The Role of CD34 and D2-40 in the Differentiation of Dermatofibroma and Dermatofibrosarcoma Protuberans

Objective: Dermatofibroma (DF) is a benign fibrohistiocytic tumor whereas dermatofibrosarcoma protuberans (DFSP) has intermediate malignant potential. CD34 is the most commonly used antibody in differentiating these tumors. Various studies have stated the rates of D2-40 expression as 0-50% in DFSPs and 86-100% in DFs. Our aim in this study was to determine the expression of CD34 and D2-40 in DFs and DFSPs and the possible use of D2-40 in the differential diagnosis of these lesions. Material and Method: This is a retrospective study including 30 DF and 15 DFSP cases which were reevaluated for epidermal changes, the presence of a transmission zone (Grenz zone), infiltration of soft tissues, infiltration pattern and histologic subtypes in addition to cellular pleomorphism, nuclear atypia, and necrosis. A manual immunohistochemistry procedure was performed with D2-40 and CD 34 antibodies using a representative paraffin block. Results: The average age was 37.36 and 42.86 years in the DF and DFSP cases. The average diameter was 0.9 and 5.03 cm, respectively, for the DFs and DFSPs. There was a significant correlation between the two entities for sex, localization and diameter of the lesion. A significant difference was found between the positivity of CD34 and D2-40 in DFs and DFSPs. Conclusion: Additional immunohistochemical markers may be needed in DFs with CD34 positivity. Our results showed the additional helpful role of this marker in problematic cases

CAVERNOUS ANGIOMA MIMICKING MENINGIOMA

The authors present a rare case of cavernous angioma mimicking a meningioma in a 58-year-old man who presented with a headache and dizziness. There were no neurological deficits or other neurological symptoms or signs. An extra-axial mass lesion thought to be associated with diffusely well-enhanced falx in the postcontrast sections was noted in the posterior interhemispheric fissure near the posterior part of the corpus callosum splenium. Extra-axial cavernous angiomas (cavernomas) are extremely rare lesions. They most commonly occur in the parenchyma but have been occasionally reported to arise from the dura matter. Dural cavernous angiomas arise from dural sinuses, falx cerebri, tentorium cerebelli, cranial base dura, or internal auditory canal dura and convexity. Parenchymal cavernous angiomas classically have a ring of hemosiderin surrounding the lesions observed on magnetic resonance imaging, but dural cavernous angiomas do not display the same magnetic resonance imaging characteristics and occasionally exhibit a dural tail sign due to which they can often be misdiagnosed as meningiomas