Predicting Locally Advanced Rectal Cancer Response to NCT and NCRT With MRI

Inclusion Criteria:

1. pathological diagnosis of rectal cancer;
2. received neoadjuvant chemoradiotherapy before surgery;
3. before neoadjuvant therapy and before surgery, the patients received thin and high resolution MRI examination of the rectum.
4. before neoadjuvant therapy, colonoscopy, rectal contrast-enhanced ultrasound or MRI showed that the lower margin of the tumor was within 12cm from the anal margin;
5. pre-neoadjuvant clinical stage II/III (AJCC 7th edition);

Exclusion Criteria:

1. simultaneous distant metastatic tumor should be considered at the first diagnosis;
2. patients with distant metastasis were not considered at the initial diagnosis;
3. with other malignant tumors;
4. before neoadjuvant therapy, patients had received other relevant treatments;
5. to undergo palliative surgery or emergency surgery in the course of neoadjuvant therapy;