Arriving at a definition of cutaneous paraneoplastic syndromes: A historic perspective on paraneoplasia.

Paraneoplastic syndromes are clinical manifestations resulting from the immune system's response to an underlying malignancy. Over the past three centuries, significant advancements in understanding cutaneous paraneoplastic syndromes have emerged, from early historical observations by pioneers like Armand Trousseau and Ferdinand von Hebra to more modern figures like Grant J. Anhalt. The roles of cytokines, growth factors, and immune pathways in these syndromes have enhanced our knowledge of tumor-host interactions and driven the development of targeted therapies that address the underlying malignancy and associated cutaneous symptoms. Despite these advancements, cutaneous paraneoplastic syndromes remain underrecognized in clinical practice. Recognizing the cutaneous manifestations that signal the possibility of an underlying malignancy enables early detection and intervention. Here, we review the definition and criteria of cutaneous paraneoplastic syndromes and historical context.