VWF and neoplasm: Platelet-tumor cell aggregates form through binding of platelet integrin αIIbβ3 to tumor cell integrin αvβ3 via RGD-containing proteins including fibrinogen, von Willebrand factor, and fibronectin (Kitagawa et al., 1989; Felding-Habermann et al., 1996), a process known as tumor cell-induced platelet aggregation (TCIPA) (Jurasz et al., 2004; Goubran et al., 2013).