Benign lymphangioendothelioma presenting as a giant flank mass.

Benign lymphangioendothelioma is a rare lesion of controversial etiology and a histopathologic mimic of Kaposi sarcoma and so-called 'well-differentiated' angiosarcoma. Its most typical clinical presentation is as a slowly expanding, erythematous patch or plaque; it rarely presents as a large mass. We report the second case of a giant benign lymphangioendothelioma, which arose as a serpiginous mass involving most of the flank of an elderly male with no prior radiation exposure and with a remote history of herpes zoster infection. A biopsy revealed numerous anastomosing vascular channels extending from the superficial dermis to the subcutis that were dilated to progressively slit-like in architecture. The endothelial cells lacked cytologic atypia, hobnailing, or significant mitotic activity, and human herpesvirus-8 expression was absent. Positivity for podoplanin (D2-40) was observed in the endothelial cells, supporting a lymphatic phenotype. Furthermore, the lesional cells lacked immunohistochemical expression of Wilms tumor 1, providing further support of a malformative - rather than neoplastic - pathogenesis.

Cutaneous ciliated cyst of the scalp: a case report of a cutaneous ciliated eccrine cyst and a brief review of the literature.

Cutaneous ciliated cysts (CCC) are rare benign cysts known to occur in the lower extremities of females of reproductive age. Currently, there are 2 theories that attempt to explain the histogenesis of this rare entity. The theory of Mullerian heterotopia provides a plausible histogenetic explanation for the vast majority of CCC. A proposed alternative theory is the ciliated metaplasia of eccrine glands. We believe that previously reported cases of CCC include 2 distinct entities. We report, herein, the first case reported in the literature of a cutaneous ciliated eccrine cyst occurring on the scalp.

Collapsing angiokeloidal dermatofibroma.

A heterogeneous group of benign fibrohistiocytic lesions has been assembled under the umbrella term, dermatofibroma. These lesions share a morphology of bland spindled cells encompassed by and intercalating through thick dermal collagen; unique variants have been described based on secondary histologic features, some of which include aneurysmal, myxoid, lipidized, signet ring, angiomatous, and keloidal. Here, we present a distinct dermatofibroma variant henceforth known as collapsing angiokeloidal dermatofibroma identified in 2 patients with slowly growing nodules of the buttock and the arm. Microscopically, the lesions have a characteristic dermatofibroma appearance but are accompanied by unusual diffuse small caliber vessels whose walls are collapsed by a thick, eosinophilic, keloid-like substance. The eosinophilic material resembles the adjacent dermal collagen; however, it does not stain for type-4 collagen or type-1 procollagen, amyloid, or glycogen. Although the exact composition of the keloidal material remains ambiguous, the architectural novelty of collapsing angiokeloidal dermatofibroma serves to further expand the morphologic spectrum of benign fibrous histiocytomas, although highlighting the difficulty in distinguishing between it and similar lesions.

Margin Status in Shave Biopsies of Nonmelanoma Skin Cancers: Is It Worth Reporting?

CONTEXT: -The practice of reporting margin status in biopsies is relatively unique to biopsies of the skin and highly variable among pathologists. OBJECTIVE: -To address the accuracy of margin evaluation in shave biopsies of nonmelanoma skin cancers. DESIGN: -We collected shave biopsies of squamous and basal cell carcinomas that appeared to have uninvolved margins on routine sign out. We obtained deeper levels on corresponding tissue blocks until blocks were exhausted and examined them for tumor at biopsy margins. RESULTS: -Forty-seven consecutive cases were collected, including 20 squamous cell (43%) and 27 basal cell (57%) carcinomas. Eleven of 47 cases (23%) with negative margins at initial diagnosis demonstrated positive margins upon deeper-level examination. Margins of 8 of 27 basal cell carcinomas (30%) and 3 of 20 squamous cell carcinomas (15%) were erroneously classified as "negative" on routine examination. CONCLUSIONS: -No guidelines exist regarding the reporting of margins in nonmelanoma skin cancer biopsies, and reporting practices vary extensively among pathologists. We found that nearly one-quarter of positive margins in shave biopsies for cutaneous carcinomas are missed on standard histologic examination. Moreover, reporting of a positive margin may also be misleading if the clinician has definitively treated the skin cancer at the time of biopsy. For these reasons, and as routine exhaustion of all tissue blocks is impractical, the decision to include or exclude a comment regarding the margin status should be given conscious consideration, accounting for the clinical intent of the biopsy and any known information regarding postbiopsy treatment.

Cutaneous manifestations of multiple myeloma and other plasma cell proliferative disorders.

Plasma cell proliferative disorders cause rare but extremely varied dermatologic manifestations that may occur as an accompaniment to established diagnoses, or may be a first clue of an underlying neoplasm in the setting of clinical suspicion. In some instances skin lesions result from aggregation of misfolded monoclonal immunoglobulins or their fragments, as in light chain-related systemic amyloidosis. On other occasions the cutaneous lesions result from deposits of malignant plasma cells or monoclonal proteins. In still others, the dermatologic manifestations are related to antibody activity of monoclonal protein, as in many cases of cryoglobulinemia. This report provides insights into the well-recognized cutaneous manifestations associated with plasma cell disorders.

Alleviation of IgM monoclonal protein interference in nephelometric assays by sample treatment with reducing agent in a chaotropic salt solution.

In some patients, the presence of monoclonal IgM proteins can cause substantial false elevation in nephelometric assays. A 59-year-old woman with previously unrecognized Waldenström macroglobulinemia had high serum viscosity. Nephelometric analysis revealed elevated measured concentrations of IgG, IgA, and IgM. Pretreatment with a reducing salt solution yielded resolution of cross-linked immunoglobulins into a distinct IgM κ monoclonal protein band by immunofixation electrophoresis. Measured quantitative immunoglobulin measurements in treated and untreated specimens were compared. An approximately 50% drop in IgG and IgA concentrations was observed in the presence of reducing agent, while IgM concentrations were unchanged. We report that the addition of reducing agent solution can alleviate artifactual elevation of nephelometric determination of IgG and IgA concentrations. These results are consistent with dissociation of higher order IgM complexes, leading to reduction of nonspecific light scattering by IgM complexes in IgA and IgG nephelometric reactions.