PGF and neoplasm: Placental growth factor levels in plasma and tumours correlate with tumour stage, vascularity, recurrence, metastasis, and survival in various tumour diseases (Ho et al, 2007; Fischer et al, 2008; Pompeo et al, 2009; Escudero-Esparza et al, 2009, 2010; Nagaoka et al, 2010).