tokens: Whereas PHA -induced proliferation of PBMCs derived from patients with breast cancer preoperatively was significantly decreased when compared with data obtained in healthy control individuals ( P < 0.001 ) , the degree of the defect in PHA -induced proliferation of PBMCs depended upon the tumour burden as manifested by tumour size and axillary lymph node involvement ( P < 0.003 in each case ) .