Intraperitoneal LSTA1 in CRS-HIPEC

Inclusion Criteria: 1. Provision of signed and dated informed consent form. 2. Stated willingness to comply with all study procedures and availability for the duration of the study. 3. Participants must have histologically confirmed non-mucinous (\< 50% mucin) colorectal, ovarian, or appendiceal carcinoma with peritoneal metastases who are candidates for (cytoreductive surgery and CRS-HIPEC and have at least one peritoneal tumor nodule \> 5 mm (as determined by routine preoperative imaging and confirmed by intraoperative assessment). 4. Eligible and intended to undergo CRS-HIPEC per the investigators. This includes assessment of axial imaging (computed tomography, magnetic resonance imaging, positron emission tomography scan) of chest, abdomen, and pelvis, within 30 days of screening, which reveals peritoneal metastases amenable to complete cytoreduction per the investigators (i.e. limited small bowel/mesenteric metastases), lack of extra-peritoneal metastases (including intra-hepatic and pulmonary metastases), and lack of untreated biliary, gastrointestinal, and urologic obstruction. 5. Age ≥ 18 years. 6. Eastern Cooperative Oncology Group (ECOG) performance status \< 2. 7. Women of child-bearing potential with negative pregnancy test prior to undergoing CRS-HIPEC. 8. Adequate contraception for participants able to cause a pregnancy: Exclusion Criteria: 1. Participants who do not receive HIPEC at the time of CRS. 2. Any major surgery or irradiation within 30 days prior to prior to planned date of CRS-HIPEC. 3. Active infection (viral, fungal, or bacterial) requiring systemic therapy. 4. Known active hepatitis B virus (HBV), hepatitis C virus (HCV), tuberculosis, or human immunodeficiency virus (HIV) infection. 5. History of allogeneic tissue/solid organ transplant. 6. History or clinical evidence of central nervous system (CNS) metastases without exceptions 7. History of allergic reactions attributed to compounds of similar chemical or biologic composition to LSTA1 or other agents used in the study, including those discovered by other ongoing studies of LSTA1 or other agents used in the study. 8. Existing venous thromboembolism at the time of CRS-HIPEC. 9. Severe or uncontrolled medical disorder that would, in the investigator's opinion, impair ability to undergo CRS-HIPEC and receive study treatment. This includes, but is not limited to the following laboratory values and other parameters within 30 days prior to planned date of CRS-HIPEC: 1. Platelets \< 100,000/mm3 2. White blood cell count \< 3000/ mm3 3. Absolute neutrophil count \< 1,500/mm3 4. Serum albumin \< 2.5 g/L 5. Alanine transaminase (ALT) and aspartate aminotransferase (AST) \> 2.5 x upper limit of normal (ULN) in the absence of liver metastases or \> 5 x ULN in the presence of liver metastases 6. Bilirubin \> 1.5 x ULN 7. Glomerular Filtration Rate (per Modification of Diet in Renal Disease equation) \< 30 mL/min 8. Hemoglobin \< 9.0 g/dL (drawn 24 hours after a transfusion, if relevant) 9. International normalised ratio (INR) \> 2.0 (for patients not receiving therapeutic anticoagulation) 10. Adequate respiratory and cardiac function (PaO2 ≥ 60 mm Hg or oxygen saturation ≥ 92% on room air, and 12-lead electrocardiogram (ECG) with normal tracing or QT interval \< 470 ms) 10. Participants who are pregnant or nursing.