ALDH3A1 and lung cancer: The fact that the expression of ALDH3A1 and AKR1B10 in the high-risk group is not significantly different from the lung cancer group but significantly different from the low-risk group in both biopsies and brushings in batch 1 and in the brushings in batch 2 means that it can be used to both rule out low-risk individuals from surveillance but also flag some patients from the high-risk groups with confidence for greater surveillance procedures (Figure 2 and Figure 3).