Fig. 2

A Kaplan–Meier estimates of the seven tumor models after radiochemotherapy (RCTx) with 30 fractions in 6 weeks, weekly cisplatin and nimorazole or carrier. Curves significantly different from the RCTx + carrier curve are marked with an asterisk *. Responder models showed improved tumor control rate (TCR) in both nimorazole-treated arms, low-responder models showed a positive trend in TCR only when nimorazole was administered with the first fraction [marked with (*)], non-responder models showed no positive effect in neither nimorazole-treated arm. B Summarized tumor control probability (TCP) for every tumor model irradiated with 30 fractions in 6 weeks with radiotherapy only (green line) performed in previous experiments [6, 27,28,29]. Estimated radiation doses for tumor control rate of 30–50% for RCTx are shown as gray, bold line. Black lines visualize the actual tumor control rate with RCTx from Kaplan–Meier estimates (dot = estimate, line = 95% confidence interval). FaDu, SAS, UT5 were classified as more radioresistant, UT8, CAL33, UT45, SAT as less radioresistant based on TCD₅₀ cutoff of 60 Gy. C Histological evaluation of the pimonidazole hypoxic volume (pHV) for the seven tumor models untreated (leftmost bars) and after RCTx with 10 fractions in 2 weeks combined with carrier (middle bars) or nimorazole (rightmost bars). The box plots displayed adhere to the Tukey style (see Methods). P value cutpoints: **** < 1e-04, *** < 0.001, ** < 0.01, * < 0.05. D Summary of the tumor models’ characteristics from (A–C), radioresistant abbreviated as radiores