At present, Multi-disciplinary team MDT (MDT) has become the model and development direction of clinical treatment of tumor. As early as 4 years ago, the Department of Colorectal Surgery of Beijing Cancer Hospital has carried out multidisciplinary discussion of colorectal tumors, which is fixed on every Monday afternoon. The basic composition includes: surgeons, physicians, radiotherapists, pathologists, diagnostic radiologists, basic oncology researchers, nurses, etc. The development of the Colorectal Cancer Multidisciplinary Comprehensive Treatment Collaborative Group has shortened the time from diagnosis to treatment and facilitated patients’ access to care. More importantly, after multidisciplinary consultation and discussion, individualized treatment plans suitable for specific patients are made according to the commonly accepted treatment principles and clinical guidelines. The following is an excerpt from a paper entitled “Multidisciplinary Comprehensive Treatment of Rectal Cancer” published in the Chinese Journal of Gastrointestinal Surgery, which I co-authored with Prof. Gu Jin and Dr. Du Changzheng. I hope that you can have a better understanding of the sub-multidisciplinary treatment. Multidisciplinary comprehensive treatment of rectal cancer 1. Clinical data The patient was male, 45 years old. He was admitted to the hospital in October 2009 due to blood in the stool for 3 months. The patient developed blood in stool in July 2009 without any obvious cause, the volume was small, fresh blood each time, not mixed with stool; stool 3-4 times/d, with urgency and heaviness; no nausea, vomiting, abdominal pain, abdominal distension, fever, poor appetite, fatigue and other discomforts, no significant changes in body mass. No abnormalities in past history and personal history. No family history of tumor and genetic disease. Physical examination: body temperature 36.5℃, pulse rate 65 times/min, respiration 18 times/min, blood pressure 125/85mmHg (1mmHg=0.133kPa). Murphy’s sign was negative, liver and spleen were not found under the ribs, abdominal percussion was bulging, hepatic turbinates were present, and there was no percussion pain in the liver area. Rectal palpation: the anus was normal in appearance, rectal mass was palpable, the lower edge of the tumor was 4 cm from the anus, involving the whole circumference, with hard texture, rough surface, poor mobility, and blood-stained finger sleeve. Auxiliary examination: MRI examination showed that the middle and lower rectum was occupied, invading the whole intestinal wall, and multiple enlarged lymph nodes were seen around the intestine. Fiberoptic colonoscopy showed an ulcerated mass in the lower rectum, involving the whole circumference, and the intestinal lumen was still open, and the rest was not abnormal. Chest X-ray and abdominal CT examination did not show any abnormality. Serum CEA and CA199 levels were normal. Pathological examination: moderately differentiated adenocarcinoma. 2. Preoperative discussion with Dr. Du Changzheng of the Department of Colorectal Surgery: The patient was a middle-aged male, with hematochezia as the main clinical manifestation, accompanied by increased frequency of bowel movements, urgency, and unformed stools; an occupying lesion in the lower rectum could be palpated on rectal palpation, involving the whole circumference, with hard texture and poor mobility; the biopsy suggested moderately differentiated adenocarcinoma. Based on the above clinical data, the patient’s diagnosis of rectal cancer was clear. Attending physician Zhao Jun, Department of Colorectal Surgery: Based on the patient’s medical history characteristics and auxiliary examination results, the diagnosis of rectal cancer is clear. Comprehensive evaluation of rectal cancer before treatment is crucial and directly affects the treatment strategy. The patient was clinically staged as cT3N + M0 through MRI and other adjuvant examinations, which belongs to locally progressive rectal cancer. Dr. Ying-Shi Sun, Chief of Radiology Department: Transrectal endoluminal ultrasound or MRI is currently advocated for the evaluation of rectal cancer. The latter is more valuable for evaluating the lymph node metastasis within the rectal mesentery and the circumferential cutting edge. MRIT2WI of this patient showed that the tumor invaded the whole intestinal wall and enlarged lymph nodes were visible in the peri-rectal mesentery, so cT3N+ was considered for clinical local staging. Dr. Gu Jin, chief physician of colorectal surgery: At present, the accepted treatment model for locally progressive rectal cancer is multidisciplinary comprehensive treatment, i.e. neoadjuvant radiotherapy or radiochemotherapy, combined with surgery and postoperative treatment on the basis of comprehensive evaluation. The depth of tumor infiltration and peri-intestinal lymph node metastasis of this patient are consistent with the indications of neoadjuvant radiotherapy for rectal cancer. Dr. Cai Yong, chief physician of radiotherapy department: the clinical stage of this patient is in line with the indication of neoadjuvant treatment. At present, neoadjuvant treatment for locally progressive rectal cancer includes preoperative radiotherapy and preoperative simultaneous radiotherapy and chemotherapy. The former mainly includes short-course radiotherapy with a total dose of 25Gy and completed in 5 sessions, and the modified short-course radiotherapy with a total dose of 30Gy and completed in 10 sessions recommended by the Chinese Anti-Cancer Association; the latter includes long-course radiotherapy combined with fluorouracil synchronized chemotherapy with a total dose of 45~50Gy and completed in 25~28 sessions. According to the experience of Peking University School of Clinical Oncology, the modified short-course radiotherapy regimen recommended by the Chinese Anti-Cancer Association has better clinical effects, higher patient compliance, and can significantly improve the rate of anus preservation in low rectal cancer, so the patient is proposed to undergo neoadjuvant radiotherapy with the modified short-course radiotherapy regimen. 3. After treatment, the patient received neoadjuvant radiotherapy according to the plan formulated in the preoperative discussion. After the completion of radiotherapy, the MRI showed that the tumor had decreased in extent, the intestinal wall was reactive edema, and the peri-intestinal lymph nodes were smaller than before treatment. The patient underwent low anterior resection of rectal cancer 2 weeks after the completion of radiotherapy. The tumor was found to be located in the lower rectum and confined to the intestinal wall. Post-operative pathological examination: medium-differentiated adenocarcinoma of rectal ulcer type, invading the intrinsic muscular layer, with massive necrosis and fibrosis in the tumor tissue; no cancer metastasis in the peri-intestinal lymph nodes, no choroidal cancer emboli, and no cancer residue in the distal and proximal margins and peri-annular margins. After surgery, the patient received 8 cycles of chemotherapy with XELOX regimen. There was no abnormality in the postoperative review 3 months later. Six months after surgery, CT examination showed multiple occupying sites in the liver, the largest of which was about 1.6cm×1.8cm in size, and liver metastasis was considered. Serum CEA, CA199 and AFP were normal. Colonoscopy and pelvic MRI examination did not show any anastomotic recurrence and no other organ metastases were seen.