for histology and immunohistochemistry), including 24 women (48 forearms) aged over 60 years who have not undergone hormone replacement and categorized as Fitzpatrick skin phototype II or III. The forearms of the participants were randomized for treatment with 0.05% tretinoin cream three nights a week, or 5% tretinoin peel every 2 weeks. The opinion of the participant, severity of photoaging, corneometry, profilometry, high‐frequency ultrasound, histology (haematoxylin–eosin and Verhoeff stainings) and immunohistochemistry (p53, bcl‐2, Ki67 and collagen I) were assessed. Results One participant dropped out. The mean photoaging score reduced 20% and the mean actinic keratosis (AK) count reduced 60% with no difference between treatments. Three efficacy parameters showed opposite effects between the tretinoin treatments (P < 0.05%): (i) thickness of the corneal layer decreased with 0.05% tretinoin and increased by 5%; (ii) dermis echogenicity increased by 0.05% and decreased by 5% and (iii) Ki67 expression increased by 0.05% and decreased by 5%. There was good tolerability for both regimens. Conclusion Tretinoin as a cream 0.05% or peeling (5%) is safe and effective for the treatment of moderate photoaging and forearm field cancerization. The cream was superior in improving ultrasonographic parameters of ageing. Peeling was shown a superior performance in the stabilization of field cancerization.