Atypical vascular lesions extending outside the radiation field: a diagnostic challenge.

Atypical vascular lesion (AVL) is an uncommon, benign vascular proliferation seen in previously irradiated skin, most commonly after radiotherapy for breast cancer. Atypical vascular lesion and angiosarcoma may share overlapping clinical and histopathologic features. We report the first case of AVL occurring outside the field of radiation. This patient's clinical course and histopathology was overall consistent with AVL, including two biopsies with focal MYC positivity. However, due to variations in the interpretation of her histopathology, the management plans devised by two centers involved in her care were widely discordant and she was treated with chemotherapy and extensive surgery for angiosarcoma. Great care must be taken to distinguish between these entities, as treatment for angiosarcoma may be associated with significant morbidity.

Sézary syndrome-clinical and histopathologic features, differential diagnosis, and treatment.

Sézary syndrome (SS) is a rare subtype of cutaneous T-cell lymphoma marked by erythroderma, circulating neoplastic T cells, and poor prognosis. Its low incidence has made the study of its etiology, immunologic/molecular pathways, and effective treatments difficult. Because histopathology may be nonspecific in SS, microscopic findings must be correlated with the clinical presentation and the results of blood evaluation in order to make the diagnosis. Treatments that preserve, rather than compromise, the immune system are preferred.

Wong-type dermatomyositis: a mimic of many dermatoses.

Wong-type dermatomyositis (DM) is a rare variant characterized by keratotic follicular papules that may mimic pityriasis rubra pilaris. Histopathologic examination shows follicular and non-follicular epidermal invaginations filled with keratin. The diagnosis is often delayed. Twenty-four cases of Wong-type DM have been reported thus far in the literature. Herein, we report the clinical and histopathologic findings of three additional cases in order to raise awareness of the disorder.

Histologic findings following use of hydrophilic polymer with potassium ferrate for hemostasis.

Hydrophilic polymer with potassium salt is a hemostatic agent marketed for use by healthcare professionals and as an over-the-counter product available to healthcare consumers. In particular, dermatologic surgeons may use hydrophilic polymer for hemostasis in wounds left to heal by secondary intention. Foreign body reaction to hydrophilic polymer was recently reported. The microscopic findings in four additional patients treated with hydrophilic polymer are presented. The wounds of three patients were treated with hydrophilic polymer following a dermatologic surgical procedure while one patient used over-the-counter hydrophilic polymer on an abrasion. Three patients developed a foreign body reaction. Histopathologic examination revealed angulated fragments of deep purple material representing hydrophilic polymer admixed with round orange-red bodies and yellow-brown granules representing potassium ferrate. The components were found both free in the dermis and within multinucleated giant cells. Hydrophilic polymer must be differentiated from other materials observed in re-excision specimens, including ferric subsulfate, aluminum chloride and Gelfoam(®) (Pharmacia and Upjohn Co., New York, NY, USA).

Azathioprine-induced EBV-positive mucocutaneous ulcer.

Epstein-Barr virus (EBV)-positive mucocutaneous ulcer was recently described as a clinicopathologic entity occurring secondary to iatrogenic or age-related immune suppression. The histopathology of EBV-positive mucocutaneous ulcer reveals a polymorphous infiltrate including atypical large B-cells and Reed-Sternberg-like cells which are CD20-positive, CD30-positive and EBV-positive. The disorder follows an indolent and self-limited course. We report a case of EBV-positive mucocutaneous ulcer secondary to prolonged use of azathioprine for the treatment of pemphigoid and highlight the need for recognition of this disorder by dermatopathologists and dermatologists.

Clubbing: an update on diagnosis, differential diagnosis, pathophysiology, and clinical relevance.

Finger clubbing can be a striking physical finding. At other times, the presence of clubbing is difficult to establish by subjective examination alone and the profile angle or distal phalangeal to interphalangeal depth ratio are needed to confirm the finding. Most microscopic and imaging studies of clubbed fingers reveal hypervascularization of the distal digits. Recent research shows that when platelet precursors fail to become fragmented into platelets within the pulmonary circulation, they are easily trapped in the peripheral vasculature, releasing platelet-derived growth factor and vascular endothelial growth factor, promoters of vascularity and, ultimately, clubbing. Clinically, clubbing is associated with a number of neoplastic, pulmonary, cardiac, gastrointestinal, infectious, endocrine, psychiatric, and multisystem diseases. In narrowing the differential diagnosis, we recommend a detailed history and physical examination accompanied by focused laboratory and imaging studies. An algorithm for the evaluation of newly diagnosed clubbing is suggested.