Objective There remains confusion between Langer's lines and wrinkle lines with respect to the optimal orientation of elliptical excisions on the trunk. This study sought to determine the directions of wound closure that would result in least wound tension after skin lesion excisions. Materials and methods Some 1181 consecutive skin lesion excisions were investigated (age range 13-95 years, median 64 years) using a tensiometer to determine directions of least wound tension. These lines were mapped. Skin tension measurements were taken during the procedure and analysed. The clear majority of excisions were for skin cancer and the others were for cysts or dysplastic naevi. Lesions such as lipomas, which entail incisional rather than excisional surgery (i.e. where overlying skin was not excised) were excluded. All lesions were cut out in a circular fashion following tension measurements. Closure was undertaken in the direction of least tension (biodynamic excisional skin tension line) and this was illustrated. This process was repeated in all cases where body site and direction of closure was mapped. Statistical analyses were undertaken on a series on the scalp and lower limb. Results Biodynamic excisional skin tension lines have a clear directional preference: scalp-coronal direction, limbs--vertical orientation of ellipses and trunk - mostly horizontal except oblique at the shoulder and scapular regions. Discussion Skin cancer excisions often end up with poor cosmetic results, owing to inconsistency in identifying the correct excisional wound closure lines. This has not been helped by the (hitherto) lack of large in vivo biomechanical studies, and because incisional lines and excisional lines have not been considered separately in surgical practice. Orientating ellipses or wound closures using biodynamic excisional skin tension lines offers a guide to reducing wound tension and minimising wound complications or scarring after cutaneous surgery.

A dysplastic nevus is also referred to as an atypical or Clark’s nevus and has been the topic of much debate in the fields of dermatology and dermatopathology. It is an acquired mole demonstrating a unique clinical and histopathologic appearance which sets it apart from the common nevus. These moles appear atypical clinically, often with a “fried-egg” appearance, and are commonly biopsied by providers due to the concern for melanoma. A clinical diagnosis of atypical nevi is based upon the presence of at least 3 of the following features: diameter greater than 5 mm, ill-defined borders, irregular margins, and lesional color variation. Individuals with these nevi have an increased risk for melanoma, but contrary to some individual beliefs, these are concerned banal nevi.

Globalisation, scientific and technical progress are the basis of numerous innovative therapies for oncologic and non-oncologic diseases. It is another matter how much and by whom they are desired, and whether they have to be applied. When and how often? Innovative approaches should go towards simplification, universal distribution and application while at the same time analysis between the potential initial investment and the achieved final result should be made. An illustrative example for this is the targeted therapy for melanoma with its low baseline criteria or basic rules for its surgical treatment. Another example could be the confocal microscopy in the context of dysplastic nevus syndrome. Therapies for various autoimmune diseases should also be considered critically. In the current OAMJMS issue, as well as in some of our other ideas and statements reported also in OAMJMS, we are trying to answer at least to a part of these dilemmas, to provoke a critical point of view and to ask some simple questions: "Should any innovation be considered as a face value? Which is potentially beneficial for our patients? How could we regulate the processes to minimise the need for expensive medications for certain diseases? And, of course, we are also turning to our own mistakes by visualising the results of them!

The presence of enlarged epithelioid/spindled nests located deep in the reticular dermis of a biphasic melanocytic neoplasm can mimic melanoma arising in a pre-existing nevus, causing over-interpretation of malignancy. We aimed to define the clinicopathologic significance of epithelioid/spindled nests in melanocytic nevi. Retrospectively using clinical and histologic information, we characterized 121 patients with a single lesion showing epithelioid/spindled melanocytes in the reticular dermis or subcutaneous fat, surrounded by melanophages, sometimes blending in with the adnexa. The majority of nevi occurred in women in the ages of 10 to 39 years, where the most frequent presentation was a changing mole. While 78% of the lesions displayed an anatomic (Clark's) level of IV-V, there was no ulceration, significant regression or inflammation. Up to 2 mitoses were found in only 12% of the cases, not correlating with the severity of cytological atypia. No recurrence or metastasis occurred during 45.5 months (mean) of clinical follow up in 26 patients. Notwithstanding the deep dermal extension, these findings suggest a benign histopathology and clinical outcome. Having compared the overlapping histopathology and clinical features between deep penetrating/clonal nevus and combined nevus, we posit that "inverted type-A nevus" might be considered a variant of the two.

A stepwise progression from melanocytic precursors to cutaneous melanoma is a well-established model, based on decades of careful observation and morphological analysis. The steps identified are benign melanocytic naevus, dysplastic naevus, 'radial growth phase' melanoma (including melanoma in situ) and 'vertical growth phase' melanoma (also termed tumourigenic melanoma). Recent genomic data have refined the understanding of the steps of melanoma development and their relationship to one another. These data support the existence of dysplastic naevi as distinct lesions; suggest the importance of clonal dynamics in the precursor steps of melanoma; and confirm the carcinogenic role of ultraviolet radiation throughout early melanoma development and progression. In this review, the steps of melanoma development and progression are summarised and discussed in the context of recent genomic studies. This new understanding of melanoma pathogenesis that has been facilitated through careful correlation of morphological and molecular features will allow the identification and development of robust biomarkers to assist in more accurate diagnosis and prognostication of melanocytic tumours.

This study reports on extensive experimental material covering more than 30 years of studying the genetics of mole voles. Sex chromosomes of Ellobius demonstrate an extraordinary case of mammalian sex chromosomes evolution. Five species of mole voles own three types of sex chromosomes; typical for placentals: XY♂/XX♀; and atypical X0♂/X0♀; or XX♂/XX♀. Mechanisms of sex determination in all Ellobius species remain enigmatic. It was supposed that the Y chromosome was lost twice and independently in subgenera Bramus and Ellobius. Previous to the Y being lost, the X chromosome in distinct species obtained some parts of the Y chromosome, with or without Sry, and accumulated one or several copies of the Eif2s3y gene. Along with enormous variations of sex chromosomes, genes of sex determination pathway and autosomes, and five mole vole species demonstrate ability to establish different meiotic mechanisms, which stabilize their genetic systems and make it possible to overcome the evolutionary deadlocks.

Benign melanocytic neoplasms present with a diverse array of well-known histopathologic patterns. It is imperative to recognize the benign patterns to render accurate diagnoses. We describe here an interesting and hitherto not described low-power architectural pattern of a benign melanocytic lesion: eccrine-centric melanocytic nevus. The patient was a 50-year-old African American woman who noticed a new mole on her foot that began as a dark speck but quickly grew larger. The lesion was excised to exclude the possibility of melanoma. Upon review of the specimen, the lesion was noted to demonstrate a distinctive pattern consistent with a melanocytic nevus of possible congenital onset. Remarkably, the ducts of eccrine glands were increased in density and the nests of melanocytes were found solely in a peri-eccrine distribution without melanocytes in any other locations (ie, interstitial, perifollicular). Additionally, all melanocytes in the nevus were rather heavily pigmented. Although this pattern demonstrated no atypical features that would cause one to consider it malignant to the trained eye, this presentation could implicate a metastatic disease (well-delineated nests in the dermis without concomitant interstitial component) and it is important to recognize.