Table 4.

Considerations for chronoradiotherapy. Listed are some of the factors that should be considered when grouping patients and comparing results in future chronoradiotherapy studies and clinical trials. DLMO = dim-light melatonin onset.

Patient Factors	Treatment Factors
Circadian phase, biomarkers *	Time of day, narrow ranges with significant gaps
Chronotype	Primary cancer site
Clock gene analysis	Disease stage, grade, mutations
Demographics, exposure history	Radiation dose, modality, fractionation
Radiation toxicity, tumor control	Consistency of radiation times, carryover effects
Microbiome analysis	Adjuvant/definitive therapies, immune suppression

* E.g., clock gene expression, DLMO, cortisol spike, core body temperature, heart rate variability, actigraphy, sleep questionnaires.