A Study of QBECO Versus Placebo in the Treatment of Colorectal Cancer That Has Spread to the Liver (PERIOP-06)

Inclusion Criteria: Adults aged 18 years or older at time of enrollment. Pathologic diagnosis of colorectal carcinoma with clinical diagnosis of liver metastases Planned to undergo resection of liver lesions for complete clearance of all visible metastatic disease. This will include those who may undergo synchronous resection of the primary colorectal cancer and/or those who may receive a combination of surgery and ablation to treat all lesions. Computerized Tomography (CT) of the chest, abdomen, and pelvis with intravenous (IV) contrast within 6 weeks prior to enrollment. MRI of the liver within 6 weeks prior to enrollment OR within 6 weeks prior to starting neoadjuvant chemotherapy (for patients treated with chemotherapy). Planned to receive the last dose of neoadjuvant chemotherapy at least 25 days prior to surgery (for patients treated with neoadjuvant chemotherapy). Agree to comply with the contraceptive requirements of the protocol when applicable Willing and able to either perform subcutaneous injections according to the study protocol, or receive the injections from a caregiver delegated by the participant. Able to provide informed consent or has a substitute decision maker capable of providing consent on their behalf. Exclusion Criteria: Prior or current evidence of extrahepatic metastases. Patients with small (<1.0 cm) indeterminate pulmonary nodules may be included at the investigator's discretion. Prior hepatic arterial infusion or embolization. Prior portal vein embolization, ablation, or liver resection are permitted. Patients with any invasive cancer history other than colorectal cancer in the last 5 years. In situ disease (e.g., melanoma in situ, ductal carcinoma in situ of the breast) or non melanoma skin cancers are permitted. Patients with a documented history of clinically severe autoimmune disease or a syndrome that requires systemic steroids or immunosuppressive agents. This includes patient requiring systemic treatment with either corticosteroids (> 10 mg daily prednisone equivalent, or depot corticosteroids in the 6 weeks before enrollment) or immunosuppressant drugs (such as azathioprine, tacrolimus, cyclosporine, etc.) within the 14 days prior to enrollment or a reasonable expectation that the patient may require such treatment during the course of the study. Inhaled or topical or inter-articular steroids, and adrenal replacement steroid doses ≤ 10 mg daily prednisone equivalent, are permitted in the absence of active autoimmune disease. Steroids used for premedication prior to chemotherapy or as part of a chemotherapy regimen are allowed. Patients with known active human immunodeficiency virus (HIV), Hepatitis B, or Hepatitis C infections. Pregnant patients or those who are nursing an infant