GSTM1 and cancer: The proportion of anaemic patients with cancers and a negative FIT was similar across the groups: 72.7 per cent in the initial single-FIT cohort, 66.7 per cent in the overall double-FIT cohort, and 66.7 per cent in the completed DT protocol groups where both or the only FIT value was less than 10 μg Hb per g.