Comparative analysis of the clinical efficacy between primary Total Mesorectal Excision (TME) surgery and neoadjuvant chemotherapy combined with TME surgery for low-risk locally advanced rectal cancer. Randomly enrolling eligible patients into either the control group receiving neoadjuvant chemotherapy combined with TME surgery or the experimental group receiving primary TME surgery, and subsequently comparing the clinical outcomes of the two groups

Inclusion Criteria:

1. Newly diagnosed patients, aged 18 to 75 years;
2. Pathologically confirmed rectal adenocarcinoma;
3. Distance of the lower margin of the rectal tumor lesion from the anal margin <15cm;
4. High-resolution MRI indicates low-risk locally advanced rectal cancer: T1-3bN1-2 or T3aN0 or T3bN0; no involvement of the anal sphincter; negative mesorectal fascia (MRF) status; negative extramural vascular invasion (EMVI); no cancer nodules;
5. Exclusion of patients with non-local recurrence or distant metastases;
6. Absence of synchronous colorectal multiple primary cancers;
7. Adequate physical condition to tolerate surgery and neoadjuvant chemotherapy, including cardiac, pulmonary, hepatic, and renal functions;
8. The study physician assessed no difficulty in sphincter preservation;
9. patients and their families will be willing to participate in this study and provide written informed consent.

Exclusion Criteria:

1. Patients with concurrent other malignancies or a history of malignant tumors in the past;
2. Patients with intestinal obstruction, intestinal perforation, intestinal bleeding, or other conditions requiring emergency surgery;
3. Patients with tumor invasion into the external sphincter or levator ani muscles, or involvement of adjacent organs necessitating combined organ resection;
4. Patients with poor anal function or fecal incontinence before surgery;
5. Patients with a history of inflammatory bowel disease or familial adenomatous polyposis;
6. Patients recently diagnosed with other malignancies;
7. Patients with ASA grade ≥ IV and/or ECOG performance status score > 2;
8. Patients with severe liver or kidney dysfunction, significant cardiopulmonary impairment, coagulation disorders, or those with extreme underlying conditions unable to tolerate surgery;
9. Patients with a history of severe mental illness;
10. Pregnant or lactating women;
11. Patients with uncontrolled infections before surgery;
12. Patients with other clinical or laboratory conditions, as determined by the investigator, that render them unsuitable for participation in this trial.

Reasonable requests can provide relevant data, but must be used anonymously