Pseudoxanthoma-like late-onset focal dermal elastosis

A 73-year-old woman presented with a 10-year history of asymptomatic coalescent flat pale yellow lesions forming a cobblestone pattern that resembled pseudoxanthoma elasticum over her neck, upper trunk and axillae. Skin biopsies from both the neck and axilla showed focal upper dermal elastosis with increase in structurally normal elastic fibres. There was no evidence of either pseudoxanthoma elasticum or solar elastosis in either biopsy. This under-recognized presentation has previously been identified as a distinct clinicopathological entity and termed late-onset focal dermal elastosis.     

Papillary dermal elastosis: a unique elastic tissue disorder or an unusual manifestation of pseudoxanthoma elasticum‐like papillary dermal elastolysis?

There are numerous acquired elastic tissue disorders, several of which present cutaneously with small yellow-to-white papules resembling plucked chicken skin. Differential diagnoses depend on the abnormalities within the network of elastic tissues. We report a case with distinct histologic features, which may represent a unique elastic tissue disorder or a variant of pseudoxanthoma elasticum-like papillary dermal elastolysis. Our patient's clinical presentation includes scattered 1–2 mm white-to-yellow papules without surface change on the upper back and neck region. Histology is characterized by foci of clumped, granular elastic tissue, which have replaced the oxytalan and elaunin fibers, alternating with foci of decreased concentrations of normal-appearing elastic fibers within the papillary dermis. Given its characteristics, we have termed this novel entity 'papillary dermal elastosis'.     

Familial acral localized late-onset focal dermal elastosis

Late-onset focal dermal elastosis is a rare disorder of elastic tissue, characterized by a local accumulation of elastic fibers in the mid and deep reticular dermis. This disorder occurs mainly in elderly people and consists of multiple yellow papules that are typically distributed on the sides of the neck and flexural areas, closely resembling pseudoxanthoma elasticum from the clinical point of view. We report 2 sisters who have presented with a 20-year history of multiple yellow papules, mainly located on the dorsum of their hands. They also had few lesions of similar morphology scattered on the anterior aspects of their wrists, thighs, and lower abdomen. Histopathologic study demonstrated a focal increase in thick, interlacing elastic fibers in the mid and deep reticular dermis. The most striking features of our cases were the early age of clinical presentation, the familial involvement, and the predominantly acral distribution of the lesions.     

Displacement of dermal solar elastosis in malignant melanoma

BACKGROUND: Ultraviolet radiation (UVR) is a major environmental causal factor for skin malignancy. In this study, we investigated the morphology of the solar elastosis (SE) band in benign and malignant melanocytic lesions. METHODS: We measured the SE band in perilesional and lesional skin of 13 melanomas (9 invasive and 4 in situ) and 11 melanocytic nevi (5 usual intradermal nevi, 4 blue nevi and 2 desmoplastic nevi) occurring in sun-exposed areas. RESULTS: The melanoma and nevus groups had similar age range, gender ratio and anatomic distribution. The mean SE thickness was 0.35 mm in melanomas and 0.29 mm in nevi (p = 0.56), indicating similar UVR exposure. There was a mean downward SE displacement (SED) of 0.43 mm in melanomas and essentially no displacement (-0.02 mm) in nevi (p < 0.005). Tumor cells and inflammatory host response were responsible for SED in melanoma. CONCLUSIONS: SED may help in the differential diagnosis of melanocytic lesions in sun-exposed areas. In melanoma, the new lesion depresses the pre-existing SE band. Conversely, the long-standing nevus co-exists with the SE band without significant displacement. Evaluation of the SE band may help to differentiate melanoma with chronic sun-induced damage as they have a distinct set of molecular alterations.     

Late-onset focal dermal elastosis: clinical and histological features

We describe two patients with lesions clinically resembling pseudoxanthoma elasticum and histologically exhibiting focal elastosis. with normal-appearing elastic fibres in the mid- and deep dermis. We consider that these skin lesions represent a previously undescribed entity, whose pathogenesis appears to be related to the ageing process.     

Late-onset focal dermal elastosis: an uncommon mimicker of pseudoxanthoma elasticum

Late-onset focal dermal elastosis is a rare disorder that presents clinically with the development of small white-to-yellow papules simulating pseudoxanthoma elasticum (PXE) in otherwise healthy adults in the seventh through ninth decades. It is characterized histopathologically by foci of increased normal-appearing elastic tissue in the reticular dermis. The disorder lacks any of the systemic complications of PXE and clinically resembles several other elastic tissue disorders that mimic PXE. We report two cases of late-onset focal dermal elastosis. The first is of a 75-year-old female who presented with symmetrically distributed, 2-5 mm white-to-yellow, discrete and coalescing, non-follicular papules on the posterolateral neck, anterior chest and axillae. The second case involves a 39-year-old female who presented with asymptomatic flesh-colored lesions on the posterior neck, back, antecubital and popliteal fossae, thighs, forearms and wrists. Skin biopsies in each case revealed aggregates of elastic fibers in the reticular dermis without calcification. The differential diagnosis of clinical and histopathologic imitators of PXE is discussed.     

Papillary dermal elastolysis similar to pseudoxanthoma elasticum

Papillary dermal elastolysis similar to pseudoxanthoma elasticum is an elastolytic disorder characterized by cutaneous lesions on the neck and in the supraclavicular region that are clinically similar to pseudoxanthoma elasticum, with no systemic complications. The histological examination shows a loss of elastic fibers in the papillary dermis. We report a case in a 76-year-old woman with typical lesions on the neck.     

Analysis of elastin metabolism in patients with late-onset focal dermal elastosis.

Late-onset focal dermal elastosis has recently been described as new clinical entity characterized by pseudoxanthoma elasticum-like eruptions and an accumulation of normal-appearing elastic fibres in the dermis. Elastin and collagen contents of the skin of 2 patients were 2- and 1.4-fold higher than in the skin of controls, respectively. A focal accumulation of elastin but not of fibrillin-1 was observed by immunohistochemical staining. The levels of type I and III collagen and elastin mRNAs isolated from cultured patient fibroblasts were elevated 2-3-fold compared with control fibroblasts. There was no significant change in the excretion of elastin peptides in the urine of patients and controls. These results suggest that the focal accumulation of elastic fibres in the patient skin may be related to overexpression of elastin rather than to altered degradation of elastin.     

Non-invasive evaluation of dermal elastosis by in vivo multiphoton tomography with autofluorescence lifetime measurements

The non-invasive differentiation of dermal elastic fibres from solar elastosis in vivo is of great interest in dermatologic research, especially for efficacy testing of anti-ageing products. To date, no studies on multiphoton excited fluorescence lifetime characteristics of human elastic fibres and solar elastosis are reported. The goal of the present work was the identification of differential criteria for elastic fibres and solar elastosis by the analysis of fluorescence decay curves acquired by time-correlated single photon counting in vivo multiphoton tomography. For this purpose, fluorescence lifetime measurements (FLIM) were performed with 47 volunteers of different age groups at sun-protected and sun-exposed localizations. Bi-exponential curve fitting was applied to the FLIM data, and characteristic differences between age groups and localizations were found in both relevant fit parameters describing the decay slope. The FLIM analyses have shown that dermal autofluorescence has different lifetimes depending on age and in part on localization.     

Lysozyme in abnormal dermal elastic fibers of cutaneous aging, solar elastosis and pseudoxanthoma elasticum

Staining of elastic fibres with antilysozyme antibodies has been noted previously. In this study, we examined the staining pattern of dermal elastic fibres in aging, solar elastosis, and lesional skin of pseudoxanthoma elasticum (PXE) using an antibody to lysozyme and the indirect-peroxidase technique. To assess the effects of aging, sun-protected skin (buttock) from a younger and an older group of patients was used. Sun damage was studied in skin specimens from varying sun-exposed body regions (trunk; head and neck). No staining was seen in sun-protected skin from younger individuals, whereas sun-protected skin from older persons had scattered positive fibres. Solar elastotic material was intensely positive and the number of positive fibres appeared to correlate with the amount of sun damage. Abnormal elastic fibres in PXE also stained positively, but less intensely, than fibres in solar elastosis. This study shows that changes in the elastic fibres due to degenerative processes or genetic factors results in altered antigenic expression of the fibres. This may be an epiphenomenon secondary to changes in proteoglycans, which are known to occur with solar elastosis and PXE, or may represent an adaptive phenomenon to maintain the elastic properties of the altered fibres or to decrease their antigenicity.     

Papular elastosis

I report two typical cases of a cutaneous disorder caused by sunlight, which is common in Phoenix, Arizona, "The Valley of the Sun." It currently masquerades under the misnomer, adult colloid milium. It generally presents clinically as asymptomatic, shiny, smooth, firm papules, 1 to 10 mm in diameter, involving chronically sun-damaged skin of adults. The papules are generally multiple, but may be solitary, with various colorations. Microscopically, the papules all show severe elastosis involving most of the papillary cutis. It is most important to biopsy these lesions because clinically they may mimic a variety of skin lesions, some of which would require further investigations and therapy. This is a distinct clinical form of severe solar elastosis, which I propose to term papular elastosis.     

Perforating calcific elastosis

A 69-year-old white multiparous woman presented a reticulated yellowish patch with scattered keratotic papules on her abdomen. Histopathological examination demonstrated pseudoxanthoma elasticum (PXE)-like changes. The diagnosis of perforating calcific elastosis (PCE) was made based on the absence of a personal and familial history of PXE. PCE is a localized acquired dermatosis and is considered to be a distinct clinical entity.     

Bullous solar elastosis

Solar elastosis is a recognized manifestation of chronic sun exposure affecting mainly Caucasian skin. Recognizable clinical manifestations of solar elastosis include cutis rhomboidalis nuchae, Favre-Racouchot syndrome, actinic comedonal plaque, nodular forms such as elastomas, elastic nodule of the ear and elastotic bands, collagenous plaques of the hand, and colloid milia. We report two patients with an unusual presentation of vesicular lesions clinically and histopathologically situated in zones of severe solar elastosis that has been previously referred to as bullous solar elastosis.     

Linear focal elastosis

Aims   Merkel cell carcinoma (MCC) is said to be the most aggressive of all skin cancers, with frequent metastases and a significant mortality rate. This study examined the role of mast cells and vascular density in the prognosis of Merkel cell carcinoma.
Methods   Mast cells and vessels were stained immunohistochemically in 36 MCC with antibodies to tryptase and CD34 respectively. The number of stainable mast cells and vessels were quantified within the tumours and surrounding stroma. Other clinical and histological parameters were also examined, statistically analysed and compared to subsequent clinical course and prognosis.
Results   Prognosis was poorer with higher mast cell numbers (p < 0.002) and with increased vascular density (p = 0.005). A one unit increase in mast cells predicted a 1.7 times increased risk of death. Prognosis was also adversely affected by the presence of lymphovascular invasion (p = 0.03) and larger tumour size (p = 0.05).
Discussion   Although factors predicting the behaviour of MCC are largely unknown, various parameters have been proposed as potential prognostic markers [ Llombart, 2005 ].
Mast cells are pivotal in immunity, but a prognostic role for mast cells in malignancies has also been suggested, possibly through mitogenesis and angiogenesis [ Ch'ng, 2006 ]. Vascular density, as a surrogate for angiogenesis, may have prognostic value in certain cancers, e.g. melanoma [ Depasquale, 2005 ].
In this study, increased mast cells counts and vascular density were associated with an adverse prognosis in MCC. Evaluation of mast cell infiltrates and vascular density can provide prognostic data and may ultimately help to guide appropriate treatment selection for this aggressive form of skin cancer.     

Bullous solar elastosis

Solar elastosis (SE) is a well-recognized manifestation of chronic sun exposure, mainly affecting white patients. Well-established clinical manifestations of SE include Favre-Racouchot syndrome, cutis rhomboidalis nuchae, actinic comedonal plaques, elastomas, elastotic nodules of the ears, elastotic bands, collagenous plaques of the hands and colloid millia. Bullous SE is a very unusual presentation of SE, which consists clinically of tense bullae on chronically sun-damaged skin and is characterized histopathologically by a dermal cleft within a dermis with severe SE. Bullous SE is a rare but characteristic clinical expression of SE.