We report nine examples of a distinct cutaneous plaque-like proliferation of fibroblasts and myofibroblasts. Eight of nine lesions were located in or around the shoulder, including axilla and upper arm. There was a predominance of women to men of 8:1. The lesions measured from 1 to 2 cm in greatest diameter. All patients were young adults (mean age 29.8 yr). All lesions involved the reticular dermis in a plaque-like fashion and extended to the upper part of the subcutaneous septa in seven cases. The lesions consisted of a proliferation of very uniform slender spindle-shaped cells arranged as well-defined elongated and intersecting fascicles with a predominantly parallel arrangement to the skin surface. There was no evidence of cytologic atypia and mitotic figures were infrequent. The spindle-shaped cells were separated by thin collagen fibers. Elastic fibers were preserved and some of them appeared thicker than normal. All adnexal structures were spared. Immunohistochemistry revealed that the cells stained positively for vimentin and muscle actin, but lacked smooth-muscle specific actin, desmin, and S-100 protein. Some dermal dendrocytes stained positively for Factor XIIIa, but the spindle-shaped cells were negative. Electron microscopy studies revealed a mixture of fibroblasts, myofibroblasts, and undifferentiated mesenchymal cells. All lesions were treated by conservative excision; follow-up information revealed no evidence of recurrence. We name this distinct lesion dermatomyofibroma. To the best of our knowledge, this entity has not been previously described in the literature.

C1-esterase inhibitor deficiency results in recurrent episodes of angioedema. Acquired deficiency has been associated with B-cell lymphoproliferative disorders, rheumatologic diseases or, in a small proportion of patients, the cause remains unknown. Of the malignancies associated with acquired C1-esterase deficiency, indolent lymphomas and plasma cell disorders are the most common. Aggressive lymphomas are rarely reported in such cases. We report the association of Burkitt lymphoma, a highly aggressive B-cell malignancy, which evolved seven months after the initial symptoms of acquired angioedema in a fifty-five year old man. Following treatment of the lymphoma, episodes of angioedema ceased. An association of acquired angioedema with Burkitt lymphoma has not previously been reported.