EORTC1527/JCOG1609INT: Diffusion-weighted MRI (DW-MRI) assessment of liver metastasis to improve surgical planning (DREAM).

Abstract

TPS3633 Background: For patients with initially unresectable colorectal liver metastases (CRLM) with good clinical response to chemotherapy, the presence of disappearing liver metastases (DLMs) diagnosed by CT is a major independent prognostic factor. DW-MRI as well as contrast enhanced (CE)-MRI is recommended to detect and characterize CRLM. However, the correlation between radiological and pathological complete response has not been fully investigated using these latest imaging and pathology techniques. Our main aim is to demonstrate the added value of DW-MRI, CE-MRI to that of CT alone to provide precise assessment of the viability of DLMs. In addition, we aim to optimize the therapeutic management of CRLM patients. No prospective study has been conducted to determine the predictive value of DW-MRI combined with CE-MRI in confirming sites of DLMs and assessing their true status. Methods: This is the first collaborative study between EORTC, ESSO and JCOG with an integrated quality assurance program for imaging, surgery and pathology. Patients with unresectable CRLM will receive standard systemic chemotherapy and liver resection if resectable. Both CT and MRI (DW-MRI, CE-MRI and T1/T2) will be used to identify confirmed DLMs (cDLMs). cDLMs will be either resected or, if resection is not possible, followed-up without resection until 2 years after surgery to evaluate the true status of the cDLMs. The primary endpoint is negative predictive value (NPV) of DW-MRI, CE-MRI, T1/T2 and CT in confirming the status of cDLMs using as reference either the histopathological complete response or the absence of a local recurrence at the site of cDLMs during the follow up period of 2 years. The study aims at excluding a NPV≤0.85 and is powered under the alternative that the NPV≥0.95. The planned sample size is 92 evaluable (resected or left behind) cDLMs, with a 1-sided alpha of 5% and a power of 90% adjusting for within-patient correlation between cDLMs of 0.2 and an average number of 2 cDLMs per patient. Approximately 400 patients will be registered from European, Japanese and US sites over 3 years. As of February 2017, 2 patients have been enrolled. Clinical trial information: NCT02781935.