Inclusion Criteria:  Subject is scheduled for treatment on one of the five TrueBeam platforms at the NS Health QE2 site. Subject is receiving radiation therapy using a breath-hold technique (for example, lung, liver and left breast cancers).  Exclusion Criteria:  Patient is pregnant or has plans for pregnancy during the period of treatment. Patient is unwilling to consent to participating to the study, or for whom informed consent is not possible.