Solid cancer: the new tumour spread endpoint opens novel opportunities.

Novel androgen deprivation agents delay metastasis in non-metastatic, castration-resistant, prostate cancer (nmCRPC). The recent regulatory guidance: considerations for metastasis-free survival endpoint in clinical trials, opens new opportunities in cell biology, medicinal chemistry and advanced imaging. Past failures are the likely result of equating tumour shrinkage to efficacy, rather than inhibition of tumour spread. In the future, the selection of anti-metastasis drug candidates will probably be based on anti-migratory rather than anti-proliferative potential. Oligometastatic cancer coupled with advanced imaging can serve as a clinical proof-of-concept model.