Dermoscopic features of acral lentiginous melanoma in a large series of 110 cases in a white population

BACKGROUND

Acral lentiginous melanoma (ALM) is a rare but distinctive subtype of melanoma. The diagnosis is often delayed and misdiagnosis is common, due to frequently unusual clinical presentation and a higher rate of amelanosis than in other melanoma subtypes.

OBJECTIVES

We aimed to investigate the dermoscopic features of a large series of ALM in a white-skinned population, in order to emphasize their diagnostic value.

METHODS

All recorded dermoscopic photographs of ALM, including nail unit variants, were collected from the files of the University Hospital Department of Dermatology (Lyons, France) and reviewed.

RESULTS

In total 110 lesions, including 66 (60%) palmoplantar ALM and 44 (40%) ALM of the nail apparatus, were analysed for dermoscopic characteristics. The mean Breslow thickness was 2.6 mm. In volar skin melanomas, the two most prevalent patterns were irregular diffuse pigmentation (60%) and the parallel-ridge pattern (53%). Minor dermoscopic patterns, commonly noted in benign lesions, were also detected but only focally within the lesions. Among the 44 nail unit lesions, 31 (70%) presented irregular lines with variegations in colours, spacing, width and disruption of parallelism. Two cases of melanonychia striata had a triangular shape. Both corresponded to early ungual ALM. Association with subungual haemorrhage was not uncommon. The study included 37 (34%) amelanotic melanomas. However, dermoscopy enabled detection of microscopic remnants of pigmentation in most cases. The vascular pattern found in almost half of these lesions was polymorphous, with combinations of milky-red areas (95%), linear irregular vessels (49%), dotted vessels (43%) and hairpin vessels (41%).

CONCLUSIONS

The presence of a parallel-ridge pattern and/or irregular diffuse pigmentation within the lesion is highly indicative of melanoma on volar skin. An irregular lines pattern is the most prominent dermoscopic feature of pigmented ALM of the nail apparatus. Amelanotic ALM either in volar skin or in nail apparatus is characterized by remnants of pigmentation and a polymorphic vascular pattern.

[Successful use of combined corticosteroids and rituximab in the treatment of recalcitrant epidermolysis bullosa acquisita]

BACKGROUND

Epidermolysis bullosa acquisita (EBA) is a rare autoimmune subepidermal blistering disease; it is potentially serious and is often refractory to conventional treatments, including corticosteroids. We report a new case of successful treatment of EBA using rituximab (anti-CD20 antibody) without relapse after 1 year of follow-up.

CASE REPORT

A 76-year-old man was seen for blisters of the skin and mucosa, atrophic scars and milia on areas of friction. The diagnosis of EBA was made on the basis of histological and immunohistochemical criteria. The patient was unsuccessfully treated with topical steroids, dapsone, topical tacrolimus, systemic steroids, mycophenolate mofetil, doxycycline and methotrexate. Four weekly infusions of rituximab of 375 mg/m(2) body area were performed, combined with systemic steroids: they proved beneficial within 3 weeks, with a noticeable improvement and no further blisters at 7 months. After 1 year of follow-up, the skin disease is still stable with 5 mg/day of prednisone alone being given.

DISCUSSION

This is the eighth reported case of treatment of EBA with rituximab and the sixth successful therapeutic outcome, with good steroid sparing effect and undeniable improvement in quality of life within several months and good tolerability at 12 months of follow-up. This treatment may be proposed early in cases of EBA refractory to conventional treatments. However, clinical observation is necessary to study potential long-term adverse effects.

Mycosis fungoides mimicking an annular erythema

Diagnosis of mycosis fungoides (MF) can be difficult due to its highly variable presentation and the sometimes nonspecific nature of the histological and molecular findings. MF classically presents as patches, plaques and tumours as originally described by Alibert and Bazin, but many other clinical presentations may occur, often mimicking other inflammatory conditions. We report a case of MF presenting as typical centrifugal annular erythema.

Scabies with clinical features and positive darier sign mimicking mastocytosis

Scabies is a common human parasitic infection in infants and children. But diagnosis pitfalls are frequent in infants, in whom the clinical presentation is usually atypical and different from adults. We report a misleading case of a 5-month-old child, who presented with pruritic brown-red macules of the trunk showing a positive Darier's sign, suggestive of an urticaria pigmentosa.

[Diffuse systemic sclerosis after occupational exposure to trichloroethylene and perchloroethylene]

BACKGROUND

Diffuse systemic sclerosis (DSS) is an autoimmune disease that is most often endogenous but which can also be induced by exogenous substances of occupational origin.

PATIENTS AND METHODS

We report a case of DSS involving prolonged intermittent occupational exposure to solvents (trichloroethylene [TCE] and perchloroethylene [PCE]). The disease was rapidly fatal with cardiac arrest secondary to myocardial fibrosis.

DISCUSSION

In the event of exposure to TCE/PCE, we suggest more systematic prevention and diagnosis of DSS.

[Lymphomatoid papulosis in childhood: six case reports and a literature review]

BACKGROUND

Lymphomatoid papulosis (LyP) is a rare lymphoproliferative disorder. It is now included in the World Health Organisation (WHO) classification of cutaneous lymphomas. Although frequently described in adults, there have been only a few reported cases of LyP in children; diagnosis is often difficult in this population and no clear guidelines have been established regarding management or monitoring. In this article we report six new cases of LyP in children.

PATIENTS AND METHODS

This is a retrospective study of six children, aged between two and 11 years, seen at the Hôtel-Dieu Hospital in Lyon and at the Grenoble Hospital Centre between 2005 and 2008. Each child underwent skin biopsy for histological and immunohistochemical analysis.

RESULTS

All six children presented papulonodular lesions on the limbs and trunk, in some cases necrotic, present for different times and developing in episodes. Histology and immunolabelling announces in all six cases militated in favour of LyP type A, with large CD30+ and CD15- cells dispersed in an inflammatory dermal infiltrate made up for the most part of lymphocytes, polynuclear neutrophils, eosinophils and a small number of histiocytes.

DISCUSSION

Only around 60 cases of LyP have so far been reported in children, principally type A. Association with malignant lymphoma occurs, with high risk in relation to the general population of the same age. Clinical diagnosis is confirmed histopathology and immunolabelling. There is currently no consensus regarding therapeutic management. First-line treatment generally comprises therapeutic abstention or dermal corticosteroids. Methotrexate and phototherapy constitute possible alternatives but should be used only in very disseminate or debilitating forms of the disease.

CONCLUSION

The presentation and course of LyP of childhood differs very little from the adult form. Cases of associated lymphoma have been reported. Although regular clinical monitoring is recommended, there is no call for routine laboratory testing.