Concurrent malignant melanoma and cutaneous involvement by classical hodgkin lymphoma (CHL) in a 63 year-old man

UNLABELLED Classical Hodgkin lymphoma (CHL) is a lymphoproliferative disorder that has a bimodal age distribution, affecting young and elderly individuals, and is curable in more than 90% of patients. Here we report the coexistence of cutaneous CHL and malignant melanoma as the presentation of papules and a plaque, in an individual with remote history of systemic CHL. One of the biopsies showed a mononuclear cell infiltrate with Reed-Sternberg (RS) like cells that were positive for CD30 and CD15, but negative for CD45. A second concurrent biopsy showed an atypical melanocytic proliferation with significant pagetoid spreading and diffuse Melan-A staining. Based on morphology alone, it is almost impossible to distinguish CHL from other primary cutaneous lymphoproliferative disorders, such as CD30+ lymphoproliferative disorder (lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large-cell lymphoma), or even tumor stage mycosis fungoides when the epidermotropism is minimal. Additionally, bizarre melanocytic cells can also appear similar to RS cells. Our case illustrates the first case report of malignant melanoma and CHL in a patient presenting simultaneously. VIRTUAL SLIDES The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8979757349937225.