CDKN2A and breast cancer: However, high levels of p16 mRNA expression have been related to a shorter event-free survival in acute lymphoid leukaemia (Mekki et al, 1999), breast cancer (Hui et al, 2000) and neuroblastoma (Omura-Minamisawa et al, 2001), and loss of p16 protein expression has previously been associated with the presence of metastatic disease at diagnosis in primary ESFT (P=0.026, n=20; Maitra et al, 2001).