Metastatic spread of cancer from its primary site to distant organs is the commonest cause of death from cancer. The term oligometastases describes an intermediate metastatic state, in which cancer exists as a limited number of metastases at first, before cells acquire the ability to metastasise more widely. For the large majority of solid cancers, once metastatic disease has been diagnosed the chances of cure are small. There are several situations where this is not the case, but it is not known if stereotactic body radiotherapy (SBRT) for oligometastatic disease will alter outcomes or whether the toxicity burden of this treatment is justified. SBRT is targeted radiotherapy which destroys cancer cells in the area of the body it is aimed at however low dose radiation may be received by surrounding tissue.
It is difficult to quantify incidence of patients with multiple primary cancers developing at intervals that are representative of oligometastatic stage IV disease, (defined for the purposes of this trial as ≤ 3 metastatic sites). However an increase in the use of surveillance imaging, together with improved diagnostic sensitivity has led to the diagnosis of patients with asymptomatic oligometastatic relapse becoming a more common clinical occurrence. The CORE study is a randomized controlled clinical trial that will be conducted in patients with cancer in one of three primary sites where oligometastatic disease relapse is a common clinical scenario: breast, prostate and non-small cell lung cancer (NSCLC). The clinical trial will evaluate the use of SBRT in this patient population.
Eligible patients who consent to participate in this clinical trial will be randomized to receive standard care or standard care plus SBRT.