The HYP-RT Hypoxic Tumour Radiotherapy Algorithm and Accelerated Repopulation Dose per Fraction Study

Table 1

Default parameter values and ranges available in the tumour growth algorithm.

Parameter	Default	References	Comments
Cell total	10^8	N/A	The fully grown tumour cell limit.
Spercent, symmetrical stem cell division probability (%)	3%	N/A	This parameter was set to produce a 1% total stem cell population in the tumour.
Low oxygen limit for cell cycle arrest (mmHg)	1 mmHg	[43, 44]	At this pO2 level hypoxia-induced quiescence may be initiated.
Percentage of cells exiting the cell cycle (with pO2 <1 mmHg) (%)	50%	N/A	The total number of hypoxia-induced quiescent cells (<1 mmHg) = 3% using this parameter value, in line with the pO2 histogram used.
Tumour cell number threshold for hypoxia	10^6	[6, 7, 28, 45]	Hypoxia is modelled after the cell number is reached by allocating pO2 from the modelled pO2 histogram.
Hypoxic cell half life due to necrosis: pO2 < 1 mmHg (days)	4 days	[46, 47]	Due to the 4- to 10-day hypoxic cell lifetime in human colon carcinoma spheroids, and 2 days in xenograft HNSCC.