@article{FringsGoebelerSchillingetal.2021, author = {Frings, Verena Gerlinde and Goebeler, Matthias and Schilling, Bastian and Kneitz, Hermann}, title = {Aberrant cytoplasmic connexin43 expression as a helpful marker in vascular neoplasms}, series = {Journal of Cutaneous Pathology}, volume = {48}, journal = {Journal of Cutaneous Pathology}, number = {11}, doi = {10.1111/cup.14066}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258412}, pages = {1335-1341}, year = {2021}, abstract = {Background Gap junctions consisting of connexins (Cx) are fundamental in controlling cell proliferation, differentiation, and cell death. Cx43 is the most broadly expressed Cx in humans and is attributed an important role in skin tumor development. Its role in cutaneous vascular neoplasms is yet unknown. Methods Fifteen cases each of cutaneous angiosarcoma (cAS), Kaposi sarcoma (KS), and cherry hemangioma (CH) were assessed by immunohistochemistry for expression of Cx43. Expression pattern, intensity, and percentage of positively stained cells were analyzed. Solid basal cell carcinomas served as positive and healthy skin as negative controls. Results Most cases of cAS presented with a strong Cx43 staining of almost all tumor cells, whereas endothelia of KS showed medium expression and CH showed mostly weak expression. In comparison with KS or cAS, the staining intensity of CH was significantly lower (Pā€‰ā‰¤ā€‰0.001). All tissue sections of both cAS and KS were characterized by a mostly diffuse, cytoplasmic staining pattern of the vascular endothelia. None of those showed nuclear staining. Conclusion The high-to-intermediate expression of Cx43 observed in all cases of cAS and KS suggests that this Cx may play a role in the development of malignant vascular neoplasms and serve as a helpful diagnostic marker.}, language = {en} } @article{GlutschWobserSchillingetal.2022, author = {Glutsch, Valerie and Wobser, Marion and Schilling, Bastian and Gesierich, Anja and Goebeler, Matthias and Kneitz, Hermann}, title = {PRAME expression as helpful immunohistochemical marker in rhabdoid melanoma}, series = {Dermatopathology}, volume = {9}, journal = {Dermatopathology}, number = {2}, issn = {2296-3529}, doi = {10.3390/dermatopathology9020019}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-284115}, pages = {148 -- 157}, year = {2022}, abstract = {Background: Rhabdoid melanoma is a rare variant of malignant melanoma with characteristic cytomorphologic features. Due to the potential loss of conventional melanocytic markers, histopathologic diagnosis is often challenging. We hypothesize that immunostaining for PReferentially expressed Antigen in MElanoma (PRAME) might have the potential to uncover the melanocytic origin of these dedifferentiated tumors. Methods: Four cases of rhabdoid primary melanomas were assessed by immunohistochemistry for expression of PRAME and conventional melanocytic markers. Immunohistochemical expression patterns were analyzed in the rhabdoid primaries and, if available, associated metastases. Results: All four cases of rhabdoid primary melanomas showed a strong nuclear positivity for PRAME, while the expression of conventional melanocytic markers S100, MART-1, SOX-10 and HMB-45 was variable between the analyzed cases. Conclusions: In summary, we report four cases of rhabdoid primary melanoma with high to intermediate expression of PRAME despite the partial and variable loss of other melanocytic markers. Hence, PRAME might facilitate the recognition of this highly aggressive entity to avoid misdiagnosis due to histopathologic pitfalls.}, language = {en} }