PPP1R1B and neoplasm: Nuclear DARPP-32 expression did not remain associated with progression-free survival in multivariate Cox regression (HR = 0.387; 95% CI = 0.095–1.570; P = 0.184); when tumour size, lymph node status and NPI category were included (with individual Kaplan-Meier log rank significance of P = 0.012, P = 0.019 and P = 0.008 respectively).