The incidence of colorectal cancer is high, and hospitals and doctors at all levels have the opportunity to see such patients, but the level of expertise in oncology treatment is limited. Rectal cancer is different from colon cancer in terms of diagnostic and treatment decisions due to its special anatomical location. Some cases also require the cooperation of related multiple disciplines to discuss treatment plans. Here are a few words that experts in the field remind young doctors to pay attention to these four important issues that are especially easy to overlook in clinical work: 1. “Do not fight unprepared battles” Preoperative T-stage and N-stage should be accurate For preoperative examination of the primary site of rectal cancer, colonoscopy and pelvic CT examination are usually done, but for the primary foci However, ultrasound endoscopy or MRI is the more accurate means to determine the depth of invasion and surrounding lymph nodes, and MRI is better than the other two. High-resolution MRI can show the depth of tumor infiltration in rectal mesentery more clearly, and the examination of pelvic lymph nodes is more extensive. Of course, it is better to combine the two. 2.”Good steel is used on the edge of the knife” It is recommended to check CT for chest and MRI for liver. About 50%-60% of colorectal cancer is diagnosed with liver metastasis and/or lung metastasis, and it is recommended to check CT for chest and abdomen before treatment for locally advanced rectal cancer. If liver metastasis is found, it is recommended to add MRI, because CT examination has limitation on liver metastasis. metastases have limitations. For example, while CT examination reveals three liver metastases, MRI examination may reveal five to six lesions. If liver metastases and/or lung metastases are found, it is recommended to organize multi-disciplinary discussion, including oncologic intestinal surgery, hepatobiliary surgery, medical oncology, radiotherapy, pathology, imaging experts, and in cases with lung metastases, thoracic surgery experts are also required to participate, and decide the treatment plan according to the primary foci, metastases that can be cut, not cut, or potentially cut, or the patient’s symptoms and physical condition. 3.”Curve to save the country should be advocated” Emphasis on preoperative radiotherapy Patients with rectal cancer T3, T4/N+ have a higher possibility of recurrence after surgery, especially T4b/N+ patients, and many physicians believe that it is possible to do it after surgery, in fact, there are differences between patients’ preoperative and postoperative synchronous radiotherapy. In this regard, a randomized study conducted in Germany showed that preoperative radiotherapy significantly reduced the local recurrence rate and significantly increased the rate of anus preservation, in addition to avoiding radiation damage to the small intestine. The acute and long-term toxicities of preoperative concurrent radiotherapy were significantly lower than those of postoperative concurrent radiotherapy patients, and preoperative concurrent radiotherapy did not increase the incidence of anastomotic fistula, postoperative bleeding, or intestinal obstruction. Although the rate of delayed wound healing was higher in patients treated with preoperative concurrent radiotherapy than in those treated with postoperative concurrent radiotherapy, it did not reach a statistical difference. The 12-year follow-up results of this study suggested that preoperative radiotherapy significantly reduced the 10-year local recurrence rate. Because of the special anatomical location of rectal cancer, the anatomical structure of upper and lower rectal segments is different, and there is no plasma membrane coverage below the peritoneal fold, and many postoperative pathological reports of tumor invasion in the whole layer, which makes the subsequent staging less accurate and may result in over-staging or under-staging. Inadequate staging. In addition, the circumferential margins of the lower rectum should be reported to know whether the resection is R0 or R1. A transverse margin of <1 mm of the circumferential margin is considered a positive margin, and these play a crucial role in the subsequent treatment plan. Finally, the surgeon should be reminded that the surgeon should take care to mark the deepest area of intraoperative tumor invasion for the pathologist to assess the status of the margins.