PARP inhibition potentiates the anti-tumour effects of individual and combination treatments with chemotherapy and RIT. LL2 tumour-bearing mice were treated with PARPi on days 1 to 5, chemotherapy on days 1 and 2 and 5 MBq 177Lu-DAB4 on day 3. (A) Weight changes of mice after treatment. (B) Percentage change in tumour volume after treatment. (C) Kaplan-Meier survival analysis. ** p < 0.01 compared to same treatment group but without PARPi administration.