Table 2.

Growth arrest doses (GAD, 0–6 days after treatment start) and half-maximal spheroid control doses (SCD₅₀, 0–35 days after treatment start) of MPC +HIFα and MPC +EV spheroids comparing external X-ray irradiation with [¹⁷⁷Lu]LuCl₃; diameters at treatment start: 492 ± 6 (MPC +HIF2α), 448 ± 3 (MPC + EV); significance of differences were calculated using t-test.

Treatment	Parameter	Measurand [Unit]	MPC + EV	MPC +HIF2α	p
X-ray	GAD	X-ray dose [Gy]	5.0 ± 0.3	16 ± 1.0	0.001
[177]LuCl3	GAD	Initial AV [MBq/mL]	0.3 ± 0.02	1.7 ± 0.7	0.05
[177]LuCl3	GAD	(approx. β− dose [Gy])	(2.2 ± 0.2)	(14 ± 6.0)
X-ray	SCD50	X-ray dose [Gy]	17 ± 0.2	21 ± 0.3	0.001
[177]LuCl3	SCD50	Initial AV [MBq/mL]	0.3 ± 0.02	0.6 ± 0.02	0.001
[177]LuCl3	SCD50	(approx. β− dose [Gy])	(2.7 ± 0.1)	(4.6 ± 0.2)