mFOLFOXIRI Plus Bevacizumab for Organ Preservation in Locally Advanced Rectal Cancer

Neoadjuvant mFOLFOXIRI plus bevacizumab may achieve tumor shrinkage and reduce micrometastases, offering a radiotherapy-free organ-preservation alternative for locally advanced rectal cancer. This phase II trial will enroll patients with stage II-III rectal cancer to receive six cycles of neoadjuvant mFOLFOXIRI plus bevacizumab, followed by watch-and-wait, local excision, or total mesorectal excision based on response.

Inclusion Criteria: * Sign the informed consent form and comply with the planned visits, study treatment, laboratory tests, and other trial procedures; * Age 18-75 years; * Histologically confirmed rectal adenocarcinoma; * The lower edge of the rectal tumor is \38.5°C) within 2 weeks prior to enrollment; * Concurrent presence of any of the following other diseases: human immunodeficiency virus (HIV) infection or acquired immunodeficiency syndrome (AIDS)-related illness; poorly controlled diseases including but not limited to non-infectious pneumonitis, diabetes mellitus, hypertension, pulmonary fibrosis, acute pneumonia, aneurysm, and coagulation disorders; or any other disease that, in the investigator's opinion, may affect the assessment of study endpoints; * Known or suspected allergy to the study drugs; * Pregnant or lactating women; * Patients with other serious physical or mental illnesses or laboratory abnormalities that may increase the risk of study participation, interfere with study results, or who are considered unsuitable for participation by the investigator.