OPTIMIzation of Treatment SElection and Follow up in Oligometastatic Colorectal Cancer

An open label 1:1 randomized phase II exploratory study investigating use of ctDNA-guided adjuvant chemotherapy compared to standard of care (SOC) after local treatment for metastatic colorectal cancer.

Patients are randomized 1:1 between SOC and ctDNA guided treatment and follow-up.

Escalation therapy comprises standard regimen of Fluorouracil (5-FU), Irinotecan and oxaliplatin (FOLFOXIRI), de-escalation therapy of monotherapy capecitabine or observation only. SOC is per institutional practice, based on national guidelines.

Inclusion criteria

• Radical intended treatment for metastatic spread from CRC, by resection, radiofrequency ablation, stereotactic body radiation therapy (or other experimental local treatment options) not including cytoreductive surgery (CRS) and hyperthermic intra-peritoneal chemotherapy (HIPEC)
• No evidence of further disease based on pre-treatment work-up according to SOC
• Age at least 18 years
• Eastern Cooperative Oncology Group performance status 0-2
• Clinically eligible for adjuvant triple CT at investigators decision.
• Adequate bone marrow, liver and renal function allowing systemic chemotherapy (Absolute neutrophil count ≥1.5x109/l and thrombocytes ≥ 100x109/l. Bilirubin ≤ 1.5 x upper normal value and alanine aminotransferase ≤ 3 x upper normal value, and calculated or measured renal glomerular filtration rate at least 30 mL/min)
• Anticonception for fertile women and for male patients with a fertile partner. Intrauterine device, vasectomy of a female subject's male partner or hormonal contraceptive are acceptable
• Written and verbally informed consent

Exclusion criteria

• Radiological evidence of distant metastasis, by CT- chest, abdomen, and pelvis
• Incapacity, frailty, disability and comorbidity to a degree that according to the investigator is not compatible with triple combination chemotherapy
• Neuropathy National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) grade > 1
• Other malignant tumor within 5 years except non-melanoma skin cancer or carcinoma in situ cervicis uteri
• Pregnant (positive pregnancy test) or breast feeding women
• Intolerance or allergy to 5FU, leucovorin, oxaliplatin, irinotecan or capecitabine