The ORCHESTRA trial: A phase III trial of adding tumor debulking to systemic therapy versus systemic therapy alone in multi-organ metastatic colorectal cancer (mCRC).

TPS788 Background: In the current multidisciplinary approach of mCRC, local treatment of oligometastases is common practice. Results of large case series of selected patients treated with complete surgical resection of metastatic lesions suggest that this approach substantially improves survival rates to around 30-60%. Other techniques such as radiofrequency or microwave ablation (RFA, MWA), transarterial chemoembolization (TACE) or radiotherapy can also be applied in local treatment. Curative treatment options are generally not available for patients with extensive hepatic and/or extrahepatic mCRC. These patients primarily receive palliative systemic treatment consisting of combination chemotherapy as well as targeted agents. So far, reports on the benefit of local treatment for metastases in multi-organ mCRC have major limitations, including being small, non-randomized, single-center and retrospective. The benefit from local treatment of metastases for these patients should be established to allow for i...